fix(metrics): reject missing histogram counts (#9039)

* feat(s3): serve Veeam SOSAPI system and capacity XML

Authenticated GET and HEAD of the two well-known SOSAPI keys return
generated XML, and read preconditions use that generated ETag and
Last-Modified. Mutations of those keys are rejected while the feature
is on.

Co-authored-by: RustFS <hello@rustfs.com>

* fix(s3): simplify Veeam quota metadata lookup

Co-Authored-By: heihutu <heihutu@gmail.com>
Co-Authored-By: zhi22915 <qiuzgang@gmail.com>

* fix(s3): harden Veeam SOSAPI capacity and reads

Co-Authored-By: heihutu <heihutu@gmail.com>
Co-Authored-By: zhi22915 <qiuzgang@gmail.com>

* fix(s3): bind Veeam capacity to bucket identity

Co-Authored-By: heihutu <heihutu@gmail.com>
Co-Authored-By: zhi22915 <qiuzgang@gmail.com>

* fix(s3): protect virtual objects and coalesce refreshes

Co-Authored-By: heihutu <heihutu@gmail.com>
Co-Authored-By: zhi22915 <qiuzgang@gmail.com>

* test(e2e): refresh Veeam profile selections

Co-Authored-By: heihutu <heihutu@gmail.com>
Co-Authored-By: zhi22915 <qiuzgang@gmail.com>

* test(e2e): bound pagination fixture writes

Co-Authored-By: heihutu <heihutu@gmail.com>
Co-Authored-By: zhi22915 <qiuzgang@gmail.com>

---------

Co-authored-by: Hauser <housemecn@gmail.com>
Co-authored-by: heihutu <heihutu@gmail.com>
Co-authored-by: zhi22915 <qiuzgang@gmail.com>

.config/e2e-full-selection.txt

@@ -1,2 +1,2 @@
-sha256-darwin=a67a347f26be186c598b5beaf68e6bcbe1855350a35e1423dd5b8a81bcba06a5
-sha256-linux=ad4fabe811c6cca1aba89fad34ccd404b5832a6a955875c2826f6e0fa1ea4f1f
+sha256-darwin=67251cb7d9978d38e899268cac4d7898297ff7e5b5c48c9c1546dc760b93568d
+sha256-linux=673da76c2e5710c4622fe2fa32d2b297730895769487fcf1152ee1c2366f32f4

.config/e2e-smoke-selection.txt

@@ -1 +1 @@
-sha256=f065e7071aac9d48a7c1b301f328fa7cc14f11c4e7dc46da3e55057c4ea29bd5
+sha256=e9dc896774122a304e2b8b90f28c82d4d4e0af8ded36a82b147b30945ec994e3

.config/nextest.toml

@@ -128,7 +128,7 @@ setup = 'ecstore-large-stack'
 # path on a real store; measured with RUST_MIN_STACK on 2026-10-15 they need
 # 2016-2040 KiB of the 2 MiB libtest default and overflowed on Linux CI.
 [[profile.default.scripts]]
-filter = '(package(rustfs) & test(/^(admin::handlers::replication::target_repair_tests::[a-z_]+|admin::handlers::site_replication::tests::durable_iam_state_apply_iam_item_rejects_a_stale_recreate_after_a_replicated_delete|admin::service::federated_identity::tests::(binding_keeps_explicit_iam_mapping_strict|markerless_legacy_oidc_session_crosses_auth_and_iam_deletion_boundaries)|storage::scanner_dirty_journal::tests::(clear_callback_keeps_unknown_coverage_until_all_pending_work_is_confirmed|owned_journals_keep_peer_records_after_interleaved_writes_and_clear))$/)) | (package(rustfs-heal) & ((binary(heal_b5_versioned_regression_test) & test(/^serial_tests::(test_heal_unversioned_bucket_e2e|test_historical_null_recursive_heal_restores_physical_versions|test_recursive_deep_heal_reports_stale_delete_marker_repair)$/)) | (binary(usage_observation_read_repair_test) & test(=usage_observation_read_repair_survives_snapshot_cleanup)))) | (package(rustfs-test-utils) & test(=data_usage_snapshot_tests::data_usage_snapshot_recovery_wires_primary_backup_and_negative_cache))'
+filter = '(package(rustfs) & test(/^(admin::handlers::replication::target_repair_tests::[a-z_]+|admin::handlers::plugin_attempt::v2_tests::delegation_v2_persists_and_vends_with_real_parent_intersection|admin::handlers::site_replication::tests::durable_iam_state_apply_iam_item_rejects_a_stale_recreate_after_a_replicated_delete|admin::service::federated_identity::tests::(binding_keeps_explicit_iam_mapping_strict|markerless_legacy_oidc_session_crosses_auth_and_iam_deletion_boundaries)|storage::scanner_dirty_journal::tests::(clear_callback_keeps_unknown_coverage_until_all_pending_work_is_confirmed|owned_journals_keep_peer_records_after_interleaved_writes_and_clear))$/)) | (package(rustfs-heal) & ((binary(heal_b5_versioned_regression_test) & test(/^serial_tests::(test_heal_unversioned_bucket_e2e|test_historical_null_recursive_heal_restores_physical_versions|test_recursive_deep_heal_reports_stale_delete_marker_repair)$/)) | (binary(usage_observation_read_repair_test) & test(=usage_observation_read_repair_survives_snapshot_cleanup)))) | (package(rustfs-test-utils) & test(=data_usage_snapshot_tests::data_usage_snapshot_recovery_wires_primary_backup_and_negative_cache))'
 setup = 'ecstore-base-stack'
 
 [[profile.default.scripts]]
@@ -419,7 +419,7 @@ setup = 'ecstore-large-stack'
 
 # These cross-crate real-storage fixtures need the same bounded stack as ECStore tests.
 [[profile.ci.scripts]]
-filter = '(package(rustfs) & test(/^(admin::handlers::replication::target_repair_tests::[a-z_]+|admin::handlers::site_replication::tests::durable_iam_state_apply_iam_item_rejects_a_stale_recreate_after_a_replicated_delete|admin::service::federated_identity::tests::(binding_keeps_explicit_iam_mapping_strict|markerless_legacy_oidc_session_crosses_auth_and_iam_deletion_boundaries)|storage::scanner_dirty_journal::tests::(clear_callback_keeps_unknown_coverage_until_all_pending_work_is_confirmed|owned_journals_keep_peer_records_after_interleaved_writes_and_clear))$/)) | (package(rustfs-heal) & ((binary(heal_b5_versioned_regression_test) & test(/^serial_tests::(test_heal_unversioned_bucket_e2e|test_historical_null_recursive_heal_restores_physical_versions|test_recursive_deep_heal_reports_stale_delete_marker_repair)$/)) | (binary(usage_observation_read_repair_test) & test(=usage_observation_read_repair_survives_snapshot_cleanup)))) | (package(rustfs-test-utils) & test(=data_usage_snapshot_tests::data_usage_snapshot_recovery_wires_primary_backup_and_negative_cache))'
+filter = '(package(rustfs) & test(/^(admin::handlers::replication::target_repair_tests::[a-z_]+|admin::handlers::plugin_attempt::v2_tests::delegation_v2_persists_and_vends_with_real_parent_intersection|admin::handlers::site_replication::tests::durable_iam_state_apply_iam_item_rejects_a_stale_recreate_after_a_replicated_delete|admin::service::federated_identity::tests::(binding_keeps_explicit_iam_mapping_strict|markerless_legacy_oidc_session_crosses_auth_and_iam_deletion_boundaries)|storage::scanner_dirty_journal::tests::(clear_callback_keeps_unknown_coverage_until_all_pending_work_is_confirmed|owned_journals_keep_peer_records_after_interleaved_writes_and_clear))$/)) | (package(rustfs-heal) & ((binary(heal_b5_versioned_regression_test) & test(/^serial_tests::(test_heal_unversioned_bucket_e2e|test_historical_null_recursive_heal_restores_physical_versions|test_recursive_deep_heal_reports_stale_delete_marker_repair)$/)) | (binary(usage_observation_read_repair_test) & test(=usage_observation_read_repair_survives_snapshot_cleanup)))) | (package(rustfs-test-utils) & test(=data_usage_snapshot_tests::data_usage_snapshot_recovery_wires_primary_backup_and_negative_cache))'
 setup = 'ecstore-base-stack'
 
 [[profile.ci.scripts]]

.github/workflows/README.md

@@ -16,7 +16,7 @@ Every other label in this repository is capacity RustFS pays for. ARC pods and l
 | `sm-standard-2` | RustFS | ARC pod, Ubuntu 24.04, minimal image: no `gh`, no C toolchain; Docker only on the `dind-` label | only a job that a hosted runner cannot run (see the placement rule) |
 | `sm-standard-4` | RustFS | ARC pod, Ubuntu 24.04, 14 CPUs and 28 GB (the label is not the core count), large disk | workspace-scale Cargo builds |
 | `ubicloud-standard-16-arm` | RustFS | Ubicloud VM, alias of `ubicloud-standard-16-arm-ubuntu-2404`: Ubuntu 24.04 arm64, 16 vCPU, 48 GB, 300 GB disk. Reached through the `build.yml` matrix, so `actionlint.yaml` does not list it | native aarch64 release builds (`linux-aarch64-musl`, `linux-aarch64-gnu`) |
-| `dind-sm-standard-2` | RustFS | ARC pod with Docker-in-Docker | image builds that need `buildx` and a registry push |
+| `dind-sm-standard-2` | RustFS | ARC pod with Docker-in-Docker | Docker workloads with a measured resource or environment requirement beyond the hosted runner |
 | `smoke-testing`, `pf-testing` | RustFS | long-lived lab machines | the packaged functional chain and performance suites |
 
 The self-hosted pods and the hosted image are both Ubuntu 24.04, so a binary built on one runs on the other; `ci.yml` builds the debug binary on `sm-standard-4` and runs it on both pools.
@@ -27,11 +27,15 @@ A job runs on `ubuntu-latest` unless it has one of these reasons, and the reason
 
 1. **Disk.** It restores or produces the workspace `target/`: `cargo build` or `cargo test` with `--all-targets`, `cargo nextest run --all`, or any reader of the `ci-dev` / `ci-feat-*` caches. The workspace test build leaves about 64 GB in `target/`; a hosted runner has about 14 GB.
 2. **Critical-path CPU.** It is a build that several downstream lanes wait on and would blow its timeout at 4 vCPU (`build-rustfs-debug-binary` gates the e2e and s3-tests lanes).
-3. **Hardware.** Native aarch64, Docker-in-Docker, or the lab machines.
+3. **Hardware or environment.** Native aarch64 or access to the lab machines. Docker alone is not a reason: hosted Ubuntu ships Docker and supports the QEMU and Buildx setup actions.
 4. **Cache ownership.** It reads a `rust-cache` key that a self-hosted job writes (see the cache rule below).
 
 Jobs that do only the following have no reason to be self-hosted: shell or Python scripts, `cargo fmt`, `cargo deny`, typos, actionlint, API calls (`gh`, dependency review, issue and stale bots, CLA checks), downloading an artifact and running a prebuilt binary, or a `cargo build -p rustfs` with its own cache key. `e2e-distributed.yml` and `e2e-upgrade.yml` build the server and the `e2e_test` harness on `ubuntu-latest` inside their budgets, so "it compiles something" alone is not a reason.
 
+The functional chain's `prepare` and `complete-chain` jobs, the performance runner availability check, and runner hygiene use `ubuntu-latest`: they inspect APIs or artifacts, not the lab hosts. The actual functional and performance suites remain on their lab runners. Functional-chain health collection stays on the operator-managed `smoke-testing` runner as part of the automation environment. Docker image packaging also uses `ubuntu-latest` for both musl and glibc variants; it downloads release binaries rather than compiling the workspace, and still sets up QEMU and Buildx explicitly.
+
+Moving these jobs off AKS reduces capacity demand, not necessarily the Azure bill immediately. VM costs fall only when nodes scale down or smaller capacity replaces them.
+
 A hosted runner is also the only choice for a few things the pods cannot do: `mount -o loop` and `mount -t tmpfs` fail inside the ARC pods, and a container runtime cannot guarantee that `io_uring_setup` is allowed. `uring-integration` and `e2e-distributed` are on `ubuntu-latest` for that reason, not for cost.
 
 ## Cache rule

.github/workflows/docker.yml

@@ -337,7 +337,7 @@ jobs:
     name: Build Docker Images
     needs: build-check
     if: needs.build-check.outputs.should_build == 'true'
-    runs-on: dind-sm-standard-2
+    runs-on: ubuntu-latest
     timeout-minutes: 60
     strategy:
       fail-fast: false

.github/workflows/runner-hygiene.yml

@@ -44,7 +44,7 @@ jobs:
   check-ephemerality:
     if: github.repository == 'rustfs/rustfs'
     name: Check runner ephemerality
-    runs-on: sm-standard-2
+    runs-on: ubuntu-latest
     timeout-minutes: 15
     steps:
       - name: Checkout repository

.github/workflows/rustfs-functional-chain.yml

@@ -42,7 +42,7 @@ concurrency:
 jobs:
   prepare:
     if: ${{ github.event_name == 'workflow_dispatch' || github.event.workflow_run.event == 'schedule' }}
-    runs-on: smoke-testing
+    runs-on: ubuntu-latest
     timeout-minutes: 10
     outputs:
       manifest: ${{ steps.candidate.outputs.manifest }}
@@ -188,7 +188,7 @@ jobs:
   complete-chain:
     needs: [prepare, upgrade, s3, kms, tier, storage, heal, pool, security, replication, fault-tolerance, table, performance]
     if: ${{ always() && needs.prepare.result != 'skipped' }}
-    runs-on: smoke-testing
+    runs-on: ubuntu-latest
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@f548e57e544e1ff5a4c46bf1e1b8685f8e4a348a # v7

.github/workflows/rustfs-performance-test.yml

@@ -90,7 +90,7 @@ env:
 jobs:
   runner-check:
     if: ${{ inputs.chain_manifest != '' || github.event_name == 'workflow_dispatch' || github.event_name == 'repository_dispatch' }}
-    runs-on: sm-standard-2
+    runs-on: ubuntu-latest
     timeout-minutes: 5
     steps:
       - uses: actions/checkout@f548e57e544e1ff5a4c46bf1e1b8685f8e4a348a # v7

crates/concurrency/Cargo.toml

@@ -26,7 +26,7 @@ rustfs-io-core = { workspace = true }
 serde = { workspace = true, features = ["derive"] }
 
 # Async runtime
-tokio = { workspace = true, features = ["sync", "fs", "rt-multi-thread"] }
+tokio = { workspace = true, features = ["sync", "fs", "rt-multi-thread", "time"] }
 
 # Logging
 tracing = { workspace = true }

crates/config/README.md

@@ -100,6 +100,7 @@ when restoring `/rustfs/console` for a custom OEM build.
 ## S3 API environment variables
 
 - `RUSTFS_API_OBJECT_MAX_VERSIONS` caps the number of retained versions for a single object. It defaults to `9223372036854775807`, matching MinIO's practical-unlimited default. Set a positive integer to enforce a lower per-object metadata bound.
+- `RUSTFS_VEEAM_SOSAPI_ENABLE` serves Veeam SOSAPI `system.xml` and `capacity.xml` for an authenticated GET or HEAD of those exact bucket-root keys. It defaults to `true`. Explicit version reads use the normal object path. Capacity requests return `ServiceUnavailable` until the scanner publishes a complete snapshot certified for the current bucket incarnation and authoritative quota metadata can be read. Legacy or mixed-version snapshots without an incarnation proof cannot serve capacity until a compatible scanner publishes a certified snapshot. Capacity also returns `ServiceUnavailable` when cluster or disk observations are missing, stale, or degraded. Retry after scanner convergence and storage or metadata recovery. Capacity assumes shard paths have independent backing space; shared physical storage can make the estimate optimistic. Set the flag to `false` to restore the normal object path, including deletion of a real object previously stored at that key.
 - `MINIO_API_OBJECT_MAX_VERSIONS` is accepted as a compatibility alias when the canonical RustFS variable is not set.
 
 ## Distributed endpoint locality

crates/config/src/constants/app.rs

@@ -222,6 +222,16 @@ pub const ENV_RUSTFS_TLS_PATH: &str = "RUSTFS_TLS_PATH";
 /// Environment variable for server KMS enable.
 pub const ENV_RUSTFS_KMS_ENABLE: &str = "RUSTFS_KMS_ENABLE";
 
+/// Environment variable for Veeam SOSAPI virtual system objects.
+///
+/// When true (the default), authenticated GET and HEAD of the two Veeam
+/// SOSAPI keys return generated XML. When false, those keys use the normal
+/// object path so an operator can remove a real object stored there earlier.
+pub const ENV_VEEAM_SOSAPI_ENABLE: &str = "RUSTFS_VEEAM_SOSAPI_ENABLE";
+
+/// Default Veeam SOSAPI enablement.
+pub const DEFAULT_VEEAM_SOSAPI_ENABLE: bool = true;
+
 /// Default KMS enable for server-side encryption
 /// This is the default value for enabling KMS encryption for server-side encryption.
 /// Default value: false

crates/data-usage/src/data_usage.rs

@@ -466,6 +466,9 @@ pub struct BucketTargetUsageInfo {
 #[derive(Debug, Default, Clone, Serialize, Deserialize, PartialEq, Eq)]
 pub struct BucketUsageInfo {
     pub size: u64,
+    /// Bucket identity certified by every set contributing to this snapshot.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub bucket_incarnation: Option<String>,
     // Following five fields suffixed with V1 are here for backward compatibility
     // Total Size for objects that have not yet been replicated
     pub replication_pending_size_v1: u64,
@@ -2316,6 +2319,9 @@ impl BucketUsageInfo {
     /// Add size summary to this bucket usage
     /// Merge another BucketUsageInfo into this one
     pub fn merge(&mut self, other: &BucketUsageInfo) {
+        if self.bucket_incarnation != other.bucket_incarnation {
+            self.bucket_incarnation = None;
+        }
         self.size += other.size;
         self.objects_count += other.objects_count;
         self.versions_count += other.versions_count;
@@ -3299,6 +3305,31 @@ mod tests {
         assert_eq!(usage1.versions_count, 15);
     }
 
+    #[test]
+    fn bucket_usage_merge_discards_incompatible_incarnation_proofs() {
+        let id = "00000000-0000-4000-8000-000000000001";
+        let mut same = BucketUsageInfo {
+            bucket_incarnation: Some(id.into()),
+            ..Default::default()
+        };
+        same.merge(&BucketUsageInfo {
+            bucket_incarnation: Some(id.into()),
+            ..Default::default()
+        });
+        assert_eq!(same.bucket_incarnation.as_deref(), Some(id));
+        same.merge(&BucketUsageInfo::default());
+        assert!(same.bucket_incarnation.is_none());
+        let mut different = BucketUsageInfo {
+            bucket_incarnation: Some(id.into()),
+            ..Default::default()
+        };
+        different.merge(&BucketUsageInfo {
+            bucket_incarnation: Some("00000000-0000-4000-8000-000000000002".into()),
+            ..Default::default()
+        });
+        assert!(different.bucket_incarnation.is_none());
+    }
+
     #[test]
     fn size_summary_add_saturates_instead_of_overflowing() {
         // The scanner folds one summary per object into a per-prefix total, so a

crates/e2e_test/src/list_objects_v2_pagination_test.rs

@@ -38,6 +38,8 @@ mod tests {
     use tracing::info;
 
     const PAGINATION_TIMEOUT: Duration = Duration::from_secs(120);
+    // Bound queued durable commits on the single fixture disk under CI I/O pressure.
+    const FIXTURE_PUT_CONCURRENCY: usize = 4;
 
     // Fixture population can require thousands of durable PUTs. Bound the
     // listing traversal itself with one deadline shared by every page.
@@ -564,7 +566,7 @@ mod tests {
         let object_count = 1002;
         // Finish every durable PUT before listing, with the same bounded fanout as the delimiter fixtures.
         stream::iter(0..object_count)
-            .for_each_concurrent(16, |i| {
+            .for_each_concurrent(FIXTURE_PUT_CONCURRENCY, |i| {
                 let client = &client;
                 async move {
                     let key = format!("object{i:04}.txt");
@@ -575,7 +577,7 @@ mod tests {
                         .body(ByteStream::from_static(b"test content"))
                         .send()
                         .await
-                        .unwrap_or_else(|err| panic!("Failed to put fixture object {key}: {err}"));
+                        .unwrap_or_else(|err| panic!("Failed to put fixture object {key}: {err:?}"));
                 }
             })
             .await;
@@ -822,7 +824,7 @@ mod tests {
             .flat_map(|dir| (0..10).map(move |file| format!("dir-{dir:03}/file{file:02}.txt")))
             .collect();
         stream::iter(&all_keys)
-            .for_each_concurrent(16, |key| {
+            .for_each_concurrent(FIXTURE_PUT_CONCURRENCY, |key| {
                 let client = &client;
                 async move {
                     client
@@ -832,7 +834,7 @@ mod tests {
                         .body(ByteStream::from_static(b"x"))
                         .send()
                         .await
-                        .unwrap_or_else(|err| panic!("Failed to put fixture object {key}: {err}"));
+                        .unwrap_or_else(|err| panic!("Failed to put fixture object {key}: {err:?}"));
                 }
             })
             .await;
@@ -1055,7 +1057,7 @@ mod tests {
         let files_per_dir = 100;
         let fixture_started = std::time::Instant::now();
         stream::iter((0..dir_count).flat_map(|d| (0..files_per_dir).map(move |f| (d, f))))
-            .for_each_concurrent(16, |(d, f)| {
+            .for_each_concurrent(FIXTURE_PUT_CONCURRENCY, |(d, f)| {
                 let client = &client;
                 async move {
                     let key = format!("dir-{d:02}/file{f:03}.txt");
@@ -1066,7 +1068,7 @@ mod tests {
                         .body(ByteStream::from_static(b"x"))
                         .send()
                         .await
-                        .unwrap_or_else(|err| panic!("Failed to put fixture object {key}: {err}"));
+                        .unwrap_or_else(|err| panic!("Failed to put fixture object {key}: {err:?}"));
                 }
             })
             .await;

crates/e2e_test/src/snowball_auto_extract_test.rs

@@ -261,6 +261,61 @@ mod tests {
         archive
     }
 
+    #[tokio::test]
+    async fn snowball_auto_extract_rejects_veeam_virtual_members() -> Result<(), Box<dyn Error + Send + Sync>> {
+        init_logging();
+        let mut env = RustFSTestEnvironment::new().await?;
+        env.start_rustfs_server_with_env(vec![], &[("RUSTFS_VEEAM_SOSAPI_ENABLE", "true")])
+            .await?;
+        let client = env.create_s3_client();
+        let bucket = "snowball-veeam-reserved";
+        client.create_bucket().bucket(bucket).send().await?;
+        let prefix = ".system-d26a9498-cb7c-4a87-a44a-8ae204f5ba6c";
+        for (member, destination, use_prefix) in [
+            (format!("{prefix}/system.xml"), format!("{prefix}/system.xml"), false),
+            ("capacity.xml".to_string(), format!("{prefix}/capacity.xml"), true),
+        ] {
+            let mut builder = tokio_tar::Builder::new(Cursor::new(Vec::new()));
+            append_typed_entry(&mut builder, &member, tokio_tar::EntryType::Regular, b"blocked").await?;
+            let archive = builder.into_inner().await?.into_inner();
+            let mut request = client
+                .put_object()
+                .bucket(bucket)
+                .key("fixture.tar")
+                .metadata("Snowball-Auto-Extract", "true")
+                .body(ByteStream::from(archive));
+            if use_prefix {
+                request = request
+                    .metadata("Minio-Snowball-Prefix", prefix)
+                    .metadata("Minio-Snowball-Ignore-Errors", "true");
+            }
+            let error = request.send().await.expect_err("virtual archive members must be rejected");
+            assert_eq!(error.code(), Some("MethodNotAllowed"));
+            let listed = client.list_objects_v2().bucket(bucket).prefix(&destination).send().await?;
+            assert!(listed.contents().is_empty(), "rejected virtual member must not be stored");
+        }
+        let mut builder = tokio_tar::Builder::new(Cursor::new(Vec::new()));
+        append_typed_entry(&mut builder, "ordinary.xml", tokio_tar::EntryType::Regular, b"ordinary").await?;
+        client
+            .put_object()
+            .bucket(bucket)
+            .key("fixture.tar")
+            .metadata("Snowball-Auto-Extract", "true")
+            .metadata("Minio-Snowball-Prefix", prefix)
+            .body(ByteStream::from(builder.into_inner().await?.into_inner()))
+            .send()
+            .await?;
+        let ordinary = client
+            .get_object()
+            .bucket(bucket)
+            .key(format!("{prefix}/ordinary.xml"))
+            .send()
+            .await?;
+        assert_eq!(ordinary.body.collect().await?.into_bytes().as_ref(), b"ordinary");
+        env.stop_server();
+        Ok(())
+    }
+
     #[tokio::test]
     async fn snowball_auto_extract_supports_minio_prefix_and_directory_markers() -> Result<(), Box<dyn Error + Send + Sync>> {
         init_logging();

crates/e2e_test/src/version_id_regression_test.rs

@@ -600,6 +600,154 @@ mod tests {
         info!("✅ PASSED: Veeam backup workflow simulation completed successfully");
     }
 
+    /// Veeam B&R discovers SOSAPI by GET/HEAD of two well-known keys.
+    #[tokio::test]
+    async fn test_veeam_sosapi_system_and_capacity() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
+        use crate::common::local_http_client;
+
+        const SYSTEM_KEY: &str = ".system-d26a9498-cb7c-4a87-a44a-8ae204f5ba6c/system.xml";
+        const CAPACITY_KEY: &str = ".system-d26a9498-cb7c-4a87-a44a-8ae204f5ba6c/capacity.xml";
+
+        init_logging();
+        info!("🧪 TEST: Veeam SOSAPI system.xml and capacity.xml");
+
+        let mut env = RustFSTestEnvironment::new().await?;
+        env.start_rustfs_server_with_env(vec![], crate::common::FAST_DATA_USAGE_SCANNER_ENV)
+            .await?;
+        let client = create_s3_client(&env);
+        let bucket = "veeam-sosapi";
+        create_bucket(&client, bucket).await?;
+
+        let system = client.get_object().bucket(bucket).key(SYSTEM_KEY).send().await?;
+        let system_etag = system.e_tag().map(str::to_string);
+        let system_len = system.content_length();
+        assert_eq!(system.content_type(), Some("application/xml"));
+        let system_body = system.body.collect().await?.into_bytes();
+        let system_xml = std::str::from_utf8(&system_body)?;
+        assert!(system_xml.contains("<ProtocolVersion>\"1.0\"</ProtocolVersion>"), "{system_xml}");
+        assert!(
+            system_xml.contains("<ModelName>\"RustFS ") && system_xml.contains("\"</ModelName>"),
+            "{system_xml}"
+        );
+        assert!(system_xml.contains("<CapacityInfo>true</CapacityInfo>"));
+        assert!(system_xml.contains("<UploadSessions>false</UploadSessions>"));
+        assert!(system_xml.contains("<IAMSTS>false</IAMSTS>"));
+        assert!(!system_xml.contains("SystemRecommendations"));
+        assert!(!system_xml.contains("APIEndpoints"));
+        assert!(!system_xml.contains("&quot;"));
+
+        let head = client.head_object().bucket(bucket).key(SYSTEM_KEY).send().await?;
+        assert_eq!(head.content_type(), Some("application/xml"));
+        assert_eq!(head.content_length(), system_len);
+        assert_eq!(head.e_tag().map(str::to_string), system_etag);
+        assert!(head.last_modified().is_some());
+
+        let ranged = client
+            .get_object()
+            .bucket(bucket)
+            .key(SYSTEM_KEY)
+            .range("bytes=0-3")
+            .send()
+            .await?;
+        assert_eq!(ranged.content_length(), Some(4));
+        let ranged_header = ranged.content_range().unwrap_or("");
+        assert!(ranged_header.starts_with("bytes 0-3/"), "{ranged_header}");
+        let ranged_body = ranged.body.collect().await?.into_bytes();
+        assert_eq!(&ranged_body[..], &system_body[..4]);
+
+        let capacity = tokio::time::timeout(std::time::Duration::from_secs(180), async {
+            loop {
+                match client.get_object().bucket(bucket).key(CAPACITY_KEY).send().await {
+                    Ok(capacity) => break Ok(capacity),
+                    Err(err) if err.code() == Some("ServiceUnavailable") => {
+                        tokio::time::sleep(std::time::Duration::from_secs(2)).await;
+                    }
+                    Err(err) => break Err(err),
+                }
+            }
+        })
+        .await??;
+        assert_eq!(capacity.content_type(), Some("application/xml"));
+        let capacity_body = capacity.body.collect().await?.into_bytes();
+        let capacity_xml = std::str::from_utf8(&capacity_body)?;
+        let capacity_value = xml_u64(capacity_xml, "Capacity")?;
+        let available_value = xml_u64(capacity_xml, "Available")?;
+        let used_value = xml_u64(capacity_xml, "Used")?;
+        assert!(used_value <= capacity_value, "{capacity_xml}");
+        assert!(available_value <= capacity_value.saturating_sub(used_value), "{capacity_xml}");
+
+        let put_err = client
+            .put_object()
+            .bucket(bucket)
+            .key(SYSTEM_KEY)
+            .body(ByteStream::from_static(b"overwrite"))
+            .send()
+            .await
+            .expect_err("SOSAPI put must fail");
+        assert_eq!(put_err.code(), Some("MethodNotAllowed"));
+        let delete_err = client
+            .delete_object()
+            .bucket(bucket)
+            .key(CAPACITY_KEY)
+            .send()
+            .await
+            .expect_err("SOSAPI delete must fail");
+        assert_eq!(delete_err.code(), Some("MethodNotAllowed"));
+
+        let normal_key = "Veeam/Backup/job.dat";
+        client
+            .put_object()
+            .bucket(bucket)
+            .key(normal_key)
+            .body(ByteStream::from_static(b"backup-bytes"))
+            .send()
+            .await?;
+        let normal = client.get_object().bucket(bucket).key(normal_key).send().await?;
+        let normal_body = normal.body.collect().await?.into_bytes();
+        assert_eq!(&normal_body[..], b"backup-bytes");
+
+        let anon = local_http_client()
+            .get(format!("{}/{bucket}/{SYSTEM_KEY}", env.url))
+            .send()
+            .await?;
+        assert_eq!(anon.status(), reqwest::StatusCode::FORBIDDEN);
+        let anon_body = anon.text().await?;
+        assert!(!anon_body.contains("ProtocolVersion"), "{anon_body}");
+
+        let now = time::OffsetDateTime::now_utc();
+        let scope_date = format!("{:04}{:02}{:02}", now.year(), u8::from(now.month()), now.day());
+        let amz_date = format!("{scope_date}T{:02}{:02}{:02}Z", now.hour(), now.minute(), now.second());
+        let bad = local_http_client()
+            .get(format!("{}/{bucket}/{SYSTEM_KEY}", env.url))
+            .header("x-amz-date", &amz_date)
+            .header("x-amz-content-sha256", "UNSIGNED-PAYLOAD")
+            .header(
+                "authorization",
+                format!(
+                    "AWS4-HMAC-SHA256 Credential=bad/{scope_date}/us-east-1/s3/aws4_request, SignedHeaders=host;x-amz-content-sha256;x-amz-date, Signature=0000000000000000000000000000000000000000000000000000000000000000"
+                ),
+            )
+            .send()
+            .await?;
+        assert_eq!(bad.status(), reqwest::StatusCode::FORBIDDEN);
+        let bad_body = bad.text().await?;
+        assert!(!bad_body.contains("ProtocolVersion"), "{bad_body}");
+
+        info!("✅ PASSED: Veeam SOSAPI system.xml and capacity.xml");
+        Ok(())
+    }
+
+    fn xml_u64(xml: &str, element: &str) -> Result<u64, Box<dyn std::error::Error + Send + Sync>> {
+        let start = format!("<{element}>");
+        let end = format!("</{element}>");
+        let start_idx = xml.find(&start).ok_or_else(|| format!("missing {element} in {xml}"))? + start.len();
+        let end_idx = xml[start_idx..]
+            .find(&end)
+            .ok_or_else(|| format!("unclosed {element} in {xml}"))?
+            + start_idx;
+        Ok(xml[start_idx..end_idx].parse()?)
+    }
+
     #[tokio::test]
     async fn test_terraform_put_after_delete() -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
         init_logging();

crates/ecstore/src/api/mod.rs

@@ -252,7 +252,7 @@ pub mod bucket {
     pub mod quota {
         pub use crate::bucket::quota::{
             BucketQuota, QUOTA_RESERVATION_PROTOCOL_V1, QUOTA_RESERVATION_PROTOCOL_V2, QuotaCheckResult, QuotaError,
-            QuotaMigrationSkipReason, QuotaOperation, QuotaProtocolMigration,
+            QuotaMigrationSkipReason, QuotaOperation, QuotaProtocolMigration, QuotaType,
         };
 
         pub mod checker {
@@ -371,6 +371,15 @@ pub mod compression {
 
 pub mod config {
     pub mod com {
+        /// Preserve empty existing objects so callers can distinguish corruption from absence.
+        pub async fn read_config_preserve_empty_with_metadata_opts(
+            api: std::sync::Arc<crate::store::ECStore>,
+            file: &str,
+            opts: &crate::object_api::ObjectOptions,
+        ) -> crate::error::Result<(Vec<u8>, crate::object_api::ObjectInfo)> {
+            crate::config::com::read_config_preserve_empty_with_metadata_opts(api, file, opts).await
+        }
+
         pub use crate::config::com::{
             COMMA_SEPARATED_LISTS, CONFIG_PREFIX, ENV_CONFIG_RECOVER_ON_CORRUPTION, STORAGE_CLASS_SUB_SYS,
             ServerConfigCorruptError, ServerConfigSaveResult, ServerConfigSnapshot, delete_config, delete_config_no_lock,
@@ -416,9 +425,10 @@ pub mod data_usage {
         DATA_USAGE_CACHE_NAME, apply_bucket_usage_memory_overlay, compute_bucket_usage,
         init_compression_total_memory_from_backend, invalidate_admin_data_usage_snapshot_cache,
         invalidate_data_usage_snapshot_cache, live_bucket_usage_computations, load_admin_data_usage_from_backend_cached,
-        load_compression_total_from_memory, load_data_usage_from_backend, load_data_usage_from_backend_cached, quota_object_size,
-        record_bucket_delete_marker_memory, record_bucket_object_delete_memory, record_bucket_object_version_write_memory,
-        record_bucket_object_write_memory, record_bucket_object_write_unknown_previous_memory, record_compression_total_memory,
+        load_bucket_usage_from_backend_cached, load_compression_total_from_memory, load_data_usage_from_backend,
+        load_data_usage_from_backend_cached, quota_object_size, record_bucket_delete_marker_memory,
+        record_bucket_object_delete_memory, record_bucket_object_version_write_memory, record_bucket_object_write_memory,
+        record_bucket_object_write_unknown_previous_memory, record_compression_total_memory,
         refresh_bucket_usage_from_object_layer, refresh_versioned_bucket_usage_from_object_layer,
         remove_bucket_usage_from_backend, replace_bucket_usage_memory_from_info, store_compression_total_in_backend,
         store_data_usage_in_backend,

crates/ecstore/src/bucket/lifecycle/bucket_lifecycle_ops.rs

@@ -1086,8 +1086,9 @@ impl ExpiryState {
         }))
     }
 
-    #[cfg(test)]
-    fn new_with_unconsumed_worker_channel(capacity: usize) -> Arc<RwLock<Self>> {
+    #[cfg(any(test, feature = "test-util"))]
+    #[doc(hidden)]
+    pub fn new_with_unconsumed_worker_channel(capacity: usize) -> Arc<RwLock<Self>> {
         let (tx, rx) = mpsc::channel(capacity);
         Arc::new(RwLock::new(Self {
             tasks_tx: vec![tx],
@@ -3516,13 +3517,21 @@ async fn stale_upload_current_size_with_opts(
         .await
         .ok()?;
 
-    Some(
-        parts
-            .parts
-            .iter()
-            .map(|part| part.actual_size.max(part.size as i64).max(0) as usize)
-            .sum(),
-    )
+    stale_upload_size_from_parts(&parts)
+}
+
+fn stale_upload_size_from_parts(parts: &crate::storage_api_contracts::multipart::ListPartsInfo) -> Option<usize> {
+    if parts.is_truncated {
+        return None;
+    }
+    parts.parts.iter().try_fold(0usize, |total, part| {
+        // ListParts represents a quorum-confirmed missing part with an empty ETag.
+        if part.etag.as_deref().is_none_or(str::is_empty) {
+            return None;
+        }
+        let actual_size = usize::try_from(part.actual_size.max(0)).ok()?;
+        total.checked_add(part.size.max(actual_size))
+    })
 }
 
 async fn stale_upload_lifecycle_due(
@@ -3539,18 +3548,43 @@ async fn stale_upload_lifecycle_due(
     let bucket = metadata.get(RUSTFS_MULTIPART_BUCKET_KEY)?;
     let object = metadata.get(RUSTFS_MULTIPART_OBJECT_KEY)?;
 
-    let lifecycle = match metadata_boundary::get_lifecycle_config(bucket).await {
+    let mut lifecycle = match metadata_boundary::get_lifecycle_config(bucket).await {
         Ok((lifecycle, _)) => lifecycle,
         Err(_) => return None,
     };
 
+    let has_size_filter = |filter: &s3s::dto::LifecycleRuleFilter| {
+        filter.object_size_greater_than.is_some()
+            || filter.object_size_less_than.is_some()
+            || filter
+                .and
+                .as_ref()
+                .is_some_and(|and| and.object_size_greater_than.is_some() || and.object_size_less_than.is_some())
+    };
+    let needs_size = lifecycle
+        .rules
+        .iter()
+        .any(|rule| rule.abort_incomplete_multipart_upload.is_some() && rule.filter.as_ref().is_some_and(has_size_filter));
+    let size = if needs_size {
+        match stale_upload_current_size_with_opts(set, metadata, upload_dir, no_lock).await {
+            Some(size) => size,
+            None => {
+                // An unknown size cannot authorize a size-filtered abort.
+                // Unrelated rules can still be evaluated independently.
+                lifecycle
+                    .rules
+                    .retain(|rule| !rule.filter.as_ref().is_some_and(has_size_filter));
+                0
+            }
+        }
+    } else {
+        0
+    };
     let object_opts = ObjectOpts {
         name: object.clone(),
         user_tags: metadata.get(AMZ_OBJECT_TAGGING).cloned().unwrap_or_default(),
         mod_time: Some(initiated),
-        size: stale_upload_current_size_with_opts(set, metadata, upload_dir, no_lock)
-            .await
-            .unwrap_or_default(),
+        size,
         is_latest: true,
         delete_marker: false,
         user_defined: metadata.clone(),
@@ -3803,7 +3837,8 @@ async fn cleanup_stale_multipart_uploads_in_set(set: &Arc<SetDisks>, now: Offset
     for candidate in candidates.into_values() {
         let upload_dir = candidate.path.rsplit('/').next().unwrap_or_default().to_string();
         let mut due = stale_upload_default_due(candidate.initiated, default_expiry);
-        if let Some(metadata) = candidate.metadata.as_ref()
+        if now < due
+            && let Some(metadata) = candidate.metadata.as_ref()
             && let Some(lifecycle_due) = stale_upload_lifecycle_due(set, metadata, candidate.initiated, &upload_dir, false).await
             && lifecycle_due < due
         {
@@ -3832,8 +3867,9 @@ async fn cleanup_stale_multipart_uploads_in_set(set: &Arc<SetDisks>, now: Offset
         let current_metadata = cleanup_guard.file_info().metadata.clone();
         let current_initiated = initiated_from_upload_dir(&upload_dir, cleanup_guard.file_info().mod_time);
         let mut current_due = stale_upload_default_due(current_initiated, default_expiry);
-        if let Some(lifecycle_due) =
-            stale_upload_lifecycle_due(set, &current_metadata, current_initiated, &upload_dir, true).await
+        if now < current_due
+            && let Some(lifecycle_due) =
+                stale_upload_lifecycle_due(set, &current_metadata, current_initiated, &upload_dir, true).await
             && lifecycle_due < current_due
         {
             current_due = lifecycle_due;
@@ -15868,6 +15904,261 @@ mod tests {
         assert!(ecstore.is_ok(), "fresh local ECStore boot should succeed, got {ecstore:?}");
     }
 
+    #[tokio::test(flavor = "current_thread")]
+    #[serial]
+    async fn stale_multipart_cleanup_preserves_partial_metadata_without_upload_part_warning() {
+        use tracing::instrument::WithSubscriber as _;
+        #[derive(Clone, Default)]
+        struct CapturedLogs(Arc<StdMutex<Vec<u8>>>);
+        struct LogWriter(Arc<StdMutex<Vec<u8>>>);
+        impl std::io::Write for LogWriter {
+            fn write(&mut self, bytes: &[u8]) -> std::io::Result<usize> {
+                self.0.lock().unwrap().extend_from_slice(bytes);
+                Ok(bytes.len())
+            }
+            fn flush(&mut self) -> std::io::Result<()> {
+                Ok(())
+            }
+        }
+        impl<'a> tracing_subscriber::fmt::MakeWriter<'a> for CapturedLogs {
+            type Writer = LogWriter;
+            fn make_writer(&'a self) -> Self::Writer {
+                LogWriter(self.0.clone())
+            }
+        }
+
+        let (paths, ecstore) = setup_test_env().await;
+        let bucket = format!("stale-partial-{}", Uuid::new_v4().simple());
+        create_test_bucket(&ecstore, &bucket).await;
+        for copies in [1, 2] {
+            let object = format!("partial-{copies}.bin");
+            let initiated = OffsetDateTime::now_utc() - time::Duration::hours(30);
+            let upload = ecstore
+                .new_multipart_upload(
+                    &bucket,
+                    &object,
+                    &ObjectOptions {
+                        mod_time: Some(initiated),
+                        max_parity: true,
+                        ..Default::default()
+                    },
+                )
+                .await
+                .expect("multipart upload should be created");
+            let decoded = base64_simd::URL_SAFE_NO_PAD
+                .decode_to_vec(upload.upload_id.as_bytes())
+                .unwrap();
+            let decoded = String::from_utf8(decoded).unwrap();
+            let (_, upload_dir) = decoded.split_once('.').expect("deployment-prefixed upload id");
+            let upload_path = format!("{}/{upload_dir}", multipart_sha_dir(&bucket, &object));
+            let physical_paths: Vec<_> = paths
+                .iter()
+                .map(|path| path.join(RUSTFS_META_MULTIPART_BUCKET).join(&upload_path))
+                .collect();
+            let original: Vec<_> = physical_paths
+                .iter()
+                .take(copies)
+                .map(|path| std::fs::read(path.join(STORAGE_FORMAT_FILE)).unwrap())
+                .collect();
+            let info = super::get_file_info(
+                &original[0],
+                RUSTFS_META_MULTIPART_BUCKET,
+                &upload_path,
+                "",
+                super::FileInfoOpts {
+                    data: false,
+                    include_free_versions: false,
+                    include_part_checksums: false,
+                },
+            )
+            .unwrap();
+            assert_eq!((info.erasure.data_blocks, info.erasure.parity_blocks), (2, 2));
+            for path in physical_paths.iter().skip(copies) {
+                fs::remove_dir_all(path).await.expect("remove selected metadata copies");
+            }
+            if copies == 2 {
+                ecstore
+                    .get_multipart_info(&bucket, &object, &upload.upload_id, &ObjectOptions::default())
+                    .await
+                    .expect("two metadata copies must meet read quorum");
+            }
+
+            let logs = CapturedLogs::default();
+            let subscriber = tracing_subscriber::fmt()
+                .with_max_level(tracing::Level::DEBUG)
+                .with_writer(logs.clone())
+                .with_ansi(false)
+                .without_time()
+                .finish();
+            cleanup_stale_multipart_uploads_once_at(
+                ecstore.clone(),
+                OffsetDateTime::now_utc(),
+                StdDuration::from_secs(24 * 60 * 60),
+            )
+            .with_subscriber(subscriber)
+            .await;
+
+            for (path, expected) in physical_paths.iter().zip(&original) {
+                assert_eq!(fs::read(path.join(STORAGE_FORMAT_FILE)).await.unwrap(), *expected);
+            }
+            let log_output = String::from_utf8(logs.0.lock().unwrap().clone()).unwrap();
+            assert!(
+                log_output.contains(&upload_path),
+                "missing background diagnostic for {upload_path}: {log_output}"
+            );
+            assert!(log_output.contains("multipart_cleanup_lock_or_recheck_failed"), "{log_output}");
+            assert!(!log_output.contains("op=\"upload_part\""), "unexpected upload-part warning: {log_output}");
+            for path in physical_paths.iter().take(copies) {
+                fs::remove_dir_all(path).await.unwrap();
+            }
+        }
+    }
+
+    #[tokio::test(flavor = "current_thread")]
+    #[serial]
+    async fn stale_multipart_cleanup_lists_parts_only_when_size_is_needed() {
+        use std::sync::atomic::{AtomicUsize, Ordering};
+        use tracing::instrument::WithSubscriber as _;
+        use tracing_subscriber::prelude::*;
+
+        struct PartListCounter(Arc<AtomicUsize>);
+        impl<S: tracing::Subscriber> tracing_subscriber::Layer<S> for PartListCounter {
+            fn on_new_span(
+                &self,
+                attrs: &tracing::span::Attributes<'_>,
+                _id: &tracing::span::Id,
+                _ctx: tracing_subscriber::layer::Context<'_, S>,
+            ) {
+                if attrs.metadata().name() == "list_object_parts" {
+                    self.0.fetch_add(1, Ordering::Relaxed);
+                }
+            }
+        }
+
+        let (_, ecstore) = setup_test_env().await;
+        let bucket = format!("stale-list-parts-{}", Uuid::new_v4().simple());
+        create_test_bucket(&ecstore, &bucket).await;
+        set_abort_incomplete_lifecycle(&bucket, "logs/", 0).await;
+        let now = OffsetDateTime::now_utc();
+        for (object, age, size_filter, should_list) in [
+            ("logs/default-expired", time::Duration::hours(30), false, false),
+            ("logs/lifecycle-only", time::Duration::minutes(5), false, false),
+            ("logs/size-filter", time::Duration::minutes(5), true, true),
+        ] {
+            if size_filter {
+                set_abort_incomplete_lifecycle_with_size(&bucket, "logs/", 0, 0).await;
+            }
+            let upload = ecstore
+                .new_multipart_upload(
+                    &bucket,
+                    object,
+                    &ObjectOptions {
+                        mod_time: Some(now - age),
+                        ..Default::default()
+                    },
+                )
+                .await
+                .expect("create multipart upload");
+            if size_filter {
+                let mut data = PutObjReader::from_vec(vec![1, 2, 3, 4]);
+                ecstore
+                    .put_object_part(&bucket, object, &upload.upload_id, 1, &mut data, &ObjectOptions::default())
+                    .await
+                    .expect("upload a part for size filtering");
+            }
+            let calls = Arc::new(AtomicUsize::new(0));
+            let subscriber = tracing_subscriber::registry().with(PartListCounter(Arc::clone(&calls)));
+            cleanup_stale_multipart_uploads_once_at(ecstore.clone(), now, StdDuration::from_secs(24 * 60 * 60))
+                .with_subscriber(subscriber)
+                .await;
+            let listed = calls.load(Ordering::Relaxed);
+            assert_eq!(listed > 0, should_list, "unexpected ListParts calls for {object}: {listed}");
+            let result = ecstore
+                .get_multipart_info(&bucket, object, &upload.upload_id, &ObjectOptions::default())
+                .await;
+            assert!(
+                matches!(result, Err(ref err) if is_err_invalid_upload_id(err)),
+                "upload must be removed: {result:?}"
+            );
+        }
+    }
+
+    #[test]
+    fn stale_multipart_cleanup_rejects_incomplete_or_overflowing_part_sizes() {
+        use crate::storage_api_contracts::multipart::{ListPartsInfo, PartInfo};
+
+        let part = |size, actual_size, etag: &str| PartInfo {
+            size,
+            actual_size,
+            etag: Some(etag.to_owned()),
+            ..Default::default()
+        };
+        let mut parts = ListPartsInfo {
+            parts: vec![part(4, 6, "valid")],
+            ..Default::default()
+        };
+        assert_eq!(super::stale_upload_size_from_parts(&parts), Some(6));
+        parts.is_truncated = true;
+        assert_eq!(super::stale_upload_size_from_parts(&parts), None);
+        parts.is_truncated = false;
+        parts.parts = vec![part(0, 0, "")];
+        assert_eq!(super::stale_upload_size_from_parts(&parts), None);
+        parts.parts = vec![part(usize::MAX, 0, "valid"), part(1, 1, "valid")];
+        assert_eq!(super::stale_upload_size_from_parts(&parts), None);
+    }
+
+    #[tokio::test]
+    #[serial]
+    async fn stale_multipart_cleanup_handles_unknown_size_without_false_abort() {
+        let (_, ecstore) = setup_test_env().await;
+        let bucket = format!("stale-unknown-size-{}", Uuid::new_v4().simple());
+        let object = "logs/object";
+        create_test_bucket(&ecstore, &bucket).await;
+        let size_rule = r#"<Rule><ID>size</ID><Status>Enabled</Status><Filter><ObjectSizeLessThan>5</ObjectSizeLessThan></Filter><AbortIncompleteMultipartUpload><DaysAfterInitiation>0</DaysAfterInitiation></AbortIncompleteMultipartUpload></Rule>"#;
+        let independent_rule = r#"<Rule><ID>prefix</ID><Status>Enabled</Status><Filter><Prefix>logs/</Prefix></Filter><AbortIncompleteMultipartUpload><DaysAfterInitiation>0</DaysAfterInitiation></AbortIncompleteMultipartUpload></Rule>"#;
+        let lifecycle = |rules: &str| format!("<LifecycleConfiguration>{rules}</LifecycleConfiguration>").into_bytes();
+        metadata_sys::update(&bucket, BUCKET_LIFECYCLE_CONFIG, lifecycle(size_rule))
+            .await
+            .expect("install upper-size lifecycle rule");
+        let metadata = HashMap::from([
+            (super::RUSTFS_MULTIPART_BUCKET_KEY.to_owned(), bucket.clone()),
+            (super::RUSTFS_MULTIPART_OBJECT_KEY.to_owned(), object.to_owned()),
+        ]);
+        let initiated = OffsetDateTime::now_utc() - time::Duration::hours(1);
+        let set = &ecstore.pools[0].disk_set[0];
+        let upload = ecstore
+            .new_multipart_upload(&bucket, object, &ObjectOptions::default())
+            .await
+            .expect("create empty multipart upload");
+        let decoded = base64_simd::URL_SAFE_NO_PAD
+            .decode_to_vec(upload.upload_id.as_bytes())
+            .expect("decode upload ID");
+        let decoded = String::from_utf8(decoded).expect("upload ID must be UTF-8");
+        let (_, upload_dir) = decoded.split_once('.').expect("deployment-prefixed upload ID");
+        assert!(
+            super::stale_upload_lifecycle_due(set, &metadata, initiated, upload_dir, false)
+                .await
+                .is_some(),
+            "a known empty upload must match the upper-size rule"
+        );
+        let missing_upload = format!("{}x{}", Uuid::new_v4(), initiated.unix_timestamp_nanos());
+        assert!(
+            super::stale_upload_lifecycle_due(set, &metadata, initiated, &missing_upload, false)
+                .await
+                .is_none(),
+            "an unreadable size must not match the upper-size rule"
+        );
+        metadata_sys::update(&bucket, BUCKET_LIFECYCLE_CONFIG, lifecycle(&format!("{size_rule}{independent_rule}")))
+            .await
+            .expect("install size-independent lifecycle rule");
+        assert!(
+            super::stale_upload_lifecycle_due(set, &metadata, initiated, &missing_upload, false)
+                .await
+                .is_some(),
+            "a size-independent rule remains eligible when size is unknown"
+        );
+    }
+
     #[tokio::test]
     #[serial]
     async fn stale_multipart_cleanup_uses_default_expiry_without_lifecycle() {

crates/ecstore/src/bucket/lifecycle/metadata_boundary.rs

@@ -63,14 +63,7 @@ pub(crate) async fn get_expiry_configs_for_options(
     bucket: &str,
     opts: &crate::object_api::ObjectOptions,
 ) -> Result<LifecycleExpiryConfigs> {
-    let bucket_incarnation_id = match opts
-        .object_lock_config_snapshot
-        .as_ref()
-        .and_then(|snapshot| snapshot.validated_bucket_incarnation_for(api.id, bucket, opts.expected_bucket_incarnation_id))
-    {
-        Some(incarnation_id) => incarnation_id,
-        None => metadata_sys::get_bucket_incarnation_id_for_options_in(&api.ctx, bucket, opts).await?,
-    };
+    let bucket_incarnation_id = metadata_sys::get_bucket_incarnation_id_for_options_in(&api.ctx, bucket, opts).await?;
     let metadata = get_authoritative_metadata(api, bucket, bucket_incarnation_id).await?;
     let table_bucket_enabled = metadata.table_bucket_enabled();
 

crates/ecstore/src/bucket/metadata_sys.rs

@@ -564,12 +564,39 @@ pub(crate) async fn validate_bucket_reconstruction_in(
     Ok(())
 }
 
-/// Validate against disk while retaining an already-held Object Lock fence.
+/// Resolve the authoritative bucket incarnation id for `opts`:
+/// 1. When namespace locking is enabled and `opts.object_lock_config_snapshot` is
+///    present, validate and return the snapshot's incarnation under its held
+///    lifecycle and metadata-transaction fences.
+/// 2. When namespace locking is enabled and `opts.bucket_lifecycle_lock_fence` is
+///    present and not lost, reuse the store's `BucketFenceRegistry` memo if a
+///    registered lifecycle read guard is currently held without lock loss.
+/// 3. Otherwise, acquire the bucket metadata transaction read lock (unless
+///    already held on `opts`) and read the incarnation from disk.
 pub(crate) async fn get_bucket_incarnation_id_for_options_in(
     ctx: &crate::runtime::instance::InstanceContext,
     bucket: &str,
     opts: &ObjectOptions,
 ) -> Result<Uuid> {
+    if !ctx.lock_manager().is_disabled() {
+        if let Some(snapshot) = opts.object_lock_config_snapshot.as_ref() {
+            let store = object_store_in(ctx).await?;
+            return snapshot
+                .validated_bucket_incarnation_for(store.id, bucket, opts.expected_bucket_incarnation_id)
+                .ok_or_else(|| {
+                    Error::other("Object Lock snapshot does not hold a valid metadata transaction fence for this bucket")
+                });
+        }
+        if opts
+            .bucket_lifecycle_lock_fence
+            .as_ref()
+            .is_some_and(|fence| !fence.is_lock_lost())
+            && let Some(store) = object_store_if_initialized_in(ctx).await
+            && let Some(incarnation) = store.bucket_fence_registry.validated_incarnation(bucket)
+        {
+            return Ok(incarnation);
+        }
+    }
     let sys = bucket_metadata_sys_of(ctx)?;
     let sys = sys.read().await.clone();
     let guard = acquire_bucket_metadata_transaction_read_lock_for_options_in(ctx, bucket, opts).await?;

crates/ecstore/src/config/com.rs

@@ -488,6 +488,18 @@ where
     Ok(data)
 }
 
+/// Read config bytes and metadata while preserving an existing empty payload.
+pub(crate) async fn read_config_preserve_empty_with_metadata_opts<S>(
+    api: Arc<S>,
+    file: &str,
+    opts: &ObjectOptions,
+) -> Result<(Vec<u8>, ObjectInfo)>
+where
+    S: EcstoreObjectIO,
+{
+    read_config_with_metadata_inner(api, file, opts, true, None).await
+}
+
 pub async fn read_config_no_lock<S>(api: Arc<S>, file: &str) -> Result<Vec<u8>>
 where
     S: ObjectIO<

crates/ecstore/src/data_usage/mod.rs

@@ -1493,6 +1493,48 @@ pub async fn load_data_usage_from_backend_cached(store: Arc<ECStore>) -> Result<
     project_data_usage_from_backend_cached(store, DataUsageInfo::clone).await
 }
 
+/// Read one bucket's persisted usage without cloning the complete snapshot.
+pub async fn load_bucket_usage_from_backend_cached(
+    store: Arc<ECStore>,
+    bucket: &str,
+    incarnation: uuid::Uuid,
+) -> Result<Option<u64>, Error> {
+    project_data_usage_from_backend_cached(store, |info| certified_bucket_usage(info, bucket, incarnation)).await
+}
+
+fn certified_bucket_usage(info: &DataUsageInfo, bucket: &str, incarnation: uuid::Uuid) -> Option<u64> {
+    if incarnation.is_nil()
+        || !info.is_complete_bucket_usage_snapshot()
+        || info.usage_snapshot_observational
+        || info.scanner_cycle.is_none()
+        || info.scanner_epoch.is_none()
+    {
+        return None;
+    }
+    let pending_count = u64::try_from(info.usage_snapshot_pending_buckets.len()).ok()?;
+    if pending_count != info.usage_snapshot_pending_bucket_count {
+        return None;
+    }
+    match info.usage_snapshot_converged {
+        Some(true) if pending_count == 0 => {}
+        Some(false)
+            if pending_count > 0
+                && info.usage_snapshot_pending_buckets.windows(2).all(|pair| pair[0] < pair[1])
+                && info
+                    .usage_snapshot_pending_buckets
+                    .binary_search_by(|pending| pending.as_str().cmp(bucket))
+                    .is_err() => {}
+        _ => return None,
+    }
+    let usage = info.buckets_usage.get(bucket)?;
+    let certified = usage
+        .bucket_incarnation
+        .as_deref()
+        .and_then(|id| uuid::Uuid::parse_str(id).ok())
+        .filter(|id| !id.is_nil())?;
+    (certified == incarnation).then_some(usage.size)
+}
+
 // Project under the cache guard so scalar readers never copy the snapshot's
 // bucket maps. The owned API shares the same TTL, refresh and invalidation path.
 async fn project_data_usage_from_backend_cached<T>(

crates/ecstore/src/data_usage/tests/snapshot_projection.rs

@@ -129,6 +129,41 @@ fn projected_publication_moves_bucket_maps_into_cache() {
     );
 }
 
+#[test]
+fn certified_bucket_usage_rejects_unproven_and_pending_data() {
+    let id = uuid::Uuid::from_u128(7);
+    let mut info = data_usage_info_for_test("known", 1, 42, SystemTime::UNIX_EPOCH);
+    info.usage_snapshot_converged = Some(true);
+    info.scanner_cycle = Some(1);
+    info.scanner_epoch = Some(1);
+    info.buckets_usage.get_mut("known").unwrap().bucket_incarnation = Some(id.to_string());
+    assert_eq!(certified_bucket_usage(&info, "known", id), Some(42));
+    assert_eq!(certified_bucket_usage(&info, "known", uuid::Uuid::from_u128(8)), None);
+    assert_eq!(certified_bucket_usage(&info, "known", uuid::Uuid::nil()), None);
+    let mut legacy = info.clone();
+    legacy.buckets_usage.get_mut("known").unwrap().bucket_incarnation = None;
+    assert_eq!(certified_bucket_usage(&legacy, "known", id), None);
+    legacy.buckets_usage.get_mut("known").unwrap().bucket_incarnation = Some("corrupt".into());
+    assert_eq!(certified_bucket_usage(&legacy, "known", id), None);
+    let mut pending = info.clone();
+    pending.usage_snapshot_converged = Some(false);
+    pending.usage_snapshot_pending_buckets = vec!["other".into()];
+    pending.usage_snapshot_pending_bucket_count = 1;
+    assert_eq!(certified_bucket_usage(&pending, "known", id), Some(42));
+    pending.usage_snapshot_pending_buckets = vec!["known".into()];
+    assert_eq!(certified_bucket_usage(&pending, "known", id), None);
+    pending.usage_snapshot_pending_bucket_count = 0;
+    assert_eq!(certified_bucket_usage(&pending, "known", id), None);
+    pending.usage_snapshot_pending_buckets = vec!["z".into(), "a".into()];
+    pending.usage_snapshot_pending_bucket_count = 2;
+    assert_eq!(certified_bucket_usage(&pending, "known", id), None);
+    let mut observational = info.clone();
+    observational.usage_snapshot_observational = true;
+    assert_eq!(certified_bucket_usage(&observational, "known", id), None);
+    info.usage_snapshot_converged = None;
+    assert_eq!(certified_bucket_usage(&info, "known", id), None);
+}
+
 #[tokio::test]
 #[serial]
 async fn persisted_scalar_projection_shares_cache_refresh_and_invalidation() {
@@ -140,6 +175,13 @@ async fn persisted_scalar_projection_shares_cache_refresh_and_invalidation() {
     info.buckets_usage.insert("empty".to_string(), BucketUsageInfo::default());
     info.bucket_sizes.insert("empty".to_string(), 0);
     info.buckets_count = 2;
+    info.usage_snapshot_converged = Some(true);
+    info.scanner_cycle = Some(1);
+    info.scanner_epoch = Some(1);
+    let incarnation = uuid::Uuid::from_u128(7);
+    for usage in info.buckets_usage.values_mut() {
+        usage.bucket_incarnation = Some(incarnation.to_string());
+    }
     save_config(
         store.clone(),
         DATA_USAGE_OBJ_NAME_PATH.as_str(),
@@ -151,11 +193,29 @@ async fn persisted_scalar_projection_shares_cache_refresh_and_invalidation() {
 
     for (bucket, expected) in [("known", Some(42)), ("empty", Some(0)), ("missing", None)] {
         assert_eq!(persisted_bucket_usage(store.clone(), bucket).await, expected);
+        assert_eq!(
+            load_bucket_usage_from_backend_cached(store.clone(), bucket, incarnation)
+                .await
+                .expect("project bucket usage"),
+            expected
+        );
         let owned = load_data_usage_from_backend_cached(store.clone())
             .await
             .expect("owned cached snapshot");
         assert_eq!(expected, owned.buckets_usage.get(bucket).map(|usage| usage.size));
     }
+    assert_eq!(
+        load_bucket_usage_from_backend_cached(store.clone(), "known", uuid::Uuid::from_u128(8))
+            .await
+            .unwrap(),
+        None
+    );
+    assert_eq!(
+        load_bucket_usage_from_backend_cached(store.clone(), "known", uuid::Uuid::nil())
+            .await
+            .unwrap(),
+        None
+    );
     info.buckets_usage.get_mut("known").expect("known bucket").size = 84;
     info.bucket_sizes.insert("known".to_string(), 84);
     save_config(

crates/ecstore/src/disk/local.rs

@@ -8450,6 +8450,23 @@ impl LocalDisk {
                     return Err(std::io::Error::other("metadata read worker cancelled"));
                 }
                 let _io_permit = io_permit;
+                #[cfg(all(any(test, feature = "test-util"), not(windows)))]
+                {
+                    let opened = root.open_readonly(&path);
+                    if opened.is_ok() {
+                        os::prepared_publication_test_hooks::run(
+                            os::prepared_publication_test_hooks::Stage::MetadataReadAfterOpen,
+                            &path,
+                        );
+                    }
+                    let result = read_fn(opened);
+                    os::prepared_publication_test_hooks::run(
+                        os::prepared_publication_test_hooks::Stage::MetadataReadAfterRead,
+                        &path,
+                    );
+                    Ok(result)
+                }
+                #[cfg(not(all(any(test, feature = "test-util"), not(windows))))]
                 Ok(read_fn(root.open_readonly(&path)))
             })
             .await

crates/ecstore/src/disk/os.rs

@@ -333,6 +333,8 @@ pub(crate) mod prepared_publication_test_hooks {
         PreparedRename,
         Rename,
         Remove,
+        MetadataReadAfterOpen,
+        MetadataReadAfterRead,
         #[cfg(test)]
         Rollback,
         #[cfg(test)]
@@ -457,6 +459,8 @@ pub enum LocalPublicationStage {
     PreparedRename,
     Rename,
     Remove,
+    MetadataReadAfterOpen,
+    MetadataReadAfterRead,
 }
 
 #[cfg(all(feature = "test-util", not(windows)))]
@@ -469,6 +473,8 @@ impl LocalPublicationPause {
             LocalPublicationStage::PreparedRename => prepared_publication_test_hooks::Stage::PreparedRename,
             LocalPublicationStage::Rename => prepared_publication_test_hooks::Stage::Rename,
             LocalPublicationStage::Remove => prepared_publication_test_hooks::Stage::Remove,
+            LocalPublicationStage::MetadataReadAfterOpen => prepared_publication_test_hooks::Stage::MetadataReadAfterOpen,
+            LocalPublicationStage::MetadataReadAfterRead => prepared_publication_test_hooks::Stage::MetadataReadAfterRead,
         };
         let (entered_tx, entered) = oneshot::channel();
         let (release, release_rx) = std::sync::mpsc::channel::<()>();

crates/ecstore/src/set_disk/mod.rs

@@ -4245,14 +4245,23 @@ pub(super) struct MultipartWriteQuorumContext<'a> {
     part_number: Option<usize>,
 }
 
+fn record_multipart_write_quorum_failure(
+    stage: &'static str,
+    errs: &[Option<DiskError>],
+    write_quorum: usize,
+) -> crate::disk::error_reduce::WriteQuorumFailureSummary {
+    let summary = build_write_quorum_failure_summary(errs, OBJECT_OP_IGNORED_ERRS, write_quorum);
+    runtime_sources::record_erasure_write_quorum_failure(stage, summary.dominant_error_label);
+    summary
+}
+
 fn log_multipart_write_quorum_failure(
     context: MultipartWriteQuorumContext<'_>,
     errs: &[Option<DiskError>],
     write_quorum: usize,
     returned_error: &DiskError,
 ) {
-    let summary = build_write_quorum_failure_summary(errs, OBJECT_OP_IGNORED_ERRS, write_quorum);
-    runtime_sources::record_erasure_write_quorum_failure(context.stage, summary.dominant_error_label);
+    let summary = record_multipart_write_quorum_failure(context.stage, errs, write_quorum);
     warn!(
         target: "rustfs_ecstore::set_disk",
         event = EVENT_SET_DISK_MULTIPART,

crates/ecstore/src/set_disk/ops/delete_recovery.rs

@@ -40,9 +40,35 @@ pub(crate) mod test_hooks {
     use std::sync::{Arc, Mutex};
 
     type Hook = Arc<dyn Fn() -> BoxFuture<'static, ()> + Send + Sync>;
+    type TransactionLockHook = Arc<dyn Fn(&rustfs_lock::NamespaceLockGuard) + Send + Sync>;
 
     static BEFORE_GC_FINALIZE: Mutex<Vec<(String, String, Hook)>> = Mutex::new(Vec::new());
     static CLEANUP_ATTEMPTS: Mutex<Vec<(String, String)>> = Mutex::new(Vec::new());
+    static AFTER_TRANSACTION_LOCK: Mutex<Vec<(String, String, TransactionLockHook)>> = Mutex::new(Vec::new());
+
+    pub(crate) fn after_transaction_lock_acquired(bucket: &str, object: &str, hook: TransactionLockHook) {
+        AFTER_TRANSACTION_LOCK
+            .lock()
+            .expect("transaction lock hooks")
+            .push((bucket.to_owned(), object.to_owned(), hook));
+    }
+
+    pub(in crate::set_disk) fn run_after_transaction_lock_acquired(
+        bucket: &str,
+        object: &str,
+        guard: &rustfs_lock::NamespaceLockGuard,
+    ) {
+        let hook = {
+            let mut hooks = AFTER_TRANSACTION_LOCK.lock().expect("transaction lock hooks");
+            hooks
+                .iter()
+                .position(|(hook_bucket, hook_object, _)| hook_bucket == bucket && hook_object == object)
+                .map(|index| hooks.remove(index).2)
+        };
+        if let Some(hook) = hook {
+            hook(guard);
+        }
+    }
 
     pub(super) fn record_cleanup_attempt(bucket: &str, object: &str) {
         CLEANUP_ATTEMPTS
@@ -112,6 +138,7 @@ pub(crate) struct DeleteRecoveryContext<'a> {
     /// Only the locked heal path may repair a live marker-creation source.
     pub repair_marker_source: bool,
     pub namespace_owner: Option<Arc<dyn Send + Sync>>,
+    pub transaction_guard: Option<Arc<rustfs_lock::NamespaceLockGuard>>,
     pub recovery_ticket: Option<crate::store::delete_recovery_runtime::DeleteRecoveryTicket>,
     pub published_hint: Option<(Uuid, &'a [Result<DeleteRecoveryInspection>])>,
     pub can_commit: &'a (dyn Fn() -> bool + Sync),
@@ -125,6 +152,7 @@ impl<'a> DeleteRecoveryContext<'a> {
             explicit_delete: false,
             repair_marker_source: false,
             namespace_owner: None,
+            transaction_guard: None,
             recovery_ticket: None,
             published_hint: None,
             can_commit,
@@ -373,9 +401,22 @@ impl SetDisks {
         write_quorum: usize,
         mut context: DeleteRecoveryContext<'_>,
     ) -> Result<()> {
-        if context.namespace_owner.is_none() {
-            context.namespace_owner = Some(self.ctx.begin_namespace_commit());
-        }
+        let transaction_guard = match context.transaction_guard.take() {
+            Some(guard) => guard,
+            None => self
+                .acquire_delete_transaction_lock(bucket, object)
+                .await
+                .map_err(DiskError::other)?,
+        };
+        let outer_can_commit = context.can_commit;
+        let can_commit = || outer_can_commit() && !transaction_guard.is_lock_lost();
+        context.can_commit = &can_commit;
+        context.transaction_guard = Some(Arc::clone(&transaction_guard));
+        let owner = context
+            .namespace_owner
+            .take()
+            .unwrap_or_else(|| self.ctx.begin_namespace_commit());
+        context.namespace_owner = Some(Arc::new((owner, Arc::clone(&transaction_guard))));
         let can_commit = context.can_commit;
         let states = inspect(disks, bucket, object, transaction).await;
         let untouched_absence = |state: &Result<DeleteRecoveryInspection>| matches!(state, Ok(state) if state.state == DeleteRecoveryState::Absent && state.current_digest.is_none());
@@ -547,8 +588,25 @@ impl SetDisks {
         &self,
         bucket: &str,
         object: &str,
-        context: DeleteRecoveryContext<'_>,
+        mut context: DeleteRecoveryContext<'_>,
     ) -> Result<DeleteRecoverySummary> {
+        let transaction_guard = match context.transaction_guard.take() {
+            Some(guard) => guard,
+            None => self
+                .acquire_delete_transaction_lock(bucket, object)
+                .await
+                .map_err(DiskError::other)?,
+        };
+        let outer_can_commit = context.can_commit;
+        let can_commit = || outer_can_commit() && !transaction_guard.is_lock_lost();
+        context.can_commit = &can_commit;
+        if !context.dry_run {
+            let owner = context
+                .namespace_owner
+                .take()
+                .unwrap_or_else(|| self.ctx.begin_namespace_commit());
+            context.namespace_owner = Some(Arc::new((owner, Arc::clone(&transaction_guard))));
+        }
         let DeleteRecoveryContext {
             incarnation,
             dry_run,
@@ -558,6 +616,7 @@ impl SetDisks {
             published_hint,
             can_commit,
             recovery_ticket: _,
+            transaction_guard: _,
         } = context;
         let disks = self.disk_inventory().await;
         let complete_inventory = disks.len() == self.set_drive_count && disks.iter().all(Option::is_some);
@@ -1257,6 +1316,135 @@ mod tests {
         assert_eq!(body(&store, bucket, None).await, original);
     }
 
+    #[tokio::test]
+    async fn delete_recovery_deferred_batch_discards_released_alias_fence_and_preserves_caller_fence() {
+        use crate::bucket::metadata_sys::ObjectLockConfigState;
+        use crate::object_api::{NamespaceLockFence, NamespaceLockSignalTestFence, ObjectLockConfigSnapshot};
+        use crate::storage_api_contracts::object::ObjectToDelete;
+        use std::sync::Mutex;
+        use std::sync::atomic::{AtomicBool, Ordering};
+
+        for lose_caller in [false, true] {
+            let bucket = if lose_caller {
+                "deferred-batch-lost-caller"
+            } else {
+                "deferred-batch-released-alias"
+            };
+            let (_dirs, store, disks) = fixture(bucket).await;
+            put(&store, bucket, &[27; 4096], false).await;
+            let transaction = applied(&store, &disks, bucket, None, disks.len()).await;
+            let before = join_all(
+                disks
+                    .iter()
+                    .map(|disk| disk.inspect_delete_transaction(bucket, "object", transaction)),
+            )
+            .await
+            .into_iter()
+            .collect::<Result<Vec<_>>>()
+            .expect("capture pending recovery evidence");
+            let mut set = (*store.pools[0].disk_set[0]).clone();
+            set.lockers = vec![Arc::new(rustfs_lock::LocalClient::with_manager(Arc::new(
+                rustfs_lock::GlobalLockManager::Enabled(Arc::new(rustfs_lock::FastObjectLockManager::new())),
+            )))];
+            set.ctx
+                .update_erasure_type(crate::layout::endpoints::SetupType::DistErasure)
+                .await;
+
+            let (caller_fence, caller_lost) = NamespaceLockFence::loss_handle_for_test();
+            let released_alias_lost = Arc::new(AtomicBool::new(false));
+            let signal_fence = Arc::new(Mutex::new(None));
+            let captured_signal_fence = Arc::clone(&signal_fence);
+            let captured_alias_lost = Arc::clone(&released_alias_lost);
+            test_hooks::after_transaction_lock_acquired(
+                bucket,
+                "object",
+                Arc::new(move |guard| {
+                    let signal = guard.lock_lost_signal().expect("distributed alias signal");
+                    let fence = NamespaceLockSignalTestFence::install_with_loss_handle(&signal, Arc::clone(&captured_alias_lost));
+                    // Retain the signal so a later allocation cannot reuse its
+                    // registry identity after the original guard is dropped.
+                    *captured_signal_fence.lock().expect("captured alias fence") = Some((fence, signal));
+                }),
+            );
+            let replay_started = Arc::new(AtomicBool::new(false));
+            let captured_replay_started = Arc::clone(&replay_started);
+            let expired_alias = Arc::clone(&released_alias_lost);
+            test_hooks::after_transaction_lock_acquired(
+                bucket,
+                "object",
+                Arc::new(move |_| {
+                    // Acquiring the same transaction key again proves the first
+                    // lease was released. Only its copied fence becomes stale.
+                    expired_alias.store(true, Ordering::Release);
+                    caller_lost.store(lose_caller, Ordering::Release);
+                    captured_replay_started.store(true, Ordering::Release);
+                }),
+            );
+
+            let (deleted, errors) = set
+                .delete_objects(
+                    bucket,
+                    vec![ObjectToDelete {
+                        object_name: "object".into(),
+                        ..Default::default()
+                    }],
+                    ObjectOptions {
+                        namespace_lock_fence: Some(caller_fence),
+                        object_lock_config_snapshot: Some(Arc::new(ObjectLockConfigSnapshot::new(
+                            ObjectLockConfigState::ConfirmedAbsent,
+                        ))),
+                        ..Default::default()
+                    },
+                )
+                .await;
+            assert!(
+                replay_started.load(Ordering::Acquire),
+                "missing metadata must take the deferred replay path"
+            );
+            assert!(
+                released_alias_lost.load(Ordering::Acquire),
+                "the completed batch alias must be marked lost"
+            );
+            if lose_caller {
+                assert!(errors[0].is_some(), "losing the original caller fence must reject deferred replay");
+                for (disk, original) in disks.iter().zip(before) {
+                    let after = disk
+                        .inspect_delete_transaction(bucket, "object", transaction)
+                        .await
+                        .expect("retained proof");
+                    assert_eq!(
+                        after.fingerprint, original.fingerprint,
+                        "lost caller authority must preserve every prepared journal"
+                    );
+                }
+            } else {
+                assert!(
+                    errors.iter().all(Option::is_none),
+                    "released alias loss must not reject fresh recovery: {errors:?}"
+                );
+                assert!(
+                    !deleted[0].found,
+                    "fresh unversioned recovery commits absence before the idempotent batch retry"
+                );
+                for disk in &disks {
+                    assert!(
+                        discover(disk, bucket, Some("object"))
+                            .await
+                            .expect("final recovery evidence")
+                            .is_empty()
+                    );
+                    assert_eq!(
+                        disk.read_version("", bucket, "object", "", &ReadOptions::default())
+                            .await
+                            .expect_err("replayed delete must remove the source"),
+                        DiskError::FileNotFound
+                    );
+                }
+            }
+            drop(signal_fence);
+        }
+    }
+
     #[tokio::test]
     async fn delete_recovery_corrupt_bucket_does_not_prevent_other_bucket_rollback() {
         let bad_bucket = "recover-corrupt-bucket";

crates/ecstore/src/set_disk/ops/heal.rs

@@ -3634,6 +3634,18 @@ impl SetDisks {
             return Ok((result, err.map(|e| e.into())));
         }
 
+        // Keep the transaction key through both replay and the metadata heal
+        // based on that replay. The raw target key always precedes this key.
+        let transaction_guard =
+            if _write_lock_guard.is_some() && !opts.read_repair && !crate::bucket::utils::is_meta_bucketname(bucket) {
+                Some(self.acquire_delete_transaction_lock(bucket, object).await?)
+            } else {
+                None
+            };
+        let locks_lost = || {
+            _write_lock_guard.as_deref().is_some_and(|guard| guard.is_lock_lost())
+                || transaction_guard.as_ref().is_some_and(|guard| guard.is_lock_lost())
+        };
         let mut recovery_removed_version = false;
         if !opts.read_repair
             && _write_lock_guard.is_some()
@@ -3655,12 +3667,17 @@ impl SetDisks {
                         dry_run: opts.dry_run,
                         explicit_delete,
                         repair_marker_source: true,
+                        transaction_guard: transaction_guard.clone(),
                         namespace_owner: (!opts.dry_run).then(|| {
-                            Arc::new((scope.clone(), self.ctx.begin_namespace_commit(), _write_lock_guard.clone()))
-                                as Arc<dyn Send + Sync>
+                            Arc::new((
+                                scope.clone(),
+                                self.ctx.begin_namespace_commit(),
+                                _write_lock_guard.clone(),
+                                transaction_guard.clone(),
+                            )) as Arc<dyn Send + Sync>
                         }),
                         ..crate::set_disk::DeleteRecoveryContext::new(Some(scope.incarnation), &|| {
-                            scope.check().is_ok() && !_write_lock_guard.as_deref().is_some_and(|guard| guard.is_lock_lost())
+                            scope.check().is_ok() && !locks_lost()
                         })
                     },
                 )
@@ -3752,7 +3769,7 @@ impl SetDisks {
                 && errs
                     .iter()
                     .all(|err| matches!(err, Some(DiskError::FileNotFound | DiskError::FileVersionNotFound)))
-                && !_write_lock_guard.as_deref().is_some_and(|guard| guard.is_lock_lost())
+                && !locks_lost()
             {
                 *absence = Some(HealedObjectAbsence {
                     pool_index: self.pool_index,
@@ -3767,8 +3784,10 @@ impl SetDisks {
         // Pass no_lock=true since we already obtained write lock (or are already called with no_lock=true)
         let mut inner_opts = *opts;
         inner_opts.no_lock = true;
-        let commit_fence = || !_write_lock_guard.as_ref().is_some_and(|guard| guard.is_lock_lost());
-        let namespace_owner = _write_lock_guard.as_ref().map(|guard| guard.clone() as Arc<dyn Send + Sync>);
+        let commit_fence = || !locks_lost();
+        let namespace_owner = _write_lock_guard
+            .as_ref()
+            .map(|guard| Arc::new((Arc::clone(guard), transaction_guard.clone())) as Arc<dyn Send + Sync>);
         let (result, err) = pin_object_heal_future(|| {
             self.heal_object_with_explicit_version_regen(
                 bucket,
@@ -3815,7 +3834,7 @@ impl SetDisks {
                         result,
                         err.map(Into::into),
                         absence,
-                        _write_lock_guard.as_deref().is_some_and(|guard| guard.is_lock_lost()),
+                        locks_lost(),
                         bucket,
                         object,
                     ));
@@ -3827,7 +3846,7 @@ impl SetDisks {
             result,
             err.map(Into::into),
             absence,
-            _write_lock_guard.as_deref().is_some_and(|guard| guard.is_lock_lost()),
+            locks_lost(),
             bucket,
             object,
         ))

crates/ecstore/src/set_disk/ops/locking.rs

@@ -44,6 +44,21 @@ impl crate::storage_api_contracts::namespace::NamespaceLocking for SetDisks {
 
     #[tracing::instrument(level = "trace", skip(self))]
     async fn new_ns_lock(&self, bucket: &str, object: &str) -> Result<NamespaceLockWrapper> {
+        // Lock the file the disk resolves, not the spelling: on Windows `a\b`
+        // and `a/b` share one xl.meta, so they must share one lock. The key is
+        // folded by the requesting node only; lock servers compare it verbatim.
+        let resource = ObjectKey {
+            bucket: Arc::from(bucket),
+            object: Arc::from(object_name_disk_identity(object).as_ref()),
+            version: None,
+        };
+
+        Ok(self.namespace_lock_for_key(resource).await)
+    }
+}
+
+impl SetDisks {
+    async fn namespace_lock_for_key(&self, resource: ObjectKey) -> NamespaceLockWrapper {
         // Resolved from this set's own instance context (backlog#1052), not the
         // ambient facade: the facade tracks whichever context is currently
         // published process-wide, so a second instance (or, in tests, another
@@ -69,20 +84,33 @@ impl crate::storage_api_contracts::namespace::NamespaceLocking for SetDisks {
             NamespaceLock::with_local_manager_shared(self.set_lock_namespace.clone(), self.local_lock_manager.clone())
         };
 
-        // Lock the file the disk resolves, not the spelling: on Windows `a\b`
-        // and `a/b` share one xl.meta, so they must share one lock. The key is
-        // folded by the requesting node only; lock servers compare it verbatim.
-        let resource = ObjectKey {
-            bucket: Arc::from(bucket),
-            object: Arc::from(object_name_disk_identity(object).as_ref()),
-            version: None,
-        };
-
-        Ok(NamespaceLockWrapper::new(set_lock, resource, self.locker_owner.clone()))
+        NamespaceLockWrapper::new(set_lock, resource, self.locker_owner.clone())
+    }
+
+    /// Raw object locks precede this set-local transaction lock. Its versioned
+    /// resource cannot collide with normal namespace keys, which use None.
+    /// Keeping the target set's clients avoids nesting overlapping raw quorums.
+    pub(in crate::set_disk) async fn acquire_delete_transaction_lock(
+        &self,
+        bucket: &str,
+        object: &str,
+    ) -> Result<Arc<rustfs_lock::NamespaceLockGuard>> {
+        let resource = ObjectKey::with_version(
+            bucket,
+            object_name_disk_identity(object).as_ref(),
+            format!("rustfs:delete-transaction:{}:{}", self.pool_index, self.set_index),
+        );
+        let guard = self
+            .namespace_lock_for_key(resource)
+            .await
+            .get_write_lock(super::super::get_lock_acquire_timeout())
+            .await
+            .map_err(|error| self.map_namespace_lock_error(bucket, object, "delete_transaction", error))?;
+        #[cfg(test)]
+        super::delete_recovery::test_hooks::run_after_transaction_lock_acquired(bucket, object, &guard);
+        Ok(Arc::new(guard))
     }
-}
 
-impl SetDisks {
     #[allow(dead_code, reason = "lock diagnostics formatter with no caller in this port (backlog#1823)")]
     pub(in crate::set_disk) fn format_lock_error(&self, bucket: &str, object: &str, mode: &str, err: &LockResult) -> String {
         match err {

crates/ecstore/src/set_disk/ops/multipart.rs

@@ -44,9 +44,9 @@ use super::super::{
     create_bitrot_writer, debug, disk, error, file_info_is_valid_for_metadata, get_complete_multipart_md5, get_header_map,
     get_str, insert_str, is_err_object_not_found, is_err_version_not_found, is_min_allowed_part_size,
     log_multipart_write_quorum_failure, parts_after_marker, path_join_buf, prepare_complete_multipart_parts,
-    record_compression_total_memory, reduce_read_quorum_errs, reduce_write_quorum_errs, remove_header_map, resolve_write_layout,
-    restore_commit_operation_id_from_metadata, should_persist_encryption_original_size, strip_internal_multipart_metadata,
-    to_object_err, warn,
+    record_compression_total_memory, record_multipart_write_quorum_failure, reduce_read_quorum_errs, reduce_write_quorum_errs,
+    remove_header_map, resolve_write_layout, restore_commit_operation_id_from_metadata, should_persist_encryption_original_size,
+    strip_internal_multipart_metadata, to_object_err, warn,
 };
 use super::bitrot_self_verify::{BitrotSelfVerifyTarget, drop_failed_writer_disks, verify_written_bitrot_shards};
 #[cfg(test)]
@@ -233,6 +233,19 @@ fn admitted_multipart_size(current: u64, candidate: u64, limit: u64) -> Result<u
     Ok(total)
 }
 
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum MultipartMetadataQuorum {
+    Read,
+    Write,
+    Cleanup,
+}
+
+impl From<bool> for MultipartMetadataQuorum {
+    fn from(write: bool) -> Self {
+        if write { Self::Write } else { Self::Read }
+    }
+}
+
 pub(crate) struct StaleMultipartCleanupGuard {
     file_info: FileInfo,
     upload_path: String,
@@ -1139,7 +1152,7 @@ impl SetDisks {
             }
             let upload_id = runtime_sources::deployment_upload_id(raw_upload_id);
             let file_info = match self
-                .check_multipart_upload_path_exists(bucket, object, &upload_id, &upload_path, false, true)
+                .check_multipart_upload_path_exists(bucket, object, &upload_id, &upload_path, MultipartMetadataQuorum::Read, true)
                 .await
             {
                 Ok((file_info, _)) => file_info,
@@ -1226,7 +1239,7 @@ impl SetDisks {
             .acquire_write_lock_diag("abort_data_movement_multipart", RUSTFS_META_MULTIPART_BUCKET, &upload_path)
             .await?;
         let file_info = match self
-            .check_multipart_upload_path_exists(bucket, object, upload_id, &upload_path, true, true)
+            .check_multipart_upload_path_exists(bucket, object, upload_id, &upload_path, MultipartMetadataQuorum::Write, true)
             .await
         {
             Ok((file_info, _)) => file_info,
@@ -1333,7 +1346,7 @@ impl SetDisks {
         data_movement: bool,
     ) -> Result<(FileInfo, Vec<FileInfo>)> {
         let upload_id_path = Self::validated_multipart_upload_path(bucket, object, upload_id, data_movement)?;
-        self.check_multipart_upload_path_exists(bucket, object, upload_id, &upload_id_path, write, false)
+        self.check_multipart_upload_path_exists(bucket, object, upload_id, &upload_id_path, write.into(), false)
             .await
     }
 
@@ -1373,7 +1386,7 @@ impl SetDisks {
         object: &str,
         upload_id: &str,
         upload_id_path: &str,
-        write: bool,
+        quorum_mode: MultipartMetadataQuorum,
         include_recovery: bool,
     ) -> Result<(FileInfo, Vec<FileInfo>)> {
         // Slow metadata I/O must not hold the topology registry's read lock.
@@ -1489,22 +1502,26 @@ impl SetDisks {
         }
 
         let mut quorum = read_quorum as usize;
-        if write {
+        if quorum_mode != MultipartMetadataQuorum::Read {
             quorum = write_quorum as usize;
 
             if let Some(err) = reduce_write_quorum_errs(&errs, OBJECT_OP_IGNORED_ERRS, quorum) {
-                log_multipart_write_quorum_failure(
-                    MultipartWriteQuorumContext {
-                        stage: MULTIPART_WRITE_QUORUM_UPLOAD_METADATA,
-                        bucket,
-                        object,
-                        upload_id,
-                        part_number: None,
-                    },
-                    &errs,
-                    quorum,
-                    &err,
-                );
+                if quorum_mode == MultipartMetadataQuorum::Write {
+                    log_multipart_write_quorum_failure(
+                        MultipartWriteQuorumContext {
+                            stage: MULTIPART_WRITE_QUORUM_UPLOAD_METADATA,
+                            bucket,
+                            object,
+                            upload_id,
+                            part_number: None,
+                        },
+                        &errs,
+                        quorum,
+                        &err,
+                    );
+                } else {
+                    record_multipart_write_quorum_failure(MULTIPART_WRITE_QUORUM_UPLOAD_METADATA, &errs, quorum);
+                }
                 return Err(map_error(err));
             }
         } else if let Some(err) = reduce_read_quorum_errs(&errs, OBJECT_OP_IGNORED_ERRS, quorum) {
@@ -1523,7 +1540,7 @@ impl SetDisks {
             .acquire_write_lock_diag("stale_multipart_cleanup", RUSTFS_META_MULTIPART_BUCKET, upload_path)
             .await?;
         let (file_info, _) = self
-            .check_multipart_upload_path_exists("", "", "", upload_path, true, true)
+            .check_multipart_upload_path_exists("", "", "", upload_path, MultipartMetadataQuorum::Cleanup, true)
             .await?;
         let write_quorum = file_info.write_quorum(self.default_write_quorum());
         Ok(StaleMultipartCleanupGuard {
@@ -3032,7 +3049,7 @@ impl crate::storage_api_contracts::multipart::MultipartOperations for SetDisks {
         // its full write quorum and the upload's incarnation/lifecycle fences.
         let upload_id_path = Self::validated_multipart_upload_path(bucket, object, upload_id, opts.data_movement)?;
         let (fi, _) = self
-            .check_multipart_upload_path_exists(bucket, object, upload_id, &upload_id_path, false, true)
+            .check_multipart_upload_path_exists(bucket, object, upload_id, &upload_id_path, MultipartMetadataQuorum::Read, true)
             .await?;
         ensure_data_movement_upload_access(&fi, bucket, object, upload_id, opts)?;
         ensure_multipart_bucket_incarnation(&self.ctx, &fi, bucket, object, upload_id, opts.expected_bucket_incarnation_id)
@@ -3192,7 +3209,14 @@ impl crate::storage_api_contracts::multipart::MultipartOperations for SetDisks {
                     }
                     SourceRecovery::Missing => {
                         return match self
-                            .check_multipart_upload_path_exists(bucket, object, upload_id, &upload_id_path, false, true)
+                            .check_multipart_upload_path_exists(
+                                bucket,
+                                object,
+                                upload_id,
+                                &upload_id_path,
+                                MultipartMetadataQuorum::Read,
+                                true,
+                            )
                             .await
                         {
                             Ok(_) => Err(Error::ErasureWriteQuorum),
@@ -11133,7 +11157,7 @@ mod tests {
             *disk = None;
         }
         let (info, _) = set
-            .check_multipart_upload_path_exists(bucket, object, &upload, &path, false, true)
+            .check_multipart_upload_path_exists(bucket, object, &upload, &path, MultipartMetadataQuorum::Read, true)
             .await
             .expect("four primary plus four recovery copies reach metadata read quorum");
         assert_eq!(info.name, path);
@@ -11154,7 +11178,7 @@ mod tests {
             *disk = None;
         }
         assert!(
-            set.check_multipart_upload_path_exists(bucket, object, &upload, &path, false, true)
+            set.check_multipart_upload_path_exists(bucket, object, &upload, &path, MultipartMetadataQuorum::Read, true)
                 .await
                 .is_err(),
             "two files on each of four disks must not count as eight voters"
@@ -14471,7 +14495,7 @@ mod tests {
                     object,
                     &u_new,
                     &SetDisks::get_upload_id_dir(bucket, object, &u_new),
-                    true,
+                    MultipartMetadataQuorum::Write,
                     true,
                 )
                 .await
@@ -14516,7 +14540,7 @@ mod tests {
                 object,
                 &upload,
                 &SetDisks::get_upload_id_dir(bucket, object, &upload),
-                true,
+                MultipartMetadataQuorum::Write,
                 true,
             )
             .await
@@ -14599,7 +14623,7 @@ mod tests {
                     assert_completion_files_preserved(&disk_stores, RUSTFS_META_MULTIPART_BUCKET, &source_files).await;
                     set_disks
                         .check_multipart_upload_path_exists(
-                            bucket, object, &u_new, &SetDisks::get_upload_id_dir(bucket, object, &u_new), true, true,
+                            bucket, object, &u_new, &SetDisks::get_upload_id_dir(bucket, object, &u_new), MultipartMetadataQuorum::Write, true,
                         )
                         .await
                         .expect("upload authority must survive the post-commit crash");

crates/ecstore/src/set_disk/ops/multipart_abort_tests.rs

@@ -507,7 +507,7 @@ mod native_abort_closure_tests {
         let path = SetDisks::get_upload_id_dir(bucket, object, &upload);
         pin_historical_unmarked_upload(&disks, bucket, &path).await;
         let before = originals(&disks, &path).await;
-        set.check_multipart_upload_path_exists(bucket, object, &upload, &path, false, true)
+        set.check_multipart_upload_path_exists(bucket, object, &upload, &path, MultipartMetadataQuorum::Read, true)
             .await
             .expect("readonly legacy cleanup identity lookup");
         assert_eq!(
@@ -786,7 +786,7 @@ mod native_abort_closure_tests {
             "known orphan native evidence remains unknown: {inspected:?}"
         );
         let readonly = set
-            .check_multipart_upload_path_exists(bucket, object, &upload, &path, false, true)
+            .check_multipart_upload_path_exists(bucket, object, &upload, &path, MultipartMetadataQuorum::Read, true)
             .await;
         assert!(
             matches!(

crates/ecstore/src/set_disk/ops/object.rs

@@ -73,6 +73,7 @@ struct DeleteCommitContext<'a> {
     incarnation: Option<Uuid>,
     options: Option<&'a ObjectOptions>,
     guard: Option<Arc<super::super::ObjectLockDiagGuard>>,
+    transaction_guard: Option<Arc<rustfs_lock::NamespaceLockGuard>>,
 }
 
 impl<'a> DeleteCommitContext<'a> {
@@ -81,17 +82,37 @@ impl<'a> DeleteCommitContext<'a> {
             incarnation: options.expected_bucket_incarnation_id,
             options: Some(options),
             guard: guard.cloned(),
+            transaction_guard: None,
         }
     }
 
+    fn with_transaction_guard(mut self, guard: Option<&Arc<rustfs_lock::NamespaceLockGuard>>) -> Self {
+        self.transaction_guard = guard.cloned();
+        self
+    }
+
+    fn ensure_transaction_lock_held(&self, bucket: &str, object: &str) -> Result<()> {
+        if self.transaction_guard.as_ref().is_some_and(|guard| guard.is_lock_lost()) {
+            return Err(StorageError::NamespaceLockQuorumUnavailable {
+                mode: "delete_transaction",
+                bucket: bucket.to_owned(),
+                object: object.to_owned(),
+                required: 1,
+                achieved: 0,
+            });
+        }
+        Ok(())
+    }
+
     fn can_commit(&self, bucket: &str, object: &str) -> bool {
-        self.options.is_none_or(|options| {
-            ensure_delete_commit_locks_held(self.guard.as_deref(), bucket, object, options).is_ok()
-                && options
-                    .scanner_publication_commit_scope
-                    .as_ref()
-                    .is_none_or(|scope| scope.can_commit())
-        })
+        !self.transaction_guard.as_ref().is_some_and(|guard| guard.is_lock_lost())
+            && self.options.is_none_or(|options| {
+                ensure_delete_commit_locks_held(self.guard.as_deref(), bucket, object, options).is_ok()
+                    && options
+                        .scanner_publication_commit_scope
+                        .as_ref()
+                        .is_none_or(|scope| scope.can_commit())
+            })
     }
 }
 
@@ -3852,6 +3873,7 @@ impl SetDisks {
         object: &str,
         opts: &ObjectOptions,
         lock_guard: Option<&Arc<super::super::ObjectLockDiagGuard>>,
+        transaction_guard: Option<&Arc<rustfs_lock::NamespaceLockGuard>>,
     ) -> Result<bool> {
         if is_meta_bucketname(bucket)
             || opts.version_id.is_some()
@@ -3888,6 +3910,7 @@ impl SetDisks {
                 object,
                 DeleteRecoveryContext {
                     explicit_delete: true,
+                    transaction_guard: transaction_guard.cloned(),
                     namespace_owner: Some(Arc::new((
                         self.ctx.begin_namespace_commit(),
                         lock_guard.cloned(),
@@ -8839,7 +8862,7 @@ impl SetDisks {
         // quorum, failing write quorum on update_object_meta (backlog#872).
         let read_opts = opts.as_read_opts();
         let (mut fi, _, disks) = self
-            .get_object_fileinfo_gated(bucket, object, &read_opts, false, false)
+            .get_object_fileinfo_for_metadata_update(bucket, object, &read_opts)
             .await?
             .into_owned();
 
@@ -8877,8 +8900,11 @@ impl SetDisks {
         fi: &FileInfo,
         force_del_marker: bool,
         delete_marker_purge: Option<MrfDeleteMarkerPurge>,
-        commit_context: DeleteCommitContext<'_>,
+        mut commit_context: DeleteCommitContext<'_>,
     ) -> Result<()> {
+        if !is_meta_bucketname(bucket) && commit_context.transaction_guard.is_none() {
+            commit_context.transaction_guard = Some(self.acquire_delete_transaction_lock(bucket, object).await?);
+        }
         let source_bucket_incarnation_id = commit_context.incarnation;
         let transported = delete_file_info_with_replication_transport_metadata(fi);
         let fi = &transported;
@@ -8887,6 +8913,7 @@ impl SetDisks {
             Arc::new((
                 self.ctx.begin_namespace_commit(),
                 commit_context.guard.clone(),
+                commit_context.transaction_guard.clone(),
                 commit_context
                     .options
                     .and_then(|options| options.object_lock_config_snapshot.clone()),
@@ -8926,7 +8953,11 @@ impl SetDisks {
 
         for disk in disks.iter() {
             let disk_namespace_owner = namespace_owner.clone().map(|owner| owner as Arc<dyn Send + Sync>);
+            let transaction_guard = commit_context.transaction_guard.as_ref();
             futures.push(async move {
+                if transaction_guard.is_some_and(|guard| guard.is_lock_lost()) {
+                    return Err(DiskError::DiskOngoingReq);
+                }
                 if let Some(disk) = disk {
                     let options = DeleteOptions {
                         old_data_dir: Some(rollback_dir),
@@ -8976,6 +9007,7 @@ impl SetDisks {
             }
         }
 
+        commit_context.ensure_transaction_lock_held(bucket, object)?;
         let mut quorum_result = resolve_tiered_decommission_write_quorum_result(&errs, write_quorum, bucket, object);
         if !is_meta_bucketname(bucket) && errs.iter().flatten().any(super::delete_recovery::unsupported_recovery) {
             quorum_result = Err(DiskError::UnsupportedDisk.into());
@@ -9008,6 +9040,7 @@ impl SetDisks {
                 write_quorum,
                 DeleteRecoveryContext {
                     recovery_ticket,
+                    transaction_guard: commit_context.transaction_guard.clone(),
                     namespace_owner: namespace_owner.clone().map(|owner| owner as Arc<dyn Send + Sync>),
                     ..DeleteRecoveryContext::new(source_bucket_incarnation_id, &|| commit_context.can_commit(bucket, object))
                 },
@@ -9017,6 +9050,7 @@ impl SetDisks {
         }
         #[cfg(test)]
         pause_delete_before_cleanup(bucket).await;
+        commit_context.ensure_transaction_lock_held(bucket, object)?;
         let mut rollback_futures = Vec::new();
         for (index, err) in errs.iter().enumerate() {
             if structured_cleanup {
@@ -9042,7 +9076,11 @@ impl SetDisks {
             let object = object.to_string();
             let fi = fi.clone();
             let disk_namespace_owner = namespace_owner.clone().map(|owner| owner as Arc<dyn Send + Sync>);
+            let transaction_guard = commit_context.transaction_guard.as_ref();
             rollback_futures.push(async move {
+                if transaction_guard.is_some_and(|guard| guard.is_lock_lost()) {
+                    return;
+                }
                 if should_rollback {
                     // The dedicated undo path never forwards the marker-only creation flag.
                     if let Err(err) = disk
@@ -9099,6 +9137,7 @@ impl SetDisks {
         }
 
         join_all(rollback_futures).await;
+        commit_context.ensure_transaction_lock_held(bucket, object)?;
         drop(namespace_owner);
         if quorum_result.is_ok()
             && errs.iter().any(Option::is_some)
@@ -9294,36 +9333,56 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
             }
         };
 
-        let (read_quorum, write_quorum) = match Self::object_quorum_from_meta(&metas, &errs, self.default_parity_count) {
-            Ok((r, w)) => (
-                usize::try_from(r)
-                    .map_err(|_| to_object_err(DiskError::ErasureReadQuorum.into(), vec![src_bucket, src_object]))?,
-                usize::try_from(w)
-                    .map_err(|_| to_object_err(DiskError::ErasureWriteQuorum.into(), vec![src_bucket, src_object]))?,
-            ),
+        let src_version_id = src_opts.version_id.as_deref().unwrap_or_default();
+        let quorum = Self::object_quorum_from_meta(&metas, &errs, self.default_parity_count);
+        let selection = match &quorum {
+            Ok((read_quorum, write_quorum)) => {
+                let read_quorum = usize::try_from(*read_quorum)
+                    .map_err(|_| to_object_err(DiskError::ErasureReadQuorum.into(), vec![src_bucket, src_object]))?;
+                let write_quorum = usize::try_from(*write_quorum)
+                    .map_err(|_| to_object_err(DiskError::ErasureWriteQuorum.into(), vec![src_bucket, src_object]))?;
+                Self::select_fileinfo_for_read(src_bucket, &disks, &metas, &errs, src_version_id, read_quorum, write_quorum)
+                    .map(|(online_disks, fi)| (online_disks, fi, write_quorum))
+            }
+            Err(err) => Err(err.clone()),
+        };
+        let (online_disks, mut fi, write_quorum) = match selection {
+            Ok(selection) => selection,
             Err(mut err) => {
-                if err == DiskError::ErasureReadQuorum
-                    && !src_bucket.starts_with(RUSTFS_META_BUCKET)
-                    && self
-                        .delete_if_dangling(src_bucket, src_object, &metas, &errs, &HashMap::new(), src_opts.clone())
-                        .await
-                        .is_ok()
+                // The merged latest version can be one a failed PUT left below
+                // quorum; resolve it like a latest GET before the dangling
+                // cleanup below can report a key with a committed version absent.
+                if let Some(snapshot) = self
+                    .select_latest_past_dangling_versions(src_bucket, src_object, src_opts, true, &disks, &err)
+                    .await
                 {
-                    if src_opts.version_id.is_some() {
-                        err = DiskError::FileVersionNotFound
-                    } else {
-                        err = DiskError::FileNotFound
+                    // A version-only copy writes the served version's own
+                    // copies, so they and its write quorum replace the latest
+                    // read's.
+                    let (fi, parts_metadata, online_disks) = snapshot.into_owned();
+                    metas = parts_metadata;
+                    let write_quorum = fi.write_quorum(self.default_write_quorum());
+                    (online_disks, fi, write_quorum)
+                } else {
+                    if quorum.is_err()
+                        && err == DiskError::ErasureReadQuorum
+                        && !src_bucket.starts_with(RUSTFS_META_BUCKET)
+                        && self
+                            .delete_if_dangling(src_bucket, src_object, &metas, &errs, &HashMap::new(), src_opts.clone())
+                            .await
+                            .is_ok()
+                    {
+                        if src_opts.version_id.is_some() {
+                            err = DiskError::FileVersionNotFound
+                        } else {
+                            err = DiskError::FileNotFound
+                        }
                     }
+                    return Err(to_object_err(err.into(), vec![src_bucket, src_object]));
                 }
-                return Err(to_object_err(err.into(), vec![src_bucket, src_object]));
             }
         };
 
-        let src_version_id = src_opts.version_id.as_deref().unwrap_or_default();
-        let (online_disks, mut fi) =
-            Self::select_fileinfo_for_read(src_bucket, &disks, &metas, &errs, src_version_id, read_quorum, write_quorum)
-                .map_err(|e| to_object_err(e.into(), vec![src_bucket, src_object]))?;
-
         if fi.deleted {
             if src_opts.version_id.is_none() {
                 return Err(to_object_err(Error::FileNotFound, vec![src_bucket, src_object]));
@@ -9461,6 +9520,16 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                 }
             }
 
+            // A version-only copy writes and then reverts on a quorum miss;
+            // refuse it before writing when the served version's disks cannot
+            // reach its write quorum even if every write succeeds.
+            let reachable = online_disks
+                .iter()
+                .map(|disk| disk.is_none().then_some(DiskError::DiskNotFound))
+                .collect::<Vec<_>>();
+            if let Some(err) = reduce_write_quorum_errs(&reachable, OBJECT_OP_IGNORED_ERRS, write_quorum) {
+                return Err(to_object_err(err.into(), vec![src_bucket, src_object]));
+            }
             Self::write_unique_file_info(&online_disks, "", src_bucket, src_object, &metas, write_quorum)
                 .await
                 .map_err(|e| to_object_err(e.into(), vec![src_bucket, src_object]))?;
@@ -9528,9 +9597,8 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
         &self,
         bucket: &str,
         objects: Vec<ObjectToDelete>,
-        opts: ObjectOptions,
+        mut opts: ObjectOptions,
     ) -> (Vec<DeletedObject>, Vec<Option<Error>>, Vec<Option<DeleteAccounting>>) {
-        let current_generations = opts.conditional_delete_generations.as_deref();
         let mut del_objects = vec![DeletedObject::default(); objects.len()];
         let mut accounting = vec![None; objects.len()];
         let delete_config_snapshot = opts
@@ -9625,6 +9693,30 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
             }
         }
 
+        let outer_namespace_lock_fence = opts.namespace_lock_fence.clone();
+        let mut transaction_guards = std::collections::BTreeMap::new();
+        if !is_meta_bucketname(bucket) {
+            // Every raw batch lock is acquired first. Canonical sorting also
+            // gives aliases of one disk key exactly one transaction owner.
+            let keys: std::collections::BTreeSet<_> = locked_objects.iter().cloned().collect();
+            for key in keys {
+                match self.acquire_delete_transaction_lock(bucket, &key).await {
+                    Ok(guard) => {
+                        opts.add_namespace_lock_guard(&guard);
+                        transaction_guards.insert(key, guard);
+                    }
+                    Err(error) => {
+                        for (index, lock_name) in lock_names.iter().enumerate() {
+                            if lock_name.as_ref() == key {
+                                del_errs[index] = Some(error.clone());
+                            }
+                        }
+                    }
+                }
+            }
+        }
+        let transaction_guards = Arc::new(transaction_guards);
+        let current_generations = opts.conditional_delete_generations.as_deref();
         let object_lock_config = if is_meta_bucketname(bucket) {
             Arc::new(ObjectLockConfigSnapshot::new(ObjectLockConfigState::ConfirmedAbsent))
         } else {
@@ -9722,6 +9814,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                         &dobj.object_name,
                         DeleteRecoveryContext {
                             dry_run: !opts.no_lock,
+                            transaction_guard: transaction_guards.get(lock_names[i].as_ref()).cloned(),
                             namespace_owner: opts.delete_mutation_owner.clone(),
                             ..DeleteRecoveryContext::new(opts.expected_bucket_incarnation_id, &|| {
                                 ensure_delete_commit_locks_held(None, bucket, &dobj.object_name, &opts).is_ok()
@@ -10003,6 +10096,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
         let namespace_owner = (!is_meta_bucketname(bucket)).then(|| {
             Arc::new((
                 self.ctx.begin_namespace_commit(),
+                Arc::clone(&transaction_guards),
                 opts.delete_mutation_owner.clone(),
                 opts.object_lock_config_snapshot.clone(),
                 opts.scanner_publication_commit_scope.clone(),
@@ -10178,6 +10272,24 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
         }
 
         let results = join_all(futures).await;
+        if transaction_guards.values().any(|guard| guard.is_lock_lost()) {
+            for (index, object) in objects.iter().enumerate() {
+                if del_errs[index].is_none() {
+                    accounting[index] = None;
+                    del_errs[index] = Some(StorageError::NamespaceLockQuorumUnavailable {
+                        mode: "delete_transaction",
+                        bucket: bucket.to_owned(),
+                        object: object.object_name.clone(),
+                        required: 1,
+                        achieved: 0,
+                    });
+                }
+            }
+            if dist_erasure {
+                self.release_dist_delete_object_locks_batch(dist_batch_lock_ids).await;
+            }
+            return (del_objects, del_errs, accounting);
+        }
 
         let mut del_obj_errs: Vec<Vec<Option<DiskError>>> = vec![vec![None; objects.len()]; disks.len()];
 
@@ -10273,6 +10385,9 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                 let group = &vers[index];
                 let recovery_ticket = recovery_tickets[index].clone();
                 let namespace_owner = namespace_owner.clone();
+                let transaction_guard = transaction_guards
+                    .get(object_name_disk_identity(&group.name).as_ref())
+                    .cloned();
                 let disks = &disks;
                 let opts = &opts;
                 async move {
@@ -10293,6 +10408,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                             DeleteRecoveryContext {
                                 recovery_ticket,
                                 namespace_owner,
+                                transaction_guard,
                                 ..DeleteRecoveryContext::new(opts.expected_bucket_incarnation_id, &can_commit)
                             },
                         )
@@ -10339,7 +10455,11 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                 let object = fi_vers.name.clone();
                 let versions = fi_vers.clone();
                 let disk_namespace_owner = namespace_owner.clone();
+                let transaction_guard = transaction_guards.get(object_name_disk_identity(&object).as_ref()).cloned();
                 rollback_futures.push(async move {
+                    if transaction_guard.as_ref().is_some_and(|guard| guard.is_lock_lost()) {
+                        return;
+                    }
                     if should_rollback {
                         let errs = disk
                             .delete_versions_with_namespace_owner(
@@ -10415,7 +10535,16 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
             if del_errs[index].is_none() {
                 let object = &objects[index].object_name;
                 let result = match ensure_delete_commit_locks_held(None, bucket, object, &opts) {
-                    Ok(()) => self.reclaim_missing_delete_residue(bucket, object, &opts, None).await,
+                    Ok(()) => {
+                        self.reclaim_missing_delete_residue(
+                            bucket,
+                            object,
+                            &opts,
+                            None,
+                            transaction_guards.get(object_name_disk_identity(object).as_ref()),
+                        )
+                        .await
+                    }
                     Err(err) => Err(err),
                 };
                 if let Err(err) = result {
@@ -10424,6 +10553,13 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
             }
         }
 
+        // Deferred recovery takes fresh raw and transaction locks. Discard the
+        // completed leases' deadlines while retaining every caller-owned fence.
+        opts.namespace_lock_fence = outer_namespace_lock_fence;
+        // Release inner owners before reacquiring any raw key lock.
+        drop(namespace_owner);
+        drop(transaction_guards);
+
         // TODO(backlog): support partial object deletion for multi-part objects
 
         if dist_erasure {
@@ -10533,6 +10669,16 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
         } else {
             None
         };
+        // Lock order: the caller's raw object lock, then this target set's
+        // transaction key. The inner key remains distinct even when pool
+        // client quorums overlap, and no_lock never bypasses journal ownership.
+        let transaction_guard = if !is_meta_bucketname(bucket) && (!opts.delete_prefix || opts.delete_prefix_object) {
+            let guard = self.acquire_delete_transaction_lock(bucket, object).await?;
+            opts.add_namespace_lock_guard(&guard);
+            Some(guard)
+        } else {
+            None
+        };
         if opts.delete_prefix {
             let destructive_dispatch_phase = opts.lifecycle_delete_all.as_ref().is_none_or(|request| {
                 matches!(
@@ -10633,7 +10779,8 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                                 &delete_request,
                                 false,
                                 None,
-                                DeleteCommitContext::request(&opts, _lock_guard.as_ref()),
+                                DeleteCommitContext::request(&opts, _lock_guard.as_ref())
+                                    .with_transaction_guard(transaction_guard.as_ref()),
                             )
                             .await?;
                             if let Some((_, deleted_object)) = replication_delete {
@@ -10667,7 +10814,8 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                                 &delete_request,
                                 false,
                                 None,
-                                DeleteCommitContext::request(&opts, _lock_guard.as_ref()),
+                                DeleteCommitContext::request(&opts, _lock_guard.as_ref())
+                                    .with_transaction_guard(transaction_guard.as_ref()),
                             )
                             .await?;
                         }
@@ -10687,7 +10835,8 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                                 &delete_request,
                                 false,
                                 None,
-                                DeleteCommitContext::request(&opts, _lock_guard.as_ref()),
+                                DeleteCommitContext::request(&opts, _lock_guard.as_ref())
+                                    .with_transaction_guard(transaction_guard.as_ref()),
                             )
                             .await?;
                         }
@@ -10776,6 +10925,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                     bucket,
                     object,
                     DeleteRecoveryContext {
+                        transaction_guard: transaction_guard.clone(),
                         namespace_owner: Some(Arc::new((
                             self.ctx.begin_namespace_commit(),
                             _lock_guard.clone(),
@@ -10816,7 +10966,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                 if is_err_object_not_found(err) {
                     ensure_delete_commit_locks_held(_lock_guard.as_deref(), bucket, object, &opts)?;
                     if self
-                        .reclaim_missing_delete_residue(bucket, object, &opts, _lock_guard.as_ref())
+                        .reclaim_missing_delete_residue(bucket, object, &opts, _lock_guard.as_ref(), transaction_guard.as_ref())
                         .await?
                     {
                         if let Some(scope) = scanner_publication_commit_scope.as_ref() {
@@ -10866,7 +11016,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                 &dfi,
                 false,
                 None,
-                DeleteCommitContext::request(&opts, _lock_guard.as_ref()),
+                DeleteCommitContext::request(&opts, _lock_guard.as_ref()).with_transaction_guard(transaction_guard.as_ref()),
             )
             .await
             .map_err(|e| to_object_err(e, vec![bucket, object]))?;
@@ -10968,7 +11118,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
                 &fi,
                 should_force_delete_marker_for_missing_version(&opts),
                 delete_marker_purge.clone(),
-                DeleteCommitContext::request(&opts, _lock_guard.as_ref()),
+                DeleteCommitContext::request(&opts, _lock_guard.as_ref()).with_transaction_guard(transaction_guard.as_ref()),
             )
             .await
             .map_err(|e| to_object_err(e, vec![bucket, object]))?;
@@ -11033,7 +11183,7 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
             &dfi,
             opts.delete_marker,
             delete_marker_purge,
-            DeleteCommitContext::request(&opts, _lock_guard.as_ref()),
+            DeleteCommitContext::request(&opts, _lock_guard.as_ref()).with_transaction_guard(transaction_guard.as_ref()),
         )
         .await
         .map_err(|e| to_object_err(e, vec![bucket, object]))?;
@@ -11147,45 +11297,63 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
             }
         };
 
-        let (read_quorum, write_quorum) = match Self::object_quorum_from_meta(&metas, &errs, self.default_parity_count) {
-            Ok((read_quorum, write_quorum)) => (read_quorum, write_quorum),
+        let version_id = opts.version_id.as_deref().unwrap_or_default();
+        let quorum = Self::object_quorum_from_meta(&metas, &errs, self.default_parity_count);
+        let selection = match &quorum {
+            Ok((read_quorum, write_quorum)) => {
+                let read_quorum = usize::try_from(*read_quorum)
+                    .map_err(|_| to_object_err(DiskError::ErasureReadQuorum.into(), vec![bucket, object]))?;
+                let write_quorum = usize::try_from(*write_quorum)
+                    .map_err(|_| to_object_err(DiskError::ErasureWriteQuorum.into(), vec![bucket, object]))?;
+                Self::select_fileinfo_for_read(bucket, &disks, &metas, &errs, version_id, read_quorum, write_quorum)
+            }
+            Err(err) => Err(err.clone()),
+        };
+        let (online_disks, mut fi) = match selection {
+            Ok(selection) => selection,
             Err(mut err) => {
-                // A replication terminal CAS is a validation/write-back
-                // attempt, never a heal operation. In particular,
-                // ValidateOnly must remain zero-write, and a worker whose
-                // outer replication lease is already lost must not delete the
-                // surviving xl.meta copies before the namespace fence below
-                // can reject it. Leave dangling cleanup to heal/scanner.
-                if opts.replication_status_writeback.is_some() {
+                // The merged latest version can be one a failed PUT left below
+                // quorum; resolve it like a latest GET before the dangling
+                // cleanup below can report a key with a committed version absent.
+                // A replication terminal CAS stays side-effect free: the walk
+                // queues heal for the versions it skips, so it does not run.
+                let resolved = if opts.replication_status_writeback.is_none() {
+                    self.select_latest_past_dangling_versions(bucket, object, opts, false, &disks, &err)
+                        .await
+                } else {
+                    None
+                };
+                if let Some(snapshot) = resolved {
+                    let (fi, _, online_disks) = snapshot.into_owned();
+                    (online_disks, fi)
+                } else {
+                    // A replication terminal CAS is a validation/write-back
+                    // attempt, never a heal operation. In particular,
+                    // ValidateOnly must remain zero-write, and a worker whose
+                    // outer replication lease is already lost must not delete
+                    // the surviving xl.meta copies before the namespace fence
+                    // below can reject it. Leave dangling cleanup to
+                    // heal/scanner.
+                    if quorum.is_err()
+                        && opts.replication_status_writeback.is_none()
+                        && err == DiskError::ErasureReadQuorum
+                        && !bucket.starts_with(RUSTFS_META_BUCKET)
+                        && self
+                            .delete_if_dangling(bucket, object, &metas, &errs, &HashMap::new(), opts.clone())
+                            .await
+                            .is_ok()
+                    {
+                        if opts.version_id.is_some() {
+                            err = DiskError::FileVersionNotFound
+                        } else {
+                            err = DiskError::FileNotFound
+                        }
+                    }
                     return Err(to_object_err(err.into(), vec![bucket, object]));
                 }
-                if err == DiskError::ErasureReadQuorum
-                    && !bucket.starts_with(RUSTFS_META_BUCKET)
-                    && self
-                        .delete_if_dangling(bucket, object, &metas, &errs, &HashMap::new(), opts.clone())
-                        .await
-                        .is_ok()
-                {
-                    if opts.version_id.is_some() {
-                        err = DiskError::FileVersionNotFound
-                    } else {
-                        err = DiskError::FileNotFound
-                    }
-                }
-                return Err(to_object_err(err.into(), vec![bucket, object]));
             }
         };
 
-        let read_quorum =
-            usize::try_from(read_quorum).map_err(|_| to_object_err(DiskError::ErasureReadQuorum.into(), vec![bucket, object]))?;
-        let write_quorum = usize::try_from(write_quorum)
-            .map_err(|_| to_object_err(DiskError::ErasureWriteQuorum.into(), vec![bucket, object]))?;
-
-        let version_id = opts.version_id.as_deref().unwrap_or_default();
-        let (online_disks, mut fi) =
-            Self::select_fileinfo_for_read(bucket, &disks, &metas, &errs, version_id, read_quorum, write_quorum)
-                .map_err(|e| to_object_err(e.into(), vec![bucket, object]))?;
-
         if fi.deleted {
             return Err(to_object_err(Error::MethodNotAllowed, vec![bucket, object]));
         }
@@ -11790,13 +11958,12 @@ impl crate::storage_api_contracts::object::ObjectOperations for SetDisks {
         let bucket_lifecycle_guard = if let Some(expected_incarnation_id) = opts.expected_bucket_incarnation_id
             && opts.bucket_lifecycle_lock_fence.is_none()
         {
-            let guard = metadata_sys::object_store_in(&self.ctx)
-                .await?
-                .acquire_bucket_lifecycle_read_lock(bucket)
-                .await?;
-            self.validate_bucket_incarnation(bucket, expected_incarnation_id, opts)
-                .await?;
-            Some(guard)
+            Some(
+                metadata_sys::object_store_in(&self.ctx)
+                    .await?
+                    .acquire_bucket_incarnation_fence_with_options(bucket, expected_incarnation_id, Some(opts))
+                    .await?,
+            )
         } else {
             None
         };
@@ -25358,6 +25525,7 @@ mod delete_objects_lock_gating_tests {
     }
 
     #[tokio::test]
+    #[serial_test::serial]
     async fn delete_object_aborts_when_outer_lock_is_lost_at_commit() {
         let (_temp_dirs, disk_stores, set_disks) = hermetic_set_disks(4).await;
         let bucket = "single-lost-outer-lock";
@@ -25578,6 +25746,13 @@ mod delete_objects_lock_gating_tests {
             .as_fast_lock_manager()
             .expect("isolated fixture should use the local lock manager");
         let lock_metrics = lock_manager.get_metrics().shard_metrics;
+        let raw_key = ObjectKey::new(bucket, "obj-a");
+        let raw_holder = lock_manager.get_lock_info(&raw_key).expect("outer holder must be visible");
+        let transaction_key = ObjectKey::with_version(
+            bucket,
+            "obj-a",
+            format!("rustfs:delete-transaction:{}:{}", set_disks.pool_index, set_disks.set_index),
+        );
         assert_eq!(lock_manager.current_lock_counts(), (1, 0));
         let mut delete = Box::pin(set_disks.delete_objects(
             bucket,
@@ -25594,23 +25769,43 @@ mod delete_objects_lock_gating_tests {
         // than a second on CI without waiting for the namespace lock at all.
         let deletion = futures::future::poll_fn(|cx| {
             let result = std::future::Future::poll(delete.as_mut(), cx);
+            let current_holder = lock_manager.get_lock_info(&raw_key).expect("outer holder must remain held");
+            assert_eq!(
+                (current_holder.mode, &current_holder.owner, current_holder.acquired_at),
+                (raw_holder.mode, &raw_holder.owner, raw_holder.acquired_at),
+                "no_lock must preserve the original raw object holder"
+            );
+            let transaction_holder = lock_manager.get_lock_info(&transaction_key);
+            if let Some(holder) = &transaction_holder {
+                assert_eq!(holder.mode, rustfs_lock::LockMode::Exclusive);
+            }
             assert_eq!(
                 lock_manager.current_lock_counts(),
-                (1, 0),
-                "no_lock batch delete must preserve the outer holder without adding lock waiters"
+                (1 + u64::from(transaction_holder.is_some()), 0),
+                "only the distinct transaction owner may be added, without raw-key waiters"
             );
             let current = lock_manager.get_metrics().shard_metrics;
-            assert_eq!(
-                (current.total_acquisitions(), current.timeouts),
-                (lock_metrics.total_acquisitions(), lock_metrics.timeouts),
-                "no_lock batch delete must not acquire or time out on another namespace lock"
+            assert!(
+                current.total_acquisitions() <= lock_metrics.total_acquisitions() + 1,
+                "the transaction owner must be reused by inline recovery"
             );
+            assert_eq!(current.timeouts, lock_metrics.timeouts, "the raw key must never be reacquired");
             result
         });
         let (deleted, errs) = tokio::time::timeout(Duration::from_secs(30), deletion)
             .await
             .expect("no_lock batch delete disk work should complete");
 
+        assert_eq!(lock_manager.current_lock_counts(), (1, 0));
+        assert!(
+            lock_manager.get_lock_info(&transaction_key).is_none(),
+            "the transaction owner must be released"
+        );
+        assert_eq!(
+            lock_manager.get_metrics().shard_metrics.total_acquisitions(),
+            lock_metrics.total_acquisitions() + 1,
+            "no_lock still requires exactly one distinct transaction owner"
+        );
         assert!(errs[0].is_none(), "no_lock batch delete should not fail with a lock error: {:?}", errs[0]);
         assert!(deleted[0].found, "existing object must still be deleted");
         for disk in &disk_stores {

crates/ecstore/src/set_disk/read.rs

@@ -278,6 +278,10 @@ const MAX_DANGLING_LATEST_VERSIONS: usize = 8;
 #[derive(Clone, Copy, PartialEq, Eq)]
 enum DanglingRead {
     KeepQuorumError,
+    /// Metadata updates of the latest version keep the quorum error but, like
+    /// object reads, look past newer versions proven dangling
+    /// (`read_latest_past_dangling_versions`).
+    SkipDanglingVersions,
     ReportNotFound,
 }
 
@@ -729,9 +733,10 @@ impl SetDisks {
     }
 
     /// Like `get_object_fileinfo`, but `allow_early_stop=false` forces the full
-    /// quorum fanout. Read-before-write callers (object tagging) must use this:
-    /// the returned online-disk set is the write target, and the early-stop
-    /// subset would fail write quorum (backlog#872 regression fix).
+    /// quorum fanout. Read-before-write callers must use this or
+    /// `get_object_fileinfo_for_metadata_update`: the returned online-disk set
+    /// is the write target, and the early-stop subset would fail write quorum
+    /// (backlog#872 regression fix).
     #[tracing::instrument(level = "debug", skip(self))]
     pub(in crate::set_disk) async fn get_object_fileinfo_gated(
         &self,
@@ -753,6 +758,64 @@ impl SetDisks {
         .await
     }
 
+    /// The full-fanout read behind a metadata update such as object tagging.
+    /// A latest read whose newest versions never committed resolves to the
+    /// version a latest GET serves, while a dangling key keeps the quorum
+    /// error. The returned online disks are the write target.
+    #[tracing::instrument(level = "debug", skip(self))]
+    pub(in crate::set_disk) async fn get_object_fileinfo_for_metadata_update(
+        &self,
+        bucket: &str,
+        object: &str,
+        opts: &ObjectOptions,
+    ) -> Result<GetObjectFileInfo> {
+        self.get_object_fileinfo_gated_inner(
+            bucket,
+            object,
+            opts,
+            false,
+            false,
+            MetadataReadPurpose::FullLayout,
+            DanglingRead::SkipDanglingVersions,
+        )
+        .await
+    }
+
+    /// Recovers a failed latest selection in read-before-write callers that
+    /// read and select metadata themselves (`put_object_metadata` and the
+    /// CopyObject source) the way a latest GET does. `None` keeps the caller's
+    /// error: a failure other than read quorum, an explicit version, the
+    /// system bucket's commit-proof rule, or a walk that finds no readable
+    /// version or cannot read every drive. The selected metadata keeps its
+    /// part checksums because a version-only copy carries them into the new
+    /// version.
+    pub(in crate::set_disk) async fn select_latest_past_dangling_versions(
+        &self,
+        bucket: &str,
+        object: &str,
+        opts: &ObjectOptions,
+        read_data: bool,
+        disks: &[Option<DiskStore>],
+        err: &DiskError,
+    ) -> Option<GetObjectFileInfo> {
+        if *err != DiskError::ErasureReadQuorum || opts.version_id.is_some() || crate::bucket::utils::is_meta_bucketname(bucket) {
+            return None;
+        }
+        let opts = ObjectOptions {
+            include_part_checksums: true,
+            ..opts.clone()
+        };
+        Box::pin(self.read_latest_past_dangling_versions(
+            bucket,
+            object,
+            &opts,
+            read_data,
+            MetadataReadPurpose::FullLayout,
+            disks,
+        ))
+        .await
+    }
+
     #[allow(clippy::too_many_arguments)]
     async fn get_object_fileinfo_gated_inner(
         &self,
@@ -978,7 +1041,7 @@ impl SetDisks {
                 Err(err) => {
                     if err == DiskError::ErasureReadQuorum
                         && vid.is_empty()
-                        && dangling_read == DanglingRead::ReportNotFound
+                        && dangling_read != DanglingRead::KeepQuorumError
                         && metadata_fanout_complete
                         && !crate::bucket::utils::is_meta_bucketname(bucket)
                         && let Some(snapshot) =
@@ -9930,6 +9993,7 @@ mod dangling_read_tests {
     use crate::storage_api_contracts::bucket::{BucketOperations, MakeBucketOptions};
     use crate::storage_api_contracts::object::ObjectOperations;
     use http::HeaderMap;
+    use std::collections::HashMap;
     use std::path::PathBuf;
     use tempfile::TempDir;
     use tokio::io::AsyncReadExt;
@@ -10451,6 +10515,353 @@ mod dangling_read_tests {
         assert_ne!(latest.version_id, Some(v2));
     }
 
+    /// Version one on every drive under a version two that a failed PUT left
+    /// on drives `0..3`, below the read quorum of four.
+    async fn put_committed_below_dangling(set: &SetDisks, bucket: &str, object: &str) -> (Uuid, Uuid) {
+        let v1 = put(set, bucket, object, b"version one", true)
+            .await
+            .version_id
+            .expect("versioned PUT should assign a version id");
+        let v2 = put(set, bucket, object, b"version two", true)
+            .await
+            .version_id
+            .expect("versioned PUT should assign a version id");
+        drop_version_from(set, bucket, object, v2, 3..DRIVES).await;
+        (v1, v2)
+    }
+
+    /// Each drive's copy of `version_id`, or `None` where the drive lacks it.
+    async fn version_metadata(
+        set: &SetDisks,
+        bucket: &str,
+        object: &str,
+        version_id: Uuid,
+    ) -> Vec<Option<HashMap<String, String>>> {
+        let disks = set.disks.read().await.clone();
+        let mut copies = Vec::with_capacity(disks.len());
+        for disk in &disks {
+            let disk = disk.as_ref().expect("every drive should be online");
+            copies.push(
+                disk.read_version("", bucket, object, &version_id.to_string(), &ReadOptions::default())
+                    .await
+                    .ok()
+                    .map(|fi| fi.metadata),
+            );
+        }
+        copies
+    }
+
+    #[tokio::test]
+    async fn latest_tagging_skips_dangling_versions_above_a_committed_version() {
+        let bucket = "dangling-latest-tagging";
+        let object = "torn/latest";
+        let (_dirs, set) = dangling_test_set(bucket).await;
+        let (v1, v2) = put_committed_below_dangling(&set, bucket, object).await;
+        let tag_of = |metadata: &Option<HashMap<String, String>>| {
+            metadata
+                .as_ref()
+                .and_then(|metadata| metadata.get(rustfs_utils::http::headers::AMZ_OBJECT_TAGGING).cloned())
+        };
+
+        let tagged = set
+            .put_object_tags(bucket, object, "stage=committed", &ObjectOptions::default())
+            .await
+            .expect("PutObjectTagging must update the version a latest GET serves");
+        assert_eq!(tagged.version_id, Some(v1));
+        for (disk, metadata) in version_metadata(&set, bucket, object, v1).await.iter().enumerate() {
+            assert_eq!(
+                tag_of(metadata).as_deref(),
+                Some("stage=committed"),
+                "drive {disk} must carry the tag on version one"
+            );
+        }
+        for (disk, metadata) in version_metadata(&set, bucket, object, v2).await.iter().enumerate() {
+            assert_eq!(tag_of(metadata), None, "drive {disk} must leave the dangling version untouched");
+        }
+        assert_eq!(*head(&set, bucket, object, None).await.expect("latest HEAD").user_tags, "stage=committed");
+
+        let untagged = set
+            .delete_object_tags(bucket, object, &ObjectOptions::default())
+            .await
+            .expect("DeleteObjectTagging must update the version a latest GET serves");
+        assert_eq!(untagged.version_id, Some(v1));
+        for (disk, metadata) in version_metadata(&set, bucket, object, v1).await.iter().enumerate() {
+            assert_eq!(tag_of(metadata).as_deref(), Some(""), "drive {disk} must clear the tag on version one");
+        }
+    }
+
+    #[tokio::test]
+    async fn latest_metadata_update_skips_dangling_versions_above_a_committed_version() {
+        let bucket = "dangling-latest-metadata";
+        let object = "torn/latest";
+        let (_dirs, set) = dangling_test_set(bucket).await;
+        let (v1, v2) = put_committed_below_dangling(&set, bucket, object).await;
+
+        let updated = set
+            .put_object_metadata(
+                bucket,
+                object,
+                &ObjectOptions {
+                    versioned: true,
+                    eval_metadata: Some(HashMap::from([("x-amz-meta-probe".to_string(), "updated".to_string())])),
+                    ..Default::default()
+                },
+            )
+            .await
+            .expect("a latest metadata update must target the version a latest GET serves");
+        assert_eq!(updated.version_id, Some(v1));
+        assert!(updated.is_latest, "the updated version is the latest one");
+        for (disk, metadata) in version_metadata(&set, bucket, object, v1).await.iter().enumerate() {
+            let metadata = metadata.as_ref().expect("version one is on every drive");
+            assert_eq!(metadata.get("x-amz-meta-probe").map(String::as_str), Some("updated"), "drive {disk}");
+        }
+        for (disk, metadata) in version_metadata(&set, bucket, object, v2).await.iter().enumerate() {
+            assert!(
+                metadata
+                    .as_ref()
+                    .is_none_or(|metadata| !metadata.contains_key("x-amz-meta-probe")),
+                "drive {disk} must leave the dangling version untouched"
+            );
+        }
+    }
+
+    #[tokio::test]
+    async fn latest_copy_source_skips_dangling_versions_above_a_committed_version() {
+        let bucket = "dangling-latest-copy";
+        let (_dirs, set) = dangling_test_set(bucket).await;
+
+        // A metadata-only self-copy rewrites the latest version in place.
+        let object = "torn/in-place";
+        let (v1, _) = put_committed_below_dangling(&set, bucket, object).await;
+        let mut source = head(&set, bucket, object, None).await.expect("latest HEAD");
+        assert_eq!(source.version_id, Some(v1));
+        source.metadata_only = true;
+        source.user_defined = Arc::new(HashMap::from([("x-amz-meta-copied".to_string(), "in-place".to_string())]));
+        let copied = set
+            .copy_object(
+                bucket,
+                object,
+                bucket,
+                object,
+                &mut source,
+                &ObjectOptions::default(),
+                &ObjectOptions::default(),
+            )
+            .await
+            .expect("a CopyObject source without a version id must resolve like a latest GET");
+        assert_eq!(copied.version_id, Some(v1));
+        for (disk, metadata) in version_metadata(&set, bucket, object, v1).await.iter().enumerate() {
+            let metadata = metadata.as_ref().expect("version one is on every drive");
+            assert_eq!(metadata.get("x-amz-meta-copied").map(String::as_str), Some("in-place"), "drive {disk}");
+        }
+
+        // A version-only self-copy commits a new version that shares the
+        // served version's data.
+        let object = "torn/new-version";
+        let (_, v2) = put_committed_below_dangling(&set, bucket, object).await;
+        let v3 = Uuid::new_v4();
+        let mut source = head(&set, bucket, object, None).await.expect("latest HEAD");
+        source.version_only = true;
+        let copied = set
+            .copy_object(
+                bucket,
+                object,
+                bucket,
+                object,
+                &mut source,
+                &ObjectOptions {
+                    versioned: true,
+                    ..Default::default()
+                },
+                &ObjectOptions {
+                    version_id: Some(v3.to_string()),
+                    versioned: true,
+                    object_lock_config_snapshot: Some(Arc::new(crate::object_api::ObjectLockConfigSnapshot::new(
+                        crate::bucket::metadata_sys::ObjectLockConfigState::ConfirmedAbsent,
+                    ))),
+                    ..Default::default()
+                },
+            )
+            .await
+            .expect("a version-only CopyObject source without a version id must resolve like a latest GET");
+        assert_eq!(copied.version_id, Some(v3));
+        let latest = head(&set, bucket, object, None).await.expect("latest HEAD");
+        assert_eq!(latest.version_id, Some(v3));
+        assert_eq!(get(&set, bucket, object, None).await.expect("latest GET"), b"version one");
+        assert!(
+            version_metadata(&set, bucket, object, v2).await[..3]
+                .iter()
+                .all(Option::is_some),
+            "the copy must not remove the dangling version; heal owns its cleanup"
+        );
+    }
+
+    #[tokio::test]
+    async fn latest_metadata_update_past_dangling_versions_keeps_write_quorum() {
+        // EC 3+3: read quorum three, write quorum four. Version one reached
+        // three drives, so it is readable but below write quorum; versions two
+        // and three are dangling on two drives each. A latest read serves
+        // version one, and a metadata update of it is refused before writing.
+        let bucket = "dangling-latest-write-quorum";
+        let object = "torn/latest";
+        let (_dirs, set) = dangling_test_set_with(bucket, 6, 3).await;
+        let mut versions = Vec::new();
+        for body in [b"version zero".as_slice(), b"version one", b"version two", b"version three"] {
+            versions.push(
+                put(&set, bucket, object, body, true)
+                    .await
+                    .version_id
+                    .expect("versioned PUT should assign a version id"),
+            );
+        }
+        let [_, v1, v2, v3] = versions[..] else {
+            unreachable!("four versions were written");
+        };
+        drop_version_from(&set, bucket, object, v1, 3..6).await;
+        drop_version_from(&set, bucket, object, v2, 2..6).await;
+        drop_version_from(&set, bucket, object, v3, 0..3).await;
+        drop_version_from(&set, bucket, object, v3, 5..6).await;
+
+        let latest = head(&set, bucket, object, None)
+            .await
+            .expect("version one is readable at read quorum");
+        assert_eq!(latest.version_id, Some(v1));
+
+        let is_write_quorum_error =
+            |err: &StorageError| matches!(err, StorageError::ErasureWriteQuorum | StorageError::InsufficientWriteQuorum(_, _));
+        let Err(err) = set
+            .put_object_tags(bucket, object, "stage=refused", &ObjectOptions::default())
+            .await
+        else {
+            panic!("tagging a version below write quorum must be refused");
+        };
+        assert!(is_write_quorum_error(&err), "tagging keeps the write-quorum error: {err:?}");
+        let Err(err) = set
+            .put_object_metadata(
+                bucket,
+                object,
+                &ObjectOptions {
+                    versioned: true,
+                    eval_metadata: Some(HashMap::from([("x-amz-meta-probe".to_string(), "refused".to_string())])),
+                    ..Default::default()
+                },
+            )
+            .await
+        else {
+            panic!("a metadata update of a version below write quorum must be refused");
+        };
+        assert!(is_write_quorum_error(&err), "the metadata update keeps the write-quorum error: {err:?}");
+        let v4 = Uuid::new_v4();
+        let mut source = head(&set, bucket, object, None).await.expect("latest HEAD");
+        source.version_only = true;
+        let Err(err) = set
+            .copy_object(
+                bucket,
+                object,
+                bucket,
+                object,
+                &mut source,
+                &ObjectOptions {
+                    versioned: true,
+                    ..Default::default()
+                },
+                &ObjectOptions {
+                    version_id: Some(v4.to_string()),
+                    versioned: true,
+                    object_lock_config_snapshot: Some(Arc::new(crate::object_api::ObjectLockConfigSnapshot::new(
+                        crate::bucket::metadata_sys::ObjectLockConfigState::ConfirmedAbsent,
+                    ))),
+                    ..Default::default()
+                },
+            )
+            .await
+        else {
+            panic!("a version-only copy of a version below write quorum must be refused");
+        };
+        assert!(is_write_quorum_error(&err), "the version-only copy keeps the write-quorum error: {err:?}");
+        assert!(
+            version_metadata(&set, bucket, object, v4).await.iter().all(Option::is_none),
+            "a refused version-only copy must not write the new version to any drive"
+        );
+        for (disk, metadata) in version_metadata(&set, bucket, object, v1).await.iter().enumerate() {
+            assert!(
+                metadata.as_ref().is_none_or(|metadata| {
+                    !metadata.contains_key(rustfs_utils::http::headers::AMZ_OBJECT_TAGGING)
+                        && !metadata.contains_key("x-amz-meta-probe")
+                }),
+                "drive {disk} must not be written by a refused update"
+            );
+        }
+    }
+
+    #[tokio::test]
+    async fn replication_status_writeback_never_walks_past_dangling_versions() {
+        // A replication terminal CAS stays side-effect free: it keeps the
+        // read-quorum error instead of resolving the latest version, so it
+        // neither queues heal for the dangling version nor writes version one.
+        let bucket = "dangling-latest-replication-cas";
+        let object = "torn/latest";
+        let (_dirs, set) = dangling_test_set(bucket).await;
+        let (v1, _) = put_committed_below_dangling(&set, bucket, object).await;
+
+        let Err(err) = set
+            .put_object_metadata(
+                bucket,
+                object,
+                &ObjectOptions {
+                    versioned: true,
+                    eval_metadata: Some(HashMap::from([("x-amz-meta-probe".to_string(), "written".to_string())])),
+                    replication_status_writeback: Some(Box::new(crate::object_api::ReplicationStatusWritebackCondition {
+                        mode: crate::object_api::ReplicationStatusWritebackMode::ValidateOnly,
+                        ..Default::default()
+                    })),
+                    ..Default::default()
+                },
+            )
+            .await
+        else {
+            panic!("a replication terminal CAS must not resolve past a dangling version");
+        };
+        assert!(is_read_quorum_error(&err), "the CAS keeps the read-quorum error: {err:?}");
+        for (disk, metadata) in version_metadata(&set, bucket, object, v1).await.iter().enumerate() {
+            let metadata = metadata.as_ref().expect("version one is on every drive");
+            assert!(!metadata.contains_key("x-amz-meta-probe"), "drive {disk} must not be written");
+        }
+    }
+
+    #[tokio::test]
+    async fn latest_metadata_updates_past_dangling_versions_require_every_drive_to_answer() {
+        let bucket = "dangling-latest-update-offline";
+        let object = "torn/latest";
+        let (_dirs, set) = dangling_test_set(bucket).await;
+        put_committed_below_dangling(&set, bucket, object).await;
+        let offline = set.disks.write().await[5].take().expect("drive five should start online");
+
+        let Err(err) = set
+            .put_object_tags(bucket, object, "stage=uncertain", &ObjectOptions::default())
+            .await
+        else {
+            panic!("tagging must not resolve past a version an offline drive may commit");
+        };
+        assert!(is_read_quorum_error(&err), "tagging keeps the read-quorum error: {err:?}");
+        let Err(err) = set
+            .put_object_metadata(
+                bucket,
+                object,
+                &ObjectOptions {
+                    versioned: true,
+                    eval_metadata: Some(HashMap::from([("x-amz-meta-probe".to_string(), "uncertain".to_string())])),
+                    ..Default::default()
+                },
+            )
+            .await
+        else {
+            panic!("a metadata update must not resolve past a version an offline drive may commit");
+        };
+        assert!(is_read_quorum_error(&err), "the metadata update keeps the read-quorum error: {err:?}");
+        set.disks.write().await[5] = Some(offline);
+    }
+
     #[tokio::test]
     async fn dangling_classification_keeps_quorum_error_for_corrupt_metadata() {
         let bucket = "dangling-read-corrupt";

crates/ecstore/src/store/bucket.rs

@@ -448,6 +448,14 @@ impl ECStore {
         await_orphan_bucket_recovery(bucket, &publication_guard, &lifecycle_guard, &metadata_guard, &ns_guard, recover).await
     }
 
+    /// Read quota and bucket identity from one authoritative metadata snapshot.
+    pub async fn bucket_quota_and_incarnation_from_disk(
+        &self,
+        bucket: &str,
+    ) -> Result<(Option<crate::bucket::quota::BucketQuota>, Uuid, OffsetDateTime)> {
+        metadata_sys::get_quota_config_and_incarnation_from_disk_in(&self.ctx, bucket).await
+    }
+
     pub async fn get_bucket_metadata(&self, bucket: &str) -> Result<Arc<BucketMetadata>> {
         let sys = metadata_sys::require_bucket_metadata_sys_in(&self.ctx)?;
         sys.read().await.get(bucket).await
@@ -564,13 +572,83 @@ impl ECStore {
             .await
     }
 
-    pub(super) async fn acquire_bucket_incarnation_fence_with_options(
+    pub(crate) async fn acquire_bucket_incarnation_fence_with_options(
         &self,
         bucket: &str,
         expected: Uuid,
         opts: Option<&ObjectOptions>,
     ) -> Result<super::BucketIncarnationFenceGuard> {
+        Ok(self
+            .acquire_bucket_incarnation_fence_for_options(bucket, Some(expected), opts)
+            .await?
+            .0)
+    }
+
+    pub(crate) async fn acquire_bucket_incarnation_fence_for_options(
+        &self,
+        bucket: &str,
+        expected: Option<Uuid>,
+        opts: Option<&ObjectOptions>,
+    ) -> Result<(super::BucketIncarnationFenceGuard, Uuid)> {
         let inner = self.acquire_bucket_lifecycle_read_lock(bucket).await?;
+        self.validate_bucket_incarnation_fence_guard_with_options(bucket, inner, expected, opts)
+            .await
+    }
+
+    /// Acquire lexicographically ordered bucket lifecycle read locks for a copy
+    /// operation and validate both bucket incarnations through [`super::BucketFenceRegistry`].
+    pub async fn acquire_copy_bucket_incarnation_fences(
+        &self,
+        source_bucket: &str,
+        expected_source: Option<Uuid>,
+        destination_bucket: &str,
+        expected_destination: Option<Uuid>,
+    ) -> Result<(super::BucketIncarnationFenceGuard, Uuid, Option<super::BucketIncarnationFenceGuard>, Uuid)> {
+        let (source_guard, destination_guard) = if source_bucket == destination_bucket {
+            (self.acquire_bucket_lifecycle_read_lock(source_bucket).await?, None)
+        } else if source_bucket < destination_bucket {
+            let source_guard = self.acquire_bucket_lifecycle_read_lock(source_bucket).await?;
+            let destination_guard = self.acquire_bucket_lifecycle_read_lock(destination_bucket).await?;
+            (source_guard, Some(destination_guard))
+        } else {
+            let destination_guard = self.acquire_bucket_lifecycle_read_lock(destination_bucket).await?;
+            let source_guard = self.acquire_bucket_lifecycle_read_lock(source_bucket).await?;
+            (source_guard, Some(destination_guard))
+        };
+        let (source_guard, current_source_incarnation_id) = self
+            .validate_bucket_incarnation_fence_guard_with_options(source_bucket, source_guard, expected_source, None)
+            .await?;
+        let (destination_guard, current_destination_incarnation_id) = if let Some(destination_guard) = destination_guard {
+            let (destination_guard, destination_incarnation_id) = self
+                .validate_bucket_incarnation_fence_guard_with_options(
+                    destination_bucket,
+                    destination_guard,
+                    expected_destination,
+                    None,
+                )
+                .await?;
+            (Some(destination_guard), destination_incarnation_id)
+        } else {
+            if expected_destination.is_some_and(|expected| expected != current_source_incarnation_id) {
+                return Err(StorageError::BucketNotFound(destination_bucket.to_owned()));
+            }
+            (None, current_source_incarnation_id)
+        };
+        Ok((
+            source_guard,
+            current_source_incarnation_id,
+            destination_guard,
+            current_destination_incarnation_id,
+        ))
+    }
+
+    async fn validate_bucket_incarnation_fence_guard_with_options(
+        &self,
+        bucket: &str,
+        inner: rustfs_lock::NamespaceLockGuard,
+        expected: Option<Uuid>,
+        opts: Option<&ObjectOptions>,
+    ) -> Result<(super::BucketIncarnationFenceGuard, Uuid)> {
         let mut guard = super::BucketIncarnationFenceGuard::new(
             Arc::clone(&self.bucket_fence_registry),
             bucket,
@@ -586,10 +664,10 @@ impl ECStore {
                 }
             })
             .await?;
-        if current != expected {
+        if expected.is_some_and(|expected| current != expected) {
             return Err(StorageError::BucketNotFound(bucket.to_owned()));
         }
-        Ok(guard)
+        Ok((guard, current))
     }
 
     /// Hold this guard through recursive-delete authorization and mutation so

crates/ecstore/src/store/bucket_fence.rs

@@ -149,6 +149,18 @@ impl BucketFenceRegistry {
             }
         }
     }
+
+    /// Return the memoized incarnation id for `bucket` when at least one
+    /// registered lifecycle read guard is currently held without lock loss.
+    pub(crate) fn validated_incarnation(&self, bucket: &str) -> Option<Uuid> {
+        let mut entries = self.entries.lock().expect("bucket fence registry poisoned");
+        let entry = entries.get_mut(bucket)?;
+        if entry.guards.iter().any(|guard| guard.loss_probe.is_lost()) {
+            entry.validated = None;
+            return None;
+        }
+        entry.validated
+    }
 }
 
 /// Owns continuous lifecycle coverage and its incarnation validation memo.
@@ -221,7 +233,7 @@ impl BucketIncarnationFenceGuard {
         }
     }
 
-    pub(crate) fn is_lock_lost(&self) -> bool {
+    pub fn is_lock_lost(&self) -> bool {
         self.inner.as_ref().is_some_and(NamespaceLockGuard::is_lock_lost)
     }
 
@@ -310,9 +322,16 @@ mod tests {
         let (first_probe, first_lost) = controllable_probe();
         let first = reg.enter("b", first_probe);
         assert_eq!(first.memoized, None);
+        assert_eq!(reg.validated_incarnation("b"), None);
         reg.memoize("b", uuid(7));
+        assert_eq!(reg.validated_incarnation("b"), Some(uuid(7)));
 
         first_lost.store(true, std::sync::atomic::Ordering::SeqCst);
+        assert_eq!(
+            reg.validated_incarnation("b"),
+            None,
+            "live lost guard must clear and block validated_incarnation"
+        );
 
         let second = reg.enter("b", live_probe());
         assert_eq!(second.memoized, None, "live lost guard must force disk revalidation");
@@ -320,9 +339,11 @@ mod tests {
 
         let third = reg.enter("b", live_probe());
         assert_eq!(third.memoized, None, "memo remains blocked while the lost guard is live");
+        assert_eq!(reg.validated_incarnation("b"), None);
 
         reg.exit("b", first.token, true);
         reg.memoize("b", uuid(8));
+        assert_eq!(reg.validated_incarnation("b"), Some(uuid(8)));
         let fourth = reg.enter("b", live_probe());
         assert_eq!(fourth.memoized, Some(uuid(8)), "memo resumes after lost coverage leaves");
 

crates/ecstore/src/store/init.rs

@@ -21384,6 +21384,141 @@ mod tests {
         shutdown.cancel();
     }
 
+    #[tokio::test]
+    #[serial_test::serial(storage_class_env)]
+    async fn put_object_metadata_and_copy_object_reuse_overlapping_incarnation_fence() {
+        let temp = tempfile::tempdir().expect("create metadata/copy fence store");
+        let (_ctx, store, shutdown) =
+            without_storage_class_env(build_isolated_test_store(temp.path(), "metadata-copy-fence-reuse", &[4])).await;
+        crate::bucket::metadata_sys::init_bucket_metadata_sys(store.clone(), Vec::new()).await;
+        let bucket = format!("metadata-copy-fence-{}", Uuid::new_v4());
+        store
+            .make_bucket(&bucket, &MakeBucketOptions::default())
+            .await
+            .expect("create bucket");
+        let mut seed_reader = PutObjReader::from_vec(b"seed payload".to_vec());
+        let versioned_opts = ObjectOptions {
+            versioned: true,
+            ..Default::default()
+        };
+        let mut src_info = store
+            .put_object(&bucket, "src.bin", &mut seed_reader, &versioned_opts)
+            .await
+            .expect("seed source object");
+        let src_version_id = src_info
+            .version_id
+            .expect("versioned PUT should return a version ID")
+            .to_string();
+        let expected = store.bucket_incarnation_id(&bucket).await.expect("read incarnation");
+        let coverage = store
+            .acquire_bucket_incarnation_fence(&bucket, expected)
+            .await
+            .expect("validate continuous coverage");
+        let metadata_writer = crate::bucket::metadata_sys::acquire_bucket_metadata_transaction_lock_in(&store.ctx, &bucket)
+            .await
+            .expect("hold metadata writer during covered metadata and copy operations");
+
+        let updated = tokio::time::timeout(
+            Duration::from_secs(10),
+            store.put_object_metadata(
+                &bucket,
+                "src.bin",
+                &ObjectOptions {
+                    version_id: Some(src_version_id.clone()),
+                    versioned: true,
+                    eval_metadata: Some(HashMap::from([("x-amz-meta-fenced".to_string(), "true".to_string())])),
+                    ..Default::default()
+                },
+            ),
+        )
+        .await
+        .expect("covered put_object_metadata must not reacquire the metadata transaction lock")
+        .expect("update object metadata using authoritative memo");
+        assert_eq!(updated.user_defined.get("x-amz-meta-fenced").map(String::as_str), Some("true"));
+
+        Arc::make_mut(&mut src_info.user_defined).insert("x-amz-meta-copied".to_string(), "true".to_string());
+        let src_copy_opts = ObjectOptions {
+            version_id: Some(src_version_id),
+            versioned: true,
+            ..Default::default()
+        };
+        let copied = tokio::time::timeout(
+            Duration::from_secs(10),
+            store.copy_object(&bucket, "src.bin", &bucket, "src.bin", &mut src_info, &src_copy_opts, &versioned_opts),
+        )
+        .await
+        .expect("covered versioned copy_object must not reacquire the metadata transaction lock")
+        .expect("versioned copy using authoritative memo");
+        assert_eq!(copied.user_defined.get("x-amz-meta-copied").map(String::as_str), Some("true"));
+
+        let (src_guard, src_incarnation, dst_guard, dst_incarnation) = tokio::time::timeout(
+            Duration::from_secs(10),
+            store.acquire_copy_bucket_incarnation_fences(&bucket, Some(expected), &bucket, Some(expected)),
+        )
+        .await
+        .expect("covered acquire_copy_bucket_incarnation_fences must not reacquire the metadata transaction lock")
+        .expect("validate same-bucket copy fences using authoritative memo");
+        assert!(dst_guard.is_none());
+        assert_eq!(src_incarnation, expected);
+        assert_eq!(dst_incarnation, expected);
+        let mut borrowed_fence_opts = ObjectOptions {
+            expected_bucket_incarnation_id: Some(expected),
+            ..Default::default()
+        };
+        src_guard.attach_to_object_options(&mut borrowed_fence_opts);
+        let fenced_incarnation = tokio::time::timeout(
+            Duration::from_secs(10),
+            crate::bucket::metadata_sys::get_bucket_incarnation_id_for_options_in(&store.ctx, &bucket, &borrowed_fence_opts),
+        )
+        .await
+        .expect("borrowed fence under active coverage must not reacquire the metadata transaction lock")
+        .expect("resolve incarnation under borrowed fence");
+        assert_eq!(fenced_incarnation, expected);
+        assert!(
+            matches!(
+                store
+                    .acquire_copy_bucket_incarnation_fences(&bucket, Some(expected), &bucket, Some(Uuid::new_v4()))
+                    .await,
+                Err(StorageError::BucketNotFound(_))
+            ),
+            "same-bucket copy fence must reject a mismatched destination incarnation"
+        );
+        drop(src_guard);
+
+        let stale_opts = ObjectOptions {
+            expected_bucket_incarnation_id: Some(Uuid::new_v4()),
+            versioned: true,
+            ..Default::default()
+        };
+        assert!(
+            matches!(
+                store.put_object_metadata(&bucket, "src.bin", &stale_opts).await,
+                Err(StorageError::BucketNotFound(_))
+            ),
+            "put_object_metadata must reject a stale expected incarnation even under warm coverage"
+        );
+        assert!(
+            matches!(
+                store
+                    .copy_object(
+                        &bucket,
+                        "src.bin",
+                        &bucket,
+                        "src.bin",
+                        &mut src_info,
+                        &ObjectOptions::default(),
+                        &stale_opts,
+                    )
+                    .await,
+                Err(StorageError::BucketNotFound(_))
+            ),
+            "copy_object must reject a stale expected incarnation even under warm coverage"
+        );
+        drop(metadata_writer);
+        drop(coverage);
+        shutdown.cancel();
+    }
+
     #[tokio::test]
     #[serial_test::serial(storage_class_env)]
     async fn multipart_snapshot_bypasses_initializer_queued_behind_metadata_writer() {
@@ -21469,10 +21604,25 @@ mod tests {
             .acquire_bucket_incarnation_fence(&bucket, old)
             .await
             .expect("validate with no-op lock");
+        let snapshot = store
+            .object_lock_config_snapshot_under_lifecycle_fence(&bucket, &crate::object_api::NamespaceLockFence::new())
+            .await
+            .expect("capture snapshot under no-op lock");
         let current = Uuid::new_v4();
         crate::bucket::metadata::save_bucket_incarnation(store.clone(), &bucket, current)
             .await
             .expect("replace authority while no-op guard provides no exclusion");
+        let snapshot_opts = ObjectOptions {
+            expected_bucket_incarnation_id: Some(old),
+            object_lock_config_snapshot: Some(snapshot),
+            ..Default::default()
+        };
+        assert_eq!(
+            crate::bucket::metadata_sys::get_bucket_incarnation_id_for_options_in(&store.ctx, &bucket, &snapshot_opts)
+                .await
+                .expect("disabled lock manager must re-read incarnation from disk instead of trusting snapshot"),
+            current
+        );
         assert!(
             matches!(
                 store.acquire_bucket_incarnation_fence(&bucket, old).await,

crates/ecstore/src/store/list_objects.rs

@@ -1030,16 +1030,19 @@ impl ECStore {
         // Lock order matches writes: bucket lifecycle, metadata validation,
         // then object namespace. Borrow fences supplied by an outer operation.
         let bucket_guard = if opts.bucket_lifecycle_lock_fence.is_none() {
-            let guard = self.acquire_bucket_lifecycle_read_lock(bucket).await?;
-            opts.add_bucket_lifecycle_lock_guard(&guard);
+            let guard = self
+                .acquire_bucket_incarnation_fence_with_options(bucket, bucket_incarnation_id, Some(&opts))
+                .await?;
+            guard.attach_to_object_options(&mut opts);
             Some(guard)
         } else {
+            let incarnation =
+                crate::bucket::metadata_sys::get_bucket_incarnation_id_for_options_in(&self.ctx, bucket, &opts).await?;
+            if incarnation != bucket_incarnation_id {
+                return Err(Error::BucketNotFound(bucket.to_owned()));
+            }
             None
         };
-        let incarnation = crate::bucket::metadata_sys::get_bucket_incarnation_id_for_options_in(&self.ctx, bucket, &opts).await?;
-        if incarnation != bucket_incarnation_id {
-            return Err(Error::BucketNotFound(bucket.to_owned()));
-        }
         let metadata_sys = crate::bucket::metadata_sys::bucket_metadata_sys_of(&self.ctx)?;
         let metadata_sys = metadata_sys.read().await.clone();
         let (versioning, _) = metadata_sys.get_versioning_config(bucket).await?;

crates/ecstore/src/store/multipart.rs

@@ -412,7 +412,7 @@ impl ECStore {
 
     /// Multipart lock order is bucket lifecycle, generation validation, then
     /// object/upload locks in the selected set.
-    async fn guard_multipart_bucket_incarnation(
+    pub(super) async fn guard_multipart_bucket_incarnation(
         &self,
         bucket: &str,
         opts: &ObjectOptions,

crates/ecstore/src/store/object.rs

@@ -30,8 +30,8 @@ use crate::bucket::lifecycle::{
     },
 };
 use crate::bucket::metadata_sys::{
-    acquire_bucket_metadata_transaction_read_lock_in, get_bucket_incarnation_id_for_options_in,
-    get_cached_bucket_incarnation_id_in, get_delete_config_from_disk_in, get_object_lock_config_and_incarnation_from_disk_in,
+    acquire_bucket_metadata_transaction_read_lock_in, get_cached_bucket_incarnation_id_in, get_delete_config_from_disk_in,
+    get_object_lock_config_and_incarnation_from_disk_in,
 };
 use crate::bucket::object_lock::objectlock_sys::{
     check_object_lock_for_deletion_with_state, ensure_recursive_force_delete_allowed_for_state,
@@ -4883,24 +4883,20 @@ impl ECStore {
         if !is_meta_bucketname(dst_bucket) && dst_opts.expected_bucket_incarnation_id.is_none() {
             dst_opts.expected_bucket_incarnation_id = Some(self.bucket_incarnation_id(dst_bucket).await?);
         }
-        let _bucket_lifecycle_guard = if is_meta_bucketname(dst_bucket) || dst_opts.bucket_lifecycle_lock_fence.is_some() {
-            None
-        } else {
-            Some(self.acquire_bucket_lifecycle_read_lock(dst_bucket).await?)
-        };
-        let current_bucket_incarnation_id = if let Some(guard) = _bucket_lifecycle_guard.as_ref() {
-            dst_opts.add_bucket_lifecycle_lock_guard(guard);
-            let current_incarnation_id = get_bucket_incarnation_id_for_options_in(&self.ctx, dst_bucket, &dst_opts).await?;
-            if dst_opts
-                .expected_bucket_incarnation_id
-                .is_some_and(|expected| expected != current_incarnation_id)
-            {
-                return Err(StorageError::BucketNotFound(dst_bucket.to_string()));
-            }
-            Some(current_incarnation_id)
-        } else {
-            dst_opts.expected_bucket_incarnation_id
-        };
+        let (_bucket_lifecycle_guard, current_bucket_incarnation_id) =
+            if is_meta_bucketname(dst_bucket) || dst_opts.bucket_lifecycle_lock_fence.is_some() {
+                (None, dst_opts.expected_bucket_incarnation_id)
+            } else {
+                let (guard, current_incarnation_id) = self
+                    .acquire_bucket_incarnation_fence_for_options(
+                        dst_bucket,
+                        dst_opts.expected_bucket_incarnation_id,
+                        Some(&dst_opts),
+                    )
+                    .await?;
+                guard.attach_to_object_options(&mut dst_opts);
+                (Some(guard), Some(current_incarnation_id))
+            };
         if dst_opts
             .bucket_lifecycle_lock_fence
             .as_ref()
@@ -6504,24 +6500,8 @@ impl ECStore {
         opts: &ObjectOptions,
     ) -> Result<()> {
         let object = encode_dir_object(object);
-        let mut opts = transition_restore_pool_opts(opts);
-        if !is_meta_bucketname(bucket) && opts.expected_bucket_incarnation_id.is_none() {
-            opts.expected_bucket_incarnation_id = Some(self.bucket_incarnation_id(bucket).await?);
-        }
-        let bucket_lifecycle_guard = if is_meta_bucketname(bucket) {
-            None
-        } else {
-            Some(self.acquire_bucket_lifecycle_read_lock(bucket).await?)
-        };
-        if let Some(guard) = bucket_lifecycle_guard.as_ref() {
-            opts.add_bucket_lifecycle_lock_guard(guard);
-        }
-        if !is_meta_bucketname(bucket) {
-            let current_incarnation_id = get_bucket_incarnation_id_for_options_in(&self.ctx, bucket, &opts).await?;
-            if opts.expected_bucket_incarnation_id != Some(current_incarnation_id) {
-                return Err(StorageError::BucketNotFound(bucket.to_string()));
-            }
-        }
+        let opts = transition_restore_pool_opts(opts);
+        let (mut opts, _bucket_lifecycle_guard) = self.guard_multipart_bucket_incarnation(bucket, &opts).await?;
         if opts.overwrites_existing_version() && !is_meta_bucketname(bucket) {
             let expected_incarnation_id = opts
                 .expected_bucket_incarnation_id
@@ -6589,16 +6569,11 @@ impl ECStore {
         let bucket_lifecycle_guard = if is_meta_bucketname(bucket) {
             None
         } else {
-            let guard = self.acquire_bucket_lifecycle_read_lock(bucket).await?;
-            let current_incarnation_id = get_bucket_incarnation_id_for_options_in(&self.ctx, bucket, &opts).await?;
-            if opts
-                .expected_bucket_incarnation_id
-                .is_some_and(|expected| expected != current_incarnation_id)
-            {
-                return Err(StorageError::BucketNotFound(bucket.to_string()));
-            }
+            let (guard, current_incarnation_id) = self
+                .acquire_bucket_incarnation_fence_for_options(bucket, opts.expected_bucket_incarnation_id, Some(&opts))
+                .await?;
             opts.expected_bucket_incarnation_id = Some(current_incarnation_id);
-            opts.add_bucket_lifecycle_lock_guard(&guard);
+            guard.attach_to_object_options(&mut opts);
             if guard.is_lock_lost() {
                 return Err(Error::other("bucket lifecycle lock was lost before the metadata update"));
             }
@@ -13167,6 +13142,202 @@ mod tests {
         })
         .await;
     }
+
+    async fn assert_delete_excludes_recovery_across_pool_lock_domains(topology: &str, batch: bool) {
+        let ctx = Arc::new(crate::runtime::instance::InstanceContext::new());
+        let (_first_dirs, first_set) = make_local_set_disks_with_ctx(4, 2, Arc::clone(&ctx)).await;
+        let (_second_dirs, second_set) = make_local_set_disks_with_ctx(4, 2, Arc::clone(&ctx)).await;
+        let mut store = new_prepared_reader_test_store_with_ctx(&[first_set, second_set], Arc::clone(&ctx)).await;
+        let clients: Vec<Arc<dyn rustfs_lock::LockClient>> = (0..4)
+            .map(|_| {
+                Arc::new(rustfs_lock::LocalClient::with_manager(Arc::new(rustfs_lock::GlobalLockManager::Enabled(
+                    Arc::new(rustfs_lock::FastObjectLockManager::new()),
+                )))) as Arc<dyn rustfs_lock::LockClient>
+            })
+            .collect();
+        let domains = match topology {
+            "disjoint" => [vec![clients[0].clone()], vec![clients[1].clone()]],
+            "identical" => [clients[..3].to_vec(), clients[..3].to_vec()],
+            "overlapping" => [clients[..3].to_vec(), clients[1..].to_vec()],
+            _ => panic!("unknown lock topology"),
+        };
+        for (pool, lockers) in store.pools.iter_mut().zip(domains) {
+            let mut set = (*pool.disk_set[0]).clone();
+            set.lockers = lockers;
+            Arc::make_mut(pool).disk_set[0] = Arc::new(set);
+        }
+        let store = Arc::new(store);
+        crate::bucket::metadata_sys::init_bucket_metadata_sys(Arc::clone(&store), Vec::new()).await;
+        let bucket = "delete-nonzero-pool-lock";
+        let object = "object.bin";
+        store
+            .handle_make_bucket(bucket, &MakeBucketOptions::default())
+            .await
+            .expect("create the bucket in both pools");
+        if batch {
+            // Latest-marker routing sends this batch only to the nonzero pool,
+            // so the cleanup barrier observes its prepared journal directly.
+            store
+                .update_bucket_metadata_config(
+                    bucket,
+                    crate::bucket::metadata::BUCKET_VERSIONING_CONFIG,
+                    b"<VersioningConfiguration><Status>Enabled</Status></VersioningConfiguration>".to_vec(),
+                )
+                .await
+                .expect("enable versioning for the routed batch");
+        }
+        let target = store.pools[1].get_disks_by_key(object);
+        let source = target
+            .put_object(
+                bucket,
+                object,
+                &mut PutObjReader::from_vec(b"delete lock regression".to_vec()),
+                &ObjectOptions {
+                    versioned: batch,
+                    ..Default::default()
+                },
+            )
+            .await
+            .expect("seed an object only in the nonzero pool");
+        ctx.update_erasure_type(SetupType::DistErasure).await;
+
+        let object_barrier = (!batch).then(|| crate::set_disk::DeleteObjectCommitBarrier::install(bucket, object));
+        let batch_barrier = batch.then(|| crate::set_disk::DeleteCleanupBarrier::install(bucket));
+        let delete_store = Arc::clone(&store);
+        let delete = tokio::spawn(async move {
+            if batch {
+                let (_, errors) = delete_store
+                    .delete_objects(
+                        bucket,
+                        vec![ObjectToDelete {
+                            object_name: object.to_owned(),
+                            ..Default::default()
+                        }],
+                        ObjectOptions::default(),
+                    )
+                    .await;
+                match errors.into_iter().flatten().next() {
+                    Some(error) => Err(error),
+                    None => Ok(()),
+                }
+            } else {
+                delete_store
+                    .delete_object(bucket, object, ObjectOptions::default())
+                    .await
+                    .map(|_| ())
+            }
+        });
+        if let Some(barrier) = &object_barrier {
+            barrier.wait_until_paused().await;
+        }
+        if let Some(barrier) = &batch_barrier {
+            barrier.wait_until_paused().await;
+        }
+        let recovery_store = Arc::clone(&store);
+        let mut recovery = tokio::spawn(async move {
+            recovery_store
+                .recover_delete_transactions_at_incarnation(
+                    bucket,
+                    Some(object),
+                    None,
+                    &HealOpts {
+                        pool: Some(1),
+                        set: Some(0),
+                        ..Default::default()
+                    },
+                )
+                .await
+        });
+        let early_recovery = tokio::time::timeout(Duration::from_millis(100), &mut recovery).await;
+        let recovery_was_blocked = early_recovery.is_err();
+        if let Some(barrier) = &object_barrier {
+            barrier.release();
+        }
+        if let Some(barrier) = &batch_barrier {
+            barrier.release();
+        }
+        tokio::time::timeout(Duration::from_secs(10), delete)
+            .await
+            .expect("the delete should finish after releasing its commit barrier")
+            .expect("the delete task should join")
+            .expect("the delete should succeed");
+        let recovered = match early_recovery {
+            Ok(result) => result,
+            Err(_) => tokio::time::timeout(Duration::from_secs(10), recovery)
+                .await
+                .expect("recovery should finish after the frontend delete"),
+        };
+        recovered
+            .expect("the recovery task should join")
+            .expect("recovery should succeed");
+        assert!(
+            recovery_was_blocked,
+            "recovery must not inspect an in-flight frontend delete with {topology} pool lock clients"
+        );
+        if batch {
+            let marker = target
+                .get_object_info(bucket, object, &ObjectOptions::default())
+                .await
+                .expect("the versioned batch must publish a current delete marker");
+            assert!(marker.delete_marker && marker.is_latest);
+            assert_eq!(marker.num_versions, 2, "the source version must remain beside the new marker");
+            assert_ne!(marker.version_id, source.version_id);
+            let mut reader = target
+                .get_object_reader(
+                    bucket,
+                    object,
+                    None,
+                    HeaderMap::new(),
+                    &ObjectOptions {
+                        version_id: Some(source.version_id.expect("versioned source identity").to_string()),
+                        ..Default::default()
+                    },
+                )
+                .await
+                .expect("the original source version must remain readable");
+            let mut body = Vec::new();
+            reader
+                .stream
+                .read_to_end(&mut body)
+                .await
+                .expect("read the retained source version");
+            assert_eq!(body, b"delete lock regression");
+        } else {
+            let error = target
+                .get_object_info(bucket, object, &ObjectOptions::default())
+                .await
+                .expect_err("the deleted object must be absent");
+            assert!(is_err_object_not_found(&error));
+        }
+    }
+
+    #[tokio::test]
+    #[serial_test::serial]
+    #[serial_test::serial(storage_class_env)]
+    async fn batch_delete_excludes_recovery_on_nonzero_pool() {
+        assert_delete_excludes_recovery_across_pool_lock_domains("disjoint", true).await;
+    }
+
+    #[tokio::test]
+    #[serial_test::serial]
+    #[serial_test::serial(storage_class_env)]
+    async fn delete_excludes_recovery_with_disjoint_pool_lock_clients() {
+        assert_delete_excludes_recovery_across_pool_lock_domains("disjoint", false).await;
+    }
+
+    #[tokio::test]
+    #[serial_test::serial]
+    #[serial_test::serial(storage_class_env)]
+    async fn delete_excludes_recovery_with_identical_pool_lock_clients() {
+        assert_delete_excludes_recovery_across_pool_lock_domains("identical", false).await;
+    }
+
+    #[tokio::test]
+    #[serial_test::serial]
+    #[serial_test::serial(storage_class_env)]
+    async fn delete_excludes_recovery_with_overlapping_pool_lock_clients() {
+        assert_delete_excludes_recovery_across_pool_lock_domains("overlapping", false).await;
+    }
 }
 
 #[cfg(test)]

crates/heal/src/error.rs

@@ -16,7 +16,7 @@ use rustfs_io_metrics::internode_metrics::INTERNODE_OPERATION_PUT_FILE_STREAM;
 use rustfs_rio::{InternodeHttpError, InternodeHttpErrorKind};
 use thiserror::Error;
 
-use super::heal::{DiskError, EcstoreError};
+use super::heal::{DiskError, EcstoreError, storage_api::owner::EcstorePoolMetadataFailure};
 
 const HEAL_DANGLING_DELETE_GRACE_MESSAGE: &str = "dangling object deletion deferred by heal grace window";
 pub(crate) const MRF_MISSING_PROOF_PREFIX: &str = "Missing exact storage proof for durable MRF repair ";
@@ -236,6 +236,14 @@ pub(crate) fn classify_heal_error(error: &Error) -> HealErrorClass {
 /// with object absence, the conflation that once let an offline drive be
 /// recorded as absent and skipped (backlog#856 / #799 B7).
 pub(crate) fn classify_storage_error(error: &EcstoreError) -> HealErrorClass {
+    if let Some(failure) = error.pool_metadata_failure() {
+        return match failure.kind {
+            EcstorePoolMetadataFailure::ReadUnavailable | EcstorePoolMetadataFailure::TransactionUnknown => {
+                HealErrorClass::Transient
+            }
+            EcstorePoolMetadataFailure::RecoveryRequired | EcstorePoolMetadataFailure::FenceLost => HealErrorClass::Permanent,
+        };
+    }
     if let EcstoreError::Lock(lock_error) = error {
         return if lock_error.is_fatal() {
             HealErrorClass::Permanent
@@ -435,6 +443,34 @@ mod tests {
     use super::Error;
     use crate::heal::{DiskError, EcstoreError};
 
+    #[test]
+    fn pool_metadata_failures_keep_their_typed_recovery_classification() {
+        use crate::heal::storage_api::owner::{EcstorePoolMetadataError, EcstorePoolMetadataFailure};
+
+        for (kind, retryable) in [
+            (EcstorePoolMetadataFailure::ReadUnavailable, true),
+            (EcstorePoolMetadataFailure::TransactionUnknown, true),
+            (EcstorePoolMetadataFailure::RecoveryRequired, false),
+            (EcstorePoolMetadataFailure::FenceLost, false),
+        ] {
+            let error = EcstoreError::other(EcstorePoolMetadataError {
+                kind,
+                operation: "bucket heal".to_owned(),
+                phase: "native_heal",
+                since: std::time::UNIX_EPOCH.into(),
+                source: Some(std::sync::Arc::new(EcstoreError::SlowDown)),
+            });
+            let text = error.to_string();
+            for error in [error.clone(), error] {
+                assert_eq!(Error::Storage(error).is_recoverable_heal(), retryable, "{kind:?}");
+            }
+            assert!(
+                !Error::Storage(EcstoreError::other(text)).is_recoverable_heal(),
+                "display text must not grant recovery authority"
+            );
+        }
+    }
+
     #[test]
     fn namespace_lock_quorum_is_recoverable_across_io_error_conversions() {
         for (required, achieved) in [(2, 1), (1, 0)] {

crates/heal/src/heal/storage_api.rs

@@ -26,7 +26,11 @@ pub(crate) use rustfs_ecstore::api::disk::{
     RUSTFS_META_BUCKET as ECSTORE_RUSTFS_META_BUCKET, ReplacementExecutionLease as EcstoreReplacementExecutionLease,
 };
 pub(crate) use rustfs_ecstore::api::disk::{DiskOption as EcstoreDiskOption, new_disk as ecstore_new_disk};
-pub(crate) use rustfs_ecstore::api::error::{Error as EcstoreErrorType, StorageError as EcstoreStorageError};
+#[cfg(test)]
+pub(crate) use rustfs_ecstore::api::error::PoolMetadataError as EcstorePoolMetadataError;
+pub(crate) use rustfs_ecstore::api::error::{
+    Error as EcstoreErrorType, PoolMetadataFailure as EcstorePoolMetadataFailure, StorageError as EcstoreStorageError,
+};
 #[cfg(test)]
 pub(crate) use rustfs_ecstore::api::layout::{
     EndpointServerPools as EcstoreEndpointServerPools, Endpoints as EcstoreEndpoints, PoolEndpoints as EcstorePoolEndpoints,
@@ -53,6 +57,9 @@ pub(crate) use rustfs_ecstore::api::storage::{
 use rustfs_storage_api as storage_contracts;
 
 pub(crate) mod owner {
+    #[cfg(test)]
+    pub(crate) use super::EcstorePoolMetadataError;
+    pub(crate) use super::EcstorePoolMetadataFailure;
     pub(crate) use super::storage_contracts::{ObjectIO, ObjectOperations};
 
     pub(crate) use super::{

crates/heal/src/heal/task/heal_bucket.rs

@@ -306,9 +306,7 @@ impl HealTask {
                     let mut progress = self.progress.write().await;
                     progress.update_stage(3, 3);
                 }
-                Err(Error::TaskExecutionFailed {
-                    message: format!("Failed to heal bucket {bucket}: {e}"),
-                })
+                Err(e)
             }
         }
     }
@@ -520,9 +518,7 @@ impl HealTask {
                     error = %err,
                     "Heal cluster pool metadata failed"
                 );
-                Err(Error::TaskExecutionFailed {
-                    message: format!("Failed to heal cluster pool metadata: {err}"),
-                })
+                Err(err)
             }
             Err(Error::TaskCancelled) => Err(Error::TaskCancelled),
             Err(Error::TaskTimeout) => Err(Error::TaskTimeout),
@@ -539,9 +535,7 @@ impl HealTask {
                     error = %err,
                     "Heal cluster pool metadata failed"
                 );
-                Err(Error::TaskExecutionFailed {
-                    message: format!("Failed to heal cluster pool metadata: {err}"),
-                })
+                Err(err)
             }
         }
     }

crates/heal/src/heal/task/tests.rs

@@ -16,6 +16,7 @@ use super::super::{DiskOption, DiskStore, Endpoint, new_disk};
 use super::*;
 use crate::heal::EcstoreError;
 use crate::heal::storage::HealStorageObjectResult;
+use crate::heal::storage_api::owner::{EcstorePoolMetadataError, EcstorePoolMetadataFailure};
 
 mod absent_verdict;
 mod concurrent_delete;
@@ -784,7 +785,10 @@ mod canonical_outcome {
     async fn untraversable_bucket_does_not_claim_complete_cluster_coverage() {
         let storage = Arc::new(MockStorage {
             listed_buckets: Mutex::new(Some(vec!["bucket-a".to_string(), "bucket-b".to_string()])),
-            bucket_heal_errors: Mutex::new(HashMap::from([("bucket-a".to_string(), VecDeque::from(["metadata unavailable"]))])),
+            bucket_heal_errors: Mutex::new(HashMap::from([(
+                "bucket-a".to_string(),
+                VecDeque::from([Error::other("metadata unavailable")]),
+            )])),
             ..Default::default()
         });
         let task = HealTask::from_request(
@@ -1566,7 +1570,7 @@ struct MockStorage {
     include_object_dir_candidate: Mutex<bool>,
     listed_buckets: Mutex<Option<Vec<String>>>,
     bucket_discovery_incomplete: bool,
-    bucket_heal_errors: Mutex<HashMap<String, VecDeque<&'static str>>>,
+    bucket_heal_errors: Mutex<HashMap<String, VecDeque<Error>>>,
     bucket_heal_calls: Mutex<Vec<String>>,
     delete_recovery_results: Mutex<HashMap<String, Result<Option<HealResultItem>>>>,
     delete_recovery_calls: Mutex<Vec<String>>,
@@ -1990,6 +1994,7 @@ fn replacement_identity(
 
 #[derive(Clone)]
 enum MockHealObjectOutcome {
+    PoolMetadata { kind: EcstorePoolMetadataFailure, outer: bool },
     LegacyAmbiguous { outer: bool },
     MissingObject { outer: bool },
     MissingVersion,
@@ -2009,6 +2014,16 @@ enum MockHealObjectOutcome {
     PermanentOther(&'static str),
 }
 
+fn pool_metadata_error(kind: EcstorePoolMetadataFailure) -> Error {
+    Error::Storage(EcstoreError::other(EcstorePoolMetadataError {
+        kind,
+        operation: "bucket heal".to_owned(),
+        phase: "native_heal",
+        since: std::time::UNIX_EPOCH.into(),
+        source: None,
+    }))
+}
+
 fn unavailable_drive_heal_result(state: DriveState) -> (HealResultItem, Option<Error>) {
     (
         HealResultItem {
@@ -2180,6 +2195,14 @@ impl HealStorageAPI for MockStorage {
             .and_then(VecDeque::pop_front)
         {
             return match outcome {
+                MockHealObjectOutcome::PoolMetadata { kind, outer } => {
+                    let error = pool_metadata_error(kind);
+                    if outer {
+                        Err(error)
+                    } else {
+                        Ok((HealResultItem::default(), Some(error)))
+                    }
+                }
                 MockHealObjectOutcome::LegacyAmbiguous { outer } => {
                     let error = Error::Storage(EcstoreError::DeleteRecoveryLegacyAmbiguous);
                     if outer {
@@ -2256,6 +2279,14 @@ impl HealStorageAPI for MockStorage {
         }
         if let Some(outcome) = self.heal_object_outcome.lock().unwrap().take() {
             return match outcome {
+                MockHealObjectOutcome::PoolMetadata { kind, outer } => {
+                    let error = pool_metadata_error(kind);
+                    if outer {
+                        Err(error)
+                    } else {
+                        Ok((HealResultItem::default(), Some(error)))
+                    }
+                }
                 MockHealObjectOutcome::LegacyAmbiguous { outer } => {
                     let error = Error::Storage(EcstoreError::DeleteRecoveryLegacyAmbiguous);
                     if outer {
@@ -2387,14 +2418,14 @@ impl HealStorageAPI for MockStorage {
     async fn heal_bucket(&self, bucket: &str, opts: &HealOpts) -> Result<HealResultItem> {
         self.bucket_heal_calls.lock().unwrap().push(bucket.to_string());
         self.bucket_heal_opts.lock().unwrap().push(*opts);
-        if let Some(message) = self
+        if let Some(error) = self
             .bucket_heal_errors
             .lock()
             .unwrap()
             .get_mut(bucket)
             .and_then(VecDeque::pop_front)
         {
-            return Err(Error::other(message));
+            return Err(error);
         }
         Ok(HealResultItem::default())
     }
@@ -3429,13 +3460,70 @@ async fn cluster_recreate_fails_when_pool_metadata_heal_fails() {
         .await
         .expect_err("cluster recreate heal must not hide pool metadata failure");
 
-    assert!(matches!(err, Error::TaskExecutionFailed { .. }));
+    assert!(matches!(err, Error::Other(ref message) if message == "pool metadata missing"));
     assert_eq!(
         storage.heal_object_calls.lock().expect("object calls").as_slice(),
         ["object-a".to_string(), "object-b".to_string(), POOL_META_NAME.to_string()]
     );
 }
 
+#[tokio::test]
+async fn cluster_pool_metadata_failures_preserve_recovery_classification_in_both_response_shapes() {
+    for outer in [false, true] {
+        for (kind, retryable) in [
+            (EcstorePoolMetadataFailure::ReadUnavailable, true),
+            (EcstorePoolMetadataFailure::TransactionUnknown, true),
+            (EcstorePoolMetadataFailure::RecoveryRequired, false),
+            (EcstorePoolMetadataFailure::FenceLost, false),
+        ] {
+            let storage = Arc::new(MockStorage {
+                listed_buckets: Mutex::new(Some(Vec::new())),
+                ..Default::default()
+            });
+            storage.heal_object_outcomes.lock().expect("object outcomes").insert(
+                POOL_META_NAME.to_string(),
+                VecDeque::from([MockHealObjectOutcome::PoolMetadata { kind, outer }]),
+            );
+            let mut request = HealRequest::new(
+                HealType::Cluster,
+                HealOptions {
+                    recreate_missing: true,
+                    timeout: None,
+                    ..Default::default()
+                },
+                HealPriority::Normal,
+            );
+            request.source = HealRequestSource::Admin;
+            let task = HealTask::from_request(request, storage.clone());
+            let error = task
+                .execute()
+                .await
+                .expect_err("pool metadata failure must reach the scheduler");
+            assert!(
+                matches!(&error, Error::Storage(error) if error.pool_metadata_failure().is_some_and(|failure| failure.kind == kind)),
+                "the original typed pool metadata state must survive either response shape: {error}"
+            );
+            assert_eq!(error.is_recoverable_heal(), retryable, "{kind:?}, outer={outer}");
+            assert_eq!(storage.heal_object_calls.lock().expect("object calls").as_slice(), [POOL_META_NAME]);
+            if retryable {
+                let retry = task
+                    .retry_request_with_remaining_timeout()
+                    .await
+                    .expect("existing retry request");
+                assert_eq!(retry.id, task.id, "recovery retains the accepted task token");
+                HealTask::from_request(retry, storage.clone())
+                    .execute()
+                    .await
+                    .expect("the same task should complete after pool metadata recovery");
+                assert_eq!(
+                    storage.heal_object_calls.lock().expect("object calls").as_slice(),
+                    [POOL_META_NAME, POOL_META_NAME]
+                );
+            }
+        }
+    }
+}
+
 #[tokio::test]
 async fn cluster_dry_run_does_not_heal_pool_metadata() {
     let storage = Arc::new(MockStorage::default());
@@ -3799,7 +3887,10 @@ async fn test_recursive_bucket_heal_reports_typed_exhausted_and_permanent_failur
 async fn test_cluster_heal_continues_after_bucket_failure() {
     let storage = Arc::new(MockStorage {
         listed_buckets: Mutex::new(Some(vec!["bucket-a".to_string(), "bucket-b".to_string()])),
-        bucket_heal_errors: Mutex::new(HashMap::from([("bucket-a".to_string(), VecDeque::from(["metadata unavailable"]))])),
+        bucket_heal_errors: Mutex::new(HashMap::from([(
+            "bucket-a".to_string(),
+            VecDeque::from([Error::other("metadata unavailable")]),
+        )])),
         ..Default::default()
     });
     let request = HealRequest::new(
@@ -3831,7 +3922,10 @@ async fn test_cluster_heal_continues_after_bucket_failure() {
 async fn test_cluster_heal_retries_only_recoverable_bucket() {
     let storage = Arc::new(MockStorage {
         listed_buckets: Mutex::new(Some(vec!["bucket-a".to_string(), "bucket-b".to_string()])),
-        bucket_heal_errors: Mutex::new(HashMap::from([("bucket-a".to_string(), VecDeque::from(["lock acquisition timeout"]))])),
+        bucket_heal_errors: Mutex::new(HashMap::from([(
+            "bucket-a".to_string(),
+            VecDeque::from([Error::other("lock acquisition timeout")]),
+        )])),
         ..Default::default()
     });
     let request = HealRequest::new(
@@ -3855,6 +3949,47 @@ async fn test_cluster_heal_retries_only_recoverable_bucket() {
     );
 }
 
+#[tokio::test(start_paused = true)]
+async fn cluster_bucket_heal_retries_only_recoverable_pool_metadata_failures() {
+    for (kind, retryable) in [
+        (EcstorePoolMetadataFailure::ReadUnavailable, true),
+        (EcstorePoolMetadataFailure::TransactionUnknown, true),
+        (EcstorePoolMetadataFailure::RecoveryRequired, false),
+        (EcstorePoolMetadataFailure::FenceLost, false),
+    ] {
+        let storage = Arc::new(MockStorage {
+            bucket_incarnation_id: Mutex::new(Some(Uuid::new_v4())),
+            bucket_heal_errors: Mutex::new(HashMap::from([("bucket-a".to_owned(), VecDeque::from([pool_metadata_error(kind)]))])),
+            ..Default::default()
+        });
+        let mut request = HealRequest::new(
+            HealType::Cluster,
+            HealOptions {
+                recursive: true,
+                timeout: None,
+                ..Default::default()
+            },
+            HealPriority::Normal,
+        );
+        request.source = HealRequestSource::Admin;
+        let task = HealTask::from_request(request, storage.clone());
+        let result = task.execute().await;
+        if retryable {
+            result.expect("a recoverable pool metadata state must not terminate the root heal");
+            assert_eq!(task.get_status().await, HealTaskStatus::Completed);
+            assert_eq!(
+                storage.bucket_heal_calls.lock().expect("bucket calls").as_slice(),
+                ["bucket-a", "bucket-a"]
+            );
+        } else {
+            result.expect_err("operator recovery and lost fences must remain terminal");
+            let failure = task.take_batch_failure().await.expect("permanent cluster failure");
+            assert_eq!((failure.retryable, failure.permanent), (0, 1));
+            assert_eq!(storage.bucket_heal_calls.lock().expect("bucket calls").as_slice(), ["bucket-a"]);
+        }
+    }
+}
+
 #[tokio::test]
 async fn test_recursive_bucket_heal_does_not_remove_bucket_metadata() {
     let storage = Arc::new(MockStorage::default());
@@ -4617,7 +4752,7 @@ async fn erasure_set_bucket_prepass_failure_stops_before_object_heal() {
     let storage = Arc::new(MockStorage {
         bucket_heal_errors: Mutex::new(HashMap::from([(
             "bucket-a".to_string(),
-            VecDeque::from(["injected bucket prepass failure"]),
+            VecDeque::from([Error::other("injected bucket prepass failure")]),
         )])),
         resume_disk: Mutex::new(Some(disk)),
         ..Default::default()

crates/iam/src/delegation.rs

@@ -0,0 +1,313 @@
+// Copyright 2026 RustFS Team
+// SPDX-License-Identifier: Apache-2.0
+
+//! Durable restrictions owned by an authenticated user. A record is not an IAM
+//! grant or credential; issuing credentials still requires current IAM checks.
+use crate::{error::is_err_config_not_found, store::Store};
+use serde::{Deserialize, Serialize};
+
+const PREFIX: &str = "config/iam/plugin-delegations/v1";
+
+#[derive(Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(deny_unknown_fields)]
+pub struct Restrictions {
+    #[serde(default, skip_serializing_if = "Option::is_none", deserialize_with = "present_value")]
+    pub version: Option<u32>,
+    #[serde(default, skip_serializing_if = "Option::is_none", deserialize_with = "present_value")]
+    pub output_bucket: Option<String>,
+    pub deployment: String,
+    pub bucket: String,
+    pub input_prefix: String,
+    pub output_prefix: String,
+    pub expires_at_unix_seconds: u64,
+}
+
+// An absent v1 field is compatible; an explicitly null v2 field is invalid.
+fn present_value<'de, T: Deserialize<'de>, D: serde::Deserializer<'de>>(deserializer: D) -> Result<Option<T>, D::Error> {
+    T::deserialize(deserializer).map(Some)
+}
+
+impl Restrictions {
+    pub fn output_bucket(&self) -> Result<&str, DelegationError> {
+        match (self.version, self.output_bucket.as_deref()) {
+            (None, None) => Ok(&self.bucket),
+            (Some(2), Some(output)) => Ok(output),
+            _ => Err(DelegationError::Invalid),
+        }
+    }
+
+    pub fn validate(&self, now: u64) -> Result<(), DelegationError> {
+        let output_bucket = self.output_bucket()?;
+        let names: [&str; 5] = [
+            &self.deployment,
+            &self.bucket,
+            &self.input_prefix,
+            &self.output_prefix,
+            output_bucket,
+        ];
+        if names
+            .iter()
+            .any(|s| s.is_empty() || s.len() > 1024 || s.contains("${") || s.chars().any(char::is_control))
+            || self.bucket.contains('/')
+            || self.bucket.contains('*')
+            || self.bucket.contains('?')
+            || output_bucket.contains('/')
+            || output_bucket.contains('*')
+            || output_bucket.contains('?')
+            || self.input_prefix.contains('*')
+            || self.input_prefix.contains('?')
+            || self.output_prefix.contains('*')
+            || self.output_prefix.contains('?')
+            || self.expires_at_unix_seconds <= now
+            || self.expires_at_unix_seconds.saturating_sub(now) > 86400
+        {
+            return Err(DelegationError::Invalid);
+        }
+        Ok(())
+    }
+}
+
+#[derive(Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(deny_unknown_fields)]
+pub struct Delegation {
+    pub version: u32,
+    pub id: String,
+    pub revision: String,
+    pub owner_access_key: String,
+    pub created_at_unix_seconds: u64,
+    pub restrictions: Restrictions,
+}
+
+#[derive(Serialize, Deserialize, PartialEq, Eq)]
+#[serde(deny_unknown_fields)]
+struct Tombstone {
+    version: u32,
+    id: String,
+    revision: String,
+    owner_access_key: String,
+}
+
+#[derive(Debug, thiserror::Error)]
+pub enum DelegationError {
+    #[error("invalid delegation restriction")]
+    Invalid,
+    #[error("delegation not found")]
+    NotFound,
+    #[error("delegation owner rejected")]
+    OwnerRejected,
+    #[error("delegation unavailable")]
+    Unavailable,
+    #[error("delegation revoked")]
+    Revoked,
+    #[error("delegation expired")]
+    Expired,
+}
+
+fn record_path(id: &str) -> Result<String, DelegationError> {
+    if id.len() != 32 || !id.bytes().all(|c| c.is_ascii_hexdigit()) {
+        return Err(DelegationError::Invalid);
+    }
+    Ok(format!("{PREFIX}/{id}/record.json"))
+}
+
+async fn load<T: Store>(store: &T, id: &str) -> Result<Delegation, DelegationError> {
+    let record: Delegation = store.load_iam_config_strict(record_path(id)?).await.map_err(|error| {
+        if is_err_config_not_found(&error) {
+            DelegationError::NotFound
+        } else {
+            DelegationError::Unavailable
+        }
+    })?;
+    if !matches!(record.version, 1 | 2)
+        || record.version != record.restrictions.version.unwrap_or(1)
+        || record.id != id
+        || record.revision != id
+        || record.owner_access_key.is_empty()
+    {
+        return Err(DelegationError::Unavailable);
+    }
+    record
+        .restrictions
+        .validate(record.created_at_unix_seconds)
+        .map_err(|_| DelegationError::Unavailable)?;
+    Ok(record)
+}
+
+pub(crate) async fn create<T: Store>(
+    store: &T,
+    owner: &str,
+    restrictions: Restrictions,
+    now: u64,
+) -> Result<Delegation, DelegationError> {
+    restrictions.validate(now)?;
+    if owner.is_empty() {
+        return Err(DelegationError::OwnerRejected);
+    }
+    // IDs are generated exclusively here; no update operation accepts an ID.
+    let id = format!("{:032x}", rand::random::<u128>());
+    let path = record_path(&id)?;
+    match store.load_iam_config_strict::<Delegation>(&path).await {
+        Err(error) if is_err_config_not_found(&error) => {}
+        _ => return Err(DelegationError::Unavailable),
+    }
+    let record = Delegation {
+        version: restrictions.version.unwrap_or(1),
+        revision: id.clone(),
+        id,
+        owner_access_key: owner.to_owned(),
+        created_at_unix_seconds: now,
+        restrictions,
+    };
+    store
+        .save_iam_config(&record, path)
+        .await
+        .map_err(|_| DelegationError::Unavailable)?;
+    if load(store, &record.id).await? != record {
+        return Err(DelegationError::Unavailable);
+    }
+    Ok(record)
+}
+
+pub(crate) async fn revoke<T: Store>(store: &T, owner: &str, id: &str) -> Result<(), DelegationError> {
+    let record = load(store, id).await?;
+    if record.owner_access_key != owner {
+        return Err(DelegationError::OwnerRejected);
+    }
+    let tombstone = Tombstone {
+        version: 1,
+        id: record.id,
+        revision: record.revision,
+        owner_access_key: record.owner_access_key,
+    };
+    let path = format!("{PREFIX}/{id}/revoked.json");
+    // Every retry writes exactly the same revocation; active records never change.
+    store
+        .save_iam_config(&tombstone, &path)
+        .await
+        .map_err(|_| DelegationError::Unavailable)?;
+    let saved: Tombstone = store
+        .load_iam_config_strict(path)
+        .await
+        .map_err(|_| DelegationError::Unavailable)?;
+    if saved != tombstone {
+        return Err(DelegationError::Unavailable);
+    }
+    Ok(())
+}
+
+pub(crate) async fn read_active<T: Store>(store: &T, owner: &str, id: &str, now: u64) -> Result<Delegation, DelegationError> {
+    let record = load(store, id).await?;
+    if record.owner_access_key != owner {
+        return Err(DelegationError::OwnerRejected);
+    }
+    check_active(store, record, now).await
+}
+
+pub(crate) async fn read_owned<T: Store>(store: &T, owner: &str, id: &str) -> Result<Delegation, DelegationError> {
+    let record = load(store, id).await?;
+    if record.owner_access_key != owner {
+        return Err(DelegationError::OwnerRejected);
+    }
+    Ok(record)
+}
+
+pub(crate) async fn read_active_for_broker<T: Store>(store: &T, id: &str, now: u64) -> Result<Delegation, DelegationError> {
+    let record = load(store, id).await?;
+    check_active(store, record, now).await
+}
+async fn check_active<T: Store>(store: &T, record: Delegation, now: u64) -> Result<Delegation, DelegationError> {
+    let id = &record.id;
+    match store
+        .load_iam_config_strict::<Tombstone>(format!("{PREFIX}/{id}/revoked.json"))
+        .await
+    {
+        Ok(_) => return Err(DelegationError::Revoked),
+        Err(error) if is_err_config_not_found(&error) => {}
+        Err(_) => return Err(DelegationError::Unavailable),
+    }
+    if now >= record.restrictions.expires_at_unix_seconds {
+        return Err(DelegationError::Expired);
+    }
+    Ok(record)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn delegation_v1_json_remains_compatible() {
+        let legacy = serde_json::json!({"deployment":"runner-a","bucket":"photos",
+            "input_prefix":"inputs/","output_prefix":"outputs/","expires_at_unix_seconds":200});
+        let restriction: Restrictions = serde_json::from_value(legacy.clone()).expect("legacy restriction");
+        restriction.validate(100).expect("legacy validation");
+        assert_eq!(restriction.output_bucket().expect("v1 output"), "photos");
+        assert_eq!(serde_json::to_value(restriction).expect("legacy serialization"), legacy);
+        let record = serde_json::json!({"version":1,"id":"a".repeat(32),"revision":"a".repeat(32),
+            "owner_access_key":"owner","created_at_unix_seconds":100,"restrictions":legacy});
+        let decoded: Delegation = serde_json::from_value(record.clone()).expect("legacy record");
+        assert_eq!(serde_json::to_value(decoded).expect("legacy record serialization"), record);
+    }
+
+    #[test]
+    fn delegation_v2_requires_explicit_output_bucket() {
+        let valid = serde_json::json!({"version":2,"deployment":"runner-a","bucket":"photos",
+            "input_prefix":"inputs/","output_bucket":"artifacts","output_prefix":"outputs/",
+            "expires_at_unix_seconds":200});
+        let restriction: Restrictions = serde_json::from_value(valid.clone()).expect("v2 restriction");
+        restriction.validate(100).expect("explicit output bucket");
+        assert_eq!(restriction.output_bucket().expect("v2 output"), "artifacts");
+        assert_eq!(serde_json::to_value(restriction).expect("v2 serialization"), valid);
+        for key in ["version", "output_bucket"] {
+            let mut bad = valid.clone();
+            bad.as_object_mut().expect("object").remove(key);
+            assert!(
+                serde_json::from_value::<Restrictions>(bad).map_or(true, |r| r.validate(100).is_err()),
+                "v2 required {key}"
+            );
+        }
+        for (key, value) in [
+            ("version", serde_json::json!(1)),
+            ("version", serde_json::json!(3)),
+            ("version", serde_json::Value::Null),
+            ("output_bucket", serde_json::Value::Null),
+            ("output_bucket", serde_json::json!("")),
+            ("output_bucket", serde_json::json!("other/*")),
+            ("output_bucket", serde_json::json!("${aws:username}")),
+            ("output_bucket", serde_json::json!("other?")),
+            ("output_bucket", serde_json::json!("other\n")),
+            ("unknown", serde_json::json!(true)),
+        ] {
+            let mut bad = valid.clone();
+            bad[key] = value;
+            assert!(
+                serde_json::from_value::<Restrictions>(bad).map_or(true, |r| r.validate(100).is_err()),
+                "invalid v2 {key}"
+            );
+        }
+    }
+
+    #[test]
+    fn restrictions_are_literal_bounded_and_expiring() {
+        let mut restriction = Restrictions {
+            version: None,
+            output_bucket: None,
+            deployment: "runner-a".into(),
+            bucket: "photos".into(),
+            input_prefix: "inputs/".into(),
+            output_prefix: "outputs/".into(),
+            expires_at_unix_seconds: 200,
+        };
+        assert!(restriction.validate(100).is_ok());
+        restriction.output_prefix = "outputs/*".into();
+        assert!(matches!(restriction.validate(100), Err(DelegationError::Invalid)));
+        restriction.output_prefix = "outputs/".into();
+        assert!(matches!(restriction.validate(200), Err(DelegationError::Invalid)));
+        restriction.expires_at_unix_seconds = 200;
+        restriction.input_prefix = "inputs/${aws:username}/".into();
+        assert!(
+            matches!(restriction.validate(100), Err(DelegationError::Invalid)),
+            "C07_LITERAL_SCOPE_BOUND: policy variables are not literal restrictions"
+        );
+        assert!(record_path("../../users").is_err());
+    }
+}

crates/iam/src/lib.rs

@@ -28,6 +28,7 @@ pub(crate) const EVENT_OIDC_DIAGNOSTICS: &str = "oidc_diagnostics";
 const EVENT_OIDC_STATE: &str = "oidc_state";
 
 pub mod cache;
+pub mod delegation;
 pub mod error;
 pub mod federation;
 pub mod keyring;

crates/iam/src/storage_api.rs

@@ -91,6 +91,7 @@ pub(crate) mod crate_boundary {
 
 pub(crate) mod object_store {
     pub(crate) use super::storage_contracts::{HTTPPreconditions, ListOperations, ObjectInfoOrErr, ObjectOperations};
+    pub(crate) use rustfs_ecstore::api::config::com::read_config_preserve_empty_with_metadata_opts;
 }
 
 pub(crate) mod runtime {

crates/iam/src/store.rs

@@ -26,6 +26,11 @@ pub trait Store: Clone + Send + Sync + 'static {
     fn has_watcher(&self) -> bool;
     async fn save_iam_config<Item: Serialize + Send>(&self, item: Item, path: impl AsRef<str> + Send) -> Result<()>;
     async fn load_iam_config<Item: DeserializeOwned>(&self, path: impl AsRef<str> + Send) -> Result<Item>;
+    /// Only confirmed storage absence may return ConfigNotFound. Corrupt or
+    /// undecryptable objects must remain errors, especially for revocations.
+    async fn load_iam_config_strict<Item: DeserializeOwned>(&self, _path: impl AsRef<str> + Send) -> Result<Item> {
+        Err(crate::error::Error::IamSysNotInitialized)
+    }
     async fn delete_iam_config(&self, path: impl AsRef<str> + Send) -> Result<()>;
 
     async fn save_user_identity(&self, name: &str, user_type: UserType, item: UserIdentity, ttl: Option<usize>) -> Result<()>;

crates/iam/src/store/object.rs

@@ -42,6 +42,7 @@ use tracing::{debug, error, warn};
 
 use crate::storage_api::object_store::{
     HTTPPreconditions, ListOperations, ObjectInfoOrErr as StorageObjectInfoOrErr, ObjectOperations,
+    read_config_preserve_empty_with_metadata_opts,
 };
 
 pub static IAM_CONFIG_PREFIX: LazyLock<String> = LazyLock::new(|| format!("{IAM_CONFIG_ROOT_PREFIX}/iam"));
@@ -611,6 +612,11 @@ impl ObjectStore {
         Ok(serde_json::from_slice(&outcome.plain)?)
     }
 
+    fn decode_iam_config_strict<Item: DeserializeOwned>(data: &[u8]) -> Result<Item> {
+        let outcome = Self::decrypt_data_with_source(data)?;
+        Ok(serde_json::from_slice(&outcome.plain)?)
+    }
+
     /// Parameterized core of [`Store::load_user_identity`].
     async fn load_user_identity_with(&self, name: &str, user_type: UserType, mode: LoadMode) -> Result<UserIdentity> {
         let mut u: UserIdentity = self
@@ -824,6 +830,12 @@ impl Store for ObjectStore {
     async fn load_iam_config<Item: DeserializeOwned>(&self, path: impl AsRef<str> + Send) -> Result<Item> {
         self.load_iam_config_with(path, LoadMode::Locked).await
     }
+    async fn load_iam_config_strict<Item: DeserializeOwned>(&self, path: impl AsRef<str> + Send) -> Result<Item> {
+        let (data, _) =
+            read_config_preserve_empty_with_metadata_opts(self.object_api.clone(), path.as_ref(), &LoadMode::Locked.read_opts())
+                .await?;
+        Self::decode_iam_config_strict(&data)
+    }
     /// Saves IAM configuration with a retry mechanism on failure.
     ///
     /// Attempts to save the IAM configuration up to 5 times if the storage layer is not ready,
@@ -1458,6 +1470,40 @@ mod tests {
         assert!(result.is_err(), "corrupt stream_io data should fail decrypt");
     }
 
+    #[test]
+    fn strict_revocation_load_keeps_real_crypto_failure_distinct_from_absence() {
+        let cred = test_cred();
+        let key = format!("{}:{}", cred.access_key, cred.secret_key);
+        let plain = br#"{"version":1,"id":"revoked"}"#;
+        let mut encrypted = rustfs_crypto::encrypt_stream_io(key.as_bytes(), plain).expect("real stored ciphertext");
+        // Exercise the exact decoder used after the actual object read.
+        assert!(ObjectStore::decode_iam_config_strict::<serde_json::Value>(&encrypted).is_ok());
+        encrypted[50] ^= 0xFF;
+        let error = ObjectStore::decode_iam_config_strict::<serde_json::Value>(&encrypted)
+            .expect_err("corrupt tombstone must not become missing");
+        assert!(
+            matches!(error, Error::CryptoError(_)),
+            "C07_REVOCATION_FAIL_CLOSED: preserve actual crypto error"
+        );
+        assert!(
+            !crate::error::is_err_config_not_found(&error),
+            "C07_REVOCATION_FAIL_CLOSED: corrupted revocation is not absence"
+        );
+        // The preserve-empty reader keeps an existing zero-byte object as
+        // Ok(empty); ecstore's read_config_preserve_empty_distinguishes_empty_object
+        // covers that storage boundary. Its payload must fail here, not become
+        // ConfigNotFound and reactivate a revoked delegation.
+        let empty =
+            ObjectStore::decode_iam_config_strict::<serde_json::Value>(&[]).expect_err("an existing empty tombstone is corrupt");
+        assert!(
+            !crate::error::is_err_config_not_found(&empty),
+            "C07_REVOCATION_FAIL_CLOSED: empty existing revocation is not absence"
+        );
+        let invalid_json =
+            ObjectStore::decode_iam_config_strict::<serde_json::Value>(br#"{"version": }"#).expect_err("invalid stored JSON");
+        assert!(!crate::error::is_err_config_not_found(&invalid_json));
+    }
+
     #[test]
     fn test_decrypt_data_short_data_fails() {
         let short = &[0x00u8; 40]; // less than 41-byte stream_io header, not valid JSON

crates/iam/src/sys.rs

@@ -75,6 +75,7 @@ pub const STATUS_ENABLED: &str = "enabled";
 pub const STATUS_DISABLED: &str = "disabled";
 
 pub const POLICYNAME: &str = "policy";
+pub const PLUGIN_ATTEMPT_CREDENTIAL_CLAIM: &str = "rustfs:plugin-attempt-v1";
 pub const SESSION_POLICY_NAME: &str = "sessionPolicy";
 pub const SESSION_POLICY_NAME_EXTRACTED: &str = "sessionPolicy-extracted";
 const VERIFIED_FEDERATED_POLICY_CLAIM: &str = "x-rustfs-internal-federated-policy";
@@ -168,6 +169,12 @@ enum PreparedServicePolicyMode {
 
 #[derive(Clone)]
 enum PreparedIamMode {
+    TerminalDeny,
+    PluginAttemptSts {
+        is_owner: bool,
+        combined_policy: Policy,
+        session_policy: PreparedSessionPolicy,
+    },
     Opa,
     Owner,
     Deny,
@@ -202,7 +209,7 @@ impl PreparedIamAuth {
     pub async fn needs_existing_object_tag_for_args(&self, args: &Args<'_>) -> bool {
         match &self.mode {
             PreparedIamMode::Opa => true,
-            PreparedIamMode::Owner | PreparedIamMode::Deny => false,
+            PreparedIamMode::Owner | PreparedIamMode::Deny | PreparedIamMode::TerminalDeny => false,
             PreparedIamMode::Regular { combined_policy } => {
                 policy_needs_existing_object_tag_for_args(combined_policy, args).await
             }
@@ -210,6 +217,11 @@ impl PreparedIamAuth {
                 combined_policy,
                 session_policy,
                 ..
+            }
+            | PreparedIamMode::PluginAttemptSts {
+                combined_policy,
+                session_policy,
+                ..
             } => {
                 policy_needs_existing_object_tag_for_args(combined_policy, args).await
                     || prepared_session_policy_needs_existing_object_tag_for_args(session_policy, args).await
@@ -239,14 +251,56 @@ impl PreparedIamAuth {
     pub fn combined_policy_for_view(&self) -> Option<&Policy> {
         match &self.mode {
             PreparedIamMode::Regular { combined_policy } => Some(combined_policy),
-            PreparedIamMode::Sts { combined_policy, .. } => Some(combined_policy),
+            PreparedIamMode::Sts { combined_policy, .. } | PreparedIamMode::PluginAttemptSts { combined_policy, .. } => {
+                Some(combined_policy)
+            }
             PreparedIamMode::ServiceAccount { combined_policy, .. } => Some(combined_policy),
-            PreparedIamMode::Opa | PreparedIamMode::Owner | PreparedIamMode::Deny => None,
+            PreparedIamMode::Opa | PreparedIamMode::Owner | PreparedIamMode::Deny | PreparedIamMode::TerminalDeny => None,
         }
     }
 }
 
 impl<T: Store> IamSys<T> {
+    /// For the authenticated, explicitly configured broker handler only.
+    pub async fn read_active_plugin_delegation_for_broker(
+        &self,
+        id: &str,
+        now: u64,
+    ) -> std::result::Result<crate::delegation::Delegation, crate::delegation::DelegationError> {
+        crate::delegation::read_active_for_broker(&self.store.api, id, now).await
+    }
+    pub async fn create_plugin_delegation(
+        &self,
+        owner: &str,
+        restrictions: crate::delegation::Restrictions,
+        now: u64,
+    ) -> std::result::Result<crate::delegation::Delegation, crate::delegation::DelegationError> {
+        crate::delegation::create(&self.store.api, owner, restrictions, now).await
+    }
+    pub async fn revoke_plugin_delegation(
+        &self,
+        owner: &str,
+        id: &str,
+    ) -> std::result::Result<(), crate::delegation::DelegationError> {
+        crate::delegation::revoke(&self.store.api, owner, id).await
+    }
+    pub async fn read_active_plugin_delegation(
+        &self,
+        owner: &str,
+        id: &str,
+        now: u64,
+    ) -> std::result::Result<crate::delegation::Delegation, crate::delegation::DelegationError> {
+        crate::delegation::read_active(&self.store.api, owner, id, now).await
+    }
+    /// Reads an owned delegation record for historical lookups, including expired or revoked records.
+    pub async fn read_owned_plugin_delegation(
+        &self,
+        owner: &str,
+        id: &str,
+    ) -> std::result::Result<crate::delegation::Delegation, crate::delegation::DelegationError> {
+        crate::delegation::read_owned(&self.store.api, owner, id).await
+    }
+
     /// Create a new IamSys instance with the given IamCache store
     ///
     /// # Arguments
@@ -281,6 +335,16 @@ impl<T: Store> IamSys<T> {
         *guard = PolicyPluginState::Ready(client);
     }
 
+    /// Restricted credentials require the built-in parent/session intersection.
+    /// External authorization bypasses that path, so only Disabled is supported.
+    pub async fn ensure_restricted_credential_vending() -> Result<()> {
+        if matches!(Self::policy_plugin_state().await, PolicyPluginState::Disabled) {
+            Ok(())
+        } else {
+            Err(Error::IAMActionNotAllowed)
+        }
+    }
+
     pub async fn get_policy_plugin_client() -> Option<rustfs_policy::policy::opa::AuthZPlugin> {
         let policy_plugin_state = get_policy_plugin_state();
         let guard = policy_plugin_state.read().await;
@@ -1383,17 +1447,50 @@ impl<T: Store> IamSys<T> {
     /// 1) know whether policy evaluation may need `s3:ExistingObjectTag`, and
     /// 2) evaluate with final conditions without re-merging identity policies.
     pub async fn prepare_auth(&self, args: &Args<'_>) -> PreparedIamAuth {
-        if args.is_owner {
+        let marked = args.claims.contains_key(PLUGIN_ATTEMPT_CREDENTIAL_CLAIM);
+        if args.is_owner && !marked {
             return PreparedIamAuth {
                 needs_existing_object_tag: false,
                 mode: PreparedIamMode::Owner,
             };
         }
-
-        if let Some(prepared) = Self::policy_plugin_state().await.prepared_iam_auth() {
+        // One observed state decides this request's path. Marked credentials
+        // never enter OPA, including after a restart or on another node.
+        let state = Self::policy_plugin_state().await;
+        if marked {
+            if args.is_owner
+                || args.claims.get(PLUGIN_ATTEMPT_CREDENTIAL_CLAIM) != Some(&Value::Bool(true))
+                || !matches!(state, PolicyPluginState::Disabled)
+            {
+                return PreparedIamAuth {
+                    needs_existing_object_tag: false,
+                    mode: PreparedIamMode::TerminalDeny,
+                };
+            }
+            let prepared = self.prepare_builtin_auth(args).await;
+            let mode = match prepared.mode {
+                PreparedIamMode::Sts {
+                    is_owner,
+                    combined_policy,
+                    session_policy,
+                } => PreparedIamMode::PluginAttemptSts {
+                    is_owner,
+                    combined_policy,
+                    session_policy,
+                },
+                _ => PreparedIamMode::TerminalDeny,
+            };
+            return PreparedIamAuth {
+                needs_existing_object_tag: prepared.needs_existing_object_tag,
+                mode,
+            };
+        }
+        if let Some(prepared) = state.prepared_iam_auth() {
             return prepared;
         }
-
+        self.prepare_builtin_auth(args).await
+    }
+    async fn prepare_builtin_auth(&self, args: &Args<'_>) -> PreparedIamAuth {
         let Ok((is_svc, parent_user)) = self.is_service_account(args.account).await else {
             return PreparedIamAuth {
                 needs_existing_object_tag: false,
@@ -1425,6 +1522,20 @@ impl<T: Store> IamSys<T> {
     /// bucket policies on an IAM denial. An error must not become an implicit deny.
     pub async fn try_eval_prepared(&self, prepared: &PreparedIamAuth, args: &Args<'_>) -> Result<bool> {
         Ok(match &prepared.mode {
+            PreparedIamMode::TerminalDeny => return Err(Error::IAMActionNotAllowed),
+            PreparedIamMode::PluginAttemptSts {
+                is_owner,
+                combined_policy,
+                session_policy,
+            } => {
+                // A false IAM result permits bucket-policy fallback. Restricted
+                // plugin credentials must instead terminate authorization.
+                let session_allowed = evaluate_prepared_session_policy(session_policy, args).await == Some(true);
+                if !session_allowed || !(*is_owner || combined_policy.is_allowed(args).await) {
+                    return Err(Error::IAMActionNotAllowed);
+                }
+                true
+            }
             PreparedIamMode::Opa => {
                 let Some(opa_enable) = Self::get_policy_plugin_client().await else {
                     tracing::warn!("eval_prepared: OPA mode requested but plugin is unavailable");
@@ -2127,6 +2238,145 @@ mod tests {
         assert!(prepared.combined_policy_for_view().is_none());
     }
 
+    #[tokio::test]
+    #[serial]
+    async fn marked_signed_sts_denial_is_terminal_before_public_bucket_fallback() {
+        let iam = IamSys::new(IamCache::new(StsTestMockStore::new(false)).await.unwrap());
+        let previous = IamSys::<StsTestMockStore>::policy_plugin_state().await;
+        let signing_key = "c07-test-token-signing-key";
+        let mut metadata=HashMap::from([
+            ("parent".into(),Value::String("sts-fallback-test-parent".into())),
+            ("exp".into(),serde_json::json!((OffsetDateTime::now_utc()+time::Duration::hours(1)).unix_timestamp())),
+            (SESSION_POLICY_NAME.into(),Value::String(base64_simd::URL_SAFE_NO_PAD.encode_to_string(br#"{"Version":"2012-10-17","Statement":[{"Effect":"Allow","Action":["s3:GetObject"],"Resource":["arn:aws:s3:::mybucket/inside"]}]}"#))),
+        ]);
+        metadata.insert(PLUGIN_ATTEMPT_CREDENTIAL_CLAIM.into(), Value::Bool(true));
+        let mut marked = get_new_credentials_with_metadata(&metadata, signing_key).unwrap();
+        marked.parent_user = "sts-fallback-test-parent".into();
+        let marked_claims: HashMap<String, Value> = rustfs_policy::utils::extract_claims(&marked.session_token, signing_key)
+            .expect("signed test credentials must decode")
+            .claims;
+        let marked_user = UserIdentity::from(marked.clone());
+        iam.store
+            .cache
+            .add_or_update_sts_account(&marked.access_key, &marked_user, OffsetDateTime::now_utc());
+        metadata.remove(PLUGIN_ATTEMPT_CREDENTIAL_CLAIM);
+        let mut ordinary = get_new_credentials_with_metadata(&metadata, signing_key).unwrap();
+        ordinary.parent_user = marked.parent_user.clone();
+        let ordinary_claims: HashMap<String, Value> = rustfs_policy::utils::extract_claims(&ordinary.session_token, signing_key)
+            .expect("signed test credentials must decode")
+            .claims;
+        iam.store.cache.add_or_update_sts_account(
+            &ordinary.access_key,
+            &UserIdentity::from(ordinary.clone()),
+            OffsetDateTime::now_utc(),
+        );
+        let groups = None;
+        let conditions = HashMap::new();
+        let args = Args {
+            account: &marked.access_key,
+            groups: &groups,
+            action: Action::S3Action(S3Action::GetObjectAction),
+            bucket: "mybucket",
+            object: "outside",
+            conditions: &conditions,
+            is_owner: false,
+            claims: &marked_claims,
+            deny_only: false,
+        };
+        *get_policy_plugin_state().write().await = PolicyPluginState::Disabled;
+        let denied = iam.prepare_auth(&args).await;
+        let disabled_terminal = matches!(iam.try_eval_prepared(&denied, &args).await, Err(Error::IAMActionNotAllowed));
+        let inside = Args {
+            object: "inside",
+            ..args.clone()
+        };
+        let allowed = iam.prepare_auth(&inside).await;
+        let inside_allowed = matches!(iam.try_eval_prepared(&allowed, &inside).await, Ok(true));
+        let unmarked_args = Args {
+            account: &ordinary.access_key,
+            claims: &ordinary_claims,
+            ..args.clone()
+        };
+        let unmarked = iam.prepare_auth(&unmarked_args).await;
+        let ordinary_false = matches!(iam.try_eval_prepared(&unmarked, &unmarked_args).await, Ok(false));
+        let public:rustfs_policy::policy::BucketPolicy=serde_json::from_value(serde_json::json!({"Version":"2012-10-17","Statement":[{"Effect":"Allow","Principal":{"AWS":["*"]},"Action":["s3:GetObject"],"Resource":["arn:aws:s3:::mybucket/*"]}]})).unwrap();
+        let public_allows = public
+            .is_allowed(&rustfs_policy::policy::BucketPolicyArgs {
+                account: &marked.access_key,
+                groups: &groups,
+                action: args.action,
+                bucket: args.bucket,
+                object: args.object,
+                conditions: &conditions,
+                is_owner: false,
+            })
+            .await;
+        IamSys::<StsTestMockStore>::set_policy_plugin_client(opa::AuthZPlugin::new(opa::Args {
+            url: "http://127.0.0.1:8181/allow".into(),
+            auth_token: String::new(),
+        }))
+        .await;
+        let opa_marked = iam.prepare_auth(&args).await;
+        let ready_terminal = matches!(iam.try_eval_prepared(&opa_marked, &args).await, Err(Error::IAMActionNotAllowed));
+        let opa_ordinary = iam.prepare_auth(&unmarked_args).await;
+        let ordinary_keeps_opa = matches!(opa_ordinary.mode, PreparedIamMode::Opa);
+        // The captured Disabled preparation stays on built-in intersection even
+        // if an external policy client becomes ready before evaluation.
+        let captured_still_terminal = matches!(iam.try_eval_prepared(&denied, &args).await, Err(Error::IAMActionNotAllowed));
+        *get_policy_plugin_state().write().await = PolicyPluginState::Initializing;
+        let pending = iam.prepare_auth(&args).await;
+        let initializing_terminal = matches!(iam.try_eval_prepared(&pending, &args).await, Err(Error::IAMActionNotAllowed));
+        *get_policy_plugin_state().write().await = PolicyPluginState::Failed;
+        let failed = iam.prepare_auth(&args).await;
+        let failed_terminal = matches!(iam.try_eval_prepared(&failed, &args).await, Err(Error::IAMActionNotAllowed));
+        *get_policy_plugin_state().write().await = previous;
+        assert!(public_allows, "C07_PUBLIC_BUCKET_CONTROL: real public policy permits outside object");
+        assert!(
+            disabled_terminal && captured_still_terminal,
+            "C07_SCOPE_TERMINAL_BOUND: bucket policy must not rescue restricted scope denial"
+        );
+        assert!(
+            ready_terminal && initializing_terminal && failed_terminal,
+            "C07_EXTERNAL_POLICY_BOUND: marked persisted STS cannot enter OPA"
+        );
+        assert!(
+            inside_allowed && ordinary_false && ordinary_keeps_opa,
+            "C07_UNMARKED_COMPAT: preserve ordinary STS and valid marked scope"
+        );
+    }
+
+    #[tokio::test]
+    #[serial]
+    async fn restricted_vending_rejects_actual_external_policy_plugin_state() {
+        let previous = IamSys::<StsTestMockStore>::policy_plugin_state().await;
+        IamSys::<StsTestMockStore>::set_policy_plugin_client(opa::AuthZPlugin::new(opa::Args {
+            url: "http://127.0.0.1:8181/v1/data/rustfs/authz/allow".into(),
+            auth_token: String::new(),
+        }))
+        .await;
+        let active_rejected = IamSys::<StsTestMockStore>::ensure_restricted_credential_vending()
+            .await
+            .is_err();
+        *get_policy_plugin_state().write().await = PolicyPluginState::Initializing;
+        let initializing_rejected = IamSys::<StsTestMockStore>::ensure_restricted_credential_vending()
+            .await
+            .is_err();
+        *get_policy_plugin_state().write().await = PolicyPluginState::Failed;
+        let failed_rejected = IamSys::<StsTestMockStore>::ensure_restricted_credential_vending()
+            .await
+            .is_err();
+        *get_policy_plugin_state().write().await = PolicyPluginState::Disabled;
+        let disabled_allowed = IamSys::<StsTestMockStore>::ensure_restricted_credential_vending()
+            .await
+            .is_ok();
+        *get_policy_plugin_state().write().await = previous;
+        assert!(
+            active_rejected && initializing_rejected && failed_rejected,
+            "C07_EXTERNAL_POLICY_BOUND: external authorization cannot bypass minted session scope"
+        );
+        assert!(disabled_allowed);
+    }
+
     #[tokio::test]
     #[serial]
     async fn test_prepare_auth_requests_existing_object_tags_in_opa_mode() {

crates/policy/src/policy/action.rs

@@ -568,6 +568,24 @@ pub enum AdminAction {
     GetTableLifecycleAction,
     #[strum(serialize = "admin:SetTableLifecycle")]
     SetTableLifecycleAction,
+    #[strum(serialize = "admin:CreatePluginDelegation")]
+    CreatePluginDelegationAction,
+    #[strum(serialize = "admin:IssuePluginAttempt")]
+    IssuePluginAttemptAction,
+    #[strum(serialize = "admin:SubmitPluginJob")]
+    SubmitPluginJobAction,
+    #[strum(serialize = "admin:GetPluginRun")]
+    GetPluginRunAction,
+    #[strum(serialize = "admin:CancelPluginRun")]
+    CancelPluginRunAction,
+    #[strum(serialize = "admin:ListPluginRuns")]
+    ListPluginRunsAction,
+    #[strum(serialize = "admin:ReplayPluginRun")]
+    ReplayPluginRunAction,
+    #[strum(serialize = "admin:GetPluginDelegation")]
+    GetPluginDelegationAction,
+    #[strum(serialize = "admin:RevokePluginDelegation")]
+    RevokePluginDelegationAction,
     #[strum(serialize = "admin:GetTableCredentials")]
     GetTableCredentialsAction,
     #[strum(serialize = "admin:RunTableMaintenance")]
@@ -713,6 +731,15 @@ impl AdminAction {
                 | AdminAction::GetTableLifecycleAction
                 | AdminAction::SetTableLifecycleAction
                 | AdminAction::GetTableCredentialsAction
+                | AdminAction::IssuePluginAttemptAction
+                | AdminAction::SubmitPluginJobAction
+                | AdminAction::GetPluginRunAction
+                | AdminAction::CancelPluginRunAction
+                | AdminAction::ListPluginRunsAction
+                | AdminAction::ReplayPluginRunAction
+                | AdminAction::GetPluginDelegationAction
+                | AdminAction::CreatePluginDelegationAction
+                | AdminAction::RevokePluginDelegationAction
                 | AdminAction::RunTableMaintenanceAction
                 | AdminAction::GetTableMetadataLocationAction
                 | AdminAction::SetTableMetadataLocationAction
@@ -913,6 +940,35 @@ mod tests {
         assert_eq!(arr[0].as_str().unwrap(), "s3:*");
     }
 
+    #[test]
+    fn plugin_delegation_actions_are_explicit_and_unscoped() {
+        for (name, expected) in [
+            ("admin:GetPluginDelegation", AdminAction::GetPluginDelegationAction),
+            ("admin:CreatePluginDelegation", AdminAction::CreatePluginDelegationAction),
+            ("admin:RevokePluginDelegation", AdminAction::RevokePluginDelegationAction),
+            ("admin:SubmitPluginJob", AdminAction::SubmitPluginJobAction),
+            ("admin:GetPluginRun", AdminAction::GetPluginRunAction),
+            ("admin:CancelPluginRun", AdminAction::CancelPluginRunAction),
+            ("admin:ListPluginRuns", AdminAction::ListPluginRunsAction),
+            ("admin:ReplayPluginRun", AdminAction::ReplayPluginRunAction),
+        ] {
+            assert_eq!(AdminAction::try_from(name).unwrap(), expected);
+            assert!(expected.is_valid());
+            assert!(!expected.is_table_resource_scoped());
+        }
+        assert_eq!(
+            AdminAction::try_from("admin:IssuePluginAttempt").unwrap(),
+            AdminAction::IssuePluginAttemptAction
+        );
+        assert!(AdminAction::IssuePluginAttemptAction.is_valid());
+        assert!(AdminAction::SubmitPluginJobAction.is_valid());
+        assert!(AdminAction::GetPluginRunAction.is_valid());
+        assert!(AdminAction::CancelPluginRunAction.is_valid());
+        assert!(AdminAction::ListPluginRunsAction.is_valid());
+        assert!(AdminAction::ReplayPluginRunAction.is_valid());
+        assert!(AdminAction::try_from("admin:IssuePluginCredentials").is_err());
+    }
+
     #[test]
     fn test_get_replication_metrics_admin_action_is_valid() {
         assert!(AdminAction::GetReplicationMetricsAction.is_valid());

crates/scanner/src/error.rs

@@ -53,6 +53,10 @@ pub enum ScannerError {
     #[error("Remote namespace scanner disk is already active")]
     RemoteDiskBusy,
 
+    /// Node resource pressure deferred work before its first storage poll.
+    #[error("Scanner node resource admission deferred")]
+    ResourceDeferred,
+
     /// Partial data usage cache produced before the scanner stopped.
     #[error("Scanner stopped with partial data usage cache")]
     PartialCache(Box<DataUsageCache>),

crates/scanner/src/lib.rs

@@ -50,9 +50,9 @@ use storage_api::owner::{
 };
 #[cfg(test)]
 use storage_api::owner::{
-    EcstoreDiskOption, EcstoreDiskStore, EcstoreEndpoint, EcstoreEndpointServerPools, EcstoreEndpoints, EcstoreInstanceContext,
-    EcstorePoolEndpoints, ecstore_config_init, ecstore_init_bucket_metadata_sys, ecstore_init_local_disks_with_instance_ctx,
-    ecstore_new_disk,
+    EcstoreDiskOption, EcstoreDiskStore, EcstoreEndpoint, EcstoreEndpointServerPools, EcstoreEndpoints, EcstoreExpiryState,
+    EcstoreInstanceContext, EcstorePoolEndpoints, ecstore_config_init, ecstore_init_bucket_metadata_sys,
+    ecstore_init_local_disks_with_instance_ctx, ecstore_new_disk,
 };
 use tokio_util::sync::CancellationToken;
 use uuid::Uuid;
@@ -123,7 +123,7 @@ pub use storage_api::scan::{
     SCANNER_DIRTY_USAGE_SNAPSHOT_PROTOCOL_VERSION, SCANNER_DIRTY_USAGE_SNAPSHOT_RPC_MAX_MESSAGE_SIZE,
     SCANNER_SCOPED_DIRTY_USAGE_ACK_MAX_ENTRIES,
 };
-pub use workload_admission::set_scanner_workload_admission_snapshot_provider;
+pub use workload_admission::{set_scanner_node_admission, set_scanner_workload_admission_snapshot_provider};
 
 static SCANNER_ACTIVE_WORK_UNITS: AtomicU64 = AtomicU64::new(0);
 static SCANNER_RUNTIME_INSTANCES: AtomicU64 = AtomicU64::new(0);
@@ -678,8 +678,37 @@ fn reset_tier_name_cache_for_test() {
     TIER_REGISTRY_GENERATION.store(0, Ordering::Relaxed);
 }
 
-pub(crate) async fn enqueue_runtime_free_version(oi: ScannerObjectInfo) {
-    ecstore_expiry_state_handle().write().await.enqueue_free_version(oi);
+// Only a task running an isolated unit test can override these handles.
+#[cfg(test)]
+struct ExpiryLockTestContext {
+    state: Arc<tokio::sync::RwLock<EcstoreExpiryState>>,
+    store: Option<Arc<ECStore>>,
+    completed_incarnation_reads: Arc<std::sync::atomic::AtomicUsize>,
+}
+
+#[cfg(test)]
+tokio::task_local! {
+    static EXPIRY_LOCK_TEST_CONTEXT: ExpiryLockTestContext;
+}
+
+pub(crate) async fn enqueue_runtime_free_version(oi: ScannerObjectInfo, cancellation: Option<&CancellationToken>) {
+    #[cfg(test)]
+    let state = EXPIRY_LOCK_TEST_CONTEXT
+        .try_with(|context| context.state.clone())
+        .unwrap_or_else(|_| ecstore_expiry_state_handle());
+    #[cfg(not(test))]
+    let state = ecstore_expiry_state_handle();
+    let state = match cancellation {
+        Some(cancel) => tokio::select! {
+            biased;
+            _ = cancel.cancelled() => return,
+            state = state.write() => state,
+        },
+        None => state.write().await,
+    };
+    if !cancellation.is_some_and(CancellationToken::is_cancelled) {
+        state.enqueue_free_version(oi);
+    }
 }
 
 pub(crate) async fn enqueue_runtime_newer_noncurrent(
@@ -687,20 +716,50 @@ pub(crate) async fn enqueue_runtime_newer_noncurrent(
     to_delete_objs: Vec<ObjectToDelete>,
     event: Event,
     src: &LcEventSrc,
+    cancellation: Option<&CancellationToken>,
 ) -> bool {
-    let Some(store) = ecstore_resolve_object_store_handle() else {
+    if cancellation.is_some_and(CancellationToken::is_cancelled) {
+        return false;
+    }
+    #[cfg(test)]
+    let store = EXPIRY_LOCK_TEST_CONTEXT
+        .try_with(|context| context.store.clone())
+        .unwrap_or_else(|_| ecstore_resolve_object_store_handle());
+    #[cfg(not(test))]
+    let store = ecstore_resolve_object_store_handle();
+    let Some(store) = store else {
         return false;
     };
     let Ok(bucket_incarnation_id) = store.bucket_incarnation_id(bucket).await else {
         return false;
     };
-    ecstore_expiry_state_handle().write().await.enqueue_by_newer_noncurrent(
-        bucket,
-        to_delete_objs,
-        event,
-        src,
-        bucket_incarnation_id,
-    )
+    #[cfg(test)]
+    let _ = EXPIRY_LOCK_TEST_CONTEXT.try_with(|context| {
+        context
+            .completed_incarnation_reads
+            .fetch_add(1, std::sync::atomic::Ordering::SeqCst);
+    });
+    if cancellation.is_some_and(CancellationToken::is_cancelled) {
+        return false;
+    }
+    #[cfg(test)]
+    let state = EXPIRY_LOCK_TEST_CONTEXT
+        .try_with(|context| context.state.clone())
+        .unwrap_or_else(|_| ecstore_expiry_state_handle());
+    #[cfg(not(test))]
+    let state = ecstore_expiry_state_handle();
+    let mut state = match cancellation {
+        Some(cancel) => tokio::select! {
+            biased;
+            _ = cancel.cancelled() => return false,
+            state = state.write() => state,
+        },
+        None => state.write().await,
+    };
+    if cancellation.is_some_and(CancellationToken::is_cancelled) {
+        return false;
+    }
+    state.enqueue_by_newer_noncurrent(bucket, to_delete_objs, event, src, bucket_incarnation_id)
 }
 
 pub(crate) async fn queue_replication_heal(

crates/scanner/src/remote_scanner/stream.rs

@@ -705,7 +705,7 @@ async fn scan_and_persist_local_bucket(
         RemoteScannerServerError::worker("remote namespace scanner cache publication is blocked by data movement")
     })?;
     let cache_name = path_join_buf(&[&bucket, DATA_USAGE_CACHE_NAME]);
-    let guard = acquire_scanner_cache_locks(set.as_ref(), &cache_name, source)
+    let mut guard = acquire_scanner_cache_locks(set.as_ref(), &cache_name, source)
         .await
         .map_err(|err| {
             if err.is_contention() {
@@ -791,19 +791,23 @@ async fn scan_and_persist_local_bucket(
 
     let set_disks = scanner_set_disk_inventory(set.as_ref()).await;
     let (checkpoint_tx, mut checkpoint_rx) = mpsc::channel::<DataUsageCache>(1);
+    let (node_tx, mut node_rx) = crate::workload_admission::scanner_node_request_channel();
     let scan_ctx = ctx.child_token();
-    let scan = ScannerIODisk::nsscanner_disk(
-        disk.clone(),
-        scan_ctx.clone(),
-        budget,
-        set_disks,
-        cache,
-        None,
-        ScannerDiskScanOptions {
-            scan_mode,
-            prefix_scan_scope: None,
-            checkpoint_tx: Some(checkpoint_tx),
-        },
+    let scan = crate::workload_admission::with_scanner_node_requests(
+        node_tx,
+        ScannerIODisk::nsscanner_disk(
+            disk.clone(),
+            scan_ctx.clone(),
+            budget,
+            set_disks,
+            cache,
+            None,
+            ScannerDiskScanOptions {
+                scan_mode,
+                prefix_scan_scope: None,
+                checkpoint_tx: Some(checkpoint_tx),
+            },
+        ),
     );
     tokio::pin!(scan);
     let fence_watch = watch_remote_scanner_request_fence(next_cycle, leader_epoch, store.clone(), NS_SCANNER_FENCE_POLL_INTERVAL);
@@ -813,6 +817,27 @@ async fn scan_and_persist_local_bucket(
     let mut checkpoint_channel_closed = false;
     let outcome = loop {
         tokio::select! {
+            request = async {
+                match node_rx.as_mut() {
+                    Some(receiver) => receiver.recv().await,
+                    None => std::future::pending().await,
+                }
+            } => {
+                let Some(request) = request else {
+                    node_rx = None;
+                    continue;
+                };
+                if let Err(error) = wait_for_remote_node_resumption(
+                    guard.resume_node_operation(set.clone(), &cache_name, source, &revisions, request),
+                    fence_watch.as_mut(),
+                ).await {
+                    scan_ctx.cancel();
+                    let _ = tokio::time::timeout(NS_SCANNER_LOCK_LOSS_SHUTDOWN_TIMEOUT, scan.as_mut()).await;
+                    return Err(RemoteScannerServerError::retry_bucket(format!(
+                        "remote namespace scanner could not resume node admission: {error}",
+                    )));
+                }
+            }
             result = &mut scan => {
                 match result {
                     Ok(outcome) => break outcome,
@@ -1121,6 +1146,22 @@ pub(crate) async fn scan_remote_bucket(
     result
 }
 
+/// Resource waits must keep checking the persisted leader fence.
+async fn wait_for_remote_node_resumption<F, G>(resume: F, fence_watch: Pin<&mut G>) -> Result<(), StorageError>
+where
+    F: Future<Output = Result<(), StorageError>>,
+    G: Future<Output = Result<(), ScannerError>>,
+{
+    tokio::select! {
+        biased;
+        result = fence_watch => Err(match result {
+            Ok(()) => StorageError::other("remote namespace scanner fence watcher stopped unexpectedly"),
+            Err(error) => StorageError::other(error),
+        }),
+        result = resume => result,
+    }
+}
+
 fn finish_remote_scanner_stream(
     result: RemoteScannerStreamResult<RemoteScannerOutcome>,
     budget: &ScannerCycleBudget,

crates/scanner/src/remote_scanner/stream/tests.rs

@@ -1006,6 +1006,58 @@ async fn fence_watcher_stops_work_after_persisted_leader_changes() {
     assert!(err.to_string().contains("requested_epoch=9"));
 }
 
+#[tokio::test]
+async fn node_admission_wait_does_not_hide_replacement_leader() {
+    use rustfs_concurrency::adaptive::{FeedbackController, FeedbackObservation, NodeAdmission, ResourcePressure};
+    use std::num::NonZeroU16;
+
+    let store = Arc::new(MutableCycleStateStore {
+        state: RwLock::new(crate::scanner::encode_scanner_cycle_fence_for_test(7, 9)),
+    });
+    let cache = Mutex::new(None);
+    let refresh = AsyncMutex::new(());
+    let watcher = watch_remote_scanner_request_fence_with_cache(
+        7,
+        9,
+        store.clone(),
+        Duration::from_millis(5),
+        &cache,
+        &refresh,
+        Duration::from_millis(5),
+    );
+    tokio::pin!(watcher);
+    let gate = NodeAdmission::new(NonZeroU16::new(1).expect("one shared node unit"));
+    let storage_polled = AtomicBool::new(false);
+    {
+        let resume = async {
+            let _permit = gate.acquire().await;
+            storage_polled.store(true, Ordering::Relaxed);
+            Ok(())
+        };
+        let waiting = wait_for_remote_node_resumption(resume, watcher.as_mut());
+        tokio::pin!(waiting);
+        assert!(futures::poll!(&mut waiting).is_pending(), "no resource sample grants a node unit");
+        *store.state.write().expect("persist replacement leader") = crate::scanner::encode_scanner_cycle_fence_for_test(7, 10);
+        let error = tokio::time::timeout(Duration::from_millis(100), waiting)
+            .await
+            .expect("resource pause must not hide a changed leader")
+            .expect_err("old leader cannot resume storage work");
+        assert!(error.to_string().contains("requested_epoch=9"));
+    }
+    assert!(!storage_polled.load(Ordering::Relaxed));
+    assert_eq!(gate.snapshot().active, 0);
+    gate.update(
+        &mut FeedbackController::new(),
+        Some(FeedbackObservation {
+            generation: 1,
+            max_concurrency: 1,
+            pressure: ResourcePressure::Unknown,
+            completed_units: None,
+        }),
+    );
+    assert!(gate.try_acquire().is_some(), "failed fencing drops the old node queue ticket");
+}
+
 #[tokio::test]
 async fn concurrent_cycle_cache_misses_share_one_backend_read() {
     let request = RemoteScannerRequest(test_request(Uuid::new_v4()));

crates/scanner/src/scanner_folder.rs

@@ -43,6 +43,7 @@ use crate::storage_api::owner::{
 };
 #[cfg(test)]
 use crate::storage_api::owner::{EcstoreExpirationStatus as ExpirationStatus, EcstoreLifecycleRule as LifecycleRule};
+use crate::workload_admission::run_scanner_node_operation;
 use metrics::{counter, describe_counter};
 use rustfs_common::trace_bus::{TraceEvent, TraceFunc, TraceKind, trace_emit, trace_subscriber_count};
 use rustfs_filemeta::{
@@ -795,6 +796,7 @@ pub struct FolderScanner {
     resolved_failed_object_paths: HashSet<String>,
 
     sleeper: DynamicSleeper,
+    node_admission: Option<Arc<rustfs_concurrency::adaptive::NodeAdmission>>,
     // should_heal: Arc<dyn Fn() -> bool + Send + Sync>,
     disks: Vec<Arc<Disk>>,
     disks_quorum: usize,
@@ -828,6 +830,8 @@ pub struct FolderScanner {
     pending_size_reconciliation_truncated: bool,
     #[cfg(test)]
     list_path_raw_options_observer: Option<mpsc::UnboundedSender<ListPathRawTimeoutSnapshot>>,
+    #[cfg(test)]
+    defer_abandoned_entries_until_finished: bool,
 }
 
 struct RawEnumerationProgress {
@@ -998,12 +1002,13 @@ async fn next_scanner_dir_entry(
     ctx: &CancellationToken,
     sleeper: &DynamicSleeper,
     entries: &mut ScannerDirectory,
+    admission: Option<&Arc<rustfs_concurrency::adaptive::NodeAdmission>>,
 ) -> Result<Option<tokio::fs::DirEntry>, ScannerError> {
     if entries.batch_entries == SCANNER_DIRECTORY_BATCH_ENTRIES {
         wait_for_scanner_io(ctx, tokio::task::yield_now()).await?;
         entries.batch_entries = 0;
     }
-    let entry = wait_for_scanner_io(ctx, entries.next_entry()).await??;
+    let entry = wait_for_scanner_io(ctx, run_scanner_node_operation(admission, ctx, entries.next_entry())).await???;
     if entry.is_some() {
         // Tokio prefetches bounded chunks. Pacing consumption also paces the
         // next refill, without charging an extra entry for EOF.
@@ -1923,7 +1928,12 @@ impl FolderScanner {
             // directory that vanished during iteration instead of failing the
             // whole parent subtree. The bucket root (no parent) still propagates
             // NotFound so namespace removal is detected by the caller.
-            let mut dir_reader = match wait_for_scanner_io(&ctx, ScannerDirectory::open(&dir_path)).await? {
+            let mut dir_reader = match wait_for_scanner_io(
+                &ctx,
+                run_scanner_node_operation(self.node_admission.as_ref(), &ctx, ScannerDirectory::open(&dir_path)),
+            )
+            .await??
+            {
                 Ok(dir_reader) => Some(dir_reader),
                 Err(e)
                     if folder.parent.is_some()
@@ -1961,7 +1971,7 @@ impl FolderScanner {
                 // Hold at most one metadata entry until a candidate reaches
                 // EOF: a later part must not leave object accounting or ILM work.
                 let (entry, replayed_metadata) = if let Some(reader) = dir_reader.as_mut() {
-                    let entry = match next_scanner_dir_entry(&ctx, &self.sleeper, reader).await {
+                    let entry = match next_scanner_dir_entry(&ctx, &self.sleeper, reader, self.node_admission.as_ref()).await {
                         Ok(Some(entry)) => entry,
                         Ok(None) => {
                             raw_enumeration_complete = true;
@@ -2072,7 +2082,12 @@ impl FolderScanner {
 
                 // Ignore entries that disappeared during traversal or hit symlink
                 // loops, but propagate other walk errors.
-                let mut entry_type = match wait_for_scanner_io(&ctx, entry.file_type()).await? {
+                let mut entry_type = match wait_for_scanner_io(
+                    &ctx,
+                    run_scanner_node_operation(self.node_admission.as_ref(), &ctx, entry.file_type()),
+                )
+                .await??
+                {
                     Ok(entry_type) => entry_type,
                     Err(e) if e.kind() == ErrorKind::NotFound => {
                         debug!(
@@ -2123,7 +2138,12 @@ impl FolderScanner {
                 let mut entry_metadata_len = None;
                 if entry_type.is_symlink() {
                     wait_for_scanner_io(&ctx, self.sleeper.admit_disk_io(1, 0)).await?;
-                    let metadata = match wait_for_scanner_io(&ctx, tokio::fs::metadata(&file_path)).await? {
+                    let metadata = match wait_for_scanner_io(
+                        &ctx,
+                        run_scanner_node_operation(self.node_admission.as_ref(), &ctx, tokio::fs::metadata(&file_path)),
+                    )
+                    .await??
+                    {
                         Ok(metadata) => metadata,
                         Err(e) if e.kind() == ErrorKind::NotFound => {
                             debug!(
@@ -2274,22 +2294,30 @@ impl FolderScanner {
                         len
                     } else {
                         wait_for_scanner_io(&ctx, self.sleeper.admit_disk_io(1, 0)).await?;
-                        wait_for_scanner_io(&ctx, tokio::fs::metadata(&item.path))
-                            .await?
-                            .map(|metadata| metadata.len())
-                            .unwrap_or(0)
+                        wait_for_scanner_io(
+                            &ctx,
+                            run_scanner_node_operation(self.node_admission.as_ref(), &ctx, tokio::fs::metadata(&item.path)),
+                        )
+                        .await??
+                        .map(|metadata| metadata.len())
+                        .unwrap_or(0)
                     }
                 } else {
                     0
                 };
                 wait_for_scanner_io(&ctx, self.sleeper.admit_disk_io(1, budgeted_bytes)).await?;
 
-                self.object_metadata_visits.increment(1);
-                let sz = match self
-                    .local_disk
-                    .get_size_with_tier_names(item.clone(), &self.tier_registry.names)
-                    .await
-                {
+                let size_result = run_scanner_node_operation(self.node_admission.as_ref(), &ctx, async {
+                    self.object_metadata_visits.increment(1);
+                    self.local_disk
+                        .get_size_with_tier_names(item.clone(), &self.tier_registry.names)
+                        .await
+                })
+                .await?;
+                if self.node_admission.is_some() && ctx.is_cancelled() {
+                    return Err(ScannerError::Other("Operation cancelled".to_string()));
+                }
+                let sz = match size_result {
                     Ok(sz) => sz,
                     Err(e) => {
                         let failure_action = classify_get_size_failure(&item, &e);
@@ -2606,7 +2634,7 @@ impl FolderScanner {
                     {
                         Ok(outcome) => outcome,
                         Err(e) => {
-                            if ctx.is_cancelled() {
+                            if ctx.is_cancelled() || matches!(&e, ScannerError::ResourceDeferred) {
                                 self.preserve_partial_child_progress(&folder_item.parent, &h, into, &dst)
                                     .await;
                                 return Err(e);
@@ -2847,19 +2875,23 @@ impl FolderScanner {
                 let mut seen_truncated_objects: HashSet<String> = HashSet::new();
 
                 loop {
-                    if agreed_closed && partial_closed && finished_closed {
+                    if child_ctx.is_cancelled() || (agreed_closed && partial_closed && finished_closed) {
                         break;
                     }
+                    #[cfg(test)]
+                    let defer_entries = self.defer_abandoned_entries_until_finished && !finished_closed;
+                    #[cfg(not(test))]
+                    let defer_entries = false;
 
                     select! {
-                        entry_name = agreed_rx.recv(), if !agreed_closed => {
+                        entry_name = agreed_rx.recv(), if !agreed_closed && !defer_entries => {
                             let Some(entry_name) = entry_name else {
                                 agreed_closed = true;
                                 continue;
                             };
                             (self.update_current_path)(&entry_name).await;
                         }
-                        entries = partial_rx.recv(), if !partial_closed => {
+                        entries = partial_rx.recv(), if !partial_closed && !defer_entries => {
                             let Some(entries) = entries else {
                                 partial_closed = true;
                                 continue;
@@ -2985,6 +3017,7 @@ impl FolderScanner {
                                 finished_closed = true;
                                 continue;
                             };
+                            finished_closed = true;
                             if disk_errors_are_only_missing_paths(&errs) {
                                 debug!(
                                     target: "rustfs::scanner::folder",
@@ -3006,7 +3039,9 @@ impl FolderScanner {
                                     "Scanner list_path_raw finished with disk errors"
                                 );
                             }
-                            child_ctx.cancel();
+                            // The producer awaited callback sends, not their
+                            // consumption. Drain the remaining candidate and
+                            // agreed frames before closing this child walk.
                         }
                         _ = child_ctx.cancelled() => {
                             break;
@@ -3024,7 +3059,10 @@ impl FolderScanner {
                     if into.compacted {
                         // In compacted mode child totals are accumulated directly into the parent entry.
                         let fut = Box::pin(self.scan_folder(ctx.clone(), folder_item.clone(), into));
-                        fut.await.map_err(|e| ScannerError::Other(e.to_string()))?;
+                        fut.await.map_err(|error| match error {
+                            ScannerError::ResourceDeferred => ScannerError::ResourceDeferred,
+                            other => ScannerError::Other(other.to_string()),
+                        })?;
                         self.send_update_for_entry(&this_hash, &folder.parent, into).await;
                         tokio::task::yield_now().await;
                     } else {
@@ -3043,7 +3081,7 @@ impl FolderScanner {
                             )
                             .await
                         {
-                            if ctx.is_cancelled() {
+                            if ctx.is_cancelled() || matches!(&e, ScannerError::ResourceDeferred) {
                                 self.preserve_partial_child_progress(&folder_item.parent, &h, into, &dst)
                                     .await;
                                 return Err(e);
@@ -3217,6 +3255,7 @@ pub(crate) async fn scan_data_folder_scoped(
         failed_object_paths_seen: HashSet::new(),
         resolved_failed_object_paths: HashSet::new(),
         sleeper,
+        node_admission: crate::workload_admission::scanner_node_admission(),
         disks,
         disks_quorum,
         usage_updates,
@@ -3244,6 +3283,8 @@ pub(crate) async fn scan_data_folder_scoped(
         pending_size_reconciliation_truncated: false,
         #[cfg(test)]
         list_path_raw_options_observer: None,
+        #[cfg(test)]
+        defer_abandoned_entries_until_finished: false,
     };
 
     let now = FolderScanner::now_secs();
@@ -3333,7 +3374,7 @@ pub(crate) async fn scan_data_folder_scoped(
             }
         }
         Err(e) => {
-            if ctx.is_cancelled() {
+            if ctx.is_cancelled() || matches!(&e, ScannerError::ResourceDeferred) {
                 let root_hash = hash_path(&bucket_name);
                 let root_has_progress = data_usage_root_has_progress(&root);
                 let pending_heals_changed = scanner.pending_heals_changed;
@@ -3408,6 +3449,19 @@ pub(crate) async fn scan_data_folder_scoped(
                 close_disk_guard.close().await;
                 return Err(ScannerError::NamespaceNotFoundCache(Box::new(partial_cache)));
             }
+            if matches!(&e, ScannerError::ResourceDeferred) {
+                // Admission pressure is not disk failure or an empty census.
+                // Keep the previous tree when no new useful progress exists.
+                let mut partial_cache = scanner.old_cache;
+                if partial_cache.cache.is_empty() {
+                    partial_cache
+                        .cache
+                        .insert(hash_path(&bucket_name).0, DataUsageEntry::default());
+                }
+                partial_cache.info.snapshot_complete = false;
+                close_disk_guard.close().await;
+                return Err(ScannerError::PartialCache(Box::new(partial_cache)));
+            }
             close_disk_guard.close().await;
             // No useful information, return original cache
             Err(e)
@@ -3427,3 +3481,15 @@ pub(crate) use tests::checkpoint_fixture::run_checkpoint_fixture;
 
 #[cfg(test)]
 mod tests;
+
+#[cfg(test)]
+tokio::task_local! {
+    pub(crate) static TEST_SIZE_DISPATCH_BOUNDARIES: tokio::sync::mpsc::UnboundedSender<&'static str>;
+}
+
+#[cfg(test)]
+pub(crate) fn observe_test_size_dispatch_boundary(stage: &'static str) -> bool {
+    TEST_SIZE_DISPATCH_BOUNDARIES
+        .try_with(|sender| sender.send(stage).is_ok())
+        .unwrap_or(false)
+}

crates/scanner/src/scanner_folder/item_actions.rs

@@ -628,6 +628,22 @@ impl ScannerItem {
         tier_names: &[String],
         size_summary: &mut SizeSummary,
     ) {
+        self.apply_actions_cancellable(object_infos, lock_retention, versioning_config, tier_names, size_summary, None)
+            .await;
+    }
+
+    pub(crate) async fn apply_actions_cancellable(
+        &mut self,
+        object_infos: Vec<ObjectInfo>,
+        lock_retention: Option<Arc<ObjectLockConfiguration>>,
+        versioning_config: VersioningConfiguration,
+        tier_names: &[String],
+        size_summary: &mut SizeSummary,
+        cancellation: Option<&CancellationToken>,
+    ) {
+        if cancellation.is_some_and(CancellationToken::is_cancelled) {
+            return;
+        }
         let object_path = self.object_path();
         if object_infos.is_empty() {
             debug!(
@@ -671,6 +687,9 @@ impl ScannerItem {
         let Some(lifecycle) = self.lifecycle.clone() else {
             let mut cumulative_size: i64 = 0;
             for (oi, resolved_size) in object_infos.iter().zip(resolved_sizes.iter()) {
+                if cancellation.is_some_and(CancellationToken::is_cancelled) {
+                    return;
+                }
                 let accounting_size = match resolved_size {
                     SizeResolution::Known { logical, .. } => *logical,
                     // A valid compressed legacy sentinel has no logical size,
@@ -678,7 +697,7 @@ impl ScannerItem {
                     // physical size is only an input to those operations; it
                     // is not folded into the logical total below.
                     SizeResolution::Unknown { physical, .. } => {
-                        self.heal_actions(oi, *physical, size_summary).await;
+                        self.heal_actions(oi, *physical, size_summary, cancellation).await;
                         size_summary.actions_accounting_unknown(oi);
                         continue;
                     }
@@ -688,13 +707,16 @@ impl ScannerItem {
                     }
                 };
 
-                let size = self.heal_actions(oi, accounting_size, size_summary).await;
+                let size = self.heal_actions(oi, accounting_size, size_summary, cancellation).await;
 
                 size_summary.actions_accounting(oi, size, accounting_size);
 
                 cumulative_size = cumulative_size.saturating_add(size);
             }
 
+            if cancellation.is_some_and(CancellationToken::is_cancelled) {
+                return;
+            }
             self.alert_excessive_versions(object_infos.len(), cumulative_size);
 
             debug!(
@@ -736,6 +758,10 @@ impl ScannerItem {
             }
         };
 
+        if cancellation.is_some_and(CancellationToken::is_cancelled) {
+            return;
+        }
+
         // Every version handed to the evaluator counts as an ILM-checked
         // version, whether or not a rule matched (NoneAction included). This is
         // reached only for buckets with lifecycle rules; it feeds
@@ -754,6 +780,9 @@ impl ScannerItem {
             .all(|candidate| Self::tier_is_known(candidate, tier_names));
         'eventLoop: {
             for (i, event) in events.iter().enumerate() {
+                if cancellation.is_some_and(CancellationToken::is_cancelled) {
+                    return;
+                }
                 let oi = &object_infos[i];
                 let known_size = resolved_sizes[i].known_size();
                 if has_corrupt_size
@@ -772,7 +801,7 @@ impl ScannerItem {
                     // accounting. Size-filtered or deferred events remain
                     // pending, so retain the version-only physical counters.
                     if let SizeResolution::Unknown { physical, .. } = &resolved_sizes[i] {
-                        self.heal_actions(oi, *physical, size_summary).await;
+                        self.heal_actions(oi, *physical, size_summary, cancellation).await;
                         size_summary.actions_accounting_unknown(oi);
                     }
                     continue;
@@ -829,7 +858,7 @@ impl ScannerItem {
                                     noncurrent_unknown.push(oi);
                                 } else {
                                     if let SizeResolution::Unknown { physical, .. } = &resolved_sizes[i] {
-                                        self.heal_actions(oi, *physical, size_summary).await;
+                                        self.heal_actions(oi, *physical, size_summary, cancellation).await;
                                     }
                                     size_summary.actions_accounting_unknown(oi);
                                 }
@@ -846,7 +875,7 @@ impl ScannerItem {
                             }
                             IlmAction::NoneAction | IlmAction::ActionCount => {
                                 if let SizeResolution::Unknown { physical, .. } = &resolved_sizes[i] {
-                                    self.heal_actions(oi, *physical, size_summary).await;
+                                    self.heal_actions(oi, *physical, size_summary, cancellation).await;
                                 }
                                 size_summary.actions_accounting_unknown(oi);
                             }
@@ -864,7 +893,7 @@ impl ScannerItem {
                 // side-effecting tier actions fail closed until the registry
                 // recognizes the source again.
                 if Self::action_blocked_by_unknown_tier(event.action, oi, all_versions_known, tier_names, &event.storage_class) {
-                    size = self.heal_actions(oi, actual_size, size_summary).await;
+                    size = self.heal_actions(oi, actual_size, size_summary, cancellation).await;
                     size_summary.actions_accounting(oi, size, actual_size);
                     cumulative_size += size;
                     continue;
@@ -973,7 +1002,7 @@ impl ScannerItem {
                     }
 
                     IlmAction::NoneAction | IlmAction::ActionCount => {
-                        size = self.heal_actions(oi, actual_size, size_summary).await;
+                        size = self.heal_actions(oi, actual_size, size_summary, cancellation).await;
                     }
                 }
 
@@ -984,6 +1013,9 @@ impl ScannerItem {
             }
         }
 
+        if cancellation.is_some_and(CancellationToken::is_cancelled) {
+            return;
+        }
         if !to_delete_objs.is_empty()
             && let Some(event) = noncurrent_events.first().cloned()
         {
@@ -991,7 +1023,8 @@ impl ScannerItem {
             let count = u64::try_from(to_delete_objs.len()).unwrap_or(u64::MAX);
             let done_ilm = Metrics::time_ilm(action);
             let trace_started_at = trace_start_instant();
-            let queued = enqueue_runtime_newer_noncurrent(&self.bucket, to_delete_objs, event, &LcEventSrc::Scanner).await;
+            let queued =
+                enqueue_runtime_newer_noncurrent(&self.bucket, to_delete_objs, event, &LcEventSrc::Scanner, cancellation).await;
             if let Some(trace_started_at) = trace_started_at {
                 let state = if queued { "queued" } else { "not_queued" };
                 trace_emit(|| {
@@ -1022,15 +1055,28 @@ impl ScannerItem {
                 }
             }
         }
-        self.alert_excessive_versions(remaining_versions, cumulative_size);
+        if !cancellation.is_some_and(CancellationToken::is_cancelled) {
+            self.alert_excessive_versions(remaining_versions, cumulative_size);
+        }
     }
 
-    pub(super) async fn heal_actions(&mut self, oi: &ObjectInfo, actual_size: i64, size_summary: &mut SizeSummary) -> i64 {
+    pub(super) async fn heal_actions(
+        &mut self,
+        oi: &ObjectInfo,
+        actual_size: i64,
+        size_summary: &mut SizeSummary,
+        cancellation: Option<&CancellationToken>,
+    ) -> i64 {
+        if cancellation.is_some_and(CancellationToken::is_cancelled) {
+            return actual_size;
+        }
         if self.heal_enabled {
             self.enqueue_heal(oi).await;
         }
 
-        self.heal_replication(oi, size_summary).await;
+        if !cancellation.is_some_and(CancellationToken::is_cancelled) {
+            self.heal_replication(oi, size_summary).await;
+        }
 
         actual_size
     }

crates/scanner/src/scanner_folder/tests.rs

@@ -30,7 +30,9 @@ use std::sync::Mutex;
 pub(super) mod checkpoint_fixture;
 pub(super) mod enumeration_restart;
 mod incremental_enumeration;
+mod listing_completion;
 mod metadata_visits;
+mod node_admission;
 mod usage_updates;
 
 /// Reset the process-global alert cooldown map; test-only.
@@ -364,6 +366,7 @@ async fn build_test_scanner() -> (FolderScanner, std::path::PathBuf) {
         failed_object_paths_seen: HashSet::new(),
         resolved_failed_object_paths: HashSet::new(),
         sleeper: SCANNER_SLEEPER.clone(),
+        node_admission: None,
         disks: Vec::new(),
         disks_quorum: 0,
         usage_updates: None,
@@ -394,6 +397,7 @@ async fn build_test_scanner() -> (FolderScanner, std::path::PathBuf) {
         pending_size_reconciliation_scopes: HashSet::new(),
         pending_size_reconciliation_truncated: false,
         list_path_raw_options_observer: None,
+        defer_abandoned_entries_until_finished: false,
     };
 
     (scanner, temp_dir)
@@ -2262,7 +2266,7 @@ async fn test_heal_actions_returns_actual_size_without_inline_heal() {
     };
     let mut size_summary = SizeSummary::default();
 
-    let size = item.heal_actions(&object_info, 123, &mut size_summary).await;
+    let size = item.heal_actions(&object_info, 123, &mut size_summary, None).await;
     assert_eq!(size, 123);
 }
 

crates/scanner/src/scanner_folder/tests/listing_completion.rs

@@ -0,0 +1,104 @@
+// Copyright 2026 RustFS Team
+// Licensed under the Apache License, Version 2.0.
+
+use super::*;
+
+#[tokio::test]
+#[serial]
+async fn abandoned_listing_drains_candidate_buffered_before_finished() {
+    let (mut scanner, root) = build_test_scanner().await;
+    let _guard = TestGuard {
+        temp_dir: Some(root.clone()),
+    };
+    let bucket = "bucket";
+    let object = "abandoned/object";
+    tokio::fs::create_dir_all(root.join(bucket)).await.expect("local bucket");
+    let mut disks = vec![scanner.local_disk.clone()];
+    let mut original_metadata = Vec::new();
+    for (index, version) in [(2, 0x1935), (3, 0x1935), (4, 0x1934)] {
+        let disk_root = root.join(format!("disk-{index}"));
+        let metadata = metadata_for_object_version(bucket, object, Some(Uuid::from_u128(version)));
+        write_test_object_metadata_bytes(&disk_root, bucket, object, &metadata).await;
+        original_metadata.push((disk_root.join(bucket).join(object).join(STORAGE_FORMAT_FILE), metadata));
+        let endpoint = Endpoint::try_from(disk_root.to_string_lossy().as_ref()).expect("listing fixture endpoint");
+        disks.push(
+            new_disk(
+                &endpoint,
+                &DiskOption {
+                    cleanup: false,
+                    health_check: false,
+                },
+            )
+            .await
+            .expect("listing fixture disk"),
+        );
+    }
+    for cache in [&mut scanner.old_cache, &mut scanner.new_cache] {
+        cache.info.name = bucket.to_owned();
+    }
+    scanner.old_cache.replace(
+        "bucket/abandoned/object",
+        bucket,
+        DataUsageEntry {
+            objects: 1,
+            ..Default::default()
+        },
+    );
+    scanner.heal_object_select = 1;
+    scanner.disks = disks;
+    scanner.disks_quorum = 2;
+    scanner.sleeper = DynamicSleeper::new(rustfs_config::ScannerSpeed::Fastest);
+    // Force the valid select ordering that receives terminal errors before the
+    // final candidate. One candidate frame fits in the bounded partial channel.
+    scanner.defer_abandoned_entries_until_finished = true;
+    let (_commands, mut heal_rx) = rustfs_heal_contracts::heal_channel::init_heal_channels().expect("isolated heal channel");
+    let (captured_tx, mut captured_rx) = mpsc::unbounded_channel();
+    let responder = tokio::spawn(async move {
+        while let Some(command) = heal_rx.recv().await {
+            let rustfs_heal_contracts::heal_channel::HealReceiptCommand { request, response_tx } = command;
+            captured_tx
+                .send((request.object_prefix.clone(), request.object_version_id.clone()))
+                .expect("candidate capture remains open");
+            let _ = response_tx.send(Ok(rustfs_heal_contracts::heal_channel::HealAdmissionReceipt {
+                result: HealAdmissionResult::Accepted,
+                task_id: request.id,
+            }));
+        }
+    });
+    let result = tokio::time::timeout(
+        Duration::from_secs(2),
+        scanner.scan_folder(
+            CancellationToken::new(),
+            CachedFolder {
+                name: bucket.to_owned(),
+                parent: None,
+                object_heal_prob_div: 1,
+            },
+            &mut DataUsageEntry::default(),
+        ),
+    )
+    .await;
+    responder.abort();
+    result
+        .expect("listing completion must close every callback channel")
+        .expect("complete folder scan");
+    let mut candidates = HashSet::new();
+    while let Ok((object, version)) = captured_rx.try_recv() {
+        if let (Some(object), Some(version)) = (object, version) {
+            candidates.insert((object, version));
+        }
+    }
+    let expected = [0x1934, 0x1935]
+        .into_iter()
+        // Raw base-object listings include the trailing separator. Preserve
+        // the producer's candidate identity when draining its callback frame.
+        .map(|version| (format!("{object}/"), Uuid::from_u128(version).to_string()))
+        .collect();
+    assert_eq!(
+        candidates, expected,
+        "terminal disk errors must not discard buffered exact-version candidates"
+    );
+    for (path, metadata) in original_metadata {
+        assert_eq!(tokio::fs::read(path).await.expect("retained metadata"), metadata);
+    }
+}

crates/scanner/src/scanner_io/cache.rs

@@ -172,12 +172,55 @@ fn record_checkpoint_save_failure(cache_name: &str, checkpoint: &DataUsageCache,
 
 #[derive(Debug)]
 pub(crate) struct ScannerCacheLockGuards {
-    scoped: NamespaceLockGuard,
+    scoped: Option<NamespaceLockGuard>,
 }
 
 impl ScannerCacheLockGuards {
     pub(crate) fn is_lock_lost(&self) -> bool {
-        self.scoped.is_lock_lost()
+        self.scoped.as_ref().is_none_or(NamespaceLockGuard::is_lock_lost)
+    }
+
+    /// Suspend the same traversal while yielding its cache lease. Lock order on
+    /// resumption is node admission -> cache lease -> cache revision reads.
+    pub(crate) async fn resume_node_operation(
+        &mut self,
+        store: Arc<SetDisks>,
+        cache_name: &str,
+        source: DataUsageCacheSource,
+        revisions: &DataUsageCacheRevisions,
+        request: crate::workload_admission::ScannerNodeRequest,
+    ) -> Result<()> {
+        if self.is_lock_lost() {
+            return Err(Error::other("scanner cache lock was lost before node admission"));
+        }
+        if request.respond.is_closed() {
+            return Ok(());
+        }
+        let crate::workload_admission::ScannerNodeRequest { owner, respond, cancel } = request;
+        drop(self.scoped.take());
+        let resume = async {
+            let permit = owner.acquire().await;
+            *self = acquire_scanner_cache_locks(store.as_ref(), cache_name, source)
+                .await
+                .map_err(Error::other)?;
+            let current = crate::storage_api::ecstore_with_background_disk_io(
+                cancel.clone(),
+                DataUsageCache::read_revisions(store, cache_name),
+            )
+            .await?;
+            if self.is_lock_lost() || &current != revisions {
+                return Err(Error::other("scanner cache changed while waiting for node admission"));
+            }
+            // If the walk was dropped, send returns ownership and drops the
+            // permit without recording completed work.
+            let _ = respond.send(permit);
+            Ok(())
+        };
+        tokio::select! {
+            biased;
+            _ = cancel.cancelled() => Err(Error::other("scanner node admission cancelled")),
+            result = resume => result,
+        }
     }
 }
 
@@ -215,6 +258,15 @@ impl std::fmt::Display for ScannerCacheLockError {
     }
 }
 
+impl std::error::Error for ScannerCacheLockError {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match self {
+            Self::Create { source, .. } => Some(source),
+            Self::Acquire { source, .. } => Some(source),
+        }
+    }
+}
+
 pub(crate) async fn acquire_scanner_cache_locks(
     store: &SetDisks,
     cache_name: &str,
@@ -237,7 +289,7 @@ pub(crate) async fn acquire_scanner_cache_locks(
             source,
         })?;
 
-    Ok(ScannerCacheLockGuards { scoped })
+    Ok(ScannerCacheLockGuards { scoped: Some(scoped) })
 }
 
 pub(super) async fn await_scanner_disk_shutdown<F>(scan: Pin<&mut F>)
@@ -688,6 +740,15 @@ pub(super) fn completed_data_usage_info(
         .map(|candidate| (candidate.data, candidate.last_update))
 }
 
+/// Certify an incarnation only when every contributing set reports the same non-nil identity.
+fn certified_bucket_incarnation(results: &[DataUsageCache], bucket: &str) -> Option<uuid::Uuid> {
+    let mut identities = results
+        .iter()
+        .map(|result| result.info.scan_bucket_incarnations.get(bucket).copied());
+    let first = identities.next().flatten().filter(|id| !id.is_nil())?;
+    identities.all(|id| id == Some(first)).then_some(first)
+}
+
 pub(super) fn completed_usage_candidate(
     results: &[DataUsageCache],
     scope: &ScannerSnapshotScope<'_>,
@@ -740,7 +801,11 @@ pub(super) fn completed_usage_candidate(
         let merged_last_update = validated.last_update;
         let buckets_usage = bucket_entries
             .into_iter()
-            .map(|(bucket, entry)| Ok((bucket, checked_bucket_usage_info(entry).ok_or(CandidateOutcome::UsageCounters)?)))
+            .map(|(bucket, entry)| {
+                let mut usage = checked_bucket_usage_info(entry).ok_or(CandidateOutcome::UsageCounters)?;
+                usage.bucket_incarnation = certified_bucket_incarnation(results, &bucket).map(|id| id.to_string());
+                Ok((bucket, usage))
+            })
             .collect::<std::result::Result<HashMap<_, _>, CandidateOutcome>>()?;
         let bucket_sizes = buckets_usage
             .iter()

crates/scanner/src/scanner_io/dirty_usage.rs

@@ -238,6 +238,71 @@ pub enum ScannerDurableDirtyUsageReplayScope {
     TopLevelEntries { entries: BTreeSet<String> },
 }
 
+impl ScannerDurableDirtyUsageReplayRecord {
+    /// Replays decoded producer hints with the canonical byte limit and semantic checks.
+    ///
+    /// Callers must retain their framing and owner checks. This performs the same
+    /// state update as [`replay_durable_dirty_usage_producer_record`]; it does not
+    /// establish storage-verified source authority.
+    pub fn replay(self) -> std::result::Result<ScannerDirtyUsageState, ScannerDurableDirtyUsageReplayError> {
+        check_durable_dirty_usage_replay_bytes(&self)?;
+        replay_decoded_dirty_usage_record(&self)
+    }
+}
+
+struct ReplayByteLimit {
+    remaining: usize,
+}
+
+impl std::io::Write for ReplayByteLimit {
+    fn write(&mut self, bytes: &[u8]) -> std::io::Result<usize> {
+        self.remaining = self
+            .remaining
+            .checked_sub(bytes.len())
+            .ok_or_else(|| std::io::Error::other("dirty replay byte limit"))?;
+        Ok(bytes.len())
+    }
+
+    fn flush(&mut self) -> std::io::Result<()> {
+        Ok(())
+    }
+}
+
+fn check_durable_dirty_usage_replay_bytes(
+    record: &ScannerDurableDirtyUsageReplayRecord,
+) -> std::result::Result<(), ScannerDurableDirtyUsageReplayError> {
+    // Bound structure traversal and string scanning before counting escaped JSON.
+    // Each entry or prefix contributes at least one additional serialized byte.
+    let mut remaining = SCANNER_DURABLE_DIRTY_USAGE_REPLAY_MAX_BYTES;
+    let mut charge = |size: usize| -> std::result::Result<(), ScannerDurableDirtyUsageReplayError> {
+        remaining = remaining
+            .checked_sub(size)
+            .ok_or(ScannerDurableDirtyUsageReplayError::ByteLimit)?;
+        Ok(())
+    };
+    charge(record.writer_epoch.len())?;
+    charge(record.entries.len())?;
+    for entry in &record.entries {
+        charge(entry.bucket.len())?;
+        if let ScannerDurableDirtyUsageReplayScope::TopLevelEntries { entries } = &entry.scope {
+            charge(entries.len())?;
+            for entry in entries {
+                charge(entry.len())?;
+            }
+        }
+    }
+    let mut limit = ReplayByteLimit {
+        remaining: SCANNER_DURABLE_DIRTY_USAGE_REPLAY_MAX_BYTES,
+    };
+    serde_json::to_writer(&mut limit, record).map_err(|error| {
+        if error.is_io() {
+            ScannerDurableDirtyUsageReplayError::ByteLimit
+        } else {
+            ScannerDurableDirtyUsageReplayError::InvalidJson
+        }
+    })
+}
+
 pub fn encode_durable_dirty_usage_producer_replay_record(
     entries: Vec<ScannerDurableDirtyUsageReplayEntry>,
 ) -> std::result::Result<Vec<u8>, ScannerDurableDirtyUsageReplayError> {
@@ -263,7 +328,13 @@ pub fn replay_durable_dirty_usage_producer_record(
     }
     let record: ScannerDurableDirtyUsageReplayRecord =
         serde_json::from_slice(bytes).map_err(|_| ScannerDurableDirtyUsageReplayError::InvalidJson)?;
-    let replay = validate_durable_dirty_usage_replay_record(&record)?;
+    replay_decoded_dirty_usage_record(&record)
+}
+
+fn replay_decoded_dirty_usage_record(
+    record: &ScannerDurableDirtyUsageReplayRecord,
+) -> std::result::Result<ScannerDirtyUsageState, ScannerDurableDirtyUsageReplayError> {
+    let replay = validate_durable_dirty_usage_replay_record(record)?;
     let max_generation = replay.iter().map(|entry| entry.generation).max().unwrap_or(0);
     set_dirty_usage_generation_floor(max_generation)?;
     let pending = {
@@ -772,6 +843,109 @@ mod scoped_dirty_usage_tests {
         );
     }
 
+    fn decoded_replay_fixture() -> ScannerDurableDirtyUsageReplayRecord {
+        ScannerDurableDirtyUsageReplayRecord {
+            schema: SCANNER_DURABLE_DIRTY_USAGE_REPLAY_SCHEMA,
+            cache_key_format: crate::DATA_USAGE_CACHE_KEY_FORMAT,
+            writer_epoch: "writer".to_string(),
+            entries: vec![ScannerDurableDirtyUsageReplayEntry {
+                bucket: "photos".to_string(),
+                generation: 7,
+                scope: ScannerDurableDirtyUsageReplayScope::TopLevelEntries {
+                    entries: BTreeSet::from(["2026".to_string(), "archive".to_string()]),
+                },
+                producers: SegmentInvalidationProducerIdentity::REQUIRED_PRODUCTION.into_iter().collect(),
+            }],
+        }
+    }
+
+    #[test]
+    #[serial]
+    fn durable_dirty_usage_decoded_replay_matches_byte_replay_at_size_boundary() {
+        let record = decoded_replay_fixture();
+        let fixed_bytes = serde_json::to_vec(&record).expect("fixture encoding").len() - record.writer_epoch.len();
+        for size in [
+            SCANNER_DURABLE_DIRTY_USAGE_REPLAY_MAX_BYTES - 1,
+            SCANNER_DURABLE_DIRTY_USAGE_REPLAY_MAX_BYTES,
+            SCANNER_DURABLE_DIRTY_USAGE_REPLAY_MAX_BYTES + 1,
+        ] {
+            clear_dirty_usage_buckets_for_tests();
+            let mut record = record.clone();
+            record.writer_epoch = "x".repeat(size - fixed_bytes);
+            let bytes = serde_json::to_vec(&record).expect("bounded fixture encoding");
+            assert_eq!(bytes.len(), size);
+            let expected = replay_durable_dirty_usage_producer_record(&bytes);
+            let buckets = dirty_usage_buckets_for_tests();
+            let scopes = dirty_usage_bucket_scopes_for_tests();
+            let identities = dirty_usage_producer_identities().clone();
+            let coverage = DIRTY_USAGE_PRODUCER_COVERAGE.load(Ordering::Acquire);
+
+            clear_dirty_usage_buckets_for_tests();
+            assert_eq!(record.replay(), expected, "canonical size {size}");
+            assert_eq!(dirty_usage_buckets_for_tests(), buckets);
+            assert_eq!(dirty_usage_bucket_scopes_for_tests(), scopes);
+            assert_eq!(*dirty_usage_producer_identities(), identities);
+            assert_eq!(DIRTY_USAGE_PRODUCER_COVERAGE.load(Ordering::Acquire), coverage);
+        }
+        clear_dirty_usage_buckets_for_tests();
+    }
+
+    #[test]
+    fn durable_dirty_usage_decoded_size_counts_escaped_utf8() {
+        for repeats in [6000, 8000] {
+            let mut record = decoded_replay_fixture();
+            record.writer_epoch = "\"\n雪\\".repeat(repeats);
+            let bytes = serde_json::to_vec(&record).expect("escaped fixture encoding");
+            let expected = if bytes.len() > SCANNER_DURABLE_DIRTY_USAGE_REPLAY_MAX_BYTES {
+                Err(ScannerDurableDirtyUsageReplayError::ByteLimit)
+            } else {
+                Ok(())
+            };
+            assert_eq!(check_durable_dirty_usage_replay_bytes(&record), expected);
+        }
+    }
+
+    #[test]
+    #[serial]
+    fn durable_dirty_usage_decoded_replay_rejects_large_values_before_state_changes() {
+        for field in ["epoch", "prefix", "entries"] {
+            clear_dirty_usage_buckets_for_tests();
+            let before = scanner_dirty_usage_state();
+            let mut record = decoded_replay_fixture();
+            match field {
+                "epoch" => record.writer_epoch = "x".repeat(1024 * 1024),
+                "prefix" => {
+                    record.entries[0].scope = ScannerDurableDirtyUsageReplayScope::TopLevelEntries {
+                        entries: BTreeSet::from(["x".repeat(1024 * 1024)]),
+                    };
+                }
+                _ => record.entries = vec![record.entries[0].clone(); SCANNER_DURABLE_DIRTY_USAGE_REPLAY_MAX_BYTES + 1],
+            }
+            assert_eq!(record.replay(), Err(ScannerDurableDirtyUsageReplayError::ByteLimit), "{field}");
+            assert_eq!(scanner_dirty_usage_state(), before);
+            assert!(dirty_usage_buckets_for_tests().is_empty());
+            assert!(dirty_usage_bucket_scopes_for_tests().is_empty());
+            assert!(dirty_usage_producer_identities().is_empty());
+            assert_eq!(DIRTY_USAGE_PRODUCER_COVERAGE.load(Ordering::Acquire), 0);
+        }
+        clear_dirty_usage_buckets_for_tests();
+    }
+
+    #[test]
+    #[serial]
+    fn durable_dirty_usage_decoded_replay_preserves_generation_exhaustion() {
+        clear_dirty_usage_buckets_for_tests();
+        let generation = DIRTY_USAGE_BUCKET_GENERATION.swap(u64::MAX, Ordering::AcqRel);
+        let result = decoded_replay_fixture().replay();
+        DIRTY_USAGE_BUCKET_GENERATION.store(generation, Ordering::Release);
+        assert_eq!(result, Err(ScannerDurableDirtyUsageReplayError::InvalidGeneration));
+        assert!(dirty_usage_buckets_for_tests().is_empty());
+        assert!(dirty_usage_bucket_scopes_for_tests().is_empty());
+        assert!(dirty_usage_producer_identities().is_empty());
+        assert_eq!(DIRTY_USAGE_PRODUCER_COVERAGE.load(Ordering::Acquire), 0);
+        clear_dirty_usage_buckets_for_tests();
+    }
+
     #[test]
     #[serial]
     fn durable_dirty_usage_replay_rejects_invalid_records_without_partial_state() {
@@ -843,9 +1017,17 @@ mod scoped_dirty_usage_tests {
 
         for (bytes, expected_error) in invalid_cases {
             clear_dirty_usage_buckets_for_tests();
-            assert_eq!(replay_durable_dirty_usage_producer_record(&bytes), Err(expected_error));
+            let before = scanner_dirty_usage_state();
+            assert_eq!(replay_durable_dirty_usage_producer_record(&bytes), Err(expected_error.clone()));
             assert!(dirty_usage_buckets_for_tests().is_empty());
             assert!(dirty_usage_bucket_scopes_for_tests().is_empty());
+            let record: ScannerDurableDirtyUsageReplayRecord = serde_json::from_slice(&bytes).expect("typed invalid record");
+            assert_eq!(record.replay(), Err(expected_error));
+            assert_eq!(scanner_dirty_usage_state(), before);
+            assert!(dirty_usage_buckets_for_tests().is_empty());
+            assert!(dirty_usage_bucket_scopes_for_tests().is_empty());
+            assert!(dirty_usage_producer_identities().is_empty());
+            assert_eq!(DIRTY_USAGE_PRODUCER_COVERAGE.load(Ordering::Acquire), 0);
         }
 
         clear_dirty_usage_buckets_for_tests();

crates/scanner/src/scanner_io/io_cache.rs

@@ -1090,7 +1090,7 @@ impl ScannerIOCache for SetDisks {
 
                     // Lock order: scanner leader fence -> set-scoped per-bucket cache lock ->
                     // cache object read/write.
-                    let cache_guard = match acquire_scanner_cache_locks(store_clone_clone.as_ref(), &cache_name, source).await {
+                    let mut cache_guard = match acquire_scanner_cache_locks(store_clone_clone.as_ref(), &cache_name, source).await {
                         Ok(guard) => guard,
                         Err(e) => {
                             if e.is_contention() {
@@ -1320,9 +1320,10 @@ impl ScannerIOCache for SetDisks {
                     );
 
                     let (checkpoint_tx, mut checkpoint_rx) = mpsc::channel::<DataUsageCache>(1);
+                    let (node_tx, mut node_rx) = crate::workload_admission::scanner_node_request_channel();
 
                     let scan_ctx = ctx_clone.child_token();
-                    let scan = disk.clone().nsscanner_disk(
+                    let scan = crate::workload_admission::with_scanner_node_requests(node_tx, disk.clone().nsscanner_disk(
                         scan_ctx.clone(),
                         budget_clone.clone(),
                         set_disk_inventory_clone.as_ref().clone(),
@@ -1333,7 +1334,7 @@ impl ScannerIOCache for SetDisks {
                             prefix_scan_scope,
                             checkpoint_tx: Some(checkpoint_tx),
                         },
-                    );
+                    ));
                     tokio::pin!(scan);
                     let mut lock_watch = tokio::time::interval(SCANNER_CACHE_LOCK_POLL_INTERVAL);
                     lock_watch.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Delay);
@@ -1341,6 +1342,24 @@ impl ScannerIOCache for SetDisks {
                     let scan_result = loop {
                         tokio::select! {
                             result = &mut scan => break result,
+                            request = async {
+                                match node_rx.as_mut() {
+                                    Some(receiver) => receiver.recv().await,
+                                    None => std::future::pending().await,
+                                }
+                            } => {
+                                let Some(request) = request else {
+                                    node_rx = None;
+                                    continue;
+                                };
+                                if let Err(error) = cache_guard.resume_node_operation(
+                                    store_clone_clone.clone(), &cache_name, source, &revisions, request,
+                                ).await {
+                                    scan_ctx.cancel();
+                                    await_scanner_disk_shutdown(scan.as_mut()).await;
+                                    break Err(error);
+                                }
+                            }
                             _ = lock_watch.tick() => {
                                 if cache_guard.is_lock_lost() {
                                     scan_ctx.cancel();

crates/scanner/src/scanner_io/io_disk.rs

@@ -38,6 +38,13 @@ pub(super) fn tier_stats_template(tier_names: &[String]) -> HashMap<String, Tier
     tier_stats
 }
 
+fn ensure_scanner_node_operation_active(cancellation: Option<&CancellationToken>) -> Result<()> {
+    if cancellation.is_some_and(CancellationToken::is_cancelled) {
+        return Err(StorageError::other("Scanner operation cancelled"));
+    }
+    Ok(())
+}
+
 #[async_trait::async_trait]
 impl ScannerIODisk for Disk {
     async fn get_size(&self, item: ScannerItem) -> Result<SizeSummary> {
@@ -45,14 +52,18 @@ impl ScannerIODisk for Disk {
     }
 
     async fn get_size_with_tier_names(&self, mut item: ScannerItem, tier_names: &[String]) -> Result<SizeSummary> {
+        let cancellation = crate::workload_admission::scanner_node_operation_cancellation();
         let done_object = Metrics::time(Metric::ScanObject);
 
         if !is_xl_meta_path(&item.path) {
             return Err(StorageError::other(SCANNER_SKIP_FILE_ERROR.to_string()));
         }
 
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
         let metadata_object_path = item.object_path();
-        let data = match self.read_metadata(&item.bucket, &metadata_object_path).await {
+        let metadata_result = self.read_metadata(&item.bucket, &metadata_object_path).await;
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
+        let data = match metadata_result {
             Ok(data) => data,
             Err(e) if DiskError::is_err_object_not_found(&e) || DiskError::is_err_version_not_found(&e) => {
                 return Err(StorageError::other(SCANNER_SKIP_FILE_ERROR.to_string()));
@@ -86,7 +97,10 @@ impl ScannerIODisk for Disk {
         // (which used to query it a second time). On failure keep the
         // historical fallback: default configuration (versioned = false) plus
         // the warn that `apply_actions` used to emit.
-        let versioning_config = match BucketVersioningSys::get(&item.bucket).await {
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
+        let versioning_result = BucketVersioningSys::get(&item.bucket).await;
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
+        let versioning_config = match versioning_result {
             Ok(versioning_config) => versioning_config,
             Err(_) => {
                 warn!(
@@ -122,7 +136,9 @@ impl ScannerIODisk for Disk {
             ..Default::default()
         };
 
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
         let lock_config = object_lock_config_for_scanner_item(&item).await;
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
 
         // Count every version this object contributes to the scan, independent
         // of any lifecycle configuration, so scan-coverage metrics stay honest
@@ -130,17 +146,33 @@ impl ScannerIODisk for Disk {
         // `object_infos`.
         global_metrics().record_scanner_versions_scanned(object_infos.len() as u64);
 
-        item.apply_actions(object_infos, lock_config, versioning_config, tier_names, &mut size_summary)
-            .await;
+        #[cfg(test)]
+        let _ = crate::scanner_folder::observe_test_size_dispatch_boundary("apply_actions");
+        item.apply_actions_cancellable(
+            object_infos,
+            lock_config,
+            versioning_config,
+            tier_names,
+            &mut size_summary,
+            cancellation.as_ref(),
+        )
+        .await;
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
 
         if !free_version_infos.is_empty() {
             for oi in free_version_infos {
+                ensure_scanner_node_operation_active(cancellation.as_ref())?;
                 if ScannerItem::tier_is_known(&oi, tier_names) {
-                    enqueue_runtime_free_version(oi).await;
+                    #[cfg(test)]
+                    if crate::scanner_folder::observe_test_size_dispatch_boundary("free_version_dispatch") {
+                        continue;
+                    }
+                    enqueue_runtime_free_version(oi, cancellation.as_ref()).await;
                 }
             }
         }
 
+        ensure_scanner_node_operation_active(cancellation.as_ref())?;
         done_object();
 
         Ok(size_summary)

crates/scanner/src/scanner_io/publish_gate_tests.rs

@@ -996,6 +996,73 @@ fn completed_data_usage_info_adds_same_bucket_across_unique_sets() {
     assert_eq!(bucket.delete_markers_count, 1);
 }
 
+#[test]
+fn bucket_usage_incarnation_is_optional_and_old_readers_ignore_it() {
+    #[derive(serde::Deserialize)]
+    struct LegacyBucketUsage {
+        size: u64,
+    }
+    let legacy = BucketUsageInfo {
+        size: 42,
+        ..Default::default()
+    };
+    let without = serde_json::to_value(&legacy).expect("encode legacy usage");
+    assert!(without.get("bucket_incarnation").is_none());
+    let restored: BucketUsageInfo = serde_json::from_value(without).expect("decode old usage");
+    assert_eq!(restored.bucket_incarnation, None);
+    let certified = BucketUsageInfo {
+        size: 42,
+        bucket_incarnation: Some(uuid::Uuid::from_u128(7).to_string()),
+        ..Default::default()
+    };
+    let encoded = serde_json::to_vec(&certified).expect("encode certified usage");
+    let old: LegacyBucketUsage = serde_json::from_slice(&encoded).expect("old schema ignores additive field");
+    assert_eq!(old.size, 42);
+    let named = rmp_serde::to_vec_named(&certified).expect("encode certified named msgpack");
+    let old: LegacyBucketUsage = rmp_serde::from_slice(&named).expect("old named reader ignores additive field");
+    assert_eq!(old.size, 42);
+    let old_bytes = rmp_serde::to_vec_named(&legacy).expect("encode old shape");
+    let new: BucketUsageInfo = rmp_serde::from_slice(&old_bytes).expect("new reader accepts old shape");
+    assert_eq!(new.bucket_incarnation, None);
+}
+
+#[test]
+fn completed_usage_certifies_only_matching_non_nil_bucket_incarnations() {
+    let buckets = vec!["bucket".to_string()];
+    let id = uuid::Uuid::from_u128(7);
+    let mut a = completed_root_cache("bucket", 2, 10, DataUsageCacheSource::new(0, 0));
+    let mut b = completed_root_cache("bucket", 3, 20, DataUsageCacheSource::new(1, 0));
+    a.info.scan_bucket_incarnations.insert("bucket".to_string(), id);
+    b.info.scan_bucket_incarnations.insert("bucket".to_string(), id);
+    let published = completed_data_usage_info_for_test(&[a.clone(), b.clone()], &buckets, false, false)
+        .unwrap()
+        .0;
+    assert_eq!(
+        published.buckets_usage["bucket"].bucket_incarnation.as_deref(),
+        Some(id.to_string().as_str())
+    );
+    let encoded = serde_json::to_vec(&published).expect("serialize certified usage");
+    let decoded: DataUsageInfo = serde_json::from_slice(&encoded).expect("read certified usage");
+    assert_eq!(decoded.buckets_usage["bucket"].bucket_incarnation, Some(id.to_string()));
+    b.info
+        .scan_bucket_incarnations
+        .insert("bucket".to_string(), uuid::Uuid::from_u128(8));
+    let mismatch = completed_data_usage_info_for_test(&[a.clone(), b.clone()], &buckets, false, false)
+        .unwrap()
+        .0;
+    assert_eq!(mismatch.buckets_usage["bucket"].bucket_incarnation, None);
+    b.info.scan_bucket_incarnations.remove("bucket");
+    let missing = completed_data_usage_info_for_test(&[a.clone(), b.clone()], &buckets, false, false)
+        .unwrap()
+        .0;
+    assert_eq!(missing.buckets_usage["bucket"].bucket_incarnation, None);
+    b.info
+        .scan_bucket_incarnations
+        .insert("bucket".to_string(), uuid::Uuid::nil());
+    let nil = completed_data_usage_info_for_test(&[a, b], &buckets, false, false).unwrap().0;
+    assert_eq!(nil.buckets_usage["bucket"].bucket_incarnation, None);
+}
+
 #[test]
 fn checked_bucket_usage_info_moves_replication_keys_and_preserves_the_snapshot() {
     let first_target = "arn:rustfs:replication:local::target-a".to_string();
@@ -1057,6 +1124,7 @@ fn checked_bucket_usage_info_moves_replication_keys_and_preserves_the_snapshot()
     }
     let expected = BucketUsageInfo {
         size: 32768,
+        bucket_incarnation: None,
         replication_pending_size_v1: 0,
         replication_failed_size_v1: 0,
         replicated_size_v1: 0,

crates/scanner/src/scanner_io/tests.rs

@@ -46,7 +46,9 @@ use uuid::Uuid;
 
 mod checkpoint_coverage_identity;
 mod collector_lifecycle;
+mod expiry_lock;
 mod listing_window_scope;
+mod node_admission;
 mod partial_bucket_carry;
 mod per_bucket_certification;
 mod scoped_entry_fallback;

crates/scanner/src/scanner_io/tests/expiry_lock.rs

@@ -0,0 +1,183 @@
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use super::*;
+use crate::storage_api::owner::EcstoreExpiryState;
+use std::future::Future;
+use std::pin::Pin;
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::task::Poll;
+use std::time::Duration;
+
+// Return Some(result) if the operation ended too early, None only if it was
+// actually polled pending after the prerequisite read had finished.
+async fn observe_queued<F: Future>(
+    mut operation: Pin<&mut F>,
+    read_complete: impl Fn() -> bool,
+    observation: Duration,
+) -> std::result::Result<Option<F::Output>, tokio::time::error::Elapsed> {
+    tokio::time::timeout(
+        observation,
+        std::future::poll_fn(|cx| match operation.as_mut().poll(cx) {
+            Poll::Ready(value) => Poll::Ready(Some(value)),
+            Poll::Pending if read_complete() => Poll::Ready(None),
+            Poll::Pending => Poll::Pending,
+        }),
+    )
+    .await
+}
+
+#[tokio::test]
+#[serial]
+async fn free_version_cancelled_while_waiting_for_expiry_write_lock_never_queues() {
+    let state = EcstoreExpiryState::new_with_unconsumed_worker_channel(4);
+    let observation = Duration::from_secs(rustfs_config::DEFAULT_DRIVE_METADATA_TIMEOUT_SECS);
+    let context = crate::ExpiryLockTestContext {
+        state: state.clone(),
+        store: None,
+        completed_incarnation_reads: Arc::new(AtomicUsize::new(0)),
+    };
+    crate::EXPIRY_LOCK_TEST_CONTEXT
+        .scope(context, async {
+            let object = crate::ScannerObjectInfo {
+                bucket: "expiry-lock-bucket".to_string(),
+                name: "free-object".to_string(),
+                ..Default::default()
+            };
+            let cancellation = CancellationToken::new();
+            let guard = state.write().await;
+            let mut pending = Box::pin(crate::enqueue_runtime_free_version(object.clone(), Some(&cancellation)));
+            let first = observe_queued(pending.as_mut(), || true, observation).await;
+            let observed_wait = matches!(&first, Ok(None));
+            let already_finished = matches!(&first, Ok(Some(())));
+            cancellation.cancel();
+            let cancelled_while_locked = if already_finished {
+                false
+            } else {
+                tokio::time::timeout(observation, pending.as_mut()).await.is_ok()
+            };
+            let pending_while_locked = guard.pending_tasks();
+            drop(guard);
+            if !already_finished && !cancelled_while_locked {
+                pending.as_mut().await;
+            }
+            drop(pending);
+            let pending_after_cancel = state.read().await.pending_tasks();
+
+            // Positive control queues a real free-version task while using the same
+            // implementation and isolated, unconsumed worker channel.
+            let mut positive = Box::pin(crate::enqueue_runtime_free_version(object, None));
+            let positive_in_time = tokio::time::timeout(observation, positive.as_mut()).await.is_ok();
+            if !positive_in_time {
+                positive.as_mut().await;
+            }
+            drop(positive);
+            let pending_after_control = state.read().await.pending_tasks();
+            assert!(observed_wait, "must poll the real enqueue while the write lock is held");
+            assert!(cancelled_while_locked, "cancellation must finish before the lock is released");
+            assert_eq!(pending_while_locked, 0);
+            assert_eq!(pending_after_cancel, 0);
+            assert!(positive_in_time, "positive control must finish within the observation limit");
+            assert_eq!(pending_after_control, 1, "positive control must queue a task");
+        })
+        .await;
+}
+
+#[tokio::test]
+#[serial]
+async fn newer_noncurrent_cancelled_after_real_read_while_waiting_for_expiry_write_lock_never_queues() {
+    let (_temp_dir, store) = setup_local_scanner_store(1, 4).await;
+    let bucket = "expiry-lock-bucket";
+    store
+        .make_bucket(bucket, &MakeBucketOptions::default())
+        .await
+        .expect("create bucket");
+    let expected_incarnation = store.bucket_incarnation_id(bucket).await.expect("real incarnation metadata");
+    assert!(!expected_incarnation.is_nil());
+    let state = EcstoreExpiryState::new_with_unconsumed_worker_channel(4);
+    let reads = Arc::new(AtomicUsize::new(0));
+    let context = crate::ExpiryLockTestContext {
+        state: state.clone(),
+        store: Some(store.clone()),
+        completed_incarnation_reads: reads.clone(),
+    };
+    let observation = Duration::from_secs(rustfs_config::DEFAULT_DRIVE_METADATA_TIMEOUT_SECS);
+    crate::EXPIRY_LOCK_TEST_CONTEXT
+        .scope(context, async {
+            let versions = vec![crate::ScannerObjectToDelete {
+                object_name: "noncurrent-object".to_string(),
+                version_id: Some(Uuid::new_v4()),
+                ..Default::default()
+            }];
+            let event = crate::Event::default();
+            let src = crate::LcEventSrc::Scanner;
+            let cancellation = CancellationToken::new();
+            let guard = state.write().await;
+            let mut pending = Box::pin(crate::enqueue_runtime_newer_noncurrent(
+                bucket,
+                versions.clone(),
+                event.clone(),
+                &src,
+                Some(&cancellation),
+            ));
+            let first = observe_queued(pending.as_mut(), || reads.load(Ordering::SeqCst) == 1, observation).await;
+            let observed_wait_after_read = matches!(&first, Ok(None));
+            let mut result = match first {
+                Ok(Some(value)) => Some(value),
+                _ => None,
+            };
+            cancellation.cancel();
+            let cancelled_while_locked = if result.is_some() {
+                false
+            } else {
+                match tokio::time::timeout(observation, pending.as_mut()).await {
+                    Ok(value) => {
+                        result = Some(value);
+                        true
+                    }
+                    Err(_) => false,
+                }
+            };
+            let pending_while_locked = guard.pending_tasks();
+            drop(guard);
+            let result = match result {
+                Some(value) => value,
+                None => pending.as_mut().await,
+            };
+            drop(pending);
+            let pending_after_cancel = state.read().await.pending_tasks();
+            let mut positive = Box::pin(crate::enqueue_runtime_newer_noncurrent(bucket, versions, event, &src, None));
+            let bounded_positive = tokio::time::timeout(observation, positive.as_mut()).await;
+            let positive_in_time = bounded_positive.is_ok();
+            let positive_result = match bounded_positive {
+                Ok(value) => value,
+                Err(_) => positive.as_mut().await,
+            };
+            drop(positive);
+            let pending_after_control = state.read().await.pending_tasks();
+            assert!(
+                observed_wait_after_read,
+                "real incarnation read must finish before waiting on the held lock"
+            );
+            assert!(cancelled_while_locked, "cancellation must finish before the lock is released");
+            assert!(!result);
+            assert_eq!(pending_while_locked, 0);
+            assert_eq!(pending_after_cancel, 0);
+            assert!(positive_in_time, "positive control must finish within the observation limit");
+            assert!(positive_result, "positive control must enqueue the nonempty version batch");
+            assert_eq!(pending_after_control, 1);
+            assert_eq!(reads.load(Ordering::SeqCst), 2);
+        })
+        .await;
+}

crates/scanner/src/scanner_io/tests/node_admission.rs

@@ -0,0 +1,136 @@
+// Copyright 2026 RustFS Team
+// Licensed under the Apache License, Version 2.0.
+
+use super::*;
+use crate::workload_admission::ScannerNodeRequest;
+use rustfs_concurrency::adaptive::{FeedbackController, FeedbackObservation, NodeAdmission, ResourcePressure};
+use std::num::NonZeroU16;
+use tokio::sync::oneshot;
+
+#[derive(Clone, Copy, PartialEq, Eq)]
+enum ResumeCase {
+    Unchanged,
+    Updated,
+    Cancelled,
+}
+
+async fn check_cache_lease_resume(case: ResumeCase) {
+    let (_directory, store) = setup_local_scanner_store(1, 4).await;
+    let set = store.pools[0].disk_set[0].clone();
+    let source = DataUsageCacheSource::new(0, 0);
+    let cache_name = "node-resume/.usage-cache.bin";
+    let cache = DataUsageCache::default();
+    cache.save(set.clone(), cache_name).await.expect("seed cache");
+    let revisions = DataUsageCache::read_revisions(set.clone(), cache_name)
+        .await
+        .expect("initial revisions");
+    let gate = NodeAdmission::new(NonZeroU16::new(1).expect("one shared unit"));
+    gate.update(
+        &mut FeedbackController::new(),
+        Some(FeedbackObservation {
+            generation: 1,
+            max_concurrency: 1,
+            pressure: ResourcePressure::Unknown,
+            completed_units: None,
+        }),
+    );
+    let mut held = Some(gate.acquire().await);
+    let mut guard = acquire_scanner_cache_locks(set.as_ref(), cache_name, source)
+        .await
+        .expect("initial cache lease");
+    let ctx = CancellationToken::new();
+    let (respond, response) = oneshot::channel();
+    let request = ScannerNodeRequest {
+        owner: gate.clone(),
+        respond,
+        cancel: ctx.clone(),
+    };
+    let mut expected = revisions.clone();
+    let result = {
+        let resume = guard.resume_node_operation(set.clone(), cache_name, source, &revisions, request);
+        tokio::pin!(resume);
+        assert!(futures::poll!(&mut resume).is_pending(), "shared node is occupied");
+        let other = tokio::time::timeout(Duration::from_secs(1), acquire_scanner_cache_locks(set.as_ref(), cache_name, source))
+            .await
+            .expect("cache lock must be released before joining the node queue")
+            .expect("another cache worker can acquire the lease");
+        if case == ResumeCase::Updated {
+            let mut newer = cache;
+            newer.info.next_cycle = 1;
+            newer
+                .save(set.clone(), cache_name)
+                .await
+                .expect("another worker updates the cache");
+            expected = DataUsageCache::read_revisions(set.clone(), cache_name)
+                .await
+                .expect("new cache revisions");
+            assert_ne!(expected, revisions);
+        }
+        drop(other);
+        if case == ResumeCase::Cancelled {
+            ctx.cancel();
+        } else {
+            held.take().expect("held node unit").complete();
+        }
+        tokio::time::timeout(Duration::from_secs(2), resume)
+            .await
+            .expect("node resumption must finish or observe cancellation")
+    };
+    if case == ResumeCase::Unchanged {
+        result.expect("unchanged cache resumes the same walk");
+        let permit = response.await.expect("coordinator returns the node permit");
+        assert_eq!(gate.snapshot().active, 1);
+        assert_eq!(gate.completed(), Some(1), "admitting scanner work must not count it as completed");
+        assert!(!guard.is_lock_lost());
+        let lock = set
+            .new_ns_lock(RUSTFS_META_BUCKET, &scanner_cache_lock_resource(cache_name, source))
+            .await
+            .expect("competing cache lock");
+        assert!(
+            lock.get_write_lock_quiet(Duration::from_millis(20)).await.is_err(),
+            "cache lease must be restored before the operation resumes"
+        );
+        permit.complete();
+    } else {
+        result.expect_err("cancelled or stale work cannot resume");
+        assert!(response.await.is_err(), "failed resumption must not authorize storage work");
+        if case == ResumeCase::Cancelled {
+            assert!(guard.is_lock_lost());
+            assert_eq!(gate.snapshot().active, 1, "the running heal keeps its unit");
+            drop(held.take());
+            assert_eq!(gate.completed(), Some(0));
+        } else {
+            assert_eq!(gate.completed(), Some(1));
+        }
+    }
+    drop(guard);
+    assert_eq!(gate.snapshot().active, 0);
+    assert!(gate.try_acquire().is_some(), "dropped requests must leave no queue or capacity leak");
+    assert_eq!(
+        DataUsageCache::read_revisions(set.clone(), cache_name)
+            .await
+            .expect("final revisions"),
+        expected
+    );
+    acquire_scanner_cache_locks(set.as_ref(), cache_name, source)
+        .await
+        .expect("final cache lease is available");
+}
+
+#[tokio::test]
+#[serial]
+async fn scanner_node_wait_yields_cache_lease_before_fifo_admission() {
+    check_cache_lease_resume(ResumeCase::Unchanged).await;
+}
+
+#[tokio::test]
+#[serial]
+async fn scanner_node_wait_rejects_cache_changed_while_unlocked() {
+    check_cache_lease_resume(ResumeCase::Updated).await;
+}
+
+#[tokio::test]
+#[serial]
+async fn scanner_node_wait_cancellation_releases_queue_without_stealing_running_unit() {
+    check_cache_lease_resume(ResumeCase::Cancelled).await;
+}

crates/scanner/src/storage_api.rs

@@ -22,6 +22,8 @@ use serde::{Deserialize, Serialize};
 use tokio::sync::Notify;
 
 pub(crate) use rustfs_ecstore::with_background_disk_io as ecstore_with_background_disk_io;
+#[cfg(all(test, unix))]
+pub(crate) use rustfs_ecstore::with_background_resource_unit as ecstore_with_background_resource_unit;
 
 pub(crate) use s3s::dto::{
     BucketLifecycleConfiguration as EcstoreBucketLifecycleConfiguration, LifecycleRuleFilter as EcstoreLifecycleRuleFilter,
@@ -39,6 +41,8 @@ pub(crate) use rustfs_ecstore::api::data_usage::{NativeScannerPauseBacklogWriteF
 
 pub(crate) use rustfs_ecstore::api::bucket::bucket_target_sys::BucketTargetSys as EcstoreBucketTargetSys;
 pub(crate) use rustfs_ecstore::api::bucket::lifecycle::bucket_lifecycle_audit::LcEventSrc as EcstoreLcEventSrc;
+#[cfg(test)]
+pub(crate) use rustfs_ecstore::api::bucket::lifecycle::bucket_lifecycle_ops::ExpiryState as EcstoreExpiryState;
 pub(crate) use rustfs_ecstore::api::bucket::lifecycle::bucket_lifecycle_ops::{
     apply_expiry_rule as ecstore_apply_expiry_rule, apply_transition_rule as ecstore_apply_transition_rule,
     lifecycle_version_delete_target as ecstore_lifecycle_version_delete_target,
@@ -99,6 +103,10 @@ pub(crate) use rustfs_ecstore::api::disk::{
 pub(crate) use rustfs_ecstore::api::disk::{
     DiskOption as EcstoreDiskOption, DiskStore as EcstoreDiskStore, new_disk as ecstore_new_disk,
 };
+#[cfg(all(test, unix))]
+pub(crate) use rustfs_ecstore::api::disk::{
+    LocalPublicationPause as EcstoreLocalPublicationPause, LocalPublicationStage as EcstoreLocalPublicationStage,
+};
 pub(crate) use rustfs_ecstore::api::error::{
     Error as EcstoreErrorType, Result as EcstoreResultType, StorageError as EcstoreStorageError,
 };
@@ -161,10 +169,17 @@ pub(crate) mod ecstore_diagnostic {
 pub(crate) type EcstoreHealResultItem = <EcstoreStore as storage_contracts::HealOperations>::HealResultItem;
 
 pub(crate) mod owner {
+    #[cfg(test)]
+    pub(crate) use super::EcstoreExpiryState;
     #[cfg(test)]
     pub(crate) use super::ecstore_set_object_store_resolver;
     #[cfg(test)]
     pub(crate) use super::storage_contracts::DiskSetSelector;
+    #[cfg(all(test, unix))]
+    pub(crate) use super::{
+        EcstoreLocalPublicationPause, EcstoreLocalPublicationStage, ecstore_with_background_disk_io,
+        ecstore_with_background_resource_unit,
+    };
     pub(crate) use super::{
         MAX_SCANNER_PAUSE_BACKLOG_BYTES, ScannerPauseBacklogRetirementError, ScannerPauseBacklogRetirementPlan,
         ScannerPauseBacklogRetirementReplica, register_scanner_pause_backlog_retirement_planner,

crates/scanner/src/workload_admission.rs

@@ -12,9 +12,143 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use std::sync::{Arc, LazyLock, RwLock};
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{Arc, LazyLock, OnceLock, RwLock};
 
+use rustfs_concurrency::adaptive::{NodeAdmission, NodePermit};
 use rustfs_concurrency::{AdmissionState, WorkloadAdmissionRegistrySnapshot, WorkloadAdmissionSnapshotProvider, WorkloadClass};
+use tokio::sync::{mpsc, oneshot};
+use tokio_util::sync::CancellationToken;
+
+use crate::ScannerError;
+
+static SCANNER_NODE_ADMISSION: OnceLock<Arc<NodeAdmission>> = OnceLock::new();
+
+tokio::task_local! {
+    static SCANNER_NODE_REQUESTS: ScannerNodeRequestSender;
+    static SCANNER_NODE_OPERATION_CANCEL: CancellationToken;
+}
+
+/// Cancellation for the currently admitted scanner operation, when present.
+pub(crate) fn scanner_node_operation_cancellation() -> Option<CancellationToken> {
+    SCANNER_NODE_OPERATION_CANCEL.try_with(Clone::clone).ok()
+}
+
+pub(crate) struct ScannerNodeRequest {
+    pub(crate) owner: Arc<NodeAdmission>,
+    pub(crate) respond: oneshot::Sender<NodePermit>,
+    pub(crate) cancel: CancellationToken,
+}
+
+pub(crate) type ScannerNodeRequestSender = mpsc::Sender<ScannerNodeRequest>;
+pub(crate) type ScannerNodeRequestReceiver = mpsc::Receiver<ScannerNodeRequest>;
+
+/// One suspended operation per walk; disabled admission allocates no channel.
+pub(crate) fn scanner_node_request_channel() -> (Option<ScannerNodeRequestSender>, Option<ScannerNodeRequestReceiver>) {
+    if scanner_node_admission().is_none() {
+        return (None, None);
+    }
+    let (sender, receiver) = mpsc::channel(1);
+    (Some(sender), Some(receiver))
+}
+
+pub(crate) async fn with_scanner_node_requests<F: std::future::Future>(
+    sender: Option<ScannerNodeRequestSender>,
+    operation: F,
+) -> F::Output {
+    match sender {
+        Some(sender) => SCANNER_NODE_REQUESTS.scope(sender, operation).await,
+        None => operation.await,
+    }
+}
+
+#[cfg(test)]
+tokio::task_local! {
+    pub(crate) static TEST_SCANNER_NODE_ADMISSION: Arc<NodeAdmission>;
+    pub(crate) static TEST_SCANNER_AFTER_NODE_ACQUIRE: Arc<dyn Fn() + Send + Sync>;
+}
+
+/// Install the heal manager's node owner before starting scanner workers.
+/// Refuse replacement: existing scans must not outlive an independently renewed owner.
+pub fn set_scanner_node_admission(owner: Arc<NodeAdmission>) -> bool {
+    SCANNER_NODE_ADMISSION.set(owner).is_ok()
+}
+
+pub(crate) fn scanner_node_admission() -> Option<Arc<NodeAdmission>> {
+    #[cfg(test)]
+    if let Ok(owner) = TEST_SCANNER_NODE_ADMISSION.try_with(Arc::clone) {
+        return Some(owner);
+    }
+    SCANNER_NODE_ADMISSION.get().cloned()
+}
+
+/// Try the fast path first. A scoped coordinator releases the cache lease before
+/// joining the node queue and validates the cache before returning a permit.
+/// Uncoordinated callers defer instead of parking under an unknown lock.
+pub(crate) async fn run_scanner_node_operation<T, E>(
+    owner: Option<&Arc<NodeAdmission>>,
+    cancel: &CancellationToken,
+    operation: impl std::future::Future<Output = Result<T, E>>,
+) -> Result<Result<T, E>, ScannerError> {
+    let Some(owner) = owner else {
+        return Ok(operation.await);
+    };
+    let operation = SCANNER_NODE_OPERATION_CANCEL.scope(cancel.clone(), operation);
+    if cancel.is_cancelled() {
+        return Err(ScannerError::Other("Operation cancelled".to_string()));
+    }
+    let permit = match owner.try_acquire() {
+        Some(permit) => permit,
+        None => {
+            let sender = SCANNER_NODE_REQUESTS
+                .try_with(Clone::clone)
+                .map_err(|_| ScannerError::ResourceDeferred)?;
+            let acquire = async {
+                let (respond, response) = oneshot::channel();
+                sender
+                    .send(ScannerNodeRequest {
+                        owner: owner.clone(),
+                        respond,
+                        cancel: cancel.clone(),
+                    })
+                    .await
+                    .map_err(|_| ScannerError::ResourceDeferred)?;
+                response.await.map_err(|_| ScannerError::ResourceDeferred)
+            };
+            tokio::select! {
+                biased;
+                _ = cancel.cancelled() => return Err(ScannerError::Other("Operation cancelled".to_string())),
+                permit = acquire => permit?,
+            }
+        }
+    };
+    #[cfg(test)]
+    let _ = TEST_SCANNER_AFTER_NODE_ACQUIRE.try_with(|hook| hook());
+    let operation_started = AtomicBool::new(false);
+    tokio::pin!(operation);
+    let observed = std::future::poll_fn(|context| {
+        operation_started.store(true, Ordering::Relaxed);
+        std::future::Future::poll(operation.as_mut(), context)
+    });
+    tokio::pin!(observed);
+    let result = tokio::select! {
+        biased;
+        _ = cancel.cancelled() => {
+            // The node slot belongs to the waiter, not the native operation.
+            drop(permit);
+            if !operation_started.load(Ordering::Relaxed) {
+                return Err(ScannerError::Other("Operation cancelled".to_string()));
+            }
+            // Keep polling the started operation under its existing locks.
+            return Ok(observed.await);
+        }
+        result = &mut observed => result,
+    };
+    if result.is_ok() && !cancel.is_cancelled() {
+        permit.complete();
+    }
+    Ok(result)
+}
 
 type WorkloadSnapshotProviderRef = Arc<dyn WorkloadAdmissionSnapshotProvider + Send + Sync>;
 

crates/targets/src/runtime/mod.rs

@@ -1471,6 +1471,7 @@ mod tests {
             inner: QueueStore<QueuedPayload>,
             fail_put_failed_raw: Arc<std::sync::atomic::AtomicBool>,
             fail_del: Arc<std::sync::atomic::AtomicBool>,
+            delete_attempts: Arc<Semaphore>,
         }
 
         impl Store<QueuedPayload> for FailingFailedStore {
@@ -1499,10 +1500,13 @@ mod tests {
                 self.inner.get_raw(key)
             }
             fn del(&self, key: &Self::Key) -> Result<(), Self::Error> {
-                if self.fail_del.load(Ordering::SeqCst) {
-                    return Err(StoreError::Internal("injected del failure".to_string()));
-                }
-                self.inner.del(key)
+                let result = if self.fail_del.load(Ordering::SeqCst) {
+                    Err(StoreError::Internal("injected del failure".to_string()))
+                } else {
+                    self.inner.del(key)
+                };
+                self.delete_attempts.add_permits(1);
+                result
             }
             fn delete(&self) -> Result<(), Self::Error> {
                 self.inner.delete()
@@ -1986,6 +1990,7 @@ mod tests {
                 inner: inner.clone(),
                 fail_put_failed_raw: fail_flag.clone(),
                 fail_del: Arc::new(std::sync::atomic::AtomicBool::new(false)),
+                delete_attempts: Arc::new(Semaphore::new(0)),
             };
             // The target's terminal move writes through the rejecting failed handle, so the injected
             // failure is what the move hits.
@@ -2042,6 +2047,7 @@ mod tests {
                 inner: inner.clone(),
                 fail_put_failed_raw: Arc::new(std::sync::atomic::AtomicBool::new(false)),
                 fail_del: Arc::new(std::sync::atomic::AtomicBool::new(true)),
+                delete_attempts: Arc::new(Semaphore::new(0)),
             };
             let target = Arc::new(ProgrammedTarget::new(
                 Some(TargetError::JetStreamPublish {
@@ -2053,8 +2059,15 @@ mod tests {
             let tally = Arc::new(ReplayTally::default());
             let (cancel_tx, worker) = spawn_failing_store_worker(&store, target, tally.clone());
 
-            // Many scans run while the live delete keeps failing.
-            tokio::time::sleep(Duration::from_secs(300)).await;
+            // Observe repeated durable overwrites without auto-advancing through thousands of
+            // real filesystem writes. Keep the original virtual observation bound on progress.
+            tokio::time::timeout(Duration::from_secs(300), store.delete_attempts.acquire_many(8))
+                .await
+                .expect("replay should retry the failing delete eight times")
+                .expect("delete progress remains open")
+                .forget();
+            cancel_tx.send(()).await.expect("replay worker should remain cancellable");
+            worker.await.expect("replay worker should drain after cancellation");
             assert_eq!(
                 tally.permanent_failure.load(Ordering::SeqCst),
                 0,
@@ -2063,8 +2076,6 @@ mod tests {
             assert_eq!(inner.len(), 1, "the live entry stays for the next scan");
             assert_eq!(inner.failed_len(), 1, "the durable failed copy landed exactly once");
 
-            let _ = cancel_tx.send(()).await;
-            let _ = worker.await;
             let _ = inner.delete();
         }
 
@@ -2084,6 +2095,7 @@ mod tests {
                 inner: store.clone(),
                 fail_put_failed_raw: Arc::new(std::sync::atomic::AtomicBool::new(false)),
                 fail_del: Arc::new(std::sync::atomic::AtomicBool::new(false)),
+                delete_attempts: Arc::new(Semaphore::new(0)),
             };
             let target = Arc::new(ProgrammedTarget::new(
                 Some(TargetError::JetStreamPublish {

docs/architecture/README.md

@@ -50,6 +50,7 @@ Required headings and strings in these files are asserted by `scripts/check_arch
 | [scanner-usage-authority-decision.md](scanner-usage-authority-decision.md) | deciding whether quota admission depends on scanner data usage, removing scanner publication layers, or designing a scanner storage boundary |
 | [scanner-per-bucket-convergence.md](scanner-per-bucket-convergence.md) | changing what makes a scanner cycle `Complete`, `Superseded`, or converged, adding or re-classifying a dirty-usage producer, deciding whether a background writeback may invalidate a cycle, changing scanner worker concurrency or throttling, or activating scoped dirty acknowledgements |
 | [config-model-boundary-adr.md](config-model-boundary-adr.md) | touching the server-config model (`Config`, `KV`, `KVS`) or its persistence, or asking which crate owns which part of server configuration |
+| [plugin-delegation.md](plugin-delegation.md) | changing original-user plugin delegation, attempt credentials, or Runner task APIs |
 | [admin-route-action-snapshot.md](admin-route-action-snapshot.md) | adding, moving, or re-authorizing an admin route and needing to know where the route → handler → `AdminAction` contract is enforced |
 | [kms-bulk-rekey-contract.md](kms-bulk-rekey-contract.md) | changing the bulk envelope re-wrap sweep, its admin endpoints, the re-wrap primitive, or which objects a rekey may touch |
 | [remote-credential-sealing-adr.md](remote-credential-sealing-adr.md) | adding, reading, or persisting a stored remote credential (replication target, remote tier, on-demand migration source), or needing the sealed-envelope format, the mixed-version rules, or the reason this is worth doing in one deployment and not in another |

docs/architecture/erasure-coding.md

@@ -313,7 +313,7 @@ Small objects store their payload inline after the container CRC ([filemeta_inli
 ## 8. Read path and read quorum
 
 - **INVARIANT — read quorum = `data_blocks`.** `object_quorum_from_meta` returns `(read_quorum = data_blocks, write_quorum)` ([set_disk/metadata.rs](../../crates/ecstore/src/set_disk/metadata.rs)); `parity_blocks = common_parity(...)` is the parity value held by the most disks that still reaches its own read quorum. When `default_parity_count == 0`, read = write = all shards.
-- Authoritative FileInfo selection — `find_file_info_in_quorum` ([set_disk/metadata.rs](../../crates/ecstore/src/set_disk/metadata.rs)) groups valid metas by a content-identity SHA-256 (`file_info_quorum_hash`) that hashes size/flags/mod_time/transition/version_id/data_dir/parts and, for real objects, data/parity/distribution — **excluding replication-status keys** so replication noise never splits quorum. A meta counts only if its mod_time equals the common mod_time (or etag matches when mod_time is absent). The winning hash must reach quorum, else `ErasureReadQuorum`. S3 reads select at read quorum through `select_valid_fileinfo`, the same rule heal uses and MinIO's `getObjectFileInfo`: the most common mod_time wins and a tie goes to the newer one, so a write that failed after reaching exactly `data_blocks` copies is served as listing shows it, instead of `ErasureReadQuorum` until heal runs. Two identities tied at the selected mod_time (a data = parity set split in half, such as a metadata update that failed after reaching half the drives) resolve to the one on the lowest-index disk, in reads and heal alike, so a retried metadata write can repair the split. A selected version with local shards also needs as many copies as its own `data_blocks`, since delete markers and empty versions can lower the common parity's read quorum. A metadata update whose target disks cannot reach write quorum is refused before any write. A version replaced by a committed write keeps fewer than `data_blocks` copies and can never be selected again; the newer side of a failed write can be served and then lose to the older side if one of its disks fails before heal converges the set. Reads in the system bucket (`is_meta_bucketname`) keep the commit-proof rule in `select_committed_fileinfo`: when enough copies answer to prove write quorum, the latest version must hold it, and a degraded read never serves a newer version below write quorum. Pool metadata's PREPARE/COMMIT recovery and identity epochs rely on an ordinary read implying a committed record, so a split stays unreadable until native recovery resolves it. When every drive answered and an S3 latest read still cannot select a version, `read_latest_past_dangling_versions` walks the version stack newest first through exact-version reads, as MinIO's `pickLatestQuorumFilesInfo` resolves stacks: it serves the readable version with the newest selected mod_time, skips versions whose exact read proves them dangling (the NoSuchVersion an explicit GET reports) and queues heal for them, and keeps the read-quorum error on any other outcome. A failed versioned PUT that left the new version on fewer drives than its data blocks therefore no longer hides the committed version below it; ListObjectVersions can still show the dangling version as latest until heal removes it.
+- Authoritative FileInfo selection — `find_file_info_in_quorum` ([set_disk/metadata.rs](../../crates/ecstore/src/set_disk/metadata.rs)) groups valid metas by a content-identity SHA-256 (`file_info_quorum_hash`) that hashes size/flags/mod_time/transition/version_id/data_dir/parts and, for real objects, data/parity/distribution — **excluding replication-status keys** so replication noise never splits quorum. A meta counts only if its mod_time equals the common mod_time (or etag matches when mod_time is absent). The winning hash must reach quorum, else `ErasureReadQuorum`. S3 reads select at read quorum through `select_valid_fileinfo`, the same rule heal uses and MinIO's `getObjectFileInfo`: the most common mod_time wins and a tie goes to the newer one, so a write that failed after reaching exactly `data_blocks` copies is served as listing shows it, instead of `ErasureReadQuorum` until heal runs. Two identities tied at the selected mod_time (a data = parity set split in half, such as a metadata update that failed after reaching half the drives) resolve to the one on the lowest-index disk, in reads and heal alike, so a retried metadata write can repair the split. A selected version with local shards also needs as many copies as its own `data_blocks`, since delete markers and empty versions can lower the common parity's read quorum. A metadata update whose target disks cannot reach write quorum is refused before any write. A version replaced by a committed write keeps fewer than `data_blocks` copies and can never be selected again; the newer side of a failed write can be served and then lose to the older side if one of its disks fails before heal converges the set. Reads in the system bucket (`is_meta_bucketname`) keep the commit-proof rule in `select_committed_fileinfo`: when enough copies answer to prove write quorum, the latest version must hold it, and a degraded read never serves a newer version below write quorum. Pool metadata's PREPARE/COMMIT recovery and identity epochs rely on an ordinary read implying a committed record, so a split stays unreadable until native recovery resolves it. When every drive answered and an S3 latest read still cannot select a version, `read_latest_past_dangling_versions` walks the version stack newest first through exact-version reads, as MinIO's `pickLatestQuorumFilesInfo` resolves stacks: it serves the readable version with the newest selected mod_time, skips versions whose exact read proves them dangling (the NoSuchVersion an explicit GET reports) and queues heal for them, and keeps the read-quorum error on any other outcome. A failed versioned PUT that left the new version on fewer drives than its data blocks therefore no longer hides the committed version below it; ListObjectVersions can still show the dangling version as latest until heal removes it. Metadata updates of the latest version (object tagging, `put_object_metadata`) and the CopyObject source read resolve a failed selection through the same walk; when the walk finds no readable version, tagging keeps the read-quorum error while `put_object_metadata` and CopyObject keep their existing `delete_if_dangling` cleanup. Replication status write-back never walks. The update targets only the served version's disks and is refused before writing when they cannot reach its write quorum, including a version-only copy.
 - **INVARIANT — decode needs ≥ `data_blocks` shards.** The stripe reader requires `available_shards ≥ data_shards`; below that the read fails closed with a read-quorum error (never silent truncation) ([set_disk/read.rs](../../crates/ecstore/src/set_disk/read.rs), [set_disk/shard_source.rs](../../crates/ecstore/src/set_disk/shard_source.rs)). Codec geometry is validated at construction: `Erasure::try_new` / `try_new_with_options` ([erasure.rs](../../crates/ecstore/src/erasure/coding/erasure.rs)) return `ErasureConstructionError` for `data_shards == 0`, `block_size == 0`, shard-count overflow, or an unsupported shard configuration, so a read never reaches a `block_size` / `data_shards` division with invalid geometry (§13).
 - If `available ≥ data_blocks` but some shards are missing, the read is served **and** a background read-repair heal is enqueued.
 - **INVARIANT — cross-stripe read verification.** When a data shard is missing and `available > data_blocks`, reconstruction regenerates parity and compares it to the surviving parity; a mismatch is `InvalidData "inconsistent read source shards"` (backlog#832), catching corruption that passed per-shard bitrot but disagrees across the stripe ([erasure.rs](../../crates/ecstore/src/erasure/coding/erasure.rs)).

docs/architecture/plugin-delegation.md

@@ -0,0 +1,142 @@
+# Plugin delegation
+
+**Use this when:** changing plugin delegation registration, revocation, broker identity, or the scope of attempt credentials.
+
+## Integration boundary
+
+Runner owns scheduling, leases, container execution and result publication. RustFS provides original-user delegation, scoped temporary credentials and authenticated task API forwarding. Inputs and outputs use ordinary versioned S3 buckets; event-driven jobs use the existing bucket notification/Webhook path. Managed artifact sealing, inventory, garbage collection and backup retention require separate storage contracts and are outside this integration.
+
+Set `RUSTFS_PLUGIN_RUNNER_URL` to the Controller HTTPS URL ending in `/v1/ingress/manual/jobs`, and `RUSTFS_PLUGIN_RUNNER_DEPLOYMENT` to the delegation deployment. Forwarding requires the published outbound mTLS client identity and uses the published trust roots when configured. Connections are reused within a TLS generation; publishing new TLS material replaces the pool, and removing the client identity rejects new forwarding requests.
+
+## Authority
+
+A delegation is an immutable restriction record owned by an ordinary IAM user. It is neither a permission grant nor a credential. Creating it requires that user's real signed request and `admin:CreatePluginDelegation`; reading and revoking require the corresponding `admin:GetPluginDelegation` and `admin:RevokePluginDelegation` actions. Root, temporary credentials and service accounts cannot own records.
+
+The record binds a deployment, an input bucket, literal input and output prefixes, and an expiry of at most 24 hours. The v1 profile writes to that same bucket; v2 explicitly names the output bucket. Wildcards, control characters and IAM variable expressions are rejected. Its random ID is also its immutable revision. There is no update operation.
+
+The Controller is responsible for validating accepted task identity, current lease, epoch, node session and control generation before requesting credentials. RustFS authenticates the configured broker and enforces the delegation and current parent IAM. RustFS does not independently verify a remote Controller lease.
+
+```mermaid
+sequenceDiagram
+    participant U as Original IAM user
+    participant C as Controller broker
+    participant R as RustFS
+    participant P as Plugin
+    U->>R: Signed delegation registration
+    R-->>U: Immutable ID and revision
+    C->>C: Validate task and current lease
+    C->>R: Signed issue-attempt request
+    R->>R: Broker mapping + active record + current IAM
+    R->>R: Persist scoped STS and recheck authority
+    R-->>C: Short-lived credentials
+    C-->>P: Attempt credentials
+    P->>R: Exact version GET / attempt-prefix PUT
+    R->>R: Current parent IAM intersected with session policy
+```
+
+## Persistence and revocation
+
+`crates/iam/src/delegation.rs` owns record validation and immutable revocation tombstones. Records use the existing IAM store under `config/iam/plugin-delegations/v1`. Writes require a successful readback. Revocation is idempotent and durable; it does not delete or overwrite the restriction record.
+
+`ObjectStore::load_iam_config_strict` distinguishes a missing object from an empty object, invalid JSON or failed decryption. Only a genuinely absent tombstone permits an active record. Corrupt or unavailable storage rejects access rather than treating revocation as absent. Existing non-delegation readers keep their compatibility behavior.
+
+Revocation prevents future issuance. It does not promise immediate invalidation of credentials already delivered; those remain subject to their expiration and current parent IAM. Registration, IAM changes and issuance are not one atomic transaction. Issuance rechecks after persistence and deletes the generated STS account if authority changed. Failed persistence or invalidation acknowledgment is reported as unknown issuance, never as safe retry permission.
+
+Manual job submission reads the active delegation before calling the Runner. A submission that passed this check is in flight and may be admitted if revocation races with the outbound request; revocation prevents submissions whose authority check occurs afterward, but does not cancel an admitted job. Callers must treat a successful submit receipt as accepted work even if the delegation is revoked later. After an ambiguous timeout or service error, retry the same idempotency key while the delegation remains active; after revocation or expiry, query status instead of retrying submission.
+
+`POST /rustfs/admin/v3/plugin-delegations/{id}/runs/query` accepts `{version:1,run_id}` and requires an ordinary IAM user with `admin:GetPluginRun` who owns the delegation in `{id}`. It reads the immutable owner record without checking expiry or revocation, then queries Runner using the record's delegation ID and revision and the authenticated access key. The result can contain only that caller's run status and committed manifest; it does not perform object reads or reauthorize object access. The Runner response must match the requested run ID and the strict status schema before RustFS returns it.
+
+`POST /rustfs/admin/v3/plugin-delegations/{id}/runs/cancel` accepts the same request and requires `admin:CancelPluginRun` plus ownership of `{id}`. Expiry and revocation do not block cancelling an existing run. Runner scopes the run to that owner; missing and other-owner runs share the same not-found response, while successful and failed runs return conflict. Success returns `{version:1,run_id,state:"CANCELLED",cleanup_pending}` and does not imply that asynchronous cleanup has finished.
+
+`POST /rustfs/admin/v3/plugin-delegations/{id}/runs/page` accepts `{version:1,limit,cursor?}` with a limit from 1 to 100 and requires `admin:ListPluginRuns` plus ownership of `{id}`. Expiry and revocation do not hide historical runs. RustFS supplies signer and delegation identity from authenticated IAM state; the Runner page is scoped to the exact caller and deployment. The strict response contains run summaries and an opaque-to-clients stable cursor; callers pass the returned cursor unchanged until it is null. RustFS bounds request/response sizes and rejects malformed, unordered, over-limit, or identity-invalid summaries.
+
+`POST /rustfs/admin/v3/plugin-delegations/{id}/runs/history` accepts `{version:1,run_id}` and requires `admin:ListPluginRuns` plus ownership of `{id}`. RustFS derives signer and delegation identity from the authenticated user and IAM record, then proxies Runner's bounded history response. The response contains at most the latest 32 committed state events in Runner's history-ID order and a `has_older` flag; timestamps are display data and are not used to reorder events. Missing and foreign runs share the same not-found response. RustFS rejects malformed, empty, over-limit, unexpected-state, or mismatched-run responses and bounds both request and response bodies.
+
+`POST /rustfs/admin/v3/plugin-delegations/{id}/runs/replay` accepts `{version:1,origin_run_id,idempotency_key,deadline_unix_micros}` and requires `admin:ReplayPluginRun`, current IAM authorization, ownership, and an active unexpired delegation. Caller identity fields are not accepted; RustFS derives signer and delegation revision from the authenticated request and IAM record. Runner accepts only an owned failed origin, preserves its fixed plugin/configuration/input version, and requires a new deadline no later than its configured run timeout. RustFS requires a positive Unix-microsecond deadline and verifies the strict receipt echoes it. Missing or foreign origins share not-found behavior; conflicts map to an operation conflict. Requests and receipts are bounded, and responses use `Cache-Control: no-store`.
+
+## Broker profile
+
+`rustfs/src/admin/handlers/plugin_attempt.rs` implements `POST /rustfs/admin/v3/plugin-delegations/{id}/issue-attempt`. The signer must be an ordinary IAM user with `admin:IssuePluginAttempt`, independently listed in `RUSTFS_PLUGIN_BROKERS`:
+
+```json
+{"broker-access-key":"deployment-name"}
+```
+
+This configuration contains public access keys, not secrets. It is immutable per process. Missing or invalid configuration disables broker issuance. The broker is a trusted Controller identity; ordinary users cannot substitute their own request fields for Controller validation.
+
+The request carries `tenant`, `run_id`, `attempt_id`, `revision`, `deployment`, `input_bucket`, `input_key`, `input_version`, `output_bucket`, `output_prefix` and `ttl_seconds`. IDs must be non-nil. Both profiles accept one exact input version and an output prefix equal to:
+
+```text
+<delegation-output-prefix><lowercase-hex-tenant>/<run-uuid>/<attempt-uuid>/
+```
+
+The session policy permits only `s3:GetObjectVersion` for that input with an exact `s3:VersionId`, and `s3:PutObject` beneath that attempt prefix. Credential lifetime is at most 900 seconds and cannot exceed delegation expiry. The Controller must additionally cap it to its validated lease and hard deadline.
+
+The original user's current IAM remains the parent permission boundary on every S3 request. The server's signing key only seals the token; it is not the plugin's authorization identity. Broker identity and original user identity are separate.
+
+External policy plugins must be disabled: their authorization path does not enforce this built-in session-policy boundary. Initializing, failed and ready plugin states all reject issuance. Attempt tokens carry a signed, persisted marker: after restart or on another node, marked credentials are accepted only by built-in STS authorization. A denied marked request returns a terminal error, so public bucket policies cannot bypass its session scope. The first profile also rejects parent policies containing conditions, because a broker request cannot reconstruct the original user's IP, MFA or other request context. It does not silently replace that context with the broker's.
+
+## Response and failures
+
+Successful issuance returns `version`, `delegation_id`, `delegation_revision`, `owner_access_key`, `access_key_id`, `secret_access_key`, `session_token` and `expires_at_unix_seconds`, with `Cache-Control: no-store`. The Controller verifies the returned delegation and owner against the accepted caller before delivery. Credentials must never enter logs, metrics or task result manifests.
+
+Missing records and records owned by a different user have the same read response. Revoked or expired records reject access. Storage failures remain errors. Post-persistence failures carry static `error_code`, `issued` and `issuance_unknown` facts without credentials; callers must reconcile an unknown outcome rather than automatically mint another credential.
+
+The route/action inventory is maintained in `rustfs/src/admin/route_policy.rs`. This contract does not imply event capture, physical container cleanup, restart reconciliation or upstream release acceptance.
+
+
+## Cross-bucket restriction profile v2
+
+The existing registration endpoint accepts this explicit v2 restriction:
+
+```json
+{
+  "version": 2,
+  "deployment": "runner-production",
+  "bucket": "source-images",
+  "input_prefix": "inputs/",
+  "output_bucket": "plugin-artifacts",
+  "output_prefix": "outputs/",
+  "expires_at_unix_seconds": 1893456000
+}
+```
+
+The example expiry must be replaced by a future value within the existing
+24-hour limit. `bucket` still identifies the input bucket. The existing
+`issue-attempt` request and credential response do not change: its
+`input_bucket` must equal `bucket`, and `output_bucket` must equal the explicit
+v2 output bucket. Neither a different bucket nor a sibling attempt prefix can
+be supplied by the broker. The exact input version and deterministic output
+prefix checks remain in force.
+
+A v1 restriction has neither `version` nor `output_bucket`; its JSON fields
+and same-bucket behavior are unchanged. V2 requires both `version: 2` and a
+nonempty, bounded, literal `output_bucket`. Missing pairs, explicit nulls,
+unknown versions and unknown fields are rejected rather than downgraded to v1.
+The immutable record envelope carries version 1 or 2 to match its restriction
+profile. Both remain in the existing IAM record namespace; no data migration
+or mutable record update is introduced. Readers reject mismatched envelope
+and restriction versions. Older readers reject v2, so deploy compatible
+readers before creating v2 records.
+
+V2 does not grant the original user additional permissions. Issuance retains
+its current-parent checks and post-persistence recheck/invalidation, and each
+S3 request still requires both the original user's current IAM policy and the
+attempt session policy to allow it. An explicit parent Deny or removal of
+output permission prevents writes even with an already issued token. No
+administrator credential substitutes for missing parent permission.
+
+Focused tests are `delegation_v1_json_remains_compatible`,
+`delegation_v2_requires_explicit_output_bucket`,
+`attempt_v2_policy_keeps_input_version_and_output_bucket` and
+`delegation_v2_persists_and_vends_with_real_parent_intersection`.
+The last uses the actual issuance handler, persistent IAM and four-disk
+storage, including a real input version and a third bucket allowed by the
+parent but forbidden by the delegation. Removing only the output-bucket
+comparison must fail `A03_CROSS_BUCKET_OUTPUT_BOUND`; parent intersection is
+checked independently with issued temporary credentials. These are internal
+handler/IAM tests, not signed HTTP or complete cross-bucket S3 execution.
+
+This profile adds no bucket-creation API, Runner binding support, credential
+endpoint or GC permission. Coordinating Runner's pinned binding with its
+result storage bucket remains a separate integration requirement.

docs/architecture/scanner-usage-publication.md

@@ -182,6 +182,18 @@ requires a compatibility window and a dedicated cleanup entry.
 | `.scanner-cycle.lock` | scanner runtime lock | Serializes cycle-level work. A missing lock object is not itself usage evidence. |
 | `.scanner-pause-backlog.json` | scanner pause and catch-up ledger | Tracks dirty usage, discovered lifecycle work, and full-scan catch-up while authoritative publication is fenced by data movement. It never grants publication admission. |
 
+The authoritative snapshot may include an optional `bucket_incarnation` in each
+bucket usage entry. The coordinator writes it only when every contributing set
+reports the same non-nil bucket UUID. Missing or conflicting identities leave
+that entry uncertified; they do not reject the usage publication or change quota
+admission. Veeam SOSAPI capacity reads require this proof to match the bucket
+incarnation read from authoritative storage. An old snapshot, a mixed-version
+writer that omits the field, a pending target bucket, or an unavailable identity
+therefore yields a retryable capacity error until a compatible scanner publishes
+a certified entry. The optional field is omitted when unavailable so older
+snapshot readers continue to see the original shape. This proof identifies the
+bucket generation; it does not make scanner usage a real-time quota ledger.
+
 ## Observed Snapshots
 
 Observed snapshots are a diagnostic and availability layer. They may be served

docs/operations/scanner-runtime-controls.md

@@ -529,17 +529,21 @@ The OTLP exporter records these node-local histograms for completed manager admi
 
 The two new histograms aggregate all observed admission sources and results without per-request labels. An ordinary uninterrupted admission partitions the phase into wait and hold. Admin forceStart releases these guards while cancelling overlaps, then reacquires them: the cancellation gap is included only in the original total phase, and the second acquisition contributes to wait. Cancellation subroutine work is outside these outer admission guard intervals. Recording happens after all three guards are released. They measure manager admission ownership, not namespace/object-lock waiting during repair. The status field `maxLockPhaseMicros` remains a manager-lifetime maximum, not a p95 sample. Keep same-window histogram counts and bucket resolution when deriving percentiles; missing observations do not mean zero latency. These metrics do not establish performance acceptance by themselves.
 
-## Experimental heal node admission
+## Experimental shared node admission
 
-`RUSTFS_HEAL_ADAPTIVE_ADMISSION=true` enables Linux cgroup-v2 feedback for the four object-heal entry points owned by the heal manager. It is off by default while full SSD performance acceptance is pending. Unsupported platforms reject an enabled setting. This does not yet control scanner walks, bucket/format repair or physical devices, and it is not a replacement for existing worker, disk or byte budgets.
+`RUSTFS_HEAL_ADAPTIVE_ADMISSION=true` enables Linux cgroup-v2 feedback shared by the heal manager’s four object-heal entry points and local Scanner namespace reads and object accounting. It is off by default while full SSD performance acceptance is pending. Unsupported platforms reject an enabled setting. This does not yet control the abandoned-child streaming list coordinator, bucket/format repair or physical devices, and it is not a replacement for existing worker, disk or byte budgets.
 
 The node samples its effective CPU quota/cpuset, ancestor memory headroom, CPU usage/throttling and CPU/memory/I/O pressure once per second. Sampling uses one blocking worker at a time. Resource reads retain their real start/end times: reads spanning over 20 ms or older than one second after all inputs return cannot renew admission. Counter rates use both read brackets conservatively. The concurrency cap is at most the rounded-up effective CPU count and 256 scheduling units; existing operator limits still apply independently. At most 1% memory headroom blocks new work. This is a pressure safeguard, not a memory reservation or a claim that concurrent repair buffers fit in the remaining bytes.
 
 Each complete sample leases admission for three seconds. Missing resource caps block new work; missing or low-confidence feedback retains at most one maintenance unit. CPU use above 90%, throttling or pressure above 1% of elapsed time, memory headroom at most 10%, foreground errors/cancellations, a foreground queue or a comparable foreground p99 regression reduce concurrency immediately. Recovery requires CPU use at most 70%, throttling/stalls at most 0.1% of elapsed time, at least 20% memory headroom, fresh foreground evidence and actual successful work. The existing controller probes one additional unit only after eight consecutive healthy seconds and cooldown. Limits affect new admission and do not revoke active work.
 
+The Scanner captures the same node owner once per bucket walk. Directory open/refill, entry type and size lookup, and object accounting try admission before their first storage poll; each unit ends when its operation future finishes. On contention, local and remote coordinators suspend the same traversal, release the bucket cache lease, and join the shared FIFO queue. They reacquire the cache lease and verify both cache revisions before resuming. A changed cache rejects the suspended result. Cancellation also drops the queued request; the existing cycle budget still bounds the walk. This retains directory and recursion state while allowing Heal to advance at capacity one, without repeatedly replaying a partially classified directory.
+
+Calls without a coordinating cache lease retain immediate resource deferral and useful partial-cache handling. Existing remote single-session ownership and local-disk admission shares remain in force. Disabled admission creates no request channel. Enabled walks use one bounded channel, with a response allocation and cache revision reads only on contention; the uncontended per-entry path adds no global lookup or task. The streaming abandoned-child coordinator requires a separate ownership boundary: retaining a node unit while it waits for a bounded-channel consumer that needs the same unit would deadlock at capacity one.
+
 Foreground comparison uses the existing complete response-body windows and shared admission snapshots. Each active class needs at least 100 completions and a finite p99 interval; this permits the percentile rank but is not a statistical confidence guarantee. Comparisons require the same active classes and rates within 80–125% of a retained reference. A changed workload resets recovery. The reference is an observed workload window, not an independent background-off baseline. A p99 interval can justify stability only when its upper bound is within 5% of the reference lower bound; a lower bound above 105% of the reference upper bound is pressure. Overlapping/uncertain comparisons cannot justify growth. Missing queues, stale or repeated cuts, uncertain cut boundaries and low counts are not idle evidence.
 
-Admission waits at most 250 ms before returning the existing typed transient deferral, before polling storage or taking namespace locks. No-lock callers never wait. Queued read repair uses the same node gate; direct foreground ECStore calls remain outside this heal-manager adapter. Cancellation releases the non-cloneable node scheduling unit. Native work retains separate physical-I/O units, and unsuccessful/cancelled/dry-run work cannot increment the node's completed-work counter. This scheduling counter is not an authoritative heal receipt and cannot discharge repair responsibility.
+Heal admission waits at most 250 ms before returning the existing typed transient deferral, before polling storage or taking namespace locks. No-lock callers never wait. Queued read repair uses the same node gate; direct foreground ECStore calls remain outside this heal-manager adapter. Cancellation releases the non-cloneable node scheduling unit. Native work retains separate physical-I/O units, and unsuccessful/cancelled/dry-run work cannot increment the node's completed-work counter. This scheduling counter is not an authoritative heal receipt and cannot discharge repair responsibility.
 
 The `rustfs_background_node_admission_limit` and `rustfs_background_node_admission_active` gauges describe the last published sample, not a live reservation proof. A blocked sampler can leave these exports stale even though the admission lease has expired. Full disk-owner feedback, shared scanner scheduling, escaping-buffer byte ownership and the matched-release SSD matrix/hot-shrink/72-hour soak remain required before enabling this by default or claiming optimal performance.
 

fuzz/Cargo.toml

@@ -19,6 +19,18 @@ rustfs-security-governance = { path = "../crates/security-governance" }
 rustfs-utils = { path = "../crates/utils", features = ["compress", "path"] }
 serde_json = "1"
 
+[patch.crates-io]
+# Standalone workspaces must repeat the root workspace's fixed SigV4a backend.
+aws-sigv4 = { git = "https://github.com/smithy-lang/smithy-rs", rev = "5c1c4bca2ea7af97496e077c9f1a718eaac64bf8" }
+
+[patch."https://github.com/smithy-lang/smithy-rs"]
+# Keep the signer's path dependencies on the SDK's existing registry types.
+aws-credential-types = { version = "=1.3.1" }
+aws-smithy-eventstream = { version = "=0.61.6" }
+aws-smithy-http = { version = "=0.64.3" }
+aws-smithy-runtime-api = { version = "=1.19.2" }
+aws-smithy-types = { version = "=1.9.1" }
+
 [[bin]]
 name = "bucket_validation"
 path = "fuzz_targets/bucket_validation.rs"

rustfs/Cargo.toml

@@ -297,7 +297,7 @@ tokio-rustls = { workspace = true, default-features = false, features = ["loggin
 aws-smithy-runtime-api = { workspace = true, features = ["http-1x"] }
 aws-smithy-types = { workspace = true }
 google-cloud-auth = { workspace = true, optional = true }
-moka = { workspace = true, features = ["sync"] }
+moka = { workspace = true, features = ["future", "sync"] }
 xxhash-rust = { workspace = true, features = ["xxh3"] }
 aws-sdk-s3 = { workspace = true, default-features = false, features = ["sigv4a", "default-https-client", "rt-tokio"] }
 tokio-stream.workspace = true

rustfs/src/admin/handlers/mod.rs

@@ -52,6 +52,8 @@ pub mod object_data_cache;
 pub mod object_zip_download;
 pub mod oidc;
 pub mod on_demand_migration;
+pub mod plugin_attempt;
+pub mod plugin_delegation;
 pub mod plugins_catalog;
 pub mod plugins_instances;
 pub mod policies;

rustfs/src/admin/handlers/plugin_attempt.rs

@@ -0,0 +1,568 @@
+// Copyright 2026 RustFS Team
+// SPDX-License-Identifier: Apache-2.0
+//! Restricted vending for explicitly configured brokers, never AssumeRole chaining.
+use super::plugin_delegation::{owner, response, storage_error};
+use crate::{
+    admin::{
+        router::{AdminOperation, Operation, S3Router},
+        runtime_sources,
+        storage_api::s3::{self, Body, S3Error, S3ErrorCode, S3Request, S3Response, S3Result},
+    },
+    auth::check_key_valid_with_context,
+    server::ADMIN_PREFIX,
+};
+use http::{Method, StatusCode};
+use matchit::Params;
+use rustfs_iam::{
+    delegation::Delegation,
+    sys::{PLUGIN_ATTEMPT_CREDENTIAL_CLAIM, SESSION_POLICY_NAME},
+};
+use rustfs_policy::{
+    auth::get_new_credentials_with_metadata,
+    policy::{
+        Args, Policy,
+        action::{Action, AdminAction, S3Action},
+    },
+};
+use serde::{Deserialize, Serialize};
+use std::{
+    collections::HashMap,
+    sync::OnceLock,
+    time::{Duration, SystemTime, UNIX_EPOCH},
+};
+use time::OffsetDateTime;
+
+// Operator configuration contains public signer access keys, not credentials.
+// Empty/invalid configuration disables the endpoint. It is immutable per process.
+static BROKERS: OnceLock<Option<HashMap<String, String>>> = OnceLock::new();
+fn configured_deployment(key: &str) -> Option<&'static str> {
+    BROKERS
+        .get_or_init(|| {
+            let raw = std::env::var("RUSTFS_PLUGIN_BROKERS").ok()?;
+            let map: HashMap<String, String> = serde_json::from_str(&raw).ok()?;
+            if map.is_empty()
+                || map
+                    .iter()
+                    .any(|(k, v)| k.is_empty() || v.is_empty() || k.len() > 1024 || v.len() > 1024)
+            {
+                return None;
+            }
+            Some(map)
+        })
+        .as_ref()?
+        .get(key)
+        .map(String::as_str)
+}
+
+#[derive(Deserialize)]
+#[serde(deny_unknown_fields)]
+struct Attempt {
+    tenant: String,
+    run_id: uuid::Uuid,
+    attempt_id: uuid::Uuid,
+    revision: String,
+    deployment: String,
+    input_bucket: String,
+    input_key: String,
+    input_version: String,
+    output_bucket: String,
+    output_prefix: String,
+    ttl_seconds: u64,
+}
+#[derive(Serialize)]
+struct Issued {
+    version: u32,
+    delegation_id: String,
+    delegation_revision: String,
+    owner_access_key: String,
+    access_key_id: String,
+    secret_access_key: String,
+    session_token: String,
+    expires_at_unix_seconds: i64,
+}
+
+pub fn register_plugin_attempt_route(router: &mut S3Router<AdminOperation>) -> std::io::Result<()> {
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/issue-attempt"),
+        AdminOperation(&Issue),
+    )?;
+    Ok(())
+}
+fn now() -> S3Result<u64> {
+    SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .map(|d| d.as_secs())
+        .map_err(|_| s3::error(S3ErrorCode::InternalError, "clock unavailable"))
+}
+fn literal(value: &str) -> bool {
+    !value.is_empty()
+        && value.len() <= 1024
+        && !value.contains("${")
+        && !value.chars().any(|c| c.is_control() || matches!(c, '*' | '?'))
+}
+fn session_policy(record: &Delegation, attempt: &Attempt) -> S3Result<Policy> {
+    let restriction = &record.restrictions;
+    // Stored records from earlier versions must obey the same literal rules.
+    restriction.validate(record.created_at_unix_seconds).map_err(storage_error)?;
+    let exact_output = format!(
+        "{}{}/{}/{}/",
+        restriction.output_prefix,
+        hex_simd::encode_to_string(attempt.tenant.as_bytes(), hex_simd::AsciiCase::Lower),
+        attempt.run_id,
+        attempt.attempt_id
+    );
+    if attempt.tenant.is_empty()
+        || attempt.tenant.len() > 1024
+        || attempt.run_id.is_nil()
+        || attempt.attempt_id.is_nil()
+        || attempt.output_prefix != exact_output
+        || attempt.revision != record.revision
+        || attempt.deployment != restriction.deployment
+        || attempt.input_bucket != restriction.bucket
+        || attempt.output_bucket != restriction.output_bucket().map_err(storage_error)?
+        || !literal(&attempt.input_key)
+        || !attempt.input_key.starts_with(&restriction.input_prefix)
+        || !literal(&attempt.input_version)
+        || attempt.input_version == "null"
+        || !literal(&attempt.output_prefix)
+        || !attempt.output_prefix.starts_with(&restriction.output_prefix)
+        || attempt.output_prefix == restriction.output_prefix
+        || !attempt.output_prefix.ends_with('/')
+        || !(1..=900).contains(&attempt.ttl_seconds)
+    {
+        return Err(s3::error(S3ErrorCode::AccessDenied, "attempt restriction rejected"));
+    }
+    let value = serde_json::json!({"Version":"2012-10-17","Statement":[
+        {"Effect":"Allow","Action":["s3:GetObjectVersion"],"Resource":[format!("arn:aws:s3:::{}/{}",attempt.input_bucket,attempt.input_key)],"Condition":{"StringEquals":{"s3:VersionId":attempt.input_version}}},
+        {"Effect":"Allow","Action":["s3:PutObject"],"Resource":[format!("arn:aws:s3:::{}/{}*",attempt.output_bucket,attempt.output_prefix)]}
+    ]});
+    // Condition operators borrow their keys while the policy is decoded.
+    let bytes = serde_json::to_vec(&value).map_err(|_| s3::error(S3ErrorCode::InternalError, "attempt policy unavailable"))?;
+    serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InternalError, "attempt policy unavailable"))
+}
+
+fn issuance_error(code: &'static str, issued: bool, unknown: bool) -> S3Result<S3Response<(StatusCode, Body)>> {
+    let mut answer = response(&serde_json::json!({"error_code":code,"issued":issued,"issuance_unknown":unknown}))?;
+    answer.output.0 = StatusCode::SERVICE_UNAVAILABLE;
+    Ok(answer)
+}
+fn same_parent_authority(before_names: &[String], before_policy: &Policy, after_names: &[String], after_policy: &Policy) -> bool {
+    fn names(names: &[String]) -> Vec<&str> {
+        let mut names: Vec<_> = names.iter().map(String::as_str).collect();
+        names.sort_unstable();
+        names.dedup();
+        names
+    }
+    fn statements(policy: &Policy) -> Option<Vec<Vec<u8>>> {
+        let mut statements = policy
+            .statements
+            .iter()
+            .map(serde_json::to_vec)
+            .collect::<Result<Vec<_>, _>>()
+            .ok()?;
+        statements.sort_unstable();
+        Some(statements)
+    }
+
+    names(before_names) == names(after_names)
+        && matches!(
+            (statements(before_policy), statements(after_policy)),
+            (Some(before), Some(after)) if before == after
+        )
+}
+async fn require_builtin_authorization() -> S3Result<()> {
+    rustfs_iam::sys::IamSys::<rustfs_iam::store::object::ObjectStore>::ensure_restricted_credential_vending()
+        .await
+        .map_err(|_| s3::error(S3ErrorCode::AccessDenied, "external policy plugin unsupported for attempt credentials"))
+}
+
+struct Issue;
+#[async_trait::async_trait]
+impl Operation for Issue {
+    async fn call(&self, mut req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        require_builtin_authorization().await?;
+        let (iam, broker) = owner(&req, AdminAction::IssuePluginAttemptAction).await?;
+        let deployment =
+            configured_deployment(&broker).ok_or_else(|| s3::error(S3ErrorCode::AccessDenied, "broker deployment rejected"))?;
+        let context = runtime_sources::app_context_from_req(&req)
+            .ok_or_else(|| s3::error(S3ErrorCode::InternalError, "application context unavailable"))?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "attempt body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "attempt body unavailable"))?;
+        let attempt: Attempt =
+            serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid attempt request"))?;
+        if attempt.deployment != deployment {
+            return Err(s3::error(S3ErrorCode::AccessDenied, "broker deployment rejected"));
+        }
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let record = iam
+            .read_active_plugin_delegation_for_broker(id, now()?)
+            .await
+            .map_err(storage_error)?;
+        let policy = session_policy(&record, &attempt)?;
+        let (principal, root) = check_key_valid_with_context("", &record.owner_access_key, Some(context.as_ref())).await?;
+        if root || principal.is_temp() || principal.is_service_account() {
+            return Err(s3::error(S3ErrorCode::AccessDenied, "original user required"));
+        }
+        // A broker request cannot reconstruct the original user's IP/MFA/tag
+        // conditions. This first profile rejects conditional parent policies.
+        let policies = iam
+            .policy_db_get(&principal.access_key, &principal.groups)
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InternalError, "parent policy unavailable"))?;
+        let parent_policy = iam.get_combined_policy(&policies).await;
+        if policies.is_empty() || parent_policy.statements.iter().any(|s| !s.conditions.is_empty()) {
+            return Err(s3::error(S3ErrorCode::AccessDenied, "parent condition context unsupported"));
+        }
+        let mut conditions = HashMap::new();
+        conditions.insert("s3:VersionId".to_owned(), vec![attempt.input_version.clone()]);
+        if !iam
+            .is_allowed(&Args {
+                account: &principal.access_key,
+                groups: &principal.groups,
+                action: Action::S3Action(S3Action::GetObjectVersionAction),
+                bucket: &attempt.input_bucket,
+                object: &attempt.input_key,
+                conditions: &conditions,
+                is_owner: false,
+                claims: principal.claims_or_empty(),
+                deny_only: false,
+            })
+            .await
+        {
+            return Err(s3::error(S3ErrorCode::AccessDenied, "parent input rejected"));
+        }
+        let expiration = now()?
+            .checked_add(attempt.ttl_seconds)
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "invalid expiration"))?
+            .min(record.restrictions.expires_at_unix_seconds);
+        let expires_at = OffsetDateTime::from_unix_timestamp(
+            i64::try_from(expiration).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid expiration"))?,
+        )
+        .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid expiration"))?;
+        let mut claims = principal.claims.clone().unwrap_or_default();
+        claims.insert(PLUGIN_ATTEMPT_CREDENTIAL_CLAIM.into(), serde_json::Value::Bool(true));
+        claims.insert("exp".into(), serde_json::json!(expires_at.unix_timestamp()));
+        claims.insert("parent".into(), serde_json::json!(principal.access_key));
+        let bytes =
+            serde_json::to_vec(&policy).map_err(|_| s3::error(S3ErrorCode::InternalError, "attempt policy unavailable"))?;
+        claims.insert(
+            SESSION_POLICY_NAME.into(),
+            serde_json::json!(base64_simd::URL_SAFE_NO_PAD.encode_to_string(&bytes)),
+        );
+        let fresh = iam
+            .read_active_plugin_delegation_for_broker(id, now()?)
+            .await
+            .map_err(storage_error)?;
+        if fresh != record {
+            return Err(s3::error(S3ErrorCode::AccessDenied, "attempt authority changed"));
+        }
+        owner(&req, AdminAction::IssuePluginAttemptAction).await?;
+        require_builtin_authorization().await?;
+        let signing = context
+            .action_credentials()
+            .get()
+            .ok_or_else(|| s3::error(S3ErrorCode::InternalError, "token signer unavailable"))?;
+        // The server key seals the token only. Authorization above uses the
+        // original user's current IAM, and S3 continues its parent intersection.
+        let mut credential = get_new_credentials_with_metadata(&claims, &signing.secret_key)
+            .map_err(|_| s3::error(S3ErrorCode::InternalError, "attempt credential unavailable"))?;
+        credential.parent_user = principal.access_key.clone();
+        if iam.set_temp_user(&credential.access_key, &credential, None).await.is_err() {
+            return issuance_error("PLUGIN_ATTEMPT_ISSUANCE_UNKNOWN", false, true);
+        }
+        // No atomic IAM/delegation transaction spans persistence. Recheck and
+        // invalidate the generated credential if any authority changed.
+        let valid = async {
+            require_builtin_authorization().await?;
+            let after = iam
+                .read_active_plugin_delegation_for_broker(id, now()?)
+                .await
+                .map_err(storage_error)?;
+            let (current, current_root) =
+                check_key_valid_with_context("", &record.owner_access_key, Some(context.as_ref())).await?;
+            let names = iam
+                .policy_db_get(&current.access_key, &current.groups)
+                .await
+                .map_err(|_| s3::error(S3ErrorCode::InternalError, "parent policy unavailable"))?;
+            let current_policy = iam.get_combined_policy(&names).await;
+            if after != record
+                || current_root
+                || current.is_temp()
+                || current.is_service_account()
+                || current.secret_key != principal.secret_key
+                || !same_parent_authority(&policies, &parent_policy, &names, &current_policy)
+            {
+                return Err(s3::error(S3ErrorCode::AccessDenied, "attempt authority changed"));
+            }
+            // Re-evaluate the broker against its real signed request context.
+            owner(&req, AdminAction::IssuePluginAttemptAction).await?;
+            Ok::<(), S3Error>(())
+        }
+        .await;
+        if valid.is_err() {
+            if iam.delete_temp_account(&credential.access_key, true).await.is_err() {
+                return issuance_error("PLUGIN_ATTEMPT_INVALIDATION_UNKNOWN", true, true);
+            }
+            return issuance_error("PLUGIN_ATTEMPT_POST_ISSUANCE_REJECTED", true, false);
+        }
+        response(&Issued {
+            version: 1,
+            delegation_id: record.id,
+            delegation_revision: record.revision,
+            owner_access_key: record.owner_access_key,
+            access_key_id: credential.access_key,
+            secret_access_key: credential.secret_key,
+            session_token: credential.session_token,
+            expires_at_unix_seconds: expires_at.unix_timestamp(),
+        })
+    }
+}
+
+#[cfg(test)]
+#[path = "plugin_attempt_v2_tests.rs"]
+mod v2_tests;
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[test]
+    fn parent_authority_recheck_ignores_policy_order_but_detects_changes() {
+        let first: Policy = serde_json::from_value(serde_json::json!({
+            "Version":"2012-10-17",
+            "Statement":[
+                {"Effect":"Allow","Action":"s3:GetObject","Resource":"arn:aws:s3:::photos/input/*"},
+                {"Effect":"Allow","Action":"s3:PutObject","Resource":"arn:aws:s3:::photos/output/*"}
+            ]
+        }))
+        .unwrap();
+        let reordered: Policy = serde_json::from_value(serde_json::json!({
+            "Version":"2012-10-17",
+            "Statement":[
+                {"Effect":"Allow","Action":"s3:PutObject","Resource":"arn:aws:s3:::photos/output/*"},
+                {"Effect":"Allow","Action":"s3:GetObject","Resource":"arn:aws:s3:::photos/input/*"}
+            ]
+        }))
+        .unwrap();
+        let before_names = vec!["owner-policy".to_owned(), "bucket-policy".to_owned()];
+        let after_names = vec!["bucket-policy".to_owned(), "owner-policy".to_owned()];
+        assert!(same_parent_authority(&before_names, &first, &after_names, &reordered));
+
+        let changed: Policy = serde_json::from_value(serde_json::json!({
+            "Version":"2012-10-17",
+            "Statement":[
+                {"Effect":"Allow","Action":"s3:GetObject","Resource":"arn:aws:s3:::photos/input/*"},
+                {"Effect":"Allow","Action":"s3:DeleteObject","Resource":"arn:aws:s3:::photos/output/*"}
+            ]
+        }))
+        .unwrap();
+        assert!(!same_parent_authority(&before_names, &first, &after_names, &changed));
+        let changed_resource: Policy = serde_json::from_value(serde_json::json!({
+            "Version":"2012-10-17",
+            "Statement":[
+                {"Effect":"Allow","Action":"s3:GetObject","Resource":"arn:aws:s3:::photos/input/*"},
+                {"Effect":"Allow","Action":"s3:PutObject","Resource":"arn:aws:s3:::photos/private/*"}
+            ]
+        }))
+        .unwrap();
+        assert!(!same_parent_authority(&before_names, &first, &after_names, &changed_resource));
+        let added_deny: Policy = serde_json::from_value(serde_json::json!({
+            "Version":"2012-10-17",
+            "Statement":[
+                {"Effect":"Deny","Action":"s3:GetObject","Resource":"arn:aws:s3:::photos/input/private/*"},
+                {"Effect":"Allow","Action":"s3:GetObject","Resource":"arn:aws:s3:::photos/input/*"},
+                {"Effect":"Allow","Action":"s3:PutObject","Resource":"arn:aws:s3:::photos/output/*"}
+            ]
+        }))
+        .unwrap();
+        assert!(!same_parent_authority(&before_names, &first, &after_names, &added_deny));
+        assert!(!same_parent_authority(&before_names, &first, &["other-policy".to_owned()], &first));
+    }
+    #[tokio::test]
+    async fn attempt_policy_keeps_exact_version_and_narrow_output() {
+        let record = Delegation {
+            version: 1,
+            id: "a".repeat(32),
+            revision: "a".repeat(32),
+            owner_access_key: "user".into(),
+            created_at_unix_seconds: 1,
+            restrictions: rustfs_iam::delegation::Restrictions {
+                version: None,
+                output_bucket: None,
+                deployment: "runner".into(),
+                bucket: "photos".into(),
+                input_prefix: "input/".into(),
+                output_prefix: "output/".into(),
+                expires_at_unix_seconds: 1000,
+            },
+        };
+        let run_id = uuid::Uuid::new_v4();
+        let attempt_id = uuid::Uuid::new_v4();
+        let output_prefix = format!(
+            "output/{}/{}/{}/",
+            hex_simd::encode_to_string(b"tenant", hex_simd::AsciiCase::Lower),
+            run_id,
+            attempt_id
+        );
+        let mut attempt = Attempt {
+            tenant: "tenant".into(),
+            run_id,
+            attempt_id,
+            revision: record.revision.clone(),
+            deployment: "runner".into(),
+            input_bucket: "photos".into(),
+            input_key: "input/photo.png".into(),
+            input_version: "version-1".into(),
+            output_bucket: "photos".into(),
+            output_prefix: output_prefix.clone(),
+            ttl_seconds: 60,
+        };
+        let policy = session_policy(&record, &attempt).unwrap();
+        let scoped_output = format!("{output_prefix}result");
+        let groups = None;
+        let claims = HashMap::new();
+        for (action, object, version, expected) in [
+            (S3Action::GetObjectVersionAction, "input/photo.png", Some("version-1"), true),
+            (S3Action::GetObjectVersionAction, "input/photo.png", Some("version-2"), false),
+            (S3Action::GetObjectVersionAction, "input/photo.png", None, false),
+            (S3Action::GetObjectAction, "input/photo.png", None, false),
+            (S3Action::PutObjectAction, scoped_output.as_str(), None, true),
+            (S3Action::PutObjectAction, "outside/result", None, false),
+            (S3Action::PutObjectAction, "output/result", None, false),
+        ] {
+            let conditions = version
+                .map(|value| HashMap::from([("versionid".into(), vec![value.into()])]))
+                .unwrap_or_default();
+            assert_eq!(
+                policy
+                    .is_allowed(&Args {
+                        account: "user",
+                        groups: &groups,
+                        action: Action::S3Action(action),
+                        bucket: "photos",
+                        object,
+                        conditions: &conditions,
+                        is_owner: false,
+                        claims: &claims,
+                        deny_only: false,
+                    })
+                    .await,
+                expected,
+                "attempt policy action={action:?} object={object} version={version:?}"
+            );
+        }
+        attempt.output_bucket = "artifacts".into();
+        assert!(
+            session_policy(&record, &attempt).is_err(),
+            "v1 still requires the input bucket for output"
+        );
+        attempt.output_bucket = "photos".into();
+        attempt.output_prefix = "output/".into();
+        assert!(session_policy(&record, &attempt).is_err());
+        attempt.output_prefix = output_prefix;
+        attempt.input_key = "outside/photo.png".into();
+        assert!(session_policy(&record, &attempt).is_err());
+    }
+    #[tokio::test]
+    async fn attempt_v2_policy_keeps_input_version_and_output_bucket() {
+        let record: Delegation = serde_json::from_value(serde_json::json!({
+            "version":2,"id":"a".repeat(32),"revision":"a".repeat(32),"owner_access_key":"user",
+            "created_at_unix_seconds":1,"restrictions":{"version":2,"deployment":"runner","bucket":"photos",
+            "input_prefix":"input/","output_bucket":"artifacts","output_prefix":"output/","expires_at_unix_seconds":1000}
+        }))
+        .expect("explicit v2 delegation");
+        let run_id = uuid::Uuid::new_v4();
+        let attempt_id = uuid::Uuid::new_v4();
+        let output = format!("output/74656e616e74/{run_id}/{attempt_id}/");
+        let mut attempt = Attempt {
+            tenant: "tenant".into(),
+            run_id,
+            attempt_id,
+            revision: record.revision.clone(),
+            deployment: "runner".into(),
+            input_bucket: "photos".into(),
+            input_key: "input/photo.png".into(),
+            input_version: "version-1".into(),
+            output_bucket: "artifacts".into(),
+            output_prefix: output.clone(),
+            ttl_seconds: 60,
+        };
+        let policy = session_policy(&record, &attempt).expect("v2 scope");
+        let result = format!("{output}result");
+        for (action, bucket, object, version, expected) in [
+            (S3Action::GetObjectVersionAction, "photos", "input/photo.png", Some("version-1"), true),
+            (S3Action::GetObjectVersionAction, "photos", "input/photo.png", Some("version-2"), false),
+            (S3Action::GetObjectVersionAction, "artifacts", "input/photo.png", Some("version-1"), false),
+            (S3Action::PutObjectAction, "artifacts", result.as_str(), None, true),
+            (S3Action::PutObjectAction, "photos", result.as_str(), None, false),
+            (S3Action::PutObjectAction, "third", result.as_str(), None, false),
+            (S3Action::PutObjectAction, "artifacts", "output/other/result", None, false),
+        ] {
+            let conditions = version
+                .map(|v| HashMap::from([("versionid".into(), vec![v.into()])]))
+                .unwrap_or_default();
+            assert_eq!(
+                policy
+                    .is_allowed(&Args {
+                        account: "user",
+                        groups: &None,
+                        action: Action::S3Action(action),
+                        bucket,
+                        object,
+                        conditions: &conditions,
+                        claims: &HashMap::new(),
+                        is_owner: false,
+                        deny_only: false
+                    })
+                    .await,
+                expected,
+                "A03_CROSS_BUCKET_SCOPE: bucket={bucket} object={object}"
+            );
+        }
+        attempt.output_bucket = "third".into();
+        assert!(session_policy(&record, &attempt).is_err(), "A03_CROSS_BUCKET_OUTPUT_BOUND");
+        attempt.output_bucket = "photos".into();
+        assert!(session_policy(&record, &attempt).is_err(), "A03_CROSS_BUCKET_OUTPUT_BOUND");
+        attempt.output_bucket = "artifacts".into();
+        attempt.input_bucket = "artifacts".into();
+        assert!(session_policy(&record, &attempt).is_err(), "A03_CROSS_BUCKET_INPUT_BOUND");
+    }
+
+    #[tokio::test]
+    async fn actual_policy_variable_resolution_is_rejected_by_literal_scope() {
+        let resource = rustfs_policy::policy::resource::Resource::S3("photos/input/${aws:username}.png".into());
+        let conditions = HashMap::from([("username".into(), vec!["alice".into()])]);
+        let resolver =
+            rustfs_policy::policy::variables::VariableResolver::new(rustfs_policy::policy::variables::VariableContext {
+                username: Some("alice".into()),
+                ..Default::default()
+            });
+        assert!(
+            resource
+                .is_match_with_resolver("photos/input/alice.png", &conditions, Some(&resolver))
+                .await,
+            "C07_LITERAL_SCOPE_BOUND: actual policy engine substitutes resource variables"
+        );
+        assert!(
+            !literal("input/${aws:username}.png"),
+            "C07_LITERAL_SCOPE_BOUND: requested resources must stay literal"
+        );
+        let restriction = rustfs_iam::delegation::Restrictions {
+            version: None,
+            output_bucket: None,
+            deployment: "runner".into(),
+            bucket: "photos".into(),
+            input_prefix: "input/${aws:username}/".into(),
+            output_prefix: "output/".into(),
+            expires_at_unix_seconds: 200,
+        };
+        assert!(
+            restriction.validate(100).is_err(),
+            "C07_LITERAL_SCOPE_BOUND: legacy stored variable restrictions are rejected"
+        );
+    }
+}

rustfs/src/admin/handlers/plugin_attempt_v2_tests.rs

@@ -0,0 +1,365 @@
+// Copyright 2026 RustFS Team
+// SPDX-License-Identifier: Apache-2.0
+//! Real handler, persisted IAM and four-disk storage; this is not a signed HTTP/S3 end-to-end test.
+use super::*;
+use crate::admin::{
+    runtime_sources::{AppContext, IamInterface, KmsInterface, ServerContextSlot},
+    storage_api::{
+        ECStore,
+        contract::bucket::{BucketOperations as _, MakeBucketOptions},
+        contract::object::ObjectIO as _,
+    },
+};
+use crate::storage::storage_api::{StorageObjectOptions, StoragePutObjReader};
+use http_body_util::BodyExt as _;
+use rustfs_iam::{
+    store::{
+        Store as _, UserType,
+        object::{IAM_CONFIG_PREFIX, ObjectStore},
+    },
+    sys::IamSys,
+};
+use rustfs_madmin::{AccountStatus, AddOrUpdateUserReq};
+use serde_json::{Value, json};
+use std::sync::Arc;
+
+const PARENT: &str = "cross-parent";
+const BROKER: &str = "cross-broker";
+const SECRET: &str = "cross-bucket-test-secret";
+const ROOT: &str = "cross-root";
+const ROOT_SECRET: &str = "cross-bucket-root-test-secret";
+
+struct RequestIam(Arc<IamSys<ObjectStore>>);
+impl IamInterface for RequestIam {
+    fn handle(&self) -> Arc<IamSys<ObjectStore>> {
+        self.0.clone()
+    }
+    fn is_ready(&self) -> bool {
+        true
+    }
+}
+struct RequestKms;
+impl KmsInterface for RequestKms {
+    fn handle(&self) -> Arc<rustfs_kms::KmsServiceManager> {
+        Arc::new(rustfs_kms::KmsServiceManager::new())
+    }
+}
+struct Fixture {
+    _root: tempfile::TempDir,
+    store: Arc<ECStore>,
+    iam: Arc<IamSys<ObjectStore>>,
+    context: Arc<AppContext>,
+    input_version: String,
+}
+impl Fixture {
+    async fn new() -> Self {
+        let root = tempfile::tempdir().expect("cross-bucket storage root");
+        let env = rustfs_test_utils::TestECStoreEnv::builder()
+            .base_dir(root.path())
+            .disk_count(4)
+            .build()
+            .await;
+        assert_eq!(env.disk_paths.len(), 4);
+        let store = env.ecstore;
+        for bucket in ["photos", "artifacts", "third"] {
+            store
+                .make_bucket(
+                    bucket,
+                    &MakeBucketOptions {
+                        versioning_enabled: true,
+                        ..Default::default()
+                    },
+                )
+                .await
+                .expect("real versioned bucket");
+        }
+        let object = store
+            .put_object(
+                "photos",
+                "input/photo.png",
+                &mut StoragePutObjReader::from_vec(vec![0xA5; 273]),
+                &StorageObjectOptions {
+                    versioned: true,
+                    ..Default::default()
+                },
+            )
+            .await
+            .expect("real input version");
+        let input_version = object.version_id.expect("exact input version").to_string();
+        ObjectStore::new(store.clone())
+            .save_iam_config(json!({"version":1}), format!("{}/format.json", *IAM_CONFIG_PREFIX))
+            .await
+            .expect("persistent IAM format");
+        let iam = rustfs_iam::build_iam_sys(store.clone()).await.expect("real IAM");
+        let context = Arc::new(AppContext::new(store.clone(), Arc::new(RequestIam(iam.clone())), Arc::new(RequestKms)));
+        assert!(context.publish_action_credentials(rustfs_credentials::Credentials {
+            access_key: ROOT.into(),
+            secret_key: ROOT_SECRET.into(),
+            status: "on".into(),
+            ..Default::default()
+        }));
+        let fixture = Self {
+            _root: root,
+            store,
+            iam,
+            context,
+            input_version,
+        };
+        fixture.user(PARENT, Self::parent_policy(true, false)).await;
+        fixture
+            .user(
+                BROKER,
+                json!({"Version":"2012-10-17","Statement":[{
+            "Effect":"Allow","Action":"admin:IssuePluginAttempt"}]}),
+            )
+            .await;
+        fixture
+    }
+    fn parent_policy(output: bool, deny: bool) -> Value {
+        let mut resources = vec!["arn:aws:s3:::photos/output/*", "arn:aws:s3:::third/output/*"];
+        if output {
+            resources.push("arn:aws:s3:::artifacts/output/*");
+        }
+        let mut statements = vec![
+            json!({"Effect":"Allow","Action":"s3:GetObjectVersion","Resource":"arn:aws:s3:::photos/input/*"}),
+            json!({"Effect":"Allow","Action":"s3:PutObject","Resource":resources}),
+        ];
+        if deny {
+            statements.push(json!({"Effect":"Deny","Action":"s3:PutObject","Resource":"arn:aws:s3:::artifacts/*"}));
+        }
+        json!({"Version":"2012-10-17","Statement":statements})
+    }
+    async fn policy(&self, name: &str, value: Value) {
+        let policy = Policy::parse_config(&serde_json::to_vec(&value).expect("policy JSON")).expect("real IAM policy");
+        self.iam.set_policy(name, policy).await.expect("persist policy");
+    }
+    async fn user(&self, name: &str, policy: Value) {
+        self.iam
+            .create_user(
+                name,
+                &AddOrUpdateUserReq {
+                    secret_key: SECRET.into(),
+                    policy: None,
+                    status: AccountStatus::Enabled,
+                },
+            )
+            .await
+            .expect("create real user");
+        self.policy(name, policy).await;
+        self.iam
+            .policy_db_set(name, UserType::Reg, false, name)
+            .await
+            .expect("attach actual IAM policy");
+    }
+    fn request(&self, body: &Value) -> S3Request<Body> {
+        let slot = ServerContextSlot::new();
+        assert!(slot.install(self.context.clone()));
+        let mut req = S3Request {
+            input: Body::from(serde_json::to_vec(body).expect("attempt JSON")),
+            method: Method::POST,
+            uri: http::Uri::default(),
+            headers: http::HeaderMap::new(),
+            extensions: http::Extensions::new(),
+            credentials: None,
+            region: None,
+            service: None,
+            trailing_headers: None,
+        };
+        req.extensions.insert(slot);
+        req.method = Method::POST;
+        req.credentials = Some(s3::auth::Credentials {
+            access_key: BROKER.into(),
+            secret_key: s3::auth::SecretKey::from(SECRET.to_owned()),
+        });
+        req
+    }
+    async fn issue(&self, record: &Delegation, body: &Value) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let mut router = matchit::Router::new();
+        router.insert("/{id}", ()).expect("parameter route");
+        let path = format!("/{}", record.id);
+        Issue
+            .call(self.request(body), router.at(&path).expect("actual delegation ID").params)
+            .await
+    }
+    async fn allowed(
+        &self,
+        credential: &rustfs_credentials::Credentials,
+        action: S3Action,
+        bucket: &str,
+        object: &str,
+        version: Option<&str>,
+    ) -> bool {
+        let conditions = version
+            .map(|v| HashMap::from([("versionid".into(), vec![v.into()])]))
+            .unwrap_or_default();
+        self.iam
+            .is_allowed(&Args {
+                account: &credential.access_key,
+                groups: &credential.groups,
+                action: Action::S3Action(action),
+                bucket,
+                object,
+                conditions: &conditions,
+                claims: credential.claims_or_empty(),
+                is_owner: false,
+                deny_only: false,
+            })
+            .await
+    }
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+#[serial_test::serial]
+async fn delegation_v2_persists_and_vends_with_real_parent_intersection() {
+    temp_env::async_with_vars(
+        [
+            ("RUSTFS_PLUGIN_BROKERS", Some(r#"{"cross-broker":"runner"}"#)),
+            ("RUSTFS_SKIP_BACKGROUND_TASK", Some("1")),
+        ],
+        async {
+            let fixture = Fixture::new().await;
+            let now = now().expect("clock");
+            let legacy = json!({"deployment":"runner","bucket":"photos","input_prefix":"input/",
+            "output_prefix":"output/","expires_at_unix_seconds":now+3600});
+            let v1 = fixture
+                .iam
+                .create_plugin_delegation(PARENT, serde_json::from_value(legacy.clone()).expect("v1"), now)
+                .await
+                .expect("persist legacy delegation");
+            assert_eq!(v1.version, 1);
+            assert_eq!(serde_json::to_value(&v1.restrictions).expect("v1 wire"), legacy);
+            let mut v2 = legacy;
+            v2["version"] = json!(2);
+            v2["output_bucket"] = json!("artifacts");
+            let record = fixture
+                .iam
+                .create_plugin_delegation(PARENT, serde_json::from_value(v2.clone()).expect("v2"), now)
+                .await
+                .expect("persist v2 delegation");
+            assert_eq!(record.version, 2);
+            let loaded = fixture
+                .iam
+                .read_active_plugin_delegation(PARENT, &record.id, now)
+                .await
+                .expect("strict stored v2");
+            assert!(loaded == record, "same persisted v2 identity");
+            assert_eq!(serde_json::to_value(&loaded.restrictions).expect("v2 wire"), v2);
+            // The record envelope and restriction profile cannot disagree on a persisted read.
+            let path = format!("config/iam/plugin-delegations/v1/{}/record.json", record.id);
+            let mut corrupt = serde_json::to_value(&record).expect("record JSON");
+            corrupt["version"] = json!(1);
+            ObjectStore::new(fixture.store.clone())
+                .save_iam_config(corrupt, &path)
+                .await
+                .expect("inject incompatible stored version");
+            assert!(
+                fixture
+                    .iam
+                    .read_active_plugin_delegation(PARENT, &record.id, now)
+                    .await
+                    .is_err(),
+                "mixed v1/v2 stored profiles fail closed"
+            );
+            ObjectStore::new(fixture.store.clone())
+                .save_iam_config(&record, &path)
+                .await
+                .expect("restore exact stored record");
+            let run = uuid::Uuid::new_v4();
+            let attempt = uuid::Uuid::new_v4();
+            let prefix = format!("output/74656e616e74/{run}/{attempt}/");
+            let body = json!({"tenant":"tenant","run_id":run,"attempt_id":attempt,"revision":record.revision,
+            "deployment":"runner","input_bucket":"photos","input_key":"input/photo.png","input_version":fixture.input_version,
+            "output_bucket":"artifacts","output_prefix":prefix,"ttl_seconds":60});
+            let loaded_v1 = fixture
+                .iam
+                .read_active_plugin_delegation(PARENT, &v1.id, now)
+                .await
+                .expect("read legacy record");
+            assert!(loaded_v1 == v1, "legacy persistent identity");
+            let mut legacy_body = body.clone();
+            legacy_body["revision"] = json!(v1.revision);
+            legacy_body["output_bucket"] = json!("photos");
+            let legacy_response = fixture.issue(&v1, &legacy_body).await.expect("legacy same-bucket issuance");
+            assert_eq!(legacy_response.output.0, StatusCode::OK);
+            let mut wrong = body.clone();
+            wrong["output_bucket"] = json!("third");
+            match fixture.issue(&record, &wrong).await {
+                Err(error) => assert_eq!(error.code(), &S3ErrorCode::AccessDenied),
+                Ok(_) => panic!("A03_CROSS_BUCKET_OUTPUT_BOUND"),
+            }
+            let response = fixture.issue(&record, &body).await.expect("actual v2 issuance");
+            assert_eq!(response.output.0, StatusCode::OK);
+            assert_eq!(response.headers[http::header::CACHE_CONTROL], "no-store");
+            let issued: Value =
+                serde_json::from_slice(&response.output.1.collect().await.expect("issued body").to_bytes()).expect("issued JSON");
+            let (credential, root) = check_key_valid_with_context(
+                issued["session_token"].as_str().expect("token"),
+                issued["access_key_id"].as_str().expect("access key"),
+                Some(fixture.context.as_ref()),
+            )
+            .await
+            .expect("persisted actual temporary identity");
+            assert!(!root && credential.is_temp());
+            let output = format!("{prefix}image.png");
+            for (action, bucket, object, version, expected) in [
+                (
+                    S3Action::GetObjectVersionAction,
+                    "photos",
+                    "input/photo.png",
+                    Some(fixture.input_version.as_str()),
+                    true,
+                ),
+                (
+                    S3Action::GetObjectVersionAction,
+                    "photos",
+                    "input/photo.png",
+                    Some("wrong-version"),
+                    false,
+                ),
+                (S3Action::GetObjectAction, "photos", "input/photo.png", None, false),
+                (S3Action::PutObjectAction, "artifacts", output.as_str(), None, true),
+                (S3Action::PutObjectAction, "photos", output.as_str(), None, false),
+                (S3Action::PutObjectAction, "third", output.as_str(), None, false),
+                (S3Action::PutObjectAction, "artifacts", "output/other/image.png", None, false),
+            ] {
+                assert_eq!(
+                    fixture.allowed(&credential, action, bucket, object, version).await,
+                    expected,
+                    "A03_CROSS_BUCKET_PARENT_INTERSECTION: bucket={bucket} object={object}"
+                );
+            }
+            fixture.policy(PARENT, Fixture::parent_policy(true, true)).await;
+            assert!(
+                !fixture
+                    .allowed(&credential, S3Action::PutObjectAction, "artifacts", &output, None)
+                    .await,
+                "explicit parent Deny remains effective"
+            );
+            fixture.policy(PARENT, Fixture::parent_policy(false, false)).await;
+            assert!(
+                !fixture
+                    .allowed(&credential, S3Action::PutObjectAction, "artifacts", &output, None)
+                    .await,
+                "removing parent output permission remains effective"
+            );
+            assert!(
+                fixture
+                    .allowed(
+                        &credential,
+                        S3Action::GetObjectVersionAction,
+                        "photos",
+                        "input/photo.png",
+                        Some(&fixture.input_version)
+                    )
+                    .await
+            );
+            fixture
+                .iam
+                .revoke_plugin_delegation(PARENT, &record.id)
+                .await
+                .expect("revoke v2");
+            assert!(fixture.issue(&record, &body).await.is_err(), "revoked v2 cannot issue again");
+        },
+    )
+    .await;
+}

rustfs/src/admin/handlers/plugin_delegation.rs

@@ -0,0 +1,624 @@
+// Copyright 2026 RustFS Team
+// SPDX-License-Identifier: Apache-2.0
+
+//! Restriction registration only. These endpoints do not vend credentials.
+use crate::admin::{
+    auth::{AdminResourceScope, validate_admin_action_with_bucket_object_for_iam},
+    plugin_runner::{self, ObjectReference, SubmitRequest},
+    router::{AdminOperation, Operation, S3Router},
+    runtime_sources,
+    storage_api::s3::{self, Body, S3Error, S3ErrorCode, S3Request, S3Response, S3Result},
+};
+use crate::{
+    auth::{check_key_valid_with_context, get_session_token},
+    server::{ADMIN_PREFIX, RemoteAddr},
+};
+use http::{HeaderMap, HeaderValue, Method, StatusCode};
+use matchit::Params;
+use rustfs_iam::delegation::{DelegationError, Restrictions};
+use rustfs_policy::policy::action::{Action, AdminAction};
+use serde::Deserialize;
+use std::time::{Duration, SystemTime, UNIX_EPOCH};
+
+pub fn register_plugin_delegation_route(router: &mut S3Router<AdminOperation>) -> std::io::Result<()> {
+    router.insert(Method::POST, &format!("{ADMIN_PREFIX}/v3/plugin-delegations"), AdminOperation(&Create))?;
+    router.insert(Method::GET, &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}"), AdminOperation(&Get))?;
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/revoke"),
+        AdminOperation(&Revoke),
+    )?;
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/submit"),
+        AdminOperation(&Submit),
+    )?;
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/runs/query"),
+        AdminOperation(&QueryRun),
+    )?;
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/runs/history"),
+        AdminOperation(&HistoryRun),
+    )?;
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/runs/cancel"),
+        AdminOperation(&CancelRun),
+    )?;
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/runs/page"),
+        AdminOperation(&PageRuns),
+    )?;
+    router.insert(
+        Method::POST,
+        &format!("{ADMIN_PREFIX}/v3/plugin-delegations/{{id}}/runs/replay"),
+        AdminOperation(&ReplayRun),
+    )?;
+    Ok(())
+}
+
+pub(super) fn storage_error(error: DelegationError) -> S3Error {
+    match error {
+        DelegationError::Invalid => s3::error(S3ErrorCode::InvalidRequest, "invalid delegation restriction"),
+        DelegationError::NotFound | DelegationError::OwnerRejected => s3::error(S3ErrorCode::NoSuchKey, "delegation not found"),
+        DelegationError::Unavailable => s3::error(S3ErrorCode::InternalError, "delegation unavailable"),
+        _ => s3::error(S3ErrorCode::AccessDenied, "delegation rejected"),
+    }
+}
+
+pub(super) async fn owner(
+    req: &S3Request<Body>,
+    action: AdminAction,
+) -> S3Result<(std::sync::Arc<rustfs_iam::sys::IamSys<rustfs_iam::store::object::ObjectStore>>, String)> {
+    let signed = req
+        .credentials
+        .as_ref()
+        .ok_or_else(|| s3::error(S3ErrorCode::AccessDenied, "authentication required"))?;
+    if get_session_token(&req.uri, &req.headers).is_some() {
+        return Err(s3::error(S3ErrorCode::AccessDenied, "original user required"));
+    }
+    let context = runtime_sources::app_context_from_req(req)
+        .ok_or_else(|| s3::error(S3ErrorCode::InternalError, "application context unavailable"))?;
+    let (credentials, root) = check_key_valid_with_context("", &signed.access_key, Some(context.as_ref())).await?;
+    if root || credentials.is_temp() || credentials.is_service_account() {
+        return Err(s3::error(S3ErrorCode::AccessDenied, "original user required"));
+    }
+    if !context.iam().is_ready() {
+        return Err(s3::error(S3ErrorCode::InternalError, "iam unavailable"));
+    }
+    let iam = context.iam().handle();
+    validate_admin_action_with_bucket_object_for_iam(
+        iam.clone(),
+        &req.headers,
+        &credentials,
+        false,
+        Action::AdminAction(action),
+        req.extensions.get::<Option<RemoteAddr>>().and_then(|a| a.map(|a| a.0)),
+        AdminResourceScope::bucket_object("", ""),
+    )
+    .await?;
+    Ok((iam, credentials.access_key))
+}
+
+pub(super) fn response<T: serde::Serialize>(value: &T) -> S3Result<S3Response<(StatusCode, Body)>> {
+    let bytes =
+        serde_json::to_vec(value).map_err(|_| s3::error(S3ErrorCode::InternalError, "delegation response unavailable"))?;
+    let mut headers = HeaderMap::new();
+    headers.insert(http::header::CONTENT_TYPE, HeaderValue::from_static("application/json"));
+    headers.insert(http::header::CACHE_CONTROL, HeaderValue::from_static("no-store"));
+    Ok(S3Response::with_headers((StatusCode::OK, Body::from(bytes)), headers))
+}
+
+struct Create;
+#[async_trait::async_trait]
+impl Operation for Create {
+    async fn call(&self, mut req: S3Request<Body>, _params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, owner) = owner(&req, AdminAction::CreatePluginDelegationAction).await?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "delegation body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "delegation body unavailable"))?;
+        let restriction: Restrictions = serde_json::from_slice(&bytes)
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid delegation restriction"))?;
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .map_err(|_| s3::error(S3ErrorCode::InternalError, "clock unavailable"))?
+            .as_secs();
+        let record = iam
+            .create_plugin_delegation(&owner, restriction, now)
+            .await
+            .map_err(storage_error)?;
+        response(&record)
+    }
+}
+
+struct Get;
+#[async_trait::async_trait]
+impl Operation for Get {
+    async fn call(&self, req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, owner) = owner(&req, AdminAction::GetPluginDelegationAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .map_err(|_| s3::error(S3ErrorCode::InternalError, "clock unavailable"))?
+            .as_secs();
+        let record = iam
+            .read_active_plugin_delegation(&owner, id, now)
+            .await
+            .map_err(storage_error)?;
+        response(&record)
+    }
+}
+
+struct Revoke;
+#[async_trait::async_trait]
+impl Operation for Revoke {
+    async fn call(&self, req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, owner) = owner(&req, AdminAction::RevokePluginDelegationAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        iam.revoke_plugin_delegation(&owner, id).await.map_err(storage_error)?;
+        response(&serde_json::json!({"revoked":true,"id":id}))
+    }
+}
+
+#[derive(Deserialize)]
+#[serde(deny_unknown_fields)]
+struct SubmitInput {
+    version: u32,
+    instance_id: String,
+    idempotency_key: String,
+    object: SubmitObject,
+}
+
+#[derive(Deserialize)]
+#[serde(deny_unknown_fields)]
+struct SubmitObject {
+    bucket: String,
+    key: String,
+    version_id: String,
+}
+
+struct Submit;
+#[async_trait::async_trait]
+impl Operation for Submit {
+    async fn call(&self, mut req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, signer) = owner(&req, AdminAction::SubmitPluginJobAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "submit body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "submit body unavailable"))?;
+        let input: SubmitInput =
+            serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid submit request"))?;
+        if input.version != 1
+            || !plugin_runner::literal(&input.instance_id)
+            || !plugin_runner::valid_idempotency_key(&input.idempotency_key)
+        {
+            return Err(s3::error(S3ErrorCode::InvalidRequest, "invalid submit request"));
+        }
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .map_err(|_| s3::error(S3ErrorCode::InternalError, "clock unavailable"))?
+            .as_secs();
+        let record = iam
+            .read_active_plugin_delegation(&signer, id, now)
+            .await
+            .map_err(storage_error)?;
+        let deployment = plugin_runner::configured_deployment()?;
+        if !plugin_runner::validate_delegation_scope(
+            &record,
+            &signer,
+            id,
+            &deployment,
+            ObjectReference {
+                bucket: &input.object.bucket,
+                key: &input.object.key,
+                version_id: &input.object.version_id,
+            },
+            now,
+        ) {
+            return Err(s3::error(S3ErrorCode::AccessDenied, "submit restriction rejected"));
+        }
+        let receipt = plugin_runner::submit(&SubmitRequest {
+            version: input.version,
+            instance_id: &input.instance_id,
+            idempotency_key: &input.idempotency_key,
+            object: ObjectReference {
+                bucket: &input.object.bucket,
+                key: &input.object.key,
+                version_id: &input.object.version_id,
+            },
+            delegation_id: &record.id,
+            delegation_revision: &record.revision,
+            actual_signer_access_key: &signer,
+        })
+        .await?;
+        response(&receipt)
+    }
+}
+
+#[derive(Deserialize)]
+#[serde(deny_unknown_fields)]
+struct QueryRunInput {
+    version: u32,
+    run_id: uuid::Uuid,
+}
+
+struct QueryRun;
+#[async_trait::async_trait]
+impl Operation for QueryRun {
+    async fn call(&self, mut req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, signer) = owner(&req, AdminAction::GetPluginRunAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "query body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "query body unavailable"))?;
+        let input: QueryRunInput =
+            serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid query request"))?;
+        if input.version != 1 || input.run_id.is_nil() {
+            return Err(s3::error(S3ErrorCode::InvalidRequest, "invalid query request"));
+        }
+        let record = iam.read_owned_plugin_delegation(&signer, id).await.map_err(storage_error)?;
+        let result = plugin_runner::query(&plugin_runner::QueryRequest {
+            version: input.version,
+            run_id: input.run_id,
+            delegation_id: &record.id,
+            delegation_revision: &record.revision,
+            actual_signer_access_key: &signer,
+        })
+        .await?;
+        response(&result)
+    }
+}
+
+#[derive(Deserialize)]
+#[serde(deny_unknown_fields)]
+struct HistoryRunInput {
+    version: u32,
+    run_id: uuid::Uuid,
+}
+
+fn valid_history_run_input(input: &HistoryRunInput) -> bool {
+    input.version == 1 && !input.run_id.is_nil()
+}
+
+struct HistoryRun;
+#[async_trait::async_trait]
+impl Operation for HistoryRun {
+    async fn call(&self, mut req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, signer) = owner(&req, AdminAction::ListPluginRunsAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "history body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "history body unavailable"))?;
+        let input: HistoryRunInput =
+            serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid history request"))?;
+        if !valid_history_run_input(&input) {
+            return Err(s3::error(S3ErrorCode::InvalidRequest, "invalid history request"));
+        }
+        let record = iam.read_owned_plugin_delegation(&signer, id).await.map_err(storage_error)?;
+        let result = plugin_runner::history(&plugin_runner::HistoryRequest {
+            version: input.version,
+            run_id: input.run_id,
+            delegation_id: &record.id,
+            delegation_revision: &record.revision,
+            actual_signer_access_key: &signer,
+        })
+        .await?;
+        response(&result)
+    }
+}
+
+struct CancelRun;
+#[async_trait::async_trait]
+impl Operation for CancelRun {
+    async fn call(&self, mut req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, signer) = owner(&req, AdminAction::CancelPluginRunAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "cancel body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "cancel body unavailable"))?;
+        let input: QueryRunInput =
+            serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid cancel request"))?;
+        if input.version != 1 || input.run_id.is_nil() {
+            return Err(s3::error(S3ErrorCode::InvalidRequest, "invalid cancel request"));
+        }
+        let record = iam.read_owned_plugin_delegation(&signer, id).await.map_err(storage_error)?;
+        let result = plugin_runner::cancel(&plugin_runner::CancelRequest {
+            version: input.version,
+            run_id: input.run_id,
+            delegation_id: &record.id,
+            delegation_revision: &record.revision,
+            actual_signer_access_key: &signer,
+        })
+        .await?;
+        response(&result)
+    }
+}
+
+#[derive(Deserialize)]
+#[serde(deny_unknown_fields)]
+struct PageRunsInput {
+    version: u32,
+    limit: u32,
+    #[serde(default)]
+    cursor: Option<plugin_runner::RunPageCursor>,
+}
+
+fn valid_page_runs_input(input: &PageRunsInput) -> bool {
+    input.version == 1 && (1..=100).contains(&input.limit) && !input.cursor.is_some_and(|cursor| cursor.run_id.is_nil())
+}
+
+struct PageRuns;
+#[async_trait::async_trait]
+impl Operation for PageRuns {
+    async fn call(&self, mut req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, signer) = owner(&req, AdminAction::ListPluginRunsAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "page body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "page body unavailable"))?;
+        let input: PageRunsInput =
+            serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid page request"))?;
+        if !valid_page_runs_input(&input) {
+            return Err(s3::error(S3ErrorCode::InvalidRequest, "invalid page request"));
+        }
+        let record = iam.read_owned_plugin_delegation(&signer, id).await.map_err(storage_error)?;
+        let result = plugin_runner::page(&plugin_runner::PageRequest {
+            version: input.version,
+            actual_signer_access_key: &signer,
+            delegation_id: &record.id,
+            delegation_revision: &record.revision,
+            limit: input.limit,
+            cursor: input.cursor,
+        })
+        .await?;
+        response(&result)
+    }
+}
+
+#[derive(Deserialize)]
+#[serde(deny_unknown_fields)]
+struct ReplayRunInput {
+    version: u32,
+    origin_run_id: uuid::Uuid,
+    idempotency_key: String,
+    deadline_unix_micros: i64,
+}
+
+fn valid_replay_run_input(input: &ReplayRunInput) -> bool {
+    input.version == 1
+        && !input.origin_run_id.is_nil()
+        && plugin_runner::valid_idempotency_key(&input.idempotency_key)
+        && input.deadline_unix_micros > 0
+}
+
+struct ReplayRun;
+#[async_trait::async_trait]
+impl Operation for ReplayRun {
+    async fn call(&self, mut req: S3Request<Body>, params: Params<'_, '_>) -> S3Result<S3Response<(StatusCode, Body)>> {
+        let (iam, signer) = owner(&req, AdminAction::ReplayPluginRunAction).await?;
+        let id = params
+            .get("id")
+            .ok_or_else(|| s3::error(S3ErrorCode::InvalidRequest, "delegation id required"))?;
+        let bytes = tokio::time::timeout(Duration::from_secs(10), req.input.store_all_limited(16384))
+            .await
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "replay body unavailable"))?
+            .map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "replay body unavailable"))?;
+        let input: ReplayRunInput =
+            serde_json::from_slice(&bytes).map_err(|_| s3::error(S3ErrorCode::InvalidRequest, "invalid replay request"))?;
+        if !valid_replay_run_input(&input) {
+            return Err(s3::error(S3ErrorCode::InvalidRequest, "invalid replay request"));
+        }
+        let now = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .map_err(|_| s3::error(S3ErrorCode::InternalError, "clock unavailable"))?
+            .as_secs();
+        let record = iam
+            .read_active_plugin_delegation(&signer, id, now)
+            .await
+            .map_err(storage_error)?;
+        let result = plugin_runner::replay(&plugin_runner::ReplayRequest {
+            version: input.version,
+            origin_run_id: input.origin_run_id,
+            idempotency_key: &input.idempotency_key,
+            deadline_unix_micros: input.deadline_unix_micros,
+            actual_signer_access_key: &signer,
+            delegation_id: &record.id,
+            delegation_revision: &record.revision,
+        })
+        .await?;
+        response(&result)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    #[tokio::test]
+    async fn delegation_mutations_require_authenticated_original_user() {
+        for operation in 0..8 {
+            let req = S3Request {
+                input: Body::from("{}".to_owned()),
+                method: Method::POST,
+                uri: http::Uri::from_static("/rustfs/admin/v3/plugin-delegations"),
+                headers: HeaderMap::new(),
+                extensions: http::Extensions::new(),
+                credentials: None,
+                region: None,
+                service: None,
+                trailing_headers: None,
+            };
+            let result = if operation == 0 {
+                Get.call(req, Params::new()).await
+            } else if operation == 1 {
+                Revoke.call(req, Params::new()).await
+            } else if operation == 2 {
+                Submit.call(req, Params::new()).await
+            } else if operation == 3 {
+                QueryRun.call(req, Params::new()).await
+            } else if operation == 4 {
+                HistoryRun.call(req, Params::new()).await
+            } else if operation == 5 {
+                CancelRun.call(req, Params::new()).await
+            } else if operation == 6 {
+                PageRuns.call(req, Params::new()).await
+            } else if operation == 7 {
+                ReplayRun.call(req, Params::new()).await
+            } else {
+                Create.call(req, Params::new()).await
+            };
+            let error = result.expect_err("unsigned mutations must not reach persistence");
+            assert_eq!(error.code(), &S3ErrorCode::AccessDenied);
+        }
+    }
+
+    #[test]
+    fn submit_dto_rejects_client_authority_fields_and_null_versions() {
+        assert!(serde_json::from_str::<SubmitInput>(
+            r#"{"version":1,"instance_id":"img","idempotency_key":"k","object":{"bucket":"b","key":"k","version_id":"v"},"actual_signer_access_key":"forged"}"#
+        )
+        .is_err());
+        let input: SubmitInput = serde_json::from_str(
+            r#"{"version":1,"instance_id":"img","idempotency_key":"k","object":{"bucket":"b","key":"a/x","version_id":"null"}}"#,
+        )
+        .unwrap();
+        let record = rustfs_iam::delegation::Delegation {
+            version: 1,
+            id: "a".repeat(32),
+            revision: "a".repeat(32),
+            owner_access_key: "owner".into(),
+            created_at_unix_seconds: 1,
+            restrictions: Restrictions {
+                version: None,
+                output_bucket: None,
+                deployment: "prod".into(),
+                bucket: "b".into(),
+                input_prefix: "a/".into(),
+                output_prefix: "out/".into(),
+                expires_at_unix_seconds: 100,
+            },
+        };
+        assert!(!plugin_runner::validate_delegation_scope(
+            &record,
+            "owner",
+            &record.id,
+            "prod",
+            ObjectReference {
+                bucket: &input.object.bucket,
+                key: &input.object.key,
+                version_id: &input.object.version_id,
+            },
+            2,
+        ));
+    }
+
+    #[test]
+    fn query_run_dto_rejects_client_authority_fields() {
+        let run_id = uuid::Uuid::from_u128(1);
+        let input: QueryRunInput =
+            serde_json::from_str(&format!(r#"{{"version":1,"run_id":"{run_id}"}}"#)).expect("valid run query");
+        assert_eq!(input.run_id, run_id);
+        assert!(
+            serde_json::from_str::<QueryRunInput>(&format!(
+                r#"{{"version":1,"run_id":"{run_id}","actual_signer_access_key":"forged"}}"#
+            ))
+            .is_err()
+        );
+    }
+
+    #[test]
+    fn history_run_dto_is_strict_and_rejects_nil_run() {
+        let run_id = uuid::Uuid::from_u128(1);
+        let input: HistoryRunInput =
+            serde_json::from_str(&format!(r#"{{"version":1,"run_id":"{run_id}"}}"#)).expect("valid history request");
+        assert!(valid_history_run_input(&input));
+        for raw in [
+            r#"{"version":1,"run_id":"00000000-0000-0000-0000-000000000000"}"#,
+            r#"{"version":2,"run_id":"00000000-0000-0000-0000-000000000001"}"#,
+            r#"{"version":1,"run_id":"00000000-0000-0000-0000-000000000001","actual_signer_access_key":"forged"}"#,
+        ] {
+            let rejected = match serde_json::from_str::<HistoryRunInput>(raw) {
+                Ok(input) => !valid_history_run_input(&input),
+                Err(_) => true,
+            };
+            assert!(rejected, "accepted invalid history request: {raw}");
+        }
+    }
+
+    #[test]
+    fn page_runs_dto_is_strict_and_bounded() {
+        let cursor = plugin_runner::RunPageCursor {
+            created_at_unix_micros: 10,
+            run_id: uuid::Uuid::from_u128(1),
+        };
+        let input: PageRunsInput = serde_json::from_str(
+            r#"{"version":1,"limit":100,"cursor":{"created_at_unix_micros":10,"run_id":"00000000-0000-0000-0000-000000000001"}}"#,
+        )
+        .expect("valid page request");
+        assert_eq!(input.cursor, Some(cursor));
+        for raw in [
+            r#"{"version":1,"limit":0}"#,
+            r#"{"version":1,"limit":101}"#,
+            r#"{"version":1,"limit":1,"unknown":true}"#,
+            r#"{"version":1,"limit":1,"actual_signer_access_key":"forged"}"#,
+            r#"{"version":1,"limit":1,"cursor":{"created_at_unix_micros":10,"run_id":"00000000-0000-0000-0000-000000000000"}}"#,
+        ] {
+            let rejected = match serde_json::from_str::<PageRunsInput>(raw) {
+                Ok(input) => !valid_page_runs_input(&input),
+                Err(_) => true,
+            };
+            assert!(rejected, "accepted invalid page request: {raw}");
+        }
+    }
+
+    #[test]
+    fn replay_run_dto_is_strict_and_bounded() {
+        let run_id = uuid::Uuid::from_u128(1);
+        let input: ReplayRunInput = serde_json::from_str(&format!(
+            r#"{{"version":1,"origin_run_id":"{run_id}","idempotency_key":"retry-1","deadline_unix_micros":123}}"#
+        ))
+        .expect("valid replay request");
+        assert!(valid_replay_run_input(&input));
+        for raw in [
+            r#"{"version":1,"origin_run_id":"00000000-0000-0000-0000-000000000000","idempotency_key":"k","deadline_unix_micros":123}"#.to_string(),
+            format!(r#"{{"version":1,"origin_run_id":"{run_id}","idempotency_key":"","deadline_unix_micros":123}}"#),
+            format!(r#"{{"version":1,"origin_run_id":"{run_id}","idempotency_key":"k","deadline_unix_micros":0}}"#),
+            format!(
+                r#"{{"version":1,"origin_run_id":"{run_id}","idempotency_key":"k","deadline_unix_micros":123,"actual_signer_access_key":"forged"}}"#
+            ),
+            format!(
+                r#"{{"version":1,"origin_run_id":"{run_id}","idempotency_key":"{}","deadline_unix_micros":123}}"#,
+                "x".repeat(1025)
+            ),
+        ] {
+            let rejected = match serde_json::from_str::<ReplayRunInput>(&raw) {
+                Ok(input) => !valid_replay_run_input(&input),
+                Err(_) => true,
+            };
+            assert!(rejected, "accepted invalid replay request: {raw}");
+        }
+    }
+}

rustfs/src/admin/mod.rs

@@ -17,6 +17,7 @@ mod auth;
 pub mod console;
 pub mod handlers;
 mod plugin_contract;
+pub(crate) mod plugin_runner;
 pub(crate) mod replication_metrics_wire;
 // Contract inventory is validated by tests before later runtime integration.
 pub(crate) mod route_policy;
@@ -64,6 +65,8 @@ pub fn make_admin_route(
 fn register_admin_routes(r: &mut S3Router<AdminOperation>) -> std::io::Result<()> {
     health::register_health_route(r)?;
     sts::register_admin_auth_route(r)?;
+    handlers::plugin_delegation::register_plugin_delegation_route(r)?;
+    handlers::plugin_attempt::register_plugin_attempt_route(r)?;
 
     account::register_account_route(r)?;
     mfa::register_mfa_route(r)?;

rustfs/src/admin/route_policy.rs

@@ -25,6 +25,15 @@ const TLS_CERTIFICATE_PUBLISH: AdminActionRef = AdminActionRef::new("TLSCertific
 const TLS_CERTIFICATE_STATUS: AdminActionRef = AdminActionRef::new("TLSCertificateStatusAdminAction");
 const CONSOLE_LOG: AdminActionRef = AdminActionRef::new("ConsoleLogAdminAction");
 const COMMIT_TABLE: AdminActionRef = AdminActionRef::new("CommitTableAction");
+const ISSUE_PLUGIN_ATTEMPT: AdminActionRef = AdminActionRef::new("IssuePluginAttemptAction");
+const SUBMIT_PLUGIN_JOB: AdminActionRef = AdminActionRef::new("SubmitPluginJobAction");
+const GET_PLUGIN_RUN: AdminActionRef = AdminActionRef::new("GetPluginRunAction");
+const CANCEL_PLUGIN_RUN: AdminActionRef = AdminActionRef::new("CancelPluginRunAction");
+const LIST_PLUGIN_RUNS: AdminActionRef = AdminActionRef::new("ListPluginRunsAction");
+const REPLAY_PLUGIN_RUN: AdminActionRef = AdminActionRef::new("ReplayPluginRunAction");
+const GET_PLUGIN_DELEGATION: AdminActionRef = AdminActionRef::new("GetPluginDelegationAction");
+const CREATE_PLUGIN_DELEGATION: AdminActionRef = AdminActionRef::new("CreatePluginDelegationAction");
+const REVOKE_PLUGIN_DELEGATION: AdminActionRef = AdminActionRef::new("RevokePluginDelegationAction");
 const CREATE_POLICY: AdminActionRef = AdminActionRef::new("CreatePolicyAdminAction");
 const CREATE_USER: AdminActionRef = AdminActionRef::new("CreateUserAdminAction");
 const CREATE_SERVICE_ACCOUNT: AdminActionRef = AdminActionRef::new("CreateServiceAccountAdminAction");
@@ -656,6 +665,66 @@ pub const ADMIN_ROUTE_POLICY_SPECS: &[AdminRouteSpec] = &[
         SERVER_INFO,
         RouteRiskLevel::Sensitive,
     ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/issue-attempt",
+        ISSUE_PLUGIN_ATTEMPT,
+        RouteRiskLevel::High,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/submit",
+        SUBMIT_PLUGIN_JOB,
+        RouteRiskLevel::High,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/runs/query",
+        GET_PLUGIN_RUN,
+        RouteRiskLevel::Sensitive,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/runs/history",
+        LIST_PLUGIN_RUNS,
+        RouteRiskLevel::Sensitive,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/runs/cancel",
+        CANCEL_PLUGIN_RUN,
+        RouteRiskLevel::Sensitive,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/runs/page",
+        LIST_PLUGIN_RUNS,
+        RouteRiskLevel::Sensitive,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/runs/replay",
+        REPLAY_PLUGIN_RUN,
+        RouteRiskLevel::Sensitive,
+    ),
+    admin(
+        HttpMethod::Get,
+        "/rustfs/admin/v3/plugin-delegations/{id}",
+        GET_PLUGIN_DELEGATION,
+        RouteRiskLevel::Sensitive,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations",
+        CREATE_PLUGIN_DELEGATION,
+        RouteRiskLevel::High,
+    ),
+    admin(
+        HttpMethod::Post,
+        "/rustfs/admin/v3/plugin-delegations/{id}/revoke",
+        REVOKE_PLUGIN_DELEGATION,
+        RouteRiskLevel::High,
+    ),
     admin(
         HttpMethod::Get,
         "/rustfs/admin/v4/plugins/catalog",
@@ -1933,6 +2002,72 @@ mod tests {
         assert!(validate_admin_route_policy_specs().is_ok());
     }
 
+    #[test]
+    fn plugin_submit_route_is_registered_as_high_risk_authenticated_action() {
+        let path = "/rustfs/admin/v3/plugin-delegations/{id}/submit";
+        assert_action(HttpMethod::Post, path, SUBMIT_PLUGIN_JOB);
+        let spec = ADMIN_ROUTE_POLICY_SPECS
+            .iter()
+            .find(|spec| spec.method() == HttpMethod::Post && spec.path() == path)
+            .expect("submit route policy");
+        assert_eq!(spec.risk_level(), RouteRiskLevel::High);
+    }
+
+    #[test]
+    fn plugin_run_query_route_uses_dedicated_authenticated_action() {
+        let path = "/rustfs/admin/v3/plugin-delegations/{id}/runs/query";
+        assert_action(HttpMethod::Post, path, GET_PLUGIN_RUN);
+        let spec = ADMIN_ROUTE_POLICY_SPECS
+            .iter()
+            .find(|spec| spec.method() == HttpMethod::Post && spec.path() == path)
+            .expect("plugin run query route policy");
+        assert_eq!(spec.risk_level(), RouteRiskLevel::Sensitive);
+    }
+
+    #[test]
+    fn plugin_run_history_route_uses_list_action() {
+        let path = "/rustfs/admin/v3/plugin-delegations/{id}/runs/history";
+        assert_action(HttpMethod::Post, path, LIST_PLUGIN_RUNS);
+        let spec = ADMIN_ROUTE_POLICY_SPECS
+            .iter()
+            .find(|spec| spec.method() == HttpMethod::Post && spec.path() == path)
+            .expect("plugin run history route policy");
+        assert_eq!(spec.risk_level(), RouteRiskLevel::Sensitive);
+    }
+
+    #[test]
+    fn plugin_run_cancel_route_uses_dedicated_authenticated_action() {
+        let path = "/rustfs/admin/v3/plugin-delegations/{id}/runs/cancel";
+        assert_action(HttpMethod::Post, path, CANCEL_PLUGIN_RUN);
+        let spec = ADMIN_ROUTE_POLICY_SPECS
+            .iter()
+            .find(|spec| spec.method() == HttpMethod::Post && spec.path() == path)
+            .expect("plugin run cancel route policy");
+        assert_eq!(spec.risk_level(), RouteRiskLevel::Sensitive);
+    }
+
+    #[test]
+    fn plugin_run_page_route_uses_dedicated_authenticated_action() {
+        let path = "/rustfs/admin/v3/plugin-delegations/{id}/runs/page";
+        assert_action(HttpMethod::Post, path, LIST_PLUGIN_RUNS);
+        let spec = ADMIN_ROUTE_POLICY_SPECS
+            .iter()
+            .find(|spec| spec.method() == HttpMethod::Post && spec.path() == path)
+            .expect("plugin run page route policy");
+        assert_eq!(spec.risk_level(), RouteRiskLevel::Sensitive);
+    }
+
+    #[test]
+    fn plugin_run_replay_route_uses_dedicated_authenticated_action() {
+        let path = "/rustfs/admin/v3/plugin-delegations/{id}/runs/replay";
+        assert_action(HttpMethod::Post, path, REPLAY_PLUGIN_RUN);
+        let spec = ADMIN_ROUTE_POLICY_SPECS
+            .iter()
+            .find(|spec| spec.method() == HttpMethod::Post && spec.path() == path)
+            .expect("plugin run replay route policy");
+        assert_eq!(spec.risk_level(), RouteRiskLevel::Sensitive);
+    }
+
     #[test]
     fn route_policy_inventory_has_no_internal_overlap() {
         let mut seen = BTreeSet::new();

rustfs/src/admin/route_registration_test.rs

@@ -116,6 +116,48 @@ fn registered_admin_router() -> S3Router<AdminOperation> {
 
 fn expected_admin_route_matrix() -> Vec<RouteMatrixEntry> {
     vec![
+        admin_route(Method::POST, "/v3/plugin-delegations"),
+        admin_route_sample(Method::GET, "/v3/plugin-delegations/{id}", "/v3/plugin-delegations/test-delegation"),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/revoke",
+            "/v3/plugin-delegations/test-delegation/revoke",
+        ),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/submit",
+            "/v3/plugin-delegations/test-delegation/submit",
+        ),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/runs/query",
+            "/v3/plugin-delegations/test-delegation/runs/query",
+        ),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/runs/history",
+            "/v3/plugin-delegations/test-delegation/runs/history",
+        ),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/runs/cancel",
+            "/v3/plugin-delegations/test-delegation/runs/cancel",
+        ),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/runs/page",
+            "/v3/plugin-delegations/test-delegation/runs/page",
+        ),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/runs/replay",
+            "/v3/plugin-delegations/test-delegation/runs/replay",
+        ),
+        admin_route_sample(
+            Method::POST,
+            "/v3/plugin-delegations/{id}/issue-attempt",
+            "/v3/plugin-delegations/test-delegation/issue-attempt",
+        ),
         route(Method::GET, HEALTH_PREFIX),
         route(Method::HEAD, HEALTH_PREFIX),
         route(Method::GET, HEALTH_READY_PATH),

rustfs/src/app/multipart_usecase.rs

@@ -73,14 +73,15 @@ use super::trailer_adapter::trailer_source;
 use crate::app::object::{
     ConcurrencyManager, ForegroundWriteAdmission, get_concurrency_manager, guard_put_object_body_read_timeout,
     put_object_body_read_timeout, reject_non_wildcard_write_if_none_match, reject_oversize_single_upload,
+    reject_veeam_sosapi_mutation,
 };
 use crate::app::object_data_cache::{
     ObjectDataCacheAdapter, invalidate_object_data_cache_after_complete_multipart_success,
     invalidate_object_data_cache_before_mutation,
 };
 use crate::app::object_usecase::{
-    acquire_copy_bucket_lifecycle_locks, apply_quota_admission, build_put_like_object_lock_metadata, map_quota_check_outcome,
-    s3s_body_error_to_io, validate_existing_object_lock_for_write,
+    apply_quota_admission, build_put_like_object_lock_metadata, map_quota_check_outcome, s3s_body_error_to_io,
+    validate_existing_object_lock_for_write,
 };
 use crate::app::runtime_sources::{
     AppContext, current_app_context, current_object_data_cache_for_context, current_object_store_handle_for_context,
@@ -542,6 +543,8 @@ impl DefaultMultipartUsecase {
             bucket, key, upload_id, ..
         } = req.input;
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
+
         let Some(store) = self.object_store() else {
             return Err(S3Error::with_message(S3ErrorCode::InternalError, "Not init".to_string()));
         };
@@ -610,6 +613,7 @@ impl DefaultMultipartUsecase {
             ..
         } = input;
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
         reject_non_wildcard_write_if_none_match(if_none_match.as_ref(), &req.headers)?;
         validate_table_catalog_object_mutation(&bucket, &key).await?;
 
@@ -1020,6 +1024,7 @@ impl DefaultMultipartUsecase {
             return Err(s3_error!(InvalidStorageClass));
         }
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
         validate_table_catalog_object_mutation(&bucket, &key).await?;
 
         let Some(store) = self.object_store() else {
@@ -1243,6 +1248,7 @@ impl DefaultMultipartUsecase {
 
         let part_id = parse_upload_part_number(part_number)?;
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
         validate_table_catalog_object_mutation(&bucket, &key).await?;
 
         let size = resolve_upload_part_size(content_length, body.as_ref())?;
@@ -1641,6 +1647,7 @@ impl DefaultMultipartUsecase {
             ..
         } = req.input;
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
         let params = parse_list_parts_params(part_number_marker, max_parts)?;
 
         let Some(store) = self.object_store() else {
@@ -1702,6 +1709,7 @@ impl DefaultMultipartUsecase {
             ..
         } = req.input;
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
         let (src_bucket, src_key, raw_src_version_id) = match copy_source {
             CopySource::AccessPoint { .. } => return Err(s3_error!(NotImplemented)),
             CopySource::Outpost { .. } => return Err(s3_error!(NotImplemented)),
@@ -1727,23 +1735,20 @@ impl DefaultMultipartUsecase {
             return Err(S3Error::with_message(S3ErrorCode::InternalError, "Not init".to_string()));
         };
 
-        let (source_bucket_lifecycle_guard, destination_bucket_lifecycle_guard_storage) =
-            acquire_copy_bucket_lifecycle_locks(store.as_ref(), &src_bucket, &bucket).await?;
-        let current_source_incarnation_id = store
-            .bucket_incarnation_id_from_disk(&src_bucket)
+        let (
+            source_bucket_lifecycle_guard,
+            current_source_incarnation_id,
+            destination_bucket_lifecycle_guard_storage,
+            current_destination_incarnation_id,
+        ) = store
+            .acquire_copy_bucket_incarnation_fences(
+                &src_bucket,
+                expected_source_incarnation_id,
+                &bucket,
+                expected_destination_incarnation_id,
+            )
             .await
             .map_err(ApiError::from)?;
-        if expected_source_incarnation_id.is_some_and(|expected| expected != current_source_incarnation_id) {
-            return Err(ApiError::from(StorageError::BucketNotFound(src_bucket.clone())).into());
-        }
-        let current_destination_incarnation_id = if src_bucket == bucket {
-            current_source_incarnation_id
-        } else {
-            store.bucket_incarnation_id_from_disk(&bucket).await.map_err(ApiError::from)?
-        };
-        if expected_destination_incarnation_id.is_some_and(|expected| expected != current_destination_incarnation_id) {
-            return Err(ApiError::from(StorageError::BucketNotFound(bucket.clone())).into());
-        }
         let destination_bucket_lifecycle_guard = destination_bucket_lifecycle_guard_storage
             .as_ref()
             .unwrap_or(&source_bucket_lifecycle_guard);
@@ -1762,9 +1767,9 @@ impl DefaultMultipartUsecase {
             ..Default::default()
         };
         if src_bucket != bucket {
-            dst_opts.add_bucket_lifecycle_lock_guard(&source_bucket_lifecycle_guard);
+            source_bucket_lifecycle_guard.attach_to_object_options(&mut dst_opts);
         }
-        dst_opts.add_bucket_lifecycle_lock_guard(destination_bucket_lifecycle_guard);
+        destination_bucket_lifecycle_guard.attach_to_object_options(&mut dst_opts);
 
         let mp_info = store
             .get_multipart_info(&bucket, &key, &upload_id, &dst_opts)

rustfs/src/app/object/copy.rs

@@ -124,48 +124,6 @@ where
         .map_err(|err| ApiError::from(copy_namespace_lock_error(bucket, &object, "write", err)).into())
 }
 
-pub(crate) async fn acquire_copy_bucket_lifecycle_lock<S>(store: &S, bucket: &str) -> S3Result<NamespaceLockGuard>
-where
-    S: NamespaceLocking<Error = EcstoreError, NamespaceLock = rustfs_lock::NamespaceLockWrapper> + ?Sized,
-{
-    let lock = store
-        .new_ns_lock(bucket, BUCKET_LIFECYCLE_LOCK_OBJECT)
-        .await
-        .map_err(ApiError::from)?;
-    lock.get_read_lock(get_lock_acquire_timeout()).await.map_err(|err| {
-        ApiError::from(copy_namespace_lock_error(
-            bucket,
-            BUCKET_LIFECYCLE_LOCK_OBJECT,
-            "bucket_lifecycle_read",
-            err,
-        ))
-        .into()
-    })
-}
-
-pub(crate) async fn acquire_copy_bucket_lifecycle_locks<S>(
-    store: &S,
-    source_bucket: &str,
-    destination_bucket: &str,
-) -> S3Result<(NamespaceLockGuard, Option<NamespaceLockGuard>)>
-where
-    S: NamespaceLocking<Error = EcstoreError, NamespaceLock = rustfs_lock::NamespaceLockWrapper> + ?Sized,
-{
-    if source_bucket == destination_bucket {
-        return Ok((acquire_copy_bucket_lifecycle_lock(store, source_bucket).await?, None));
-    }
-
-    if source_bucket < destination_bucket {
-        let source_guard = acquire_copy_bucket_lifecycle_lock(store, source_bucket).await?;
-        let destination_guard = acquire_copy_bucket_lifecycle_lock(store, destination_bucket).await?;
-        Ok((source_guard, Some(destination_guard)))
-    } else {
-        let destination_guard = acquire_copy_bucket_lifecycle_lock(store, destination_bucket).await?;
-        let source_guard = acquire_copy_bucket_lifecycle_lock(store, source_bucket).await?;
-        Ok((source_guard, Some(destination_guard)))
-    }
-}
-
 impl DefaultObjectUsecase {
     pub fn execute_copy_object(
         &self,
@@ -281,6 +239,7 @@ impl DefaultObjectUsecase {
         // Validate both source and destination keys
         validate_object_key(&src_key, "COPY (source)")?;
         validate_object_key(&key, "COPY (dest)")?;
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
         validate_table_catalog_object_mutation(&bucket, &key).await?;
         let replaces_metadata = match metadata_directive.as_ref().map(|directive| directive.as_str()) {
             None | Some(MetadataDirective::COPY) => false,
@@ -383,29 +342,20 @@ impl DefaultObjectUsecase {
         let Some(store) = self.object_store() else {
             return Err(S3Error::with_message(S3ErrorCode::InternalError, "Not init".to_string()));
         };
-        let (source_bucket_lifecycle_guard, destination_bucket_lifecycle_guard_storage) =
-            acquire_copy_bucket_lifecycle_locks(store.as_ref(), &src_bucket, &bucket).await?;
-        let current_source_incarnation_id = store
-            .bucket_incarnation_id_from_disk(&src_bucket)
+        let (
+            source_bucket_lifecycle_guard,
+            current_source_incarnation_id,
+            destination_bucket_lifecycle_guard_storage,
+            current_destination_incarnation_id,
+        ) = store
+            .acquire_copy_bucket_incarnation_fences(
+                &src_bucket,
+                src_get_opts.expected_bucket_incarnation_id,
+                &bucket,
+                dst_opts.expected_bucket_incarnation_id,
+            )
             .await
             .map_err(ApiError::from)?;
-        if src_get_opts
-            .expected_bucket_incarnation_id
-            .is_some_and(|expected| expected != current_source_incarnation_id)
-        {
-            return Err(ApiError::from(StorageError::BucketNotFound(src_bucket.clone())).into());
-        }
-        let current_destination_incarnation_id = if src_bucket == bucket {
-            current_source_incarnation_id
-        } else {
-            store.bucket_incarnation_id_from_disk(&bucket).await.map_err(ApiError::from)?
-        };
-        if dst_opts
-            .expected_bucket_incarnation_id
-            .is_some_and(|expected| expected != current_destination_incarnation_id)
-        {
-            return Err(ApiError::from(StorageError::BucketNotFound(bucket.clone())).into());
-        }
         let destination_bucket_lifecycle_guard = destination_bucket_lifecycle_guard_storage
             .as_ref()
             .unwrap_or(&source_bucket_lifecycle_guard);
@@ -422,9 +372,9 @@ impl DefaultObjectUsecase {
         src_get_opts.expected_bucket_incarnation_id = Some(current_source_incarnation_id);
         dst_opts.expected_bucket_incarnation_id = Some(current_destination_incarnation_id);
         if src_bucket != bucket {
-            dst_opts.add_bucket_lifecycle_lock_guard(&source_bucket_lifecycle_guard);
+            source_bucket_lifecycle_guard.attach_to_object_options(&mut dst_opts);
         }
-        dst_opts.add_bucket_lifecycle_lock_guard(destination_bucket_lifecycle_guard);
+        destination_bucket_lifecycle_guard.attach_to_object_options(&mut dst_opts);
 
         // Bucket metadata uses the bucket name as its namespace-lock key. Load
         // every copy-time bucket snapshot before a same-object key can collide
@@ -1081,6 +1031,26 @@ mod tests {
         assert_eq!(err.code(), &S3ErrorCode::InvalidRequest);
     }
 
+    #[tokio::test]
+    async fn copy_object_rejects_reserved_catalog_destination_before_store_lookup() {
+        let input = CopyObjectInput::builder()
+            .copy_source(CopySource::Bucket {
+                bucket: "source-bucket".into(),
+                key: "source-key".into(),
+                version_id: None,
+            })
+            .bucket(format!("missing-{}", Uuid::new_v4()))
+            .key(".rustfs-table/metadata/current.json".to_string())
+            .build()
+            .unwrap();
+        let error = DefaultObjectUsecase::without_context()
+            .execute_copy_object(build_request(input, Method::PUT))
+            .await
+            .expect_err("reserved catalog destination must fail closed without bucket metadata");
+        assert_eq!(error.code(), &S3ErrorCode::InvalidRequest);
+        assert_eq!(error.message(), Some(crate::table_catalog::RESERVED_CATALOG_OBJECT_MESSAGE));
+    }
+
     #[tokio::test]
     async fn execute_copy_object_rejects_invalid_storage_class() {
         let input = CopyObjectInput::builder()

rustfs/src/app/object/delete.rs

@@ -1038,6 +1038,7 @@ impl DefaultObjectUsecase {
 
         // Validate object key
         validate_object_key(&key, "DELETE")?;
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &key).await?;
 
         let replica = req
             .headers

rustfs/src/app/object/extract.rs

@@ -2461,6 +2461,7 @@ impl DefaultObjectUsecase {
             }
             let table_data_plane_publication_guards = retained_table_data_plane_publication_guards(&auth_req);
             drop(auth_req);
+            extract_try!(reject_veeam_sosapi_mutation(|| Some(Arc::clone(&commit_context.store)), &bucket, &fpath).await);
             if archive_entry_mod_time.is_some() {
                 opts.mod_time = archive_entry_mod_time;
             }

rustfs/src/app/object/get.rs

@@ -14,6 +14,7 @@
 
 //! GetObject / GetObjectAttributes read path: cold fill, resume, stream tuning.
 
+use super::veeam_sosapi;
 use super::*;
 use crate::app::storage_api::object_usecase::object_cache::{
     GetObjectReadCondition, GetObjectReadMetadata, evaluate_read_preconditions, has_read_preconditions,
@@ -4145,6 +4146,37 @@ impl DefaultObjectUsecase {
         result
     }
 
+    async fn serve_veeam_sosapi_get(
+        &self,
+        req: &S3Request<GetObjectInput>,
+        store: &Arc<ECStore>,
+        kind: veeam_sosapi::SosapiKind,
+        part_number: Option<usize>,
+        range: Option<&HTTPRangeSpec>,
+    ) -> S3Result<S3Response<GetObjectOutput>> {
+        let representation =
+            veeam_sosapi::read_representation(store, &req.input.bucket, kind, &req.headers, part_number, range).await?;
+        let content_type = ContentType::from_str(veeam_sosapi::CONTENT_TYPE)
+            .map_err(|_| S3Error::with_message(S3ErrorCode::InternalError, "invalid SOSAPI content type"))?;
+        let ranged = representation.content_range.is_some();
+        let output = GetObjectOutput {
+            body: Some(StreamingBlob::from(s3s::Body::from(representation.body))),
+            content_length: Some(representation.content_length),
+            content_type: Some(content_type),
+            content_range: representation.content_range,
+            e_tag: Some(to_s3s_etag(&representation.etag_hex)),
+            last_modified: Some(Timestamp::from(representation.last_modified)),
+            accept_ranges: Some(ACCEPT_RANGES_BYTES.to_string()),
+            ..Default::default()
+        };
+        let mut response = wrap_response_with_cors(&req.input.bucket, &req.method, &req.headers, output).await;
+        inject_accept_ranges_header(&mut response.headers);
+        if ranged {
+            response.status = Some(StatusCode::PARTIAL_CONTENT);
+        }
+        Ok(response)
+    }
+
     async fn execute_get_object_inner(&self, mut req: S3Request<GetObjectInput>) -> S3Result<S3Response<GetObjectOutput>> {
         let helper = OperationHelper::new(&req, EventName::ObjectAccessedGet, S3Operation::GetObject).suppress_event();
 
@@ -4223,6 +4255,26 @@ impl DefaultObjectUsecase {
         }
         record_get_object_s3_handler_stage_duration(GET_OBJECT_STAGE_BUCKET_VALIDATION, bucket_validation_start);
 
+        if validated.version_id.is_none()
+            && let Some(kind) = veeam_sosapi::handled_kind(&validated.key)
+        {
+            let served = self
+                .serve_veeam_sosapi_get(&req, &store, kind, validated.part_number, validated.rs.as_ref())
+                .await;
+            match served {
+                Ok(response) => {
+                    lifecycle.finish_ok();
+                    let result = Ok(response);
+                    let _ = helper.complete(&result);
+                    return result;
+                }
+                Err(err) => {
+                    lifecycle.finish_err();
+                    return Self::complete_get_object_error(helper, err);
+                }
+            }
+        }
+
         let request_context_start = stage_metrics_enabled.then(std::time::Instant::now);
         let request_context = match Self::prepare_get_object_request_context(validated, &req.headers).await {
             Ok(request_context) => request_context,

rustfs/src/app/object/head.rs

@@ -14,6 +14,7 @@
 
 //! HeadObject path.
 
+use super::veeam_sosapi;
 use super::*;
 use crate::on_demand_migration::{
     BucketOdmState, HeadPolicy, OdmLookup, OdmOp, OdmOutcome, OnDemandMigrationSys, SourceClient, SourceError, SourceHead,
@@ -298,6 +299,40 @@ impl DefaultObjectUsecase {
         }
     }
 
+    async fn serve_veeam_sosapi_head(
+        &self,
+        req: &S3Request<HeadObjectInput>,
+        store: &Arc<ECStore>,
+        kind: veeam_sosapi::SosapiKind,
+        part_number: Option<usize>,
+        range: Option<&HTTPRangeSpec>,
+    ) -> S3Result<S3Response<HeadObjectOutput>> {
+        let representation =
+            veeam_sosapi::read_representation(store, &req.input.bucket, kind, &req.headers, part_number, range).await?;
+        let content_type = ContentType::from_str(veeam_sosapi::CONTENT_TYPE)
+            .map_err(|_| S3Error::with_message(S3ErrorCode::InternalError, "invalid SOSAPI content type"))?;
+        let content_range = representation.content_range;
+        let output = HeadObjectOutput {
+            content_length: Some(representation.content_length),
+            content_type: Some(content_type),
+            accept_ranges: Some(ACCEPT_RANGES_BYTES.to_string()),
+            last_modified: Some(Timestamp::from(representation.last_modified)),
+            e_tag: Some(to_s3s_etag(&representation.etag_hex)),
+            ..Default::default()
+        };
+        let mut response = wrap_response_with_cors(&req.input.bucket, &req.method, &req.headers, output).await;
+        inject_accept_ranges_header(&mut response.headers);
+        if let Some(content_range) = content_range {
+            response.headers.insert(
+                http::header::CONTENT_RANGE,
+                HeaderValue::from_str(&content_range)
+                    .map_err(|_| S3Error::with_message(S3ErrorCode::InternalError, "invalid content range"))?,
+            );
+            response.status = Some(StatusCode::PARTIAL_CONTENT);
+        }
+        Ok(response)
+    }
+
     #[instrument(level = "debug", skip(self, req))]
     pub async fn execute_head_object(&self, mut req: S3Request<HeadObjectInput>) -> S3Result<S3Response<HeadObjectOutput>> {
         if let Some(context) = &self.context {
@@ -336,6 +371,17 @@ impl DefaultObjectUsecase {
         };
         validate_bucket_exists(&store, &bucket).await?;
 
+        if version_id.is_none()
+            && let Some(kind) = veeam_sosapi::handled_kind(&key)
+        {
+            let response = self
+                .serve_veeam_sosapi_head(&req, &store, kind, part_number, rs.as_ref())
+                .await?;
+            let result = Ok(response);
+            let _ = helper.complete(&result);
+            return result;
+        }
+
         let opts: ObjectOptions = get_opts(&bucket, &key, version_id, part_number, &req.headers)
             .await
             .map_err(ApiError::from)?;

rustfs/src/app/object/mod.rs

@@ -134,7 +134,6 @@ use rustfs_config::MI_B;
 use rustfs_filemeta::{NULL_VERSION_ID, RestoreStatusOps, parse_restore_obj_status};
 use rustfs_io_core::{BytesPool, PooledBuffer};
 use rustfs_io_metrics;
-use rustfs_lock::NamespaceLockGuard;
 use rustfs_notify::EventArgsBuilder;
 use rustfs_object_capacity::capacity_manager::get_capacity_manager;
 use rustfs_policy::policy::action::{Action, S3Action};
@@ -220,8 +219,8 @@ mod restore;
 pub(crate) mod shared;
 #[cfg(test)]
 mod test_support;
+mod veeam_sosapi;
 
-pub(crate) use self::copy::*;
 #[cfg(test)]
 pub(crate) use self::delete::*;
 pub(crate) use self::extract::*;
@@ -264,9 +263,8 @@ use tracing::{debug, error, instrument, warn};
 use uuid::Uuid;
 
 use super::storage_api::object_usecase::{
-    BUCKET_LIFECYCLE_LOCK_OBJECT, GetObjectReader, StorageDeletedObject, StorageObjectInfo as ObjectInfo,
-    StorageObjectLockDeleteOptions, StorageObjectOptions as ObjectOptions, StorageObjectToDelete as ObjectToDelete,
-    StoragePutObjReader as PutObjReader,
+    GetObjectReader, StorageDeletedObject, StorageObjectInfo as ObjectInfo, StorageObjectLockDeleteOptions,
+    StorageObjectOptions as ObjectOptions, StorageObjectToDelete as ObjectToDelete, StoragePutObjReader as PutObjReader,
 };
 use crate::app::object_data_cache::{
     ColdFillCoordinateOutcome, ColdFillDiskPermitOwner, ColdFillError, ColdFillProducer, GetObjectBodyCacheLookup,

rustfs/src/app/object/put.rs

@@ -1272,6 +1272,7 @@ impl DefaultObjectUsecase {
                 format!("{RUSTFS_MAX_CONTENT_LENGTH_QUERY} is not supported for archive extraction"),
             ));
         }
+        reject_veeam_sosapi_mutation(|| self.object_store(), req.input.bucket.as_str(), req.input.key.as_str()).await?;
         if is_put_object_extract_requested(&req.headers) && !inbound_replication_put {
             return Box::pin(self.execute_put_object_extract(req)).await;
         }
@@ -1505,6 +1506,8 @@ impl DefaultObjectUsecase {
             sse_customer_key_md5,
         } = sse;
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), bucket.as_str(), key.as_str()).await?;
+
         // The app check preserves the existing S3 error contract; the storage
         // commit path reserves the exact net logical growth under its locks.
         let quota_stage_start = put_stage_metrics_enabled.then(Instant::now);

rustfs/src/app/object/restore.rs

@@ -164,6 +164,7 @@ impl DefaultObjectUsecase {
             ..
         } = req.input.clone();
 
+        reject_veeam_sosapi_mutation(|| self.object_store(), &bucket, &object).await?;
         validate_table_catalog_object_mutation(&bucket, &object).await?;
 
         // Typed S3 errors on every RestoreObject failure (backlog#2205): a
@@ -213,8 +214,8 @@ impl DefaultObjectUsecase {
         // `apply_bucket_generation_guard` deliberately tolerates a missing guard
         // (only the S3 access layer installs one), so this must not hard-require
         // it. Resolve the current generation instead, exactly as the copy path
-        // does. The fence is unaffected: the value is re-read from disk and
-        // compared below, before the restore is admitted.
+        // does. The fence is unaffected: the value is validated under the
+        // lifecycle fence below, before the restore is admitted.
         let restore_bucket_incarnation_id = match opts.expected_bucket_incarnation_id {
             Some(incarnation_id) => incarnation_id,
             None => {
@@ -246,10 +247,12 @@ impl DefaultObjectUsecase {
         // in-flight commit on the same object) is transient — answer 503
         // SlowDown so SDK clients back off and retry instead of treating it
         // as a hard failure.
-        let mut restore_bucket_lifecycle_guard = Some(acquire_copy_bucket_lifecycle_lock(store.as_ref(), &bucket).await?);
-        if store.bucket_incarnation_id_from_disk(&bucket).await.map_err(ApiError::from)? != restore_bucket_incarnation_id {
-            return Err(ApiError::from(StorageError::BucketNotFound(bucket.clone())).into());
-        }
+        let mut restore_bucket_lifecycle_guard = Some(
+            store
+                .acquire_bucket_incarnation_fence(&bucket, restore_bucket_incarnation_id)
+                .await
+                .map_err(ApiError::from)?,
+        );
         let mut accept_guard = {
             let guard = store
                 .acquire_restore_accept_guard(&bucket, &object)
@@ -299,12 +302,12 @@ impl DefaultObjectUsecase {
                             S3Error::with_message(S3ErrorCode::RestoreAlreadyInProgress, "Object restore is already in progress.")
                         })?;
 
-                    restore_bucket_lifecycle_guard = Some(acquire_copy_bucket_lifecycle_lock(store.as_ref(), &bucket).await?);
-                    if store.bucket_incarnation_id_from_disk(&bucket).await.map_err(ApiError::from)?
-                        != restore_bucket_incarnation_id
-                    {
-                        return Err(ApiError::from(StorageError::BucketNotFound(bucket.clone())).into());
-                    }
+                    restore_bucket_lifecycle_guard = Some(
+                        store
+                            .acquire_bucket_incarnation_fence(&bucket, restore_bucket_incarnation_id)
+                            .await
+                            .map_err(ApiError::from)?,
+                    );
                     accept_guard = Some(
                         store
                             .acquire_restore_accept_guard(&bucket, &object)
@@ -398,7 +401,7 @@ impl DefaultObjectUsecase {
                 ..Default::default()
             };
             if let Some(guard) = restore_bucket_lifecycle_guard.as_ref() {
-                restore_dst_opts.add_bucket_lifecycle_lock_guard(guard);
+                guard.attach_to_object_options(&mut restore_dst_opts);
             }
             if let Some(guard) = accept_guard.as_ref() {
                 guard.add_namespace_lock_fence(&mut restore_dst_opts);

rustfs/src/app/object/shared.rs

@@ -562,6 +562,29 @@ pub(super) fn inject_accept_ranges_header(headers: &mut HeaderMap) {
     headers.insert(http::header::ACCEPT_RANGES, HeaderValue::from_static(ACCEPT_RANGES_BYTES));
 }
 
+/// Reject a mutation of a Veeam SOSAPI key while the feature is enabled.
+///
+/// The store closure runs only after the key matches, so ordinary object
+/// writes pay two string compares. Bucket existence is checked first so a
+/// missing bucket stays `NoSuchBucket`.
+pub(crate) async fn reject_veeam_sosapi_mutation(
+    store: impl FnOnce() -> Option<Arc<ECStore>>,
+    bucket: &str,
+    key: &str,
+) -> S3Result<()> {
+    if !super::veeam_sosapi::mutation_blocked(key) {
+        return Ok(());
+    }
+    let Some(store) = store() else {
+        return Err(S3Error::with_message(S3ErrorCode::InternalError, "Not init".to_string()));
+    };
+    validate_bucket_exists(&store, bucket).await?;
+    Err(S3Error::with_message(
+        S3ErrorCode::MethodNotAllowed,
+        "Veeam SOSAPI system objects are read-only",
+    ))
+}
+
 /// Derive the response-header echo pairs for an additional-checksum algorithm
 /// (XXHash3/64/128, SHA-512) from the server-computed content checksum, for
 /// PutObject to echo back (#1256). Returns empty for the five s3s-typed algorithms

rustfs/src/app/object/veeam_sosapi.rs

@@ -0,0 +1,565 @@
+// Copyright 2024 RustFS Team
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+//! Veeam SOSAPI virtual objects.
+//!
+//! Authenticated GET and HEAD of two exact bucket-root keys return generated
+//! XML. The objects are not stored: no `xl.meta`, version, or Object Lock
+//! interaction. Mutations of those keys are rejected while the feature is on.
+
+use std::collections::{HashMap, HashSet};
+use std::future::Future;
+use std::sync::atomic::{AtomicBool, Ordering};
+use std::sync::{Arc, OnceLock};
+use std::time::Duration;
+
+use super::super::storage_api::s3::{S3Error, S3ErrorCode, S3Result};
+use bytes::Bytes;
+use md5::Digest as _;
+use md5::Md5;
+use moka::{future::Cache as AsyncCache, sync::Cache as SyncCache};
+use time::OffsetDateTime;
+use tracing::debug;
+
+use super::super::storage_api::object_usecase::data_usage::load_bucket_usage_from_backend_cached;
+use super::super::storage_api::object_usecase::{ECStore, StorageObjectInfo as ObjectInfo, check_preconditions};
+use super::HTTPRangeSpec;
+use super::shared::{LOG_COMPONENT_APP, LOG_SUBSYSTEM_OBJECT};
+use crate::app::storage_api::admin_usecase::contract::StorageAdminApi;
+use crate::app::storage_api::object_usecase::bucket::quota::{BucketQuota, QuotaType};
+use http::HeaderMap;
+use uuid::Uuid;
+
+pub(super) const SYSTEM_KEY: &str = ".system-d26a9498-cb7c-4a87-a44a-8ae204f5ba6c/system.xml";
+pub(super) const CAPACITY_KEY: &str = ".system-d26a9498-cb7c-4a87-a44a-8ae204f5ba6c/capacity.xml";
+pub(super) const CONTENT_TYPE: &str = "application/xml";
+
+const CAPACITY_XML_CACHE_TTL: Duration = Duration::from_secs(12);
+const CAPACITY_HISTORY_IDLE: Duration = Duration::from_secs(3600);
+const CAPACITY_CACHE_ENTRIES: u64 = 1024;
+const CLUSTER_CACHE_ENTRIES: u64 = 16;
+const MAX_BUCKET_REFRESHES: usize = 64;
+const MAX_CLUSTER_REFRESHES: usize = 16;
+const EVENT_USAGE_MISSING: &str = "veeam_sosapi_usage_missing";
+const EVENT_QUOTA_UNAVAILABLE: &str = "veeam_sosapi_quota_unavailable";
+
+static LOGGED_USAGE_MISSING: AtomicBool = AtomicBool::new(false);
+static LOGGED_QUOTA_UNAVAILABLE: AtomicBool = AtomicBool::new(false);
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub(super) enum SosapiKind {
+    System,
+    Capacity,
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum SosapiReadError {
+    InvalidRange,
+    PartNumber,
+}
+
+pub(super) struct SosapiRepresentation {
+    pub body: Bytes,
+    pub content_length: i64,
+    pub content_range: Option<String>,
+    pub etag_hex: String,
+    pub last_modified: OffsetDateTime,
+}
+
+pub(super) struct CapacityInputs {
+    pub used_bucket: u64,
+    pub hard_quota: Option<u64>,
+    pub capacity_cluster: u64,
+    pub free_cluster: u64,
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub(super) struct CapacityFigures {
+    pub capacity: u64,
+    pub used: u64,
+    pub available: u64,
+}
+
+#[derive(Clone, Debug, Hash, PartialEq, Eq)]
+struct CapacityCacheKey {
+    store_id: Uuid,
+    bucket: String,
+    incarnation: Uuid,
+}
+
+#[derive(Clone)]
+struct CachedXml {
+    bytes: Bytes,
+    etag_hex: String,
+    modified_at: OffsetDateTime,
+}
+
+// Bucket refreshes may wait for a cluster permit; cluster probes never acquire a bucket permit.
+struct CapacityCaches {
+    current: AsyncCache<CapacityCacheKey, CachedXml>,
+    history: SyncCache<CapacityCacheKey, CachedXml>,
+    refresh_permits: tokio::sync::Semaphore,
+}
+
+impl CapacityCaches {
+    fn new() -> Self {
+        Self {
+            current: AsyncCache::builder()
+                .max_capacity(CAPACITY_CACHE_ENTRIES)
+                .time_to_live(CAPACITY_XML_CACHE_TTL)
+                .build(),
+            history: SyncCache::builder()
+                .max_capacity(CAPACITY_CACHE_ENTRIES)
+                .time_to_idle(CAPACITY_HISTORY_IDLE)
+                .build(),
+            refresh_permits: tokio::sync::Semaphore::new(MAX_BUCKET_REFRESHES),
+        }
+    }
+}
+
+struct StableXml {
+    bytes: Bytes,
+    etag_hex: String,
+    modified_at: OffsetDateTime,
+}
+
+pub(super) fn match_sosapi_key(key: &str) -> Option<SosapiKind> {
+    match key {
+        SYSTEM_KEY => Some(SosapiKind::System),
+        CAPACITY_KEY => Some(SosapiKind::Capacity),
+        _ => None,
+    }
+}
+
+pub(super) fn veeam_sosapi_enabled() -> bool {
+    rustfs_utils::get_env_bool(rustfs_config::ENV_VEEAM_SOSAPI_ENABLE, rustfs_config::DEFAULT_VEEAM_SOSAPI_ENABLE)
+}
+
+/// SOSAPI key whose virtual read should run. `None` when the key is ordinary
+/// or the operator turned the feature off.
+pub(super) fn handled_kind(key: &str) -> Option<SosapiKind> {
+    let kind = match_sosapi_key(key)?;
+    veeam_sosapi_enabled().then_some(kind)
+}
+
+/// True only for an exact SOSAPI key while the feature is enabled.
+///
+/// Callers use this on the mutation hot path: a miss is two string compares
+/// and does not read the object store.
+pub(super) fn mutation_blocked(key: &str) -> bool {
+    match_sosapi_key(key).is_some() && veeam_sosapi_enabled()
+}
+
+pub(super) fn capacity_figures(inputs: CapacityInputs) -> CapacityFigures {
+    let used_bucket = inputs.used_bucket;
+    let capacity = inputs
+        .hard_quota
+        .filter(|quota| *quota > 0)
+        .unwrap_or(inputs.capacity_cluster);
+    let used = used_bucket.min(capacity);
+    let available = capacity.saturating_sub(used).min(inputs.free_cluster);
+    CapacityFigures {
+        capacity,
+        used,
+        available,
+    }
+}
+
+/// Full generated document. Range and part-number checks happen after read
+/// preconditions so a failing `If-Match` stays 412.
+async fn generated(store: &Arc<ECStore>, bucket: &str, kind: SosapiKind) -> S3Result<(Bytes, String, OffsetDateTime)> {
+    match kind {
+        SosapiKind::System => {
+            let stable = system_xml_stable();
+            Ok((stable.bytes.clone(), stable.etag_hex.clone(), stable.modified_at))
+        }
+        SosapiKind::Capacity => cached_or_build_capacity(store, bucket).await,
+    }
+}
+
+pub(super) async fn read_representation(
+    store: &Arc<ECStore>,
+    bucket: &str,
+    kind: SosapiKind,
+    headers: &HeaderMap,
+    part_number: Option<usize>,
+    range: Option<&HTTPRangeSpec>,
+) -> S3Result<SosapiRepresentation> {
+    let (full, etag_hex, last_modified) = generated(store, bucket, kind).await?;
+    check_preconditions(
+        headers,
+        &ObjectInfo {
+            etag: Some(etag_hex.clone()),
+            mod_time: Some(last_modified),
+            ..Default::default()
+        },
+    )?;
+    representation_from(full, etag_hex, last_modified, part_number, range).map_err(|err| match err {
+        SosapiReadError::InvalidRange => {
+            S3Error::with_message(S3ErrorCode::InvalidRange, "The requested range is not satisfiable")
+        }
+        SosapiReadError::PartNumber => {
+            S3Error::with_message(S3ErrorCode::InvalidArgument, "partNumber is not supported for Veeam SOSAPI objects")
+        }
+    })
+}
+
+fn representation_from(
+    full: Bytes,
+    etag_hex: String,
+    last_modified: OffsetDateTime,
+    part_number: Option<usize>,
+    range: Option<&HTTPRangeSpec>,
+) -> Result<SosapiRepresentation, SosapiReadError> {
+    if part_number.is_some() {
+        return Err(SosapiReadError::PartNumber);
+    }
+    apply_range(full, etag_hex, last_modified, range)
+}
+
+fn apply_range(
+    full: Bytes,
+    etag_hex: String,
+    last_modified: OffsetDateTime,
+    range: Option<&HTTPRangeSpec>,
+) -> Result<SosapiRepresentation, SosapiReadError> {
+    let total = i64::try_from(full.len()).unwrap_or(i64::MAX);
+    let Some(range) = range else {
+        return Ok(SosapiRepresentation {
+            content_length: total,
+            content_range: None,
+            body: full,
+            etag_hex,
+            last_modified,
+        });
+    };
+    let (start, length) = range.get_offset_length(total).map_err(|_| SosapiReadError::InvalidRange)?;
+    let length_usize = usize::try_from(length).map_err(|_| SosapiReadError::InvalidRange)?;
+    let end = start.checked_add(length_usize).ok_or(SosapiReadError::InvalidRange)?;
+    if end > full.len() {
+        return Err(SosapiReadError::InvalidRange);
+    }
+    let start_i64 = i64::try_from(start).map_err(|_| SosapiReadError::InvalidRange)?;
+    let end_inclusive = start_i64 + length - 1;
+    Ok(SosapiRepresentation {
+        body: full.slice(start..end),
+        content_length: length,
+        content_range: Some(format!("bytes {start_i64}-{end_inclusive}/{total}")),
+        etag_hex,
+        last_modified,
+    })
+}
+
+fn system_xml_stable() -> &'static StableXml {
+    static BODY: OnceLock<StableXml> = OnceLock::new();
+    BODY.get_or_init(|| {
+        let bytes = Bytes::from(system_xml(env!("CARGO_PKG_VERSION")));
+        let etag_hex = md5_hex(&bytes);
+        StableXml {
+            bytes,
+            etag_hex,
+            modified_at: OffsetDateTime::from_unix_timestamp(crate::version::build::BUILD_TIMESTAMP)
+                .unwrap_or(OffsetDateTime::UNIX_EPOCH),
+        }
+    })
+}
+
+fn system_xml(version: &str) -> String {
+    let version = xml_escape_text(version);
+    format!(
+        "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<SystemInfo>\n  <ProtocolVersion>\"1.0\"</ProtocolVersion>\n  <ModelName>\"RustFS {version}\"</ModelName>\n  <ProtocolCapabilities>\n    <CapacityInfo>true</CapacityInfo>\n    <UploadSessions>false</UploadSessions>\n    <IAMSTS>false</IAMSTS>\n  </ProtocolCapabilities>\n</SystemInfo>\n"
+    )
+}
+
+fn capacity_xml(figures: &CapacityFigures) -> String {
+    format!(
+        "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<CapacityInfo>\n  <Capacity>{}</Capacity>\n  <Available>{}</Available>\n  <Used>{}</Used>\n</CapacityInfo>\n",
+        figures.capacity, figures.available, figures.used,
+    )
+}
+
+/// Escape XML text. Quotes stay as ASCII quotes: Veeam's parser requires that
+/// spelling inside `ProtocolVersion` and `ModelName`.
+fn xml_escape_text(value: &str) -> String {
+    let mut escaped = String::with_capacity(value.len());
+    for ch in value.chars() {
+        match ch {
+            '&' => escaped.push_str("&amp;"),
+            '<' => escaped.push_str("&lt;"),
+            '>' => escaped.push_str("&gt;"),
+            _ => escaped.push(ch),
+        }
+    }
+    escaped
+}
+
+fn md5_hex(bytes: &[u8]) -> String {
+    const HEX: &[u8; 16] = b"0123456789abcdef";
+    let digest = Md5::digest(bytes);
+    let mut out = String::with_capacity(32);
+    for byte in digest {
+        out.push(char::from(HEX[usize::from(byte >> 4)]));
+        out.push(char::from(HEX[usize::from(byte & 0x0f)]));
+    }
+    out
+}
+
+fn capacity_caches() -> &'static CapacityCaches {
+    static CACHES: OnceLock<CapacityCaches> = OnceLock::new();
+    CACHES.get_or_init(CapacityCaches::new)
+}
+
+async fn cached_or_build_capacity(store: &Arc<ECStore>, bucket: &str) -> S3Result<(Bytes, String, OffsetDateTime)> {
+    let incarnation = store
+        .bucket_incarnation_id_from_disk(bucket)
+        .await
+        .map_err(|_| capacity_unavailable())?;
+    let key = CapacityCacheKey {
+        store_id: store.id,
+        bucket: bucket.to_owned(),
+        incarnation,
+    };
+    cached_or_load_capacity(capacity_caches(), &key, || async {
+        let inputs = load_capacity_inputs(store, bucket, incarnation).await?;
+        if store
+            .bucket_incarnation_id_from_disk(bucket)
+            .await
+            .map_err(|_| capacity_unavailable())?
+            != incarnation
+        {
+            return Err(capacity_unavailable());
+        }
+        Ok(capacity_figures(inputs))
+    })
+    .await
+}
+
+async fn cached_or_load_capacity<F, Fut>(
+    caches: &CapacityCaches,
+    key: &CapacityCacheKey,
+    load: F,
+) -> S3Result<(Bytes, String, OffsetDateTime)>
+where
+    F: FnOnce() -> Fut,
+    Fut: Future<Output = S3Result<CapacityFigures>>,
+{
+    let value = caches
+        .current
+        .try_get_with_by_ref(key, async {
+            let _permit = caches.refresh_permits.acquire().await.map_err(|_| capacity_unavailable())?;
+            let bytes = Bytes::from(capacity_xml(&load().await?));
+            let etag_hex = md5_hex(&bytes);
+            let modified_at = caches
+                .history
+                .get(key)
+                .filter(|entry| entry.bytes == bytes)
+                .map_or_else(OffsetDateTime::now_utc, |entry| entry.modified_at);
+            let value = CachedXml {
+                bytes,
+                etag_hex,
+                modified_at,
+            };
+            caches.history.insert(key.clone(), value.clone());
+            Ok::<_, S3Error>(value)
+        })
+        .await
+        .map_err(|_| capacity_unavailable())?;
+    Ok((value.bytes, value.etag_hex, value.modified_at))
+}
+
+fn capacity_unavailable() -> S3Error {
+    S3Error::with_message(S3ErrorCode::ServiceUnavailable, "Veeam SOSAPI capacity is temporarily unavailable")
+}
+
+async fn load_capacity_inputs(store: &Arc<ECStore>, bucket: &str, incarnation: Uuid) -> S3Result<CapacityInputs> {
+    let (quota, quota_incarnation, _) = store.bucket_quota_and_incarnation_from_disk(bucket).await.map_err(|_| {
+        log_quota_unavailable_once(bucket);
+        capacity_unavailable()
+    })?;
+    if quota_incarnation != incarnation {
+        return Err(capacity_unavailable());
+    }
+    let used_bucket = load_bucket_usage_from_backend_cached(Arc::clone(store), bucket, incarnation)
+        .await
+        .ok()
+        .flatten()
+        .ok_or_else(|| {
+            log_usage_missing_once(bucket);
+            capacity_unavailable()
+        })?;
+    let (capacity_cluster, free_cluster) = cached_cluster_capacity(store).await?;
+    Ok(CapacityInputs {
+        used_bucket,
+        hard_quota: quota.as_ref().and_then(hard_quota_bytes),
+        capacity_cluster,
+        free_cluster,
+    })
+}
+
+fn hard_quota_bytes(quota: &BucketQuota) -> Option<u64> {
+    match quota.quota_type {
+        QuotaType::Hard => quota.quota.filter(|size| *size > 0),
+    }
+}
+
+struct ClusterCapacityCache {
+    current: AsyncCache<Uuid, (u64, u64)>,
+    refresh_permits: tokio::sync::Semaphore,
+}
+
+impl ClusterCapacityCache {
+    fn new() -> Self {
+        Self {
+            current: AsyncCache::builder()
+                .max_capacity(CLUSTER_CACHE_ENTRIES)
+                .time_to_live(CAPACITY_XML_CACHE_TTL)
+                .build(),
+            refresh_permits: tokio::sync::Semaphore::new(MAX_CLUSTER_REFRESHES),
+        }
+    }
+}
+
+fn cluster_capacity_cache() -> &'static ClusterCapacityCache {
+    static CACHE: OnceLock<ClusterCapacityCache> = OnceLock::new();
+    CACHE.get_or_init(ClusterCapacityCache::new)
+}
+
+async fn cached_cluster_capacity(store: &Arc<ECStore>) -> S3Result<(u64, u64)> {
+    cached_cluster_capacity_with(cluster_capacity_cache(), store.id, || async {
+        let info = StorageAdminApi::storage_info(store.as_ref()).await;
+        if !cluster_capacity_observations_are_live(&info) {
+            return Err(capacity_unavailable());
+        }
+        conservative_cluster_capacity(&info).ok_or_else(capacity_unavailable)
+    })
+    .await
+}
+
+fn cluster_capacity_observations_are_live(info: &rustfs_madmin::StorageInfo) -> bool {
+    !info.disks.is_empty()
+        && !info.observations.is_empty()
+        && info
+            .observations
+            .iter()
+            .all(|observation| !observation.cached && observation.status == rustfs_madmin::StorageInfoProbeStatus::Succeeded)
+        && info.disks.iter().all(|disk| {
+            (disk.state.eq_ignore_ascii_case("ok") || disk.state.eq_ignore_ascii_case("online"))
+                && disk.capacity_observation_source.as_deref() == Some("live_probe")
+        })
+}
+
+async fn cached_cluster_capacity_with<F, Fut>(cache: &ClusterCapacityCache, store_id: Uuid, load: F) -> S3Result<(u64, u64)>
+where
+    F: FnOnce() -> Fut,
+    Fut: Future<Output = S3Result<(u64, u64)>>,
+{
+    cache
+        .current
+        .try_get_with(store_id, async {
+            let _permit = cache.refresh_permits.acquire().await.map_err(|_| capacity_unavailable())?;
+            load().await
+        })
+        .await
+        .map_err(|_| capacity_unavailable())
+}
+
+/// A set can consume only the space available on each of its shard disks.
+/// This remains an estimate when multiple shard paths share a backing device.
+fn conservative_cluster_capacity(info: &rustfs_madmin::StorageInfo) -> Option<(u64, u64)> {
+    let backend = &info.backend;
+    let pools = backend.drives_per_set.len();
+    if pools == 0
+        || backend.total_sets.len() != pools
+        || backend.standard_sc_data.len() != pools
+        || backend.standard_sc_parities.len() != pools
+    {
+        return None;
+    }
+    let expected = backend
+        .drives_per_set
+        .iter()
+        .zip(&backend.total_sets)
+        .try_fold(0usize, |sum, (&width, &sets)| sum.checked_add(width.checked_mul(sets)?))?;
+    if expected != info.disks.len() {
+        return None;
+    }
+    let mut seen = HashSet::with_capacity(expected);
+    let mut sets: HashMap<(usize, usize), (u64, u64, usize)> = HashMap::new();
+    for disk in &info.disks {
+        let pool = usize::try_from(disk.pool_index).ok()?;
+        let set = usize::try_from(disk.set_index).ok()?;
+        let index = usize::try_from(disk.disk_index).ok()?;
+        let width = *backend.drives_per_set.get(pool)?;
+        if width == 0 || set >= *backend.total_sets.get(pool)? || index >= width || !seen.insert((pool, set, index)) {
+            return None;
+        }
+        let entry = sets.entry((pool, set)).or_insert((u64::MAX, u64::MAX, 0));
+        entry.0 = entry.0.min(disk.total_space);
+        entry.1 = entry.1.min(disk.available_space);
+        entry.2 = entry.2.checked_add(1)?;
+    }
+    let mut total = 0u64;
+    let mut free = 0u64;
+    for ((pool, _), (min_total, min_free, count)) in sets {
+        let width = backend.drives_per_set[pool];
+        let data = backend.standard_sc_data[pool];
+        if count != width
+            || data == 0
+            || data.checked_add(backend.standard_sc_parities[pool]) != Some(width)
+            || min_total == 0
+            || min_free > min_total
+        {
+            return None;
+        }
+        let data = u64::try_from(data).ok()?;
+        total = total.checked_add(min_total.checked_mul(data)?)?;
+        free = free.checked_add(min_free.checked_mul(data)?)?;
+    }
+    Some((total, free))
+}
+
+fn log_usage_missing_once(bucket: &str) {
+    if LOGGED_USAGE_MISSING
+        .compare_exchange(false, true, Ordering::Relaxed, Ordering::Relaxed)
+        .is_ok()
+    {
+        debug!(
+            event = EVENT_USAGE_MISSING,
+            component = LOG_COMPONENT_APP,
+            subsystem = LOG_SUBSYSTEM_OBJECT,
+            state = "snapshot_missing",
+            bucket = %bucket,
+            "Veeam SOSAPI capacity is unavailable because the data-usage snapshot is missing"
+        );
+    }
+}
+
+fn log_quota_unavailable_once(bucket: &str) {
+    if LOGGED_QUOTA_UNAVAILABLE
+        .compare_exchange(false, true, Ordering::Relaxed, Ordering::Relaxed)
+        .is_ok()
+    {
+        debug!(
+            event = EVENT_QUOTA_UNAVAILABLE,
+            component = LOG_COMPONENT_APP,
+            subsystem = LOG_SUBSYSTEM_OBJECT,
+            state = "quota_unavailable",
+            bucket = %bucket,
+            "Veeam SOSAPI capacity is unavailable because the bucket quota could not be read"
+        );
+    }
+}
+
+#[cfg(test)]
+mod tests;

rustfs/src/app/storage_api.rs

@@ -107,6 +107,14 @@ pub(crate) mod data_usage {
         crate::storage::storage_api::ecstore_data_usage::load_admin_data_usage_from_backend_cached(store).await
     }
 
+    pub(crate) async fn load_bucket_usage_from_backend_cached(
+        store: Arc<crate::storage::storage_api::ECStore>,
+        bucket: &str,
+        incarnation: uuid::Uuid,
+    ) -> Result<Option<u64>, crate::storage::storage_api::StorageError> {
+        crate::storage::storage_api::ecstore_data_usage::load_bucket_usage_from_backend_cached(store, bucket, incarnation).await
+    }
+
     #[cfg(test)]
     pub(crate) async fn load_data_usage_from_backend_cached(
         store: Arc<crate::storage::storage_api::ECStore>,
@@ -679,8 +687,8 @@ pub(crate) mod bucket {
             pub(crate) type QuotaChecker = crate::storage::storage_api::ecstore_bucket::quota::checker::QuotaChecker;
         }
 
-        #[cfg(test)]
         pub(crate) type BucketQuota = crate::storage::storage_api::ecstore_bucket::quota::BucketQuota;
+        pub(crate) type QuotaType = crate::storage::storage_api::ecstore_bucket::quota::QuotaType;
         pub(crate) type QuotaOperation = crate::storage::storage_api::ecstore_bucket::quota::QuotaOperation;
         pub(crate) type QuotaCheckResult = crate::storage::storage_api::ecstore_bucket::quota::QuotaCheckResult;
         pub(crate) type QuotaError = crate::storage::storage_api::ecstore_bucket::quota::QuotaError;
@@ -1203,7 +1211,6 @@ pub(crate) mod bucket_usecase {
 }
 
 pub(crate) mod object_usecase {
-    pub(crate) use super::storage_contracts::BUCKET_LIFECYCLE_LOCK_OBJECT;
     pub(crate) use super::storage_contracts::object::DeleteObjectCondition;
     pub(crate) use crate::storage::storage_api::ecstore_object::{WriteCommitGuard, WriteCompletion};
 

rustfs/src/config/info.rs

@@ -528,6 +528,7 @@ struct ConfigInfoJson {
     kms_backend: String,
     buffer_profile: String,
     workload_profile: Option<WorkloadProfileJson>,
+    veeam_sosapi_enable: bool,
 }
 
 /// Workload profile information for JSON output
@@ -572,6 +573,10 @@ fn collect_config_info_json() -> ConfigInfoJson {
         kms_backend: snapshot.kms_backend.clone(),
         buffer_profile: snapshot.buffer_profile.clone(),
         workload_profile,
+        veeam_sosapi_enable: rustfs_utils::get_env_bool(
+            rustfs_config::ENV_VEEAM_SOSAPI_ENABLE,
+            rustfs_config::DEFAULT_VEEAM_SOSAPI_ENABLE,
+        ),
     }
 }
 
@@ -889,6 +894,8 @@ fn format_protocol_config_info() -> String {
         rustfs_utils::get_env_u64(rustfs_config::ENV_WEBDAV_REQUEST_TIMEOUT, DEFAULT_WEBDAV_REQUEST_TIMEOUT_SECS);
     let webdav_max_connections =
         rustfs_utils::get_env_usize(rustfs_config::ENV_WEBDAV_MAX_CONNECTIONS, DEFAULT_WEBDAV_MAX_CONNECTIONS);
+    let veeam_sosapi_enable =
+        rustfs_utils::get_env_bool(rustfs_config::ENV_VEEAM_SOSAPI_ENABLE, rustfs_config::DEFAULT_VEEAM_SOSAPI_ENABLE);
 
     format!(
         "| FTPS | --- |\n\
@@ -909,7 +916,9 @@ fn format_protocol_config_info() -> String {
          | WebDAV > CA File (`{}`) | {} |\n\
          | WebDAV > Max Body Size (`{}`) | {} bytes |\n\
          | WebDAV > Request Timeout (`{}`) | {} seconds |\n\
-         | WebDAV > Max Connections (`{}`) | {} |",
+         | WebDAV > Max Connections (`{}`) | {} |\n\
+         | Veeam SOSAPI | --- |\n\
+         | Veeam SOSAPI > Enabled (`{}`) | {} |",
         if cfg!(feature = "ftps") { "enabled" } else { "disabled" },
         rustfs_config::ENV_FTPS_ENABLE,
         ftps_enable,
@@ -941,7 +950,9 @@ fn format_protocol_config_info() -> String {
         rustfs_config::ENV_WEBDAV_REQUEST_TIMEOUT,
         webdav_request_timeout,
         rustfs_config::ENV_WEBDAV_MAX_CONNECTIONS,
-        webdav_max_connections
+        webdav_max_connections,
+        rustfs_config::ENV_VEEAM_SOSAPI_ENABLE,
+        veeam_sosapi_enable
     )
 }
 
@@ -1137,5 +1148,6 @@ mod tests {
         assert!(output.contains("| WebDAV > Enabled (`RUSTFS_WEBDAV_ENABLE`) |"));
         assert!(output.contains("| WebDAV > Address (`RUSTFS_WEBDAV_ADDRESS`) |"));
         assert!(output.contains("| WebDAV > Max Body Size (`RUSTFS_WEBDAV_MAX_BODY_SIZE`) |"));
+        assert!(output.contains("| Veeam SOSAPI > Enabled (`RUSTFS_VEEAM_SOSAPI_ENABLE`) |"));
     }
 }

rustfs/src/startup_background.rs

@@ -81,6 +81,14 @@ pub(crate) async fn init_background_service_runtime(store: Arc<ECStore>) -> Resu
         let admission = None;
         let heal_storage = Arc::new(ECStoreHealStorage::new(store.clone()).with_admission(admission.clone()));
         init_heal_manager_with_workload_provider(heal_storage, None, Some(workload_provider.clone())).await?;
+        if let Some(admission) = &admission
+            && !rustfs_scanner::set_scanner_node_admission(admission.clone())
+        {
+            return Err(std::io::Error::new(
+                std::io::ErrorKind::AlreadyExists,
+                "scanner node admission is already initialized",
+            ));
+        }
         #[cfg(any(target_os = "linux", all(test, unix)))]
         if let Some(admission) = admission {
             crate::background_admission::start(admission, background_cancel.clone(), workload_provider);