diff --git a/crates/ecstore/src/rpc/client.rs b/crates/ecstore/src/rpc/client.rs
index 16f4999bb..521a784a6 100644
--- a/crates/ecstore/src/rpc/client.rs
+++ b/crates/ecstore/src/rpc/client.rs
@@ -143,7 +143,7 @@ mod tests {
     use tracing_subscriber::{Registry, layer::SubscriberExt};
 
     fn ensure_test_rpc_secret() {
-        let _ = rustfs_credentials::GLOBAL_RUSTFS_RPC_SECRET.set("test-rpc-secret".to_string());
+        runtime_sources::ensure_test_rpc_secret();
     }
 
     fn with_trace_parent<F>(trace_id_hex: &str, f: F)
diff --git a/crates/ecstore/src/rpc/http_auth.rs b/crates/ecstore/src/rpc/http_auth.rs
index a62bf029c..9beb270eb 100644
--- a/crates/ecstore/src/rpc/http_auth.rs
+++ b/crates/ecstore/src/rpc/http_auth.rs
@@ -164,6 +164,7 @@ pub fn verify_rpc_signature(url: &str, method: &Method, headers: &HeaderMap) ->
 mod tests {
     use super::*;
     use crate::rpc::context_propagation::REQUEST_ID_HEADER;
+    use crate::runtime_sources;
     use http::{HeaderMap, Method};
     use std::io::{self, Write};
     use std::sync::{Arc, Mutex};
@@ -215,7 +216,7 @@ mod tests {
     }
 
     fn ensure_test_rpc_secret() {
-        let _ = rustfs_credentials::GLOBAL_RUSTFS_RPC_SECRET.set("test-rpc-secret".to_string());
+        runtime_sources::ensure_test_rpc_secret();
     }
 
     #[test]
diff --git a/crates/ecstore/src/rpc/remote_disk.rs b/crates/ecstore/src/rpc/remote_disk.rs
index ee3675bfc..6a9a38020 100644
--- a/crates/ecstore/src/rpc/remote_disk.rs
+++ b/crates/ecstore/src/rpc/remote_disk.rs
@@ -2220,7 +2220,7 @@ impl DiskAPI for RemoteDisk {
 mod tests {
     use super::*;
     use crate::rpc::internode_data_transport::{InternodeDataTransportCapabilities, TcpHttpInternodeDataTransport};
-    use rustfs_common::GLOBAL_CONN_MAP;
+    use crate::runtime_sources;
     use serde_json::Value;
     use std::io::{self as std_io, Write};
     use std::pin::Pin;
@@ -2709,7 +2709,7 @@ mod tests {
     #[tokio::test]
     async fn test_remote_disk_recovery_requires_disk_rpc_readiness() {
         init_tracing(Level::ERROR);
-        let _ = rustfs_credentials::GLOBAL_RUSTFS_RPC_SECRET.set("test-rpc-secret".to_string());
+        runtime_sources::ensure_test_rpc_secret();
 
         let listener = match TcpListener::bind("127.0.0.1:0").await {
             Ok(listener) => listener,
@@ -2737,8 +2737,8 @@ mod tests {
         health.mark_failure(&endpoint, "test_failure");
         assert_eq!(health.runtime_state(), RuntimeDriveHealthState::Offline);
         let channel = TonicEndpoint::from_shared(base_addr.clone()).unwrap().connect_lazy();
-        GLOBAL_CONN_MAP.write().await.insert(base_addr.clone(), channel);
-        assert!(GLOBAL_CONN_MAP.read().await.contains_key(&base_addr));
+        runtime_sources::cache_test_node_channel(base_addr.clone(), channel).await;
+        assert!(runtime_sources::test_node_channel_is_cached(&base_addr).await);
 
         temp_env::async_with_vars(
             [
@@ -2764,7 +2764,7 @@ mod tests {
                     "a plain TCP listener without disk_info RPC readiness must not restore the remote disk online"
                 );
                 assert!(
-                    !GLOBAL_CONN_MAP.read().await.contains_key(&base_addr),
+                    !runtime_sources::test_node_channel_is_cached(&base_addr).await,
                     "failed recovery probes should evict stale cached gRPC channels"
                 );
             },
@@ -3336,8 +3336,8 @@ mod tests {
         .unwrap();
 
         let channel = TonicEndpoint::from_shared(addr.clone()).unwrap().connect_lazy();
-        GLOBAL_CONN_MAP.write().await.insert(addr.clone(), channel);
-        assert!(GLOBAL_CONN_MAP.read().await.contains_key(&addr));
+        runtime_sources::cache_test_node_channel(addr.clone(), channel).await;
+        assert!(runtime_sources::test_node_channel_is_cached(&addr).await);
 
         let _ = remote_disk
             .execute_with_timeout(
@@ -3351,7 +3351,7 @@ mod tests {
             .expect_err("timeout should fail");
 
         assert!(
-            !GLOBAL_CONN_MAP.read().await.contains_key(&addr),
+            !runtime_sources::test_node_channel_is_cached(&addr).await,
             "timeout should evict cached connection"
         );
     }
@@ -3380,7 +3380,7 @@ mod tests {
         .unwrap();
 
         let channel = TonicEndpoint::from_shared(addr.clone()).unwrap().connect_lazy();
-        GLOBAL_CONN_MAP.write().await.insert(addr.clone(), channel);
+        runtime_sources::cache_test_node_channel(addr.clone(), channel).await;
 
         let err = remote_disk
             .execute_with_timeout(
@@ -3407,7 +3407,7 @@ mod tests {
             "first timeout-like error should move the remote disk into suspect state"
         );
         assert!(
-            !GLOBAL_CONN_MAP.read().await.contains_key(&addr),
+            !runtime_sources::test_node_channel_is_cached(&addr).await,
             "timeout-like errors should evict cached connection"
         );
     }
@@ -3436,7 +3436,7 @@ mod tests {
         .unwrap();
 
         let channel = TonicEndpoint::from_shared(addr.clone()).unwrap().connect_lazy();
-        GLOBAL_CONN_MAP.write().await.insert(addr.clone(), channel);
+        runtime_sources::cache_test_node_channel(addr.clone(), channel).await;
 
         let err = remote_disk
             .execute_with_timeout(
@@ -3468,7 +3468,7 @@ mod tests {
             "first network-like error should move the remote disk into suspect state"
         );
         assert!(
-            !GLOBAL_CONN_MAP.read().await.contains_key(&addr),
+            !runtime_sources::test_node_channel_is_cached(&addr).await,
             "network-like errors should evict cached connection"
         );
     }
@@ -3497,7 +3497,7 @@ mod tests {
         .unwrap();
 
         let channel = TonicEndpoint::from_shared(addr.clone()).unwrap().connect_lazy();
-        GLOBAL_CONN_MAP.write().await.insert(addr.clone(), channel);
+        runtime_sources::cache_test_node_channel(addr.clone(), channel).await;
 
         let err = remote_disk
             .execute_with_timeout_for_op_and_health_action(
@@ -3521,7 +3521,7 @@ mod tests {
             "ignored network-like error should not mark remote disk faulty"
         );
         assert!(
-            GLOBAL_CONN_MAP.read().await.contains_key(&addr),
+            runtime_sources::test_node_channel_is_cached(&addr).await,
             "ignored network-like error should not evict cached connection"
         );
     }
@@ -3550,7 +3550,7 @@ mod tests {
         .unwrap();
 
         let channel = TonicEndpoint::from_shared(addr.clone()).unwrap().connect_lazy();
-        GLOBAL_CONN_MAP.write().await.insert(addr.clone(), channel);
+        runtime_sources::cache_test_node_channel(addr.clone(), channel).await;
 
         let err = remote_disk
             .execute_with_timeout(|| async { Err::<(), Error>(DiskError::FileNotFound) }, Duration::from_secs(1))
@@ -3560,7 +3560,7 @@ mod tests {
         assert_eq!(err, DiskError::FileNotFound);
         assert!(remote_disk.is_online().await, "business errors should not mark remote disk faulty");
         assert!(
-            GLOBAL_CONN_MAP.read().await.contains_key(&addr),
+            runtime_sources::test_node_channel_is_cached(&addr).await,
             "business errors should not evict cached connection"
         );
     }
diff --git a/crates/ecstore/src/rpc/remote_locker.rs b/crates/ecstore/src/rpc/remote_locker.rs
index dda07e623..2a34922d1 100644
--- a/crates/ecstore/src/rpc/remote_locker.rs
+++ b/crates/ecstore/src/rpc/remote_locker.rs
@@ -536,7 +536,7 @@ impl LockClient for RemoteClient {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use rustfs_common::GLOBAL_CONN_MAP;
+    use crate::runtime_sources;
     use rustfs_lock::{ObjectKey, types::LockPriority};
     use tokio::net::TcpListener;
     use tokio::task::JoinHandle;
@@ -560,11 +560,11 @@ mod tests {
 
     async fn cache_lazy_channel(addr: &str) {
         let channel = TonicEndpoint::from_shared(addr.to_string()).unwrap().connect_lazy();
-        GLOBAL_CONN_MAP.write().await.insert(addr.to_string(), channel);
+        runtime_sources::cache_test_node_channel(addr.to_string(), channel).await;
     }
 
     fn ensure_test_rpc_secret() {
-        let _ = rustfs_credentials::GLOBAL_RUSTFS_RPC_SECRET.set("test-rpc-secret".to_string());
+        runtime_sources::ensure_test_rpc_secret();
     }
 
     fn test_lock_request(timeout_duration: Duration) -> LockRequest {
@@ -581,7 +581,7 @@ mod tests {
             return;
         };
         cache_lazy_channel(&addr).await;
-        assert!(GLOBAL_CONN_MAP.read().await.contains_key(&addr));
+        assert!(runtime_sources::test_node_channel_is_cached(&addr).await);
 
         temp_env::async_with_vars([(rustfs_config::ENV_OBJECT_LOCK_RPC_TIMEOUT_MS, Some("50"))], async {
             let client = RemoteClient::new(addr.clone());
@@ -609,7 +609,7 @@ mod tests {
                 response.error
             );
             assert!(
-                !GLOBAL_CONN_MAP.read().await.contains_key(&addr),
+                !runtime_sources::test_node_channel_is_cached(&addr).await,
                 "transport timeout should evict cached connection"
             );
         })
@@ -626,7 +626,7 @@ mod tests {
             return;
         };
         cache_lazy_channel(&addr).await;
-        assert!(GLOBAL_CONN_MAP.read().await.contains_key(&addr));
+        assert!(runtime_sources::test_node_channel_is_cached(&addr).await);
 
         temp_env::async_with_vars([(rustfs_config::ENV_OBJECT_LOCK_RPC_TIMEOUT_MS, Some("50"))], async {
             let client = RemoteClient::new(addr.clone());
@@ -655,7 +655,7 @@ mod tests {
                 responses[0].error
             );
             assert!(
-                !GLOBAL_CONN_MAP.read().await.contains_key(&addr),
+                !runtime_sources::test_node_channel_is_cached(&addr).await,
                 "batch transport timeout should evict cached connection"
             );
         })
diff --git a/crates/ecstore/src/runtime_sources.rs b/crates/ecstore/src/runtime_sources.rs
index a76e87544..3d7c76b19 100644
--- a/crates/ecstore/src/runtime_sources.rs
+++ b/crates/ecstore/src/runtime_sources.rs
@@ -50,6 +50,9 @@ use tokio::sync::RwLock;
 use tonic::transport::Channel;
 use uuid::Uuid;
 
+#[cfg(test)]
+const TEST_RPC_SECRET: &str = "test-rpc-secret";
+
 pub(crate) fn record_erasure_write_quorum_failure(stage: &'static str, dominant_error: &'static str) {
     global_internode_metrics().record_erasure_write_quorum_failure(stage, dominant_error);
 }
@@ -165,6 +168,21 @@ pub(crate) async fn cached_node_channel(addr: &str) -> Option<Channel> {
     GLOBAL_CONN_MAP.read().await.get(addr).cloned()
 }
 
+#[cfg(test)]
+pub(crate) async fn cache_test_node_channel(addr: String, channel: Channel) {
+    GLOBAL_CONN_MAP.write().await.insert(addr, channel);
+}
+
+#[cfg(test)]
+pub(crate) async fn test_node_channel_is_cached(addr: &str) -> bool {
+    GLOBAL_CONN_MAP.read().await.contains_key(addr)
+}
+
+#[cfg(test)]
+pub(crate) fn ensure_test_rpc_secret() {
+    let _ = rustfs_credentials::GLOBAL_RUSTFS_RPC_SECRET.set(TEST_RPC_SECRET.to_owned());
+}
+
 pub(crate) fn storage_class_parity(storage_class: Option<&str>) -> Option<usize> {
     get_global_storage_class().and_then(|sc| sc.get_parity_for_sc(storage_class.unwrap_or_default()))
 }
diff --git a/docs/architecture/migration-progress.md b/docs/architecture/migration-progress.md
index 562b69622..ca64ec4ef 100644
--- a/docs/architecture/migration-progress.md
+++ b/docs/architecture/migration-progress.md
@@ -5,9 +5,9 @@ Status values: `[ ]` not started, `[~]` in progress, `[x]` complete, `[!]` block
 ## Current Context
 
 - Issue: [`rustfs/backlog#660`](https://github.com/rustfs/backlog/issues/660)
-- Branch: `overtrue/arch-ecstore-batch-config-runtime-sources`
-- Baseline: completed `C-011/C-012/C-013/API-055/API-059/API-079/API-080/API-081/API-082/API-083/API-084/API-085/API-086/API-087/API-088/API-089/API-090/API-091/API-092/API-093/API-094/API-095/API-096/API-097/API-098/API-099/API-100/API-101/API-102/API-103/API-104/API-105/API-106/API-107/API-108/API-109/API-110/API-111/API-112/API-113/API-114/API-115/API-116/API-117/API-118/API-119/API-120/API-121/API-122/API-123/API-124/API-125/API-126/API-127/API-128/API-129/API-130/API-131/API-132/API-133/API-134/API-135/API-136/API-137/API-138/API-139/API-140/API-141/API-142/API-143/API-144/API-145/API-146/API-147/API-148/API-149/API-150/API-151/API-152/API-153/API-154/API-155/API-156/API-157/API-158/API-159/API-160/API-161/API-162/API-163/API-164/API-165/API-166/API-167/API-168/API-169/API-170/API-171/API-172/API-173/API-174/API-175/API-176/API-177/API-178/API-179/API-180/API-181/API-182/API-183/API-184/API-185/API-186/API-187/API-188/API-189/API-190/API-191/API-192/API-193/API-194/API-195/API-196/API-197`.
-- Based on: API-196 merged main.
+- Branch: `overtrue/arch-ecstore-rpc-test-runtime-sources`
+- Baseline: completed `C-011/C-012/C-013/API-055/API-059/API-079/API-080/API-081/API-082/API-083/API-084/API-085/API-086/API-087/API-088/API-089/API-090/API-091/API-092/API-093/API-094/API-095/API-096/API-097/API-098/API-099/API-100/API-101/API-102/API-103/API-104/API-105/API-106/API-107/API-108/API-109/API-110/API-111/API-112/API-113/API-114/API-115/API-116/API-117/API-118/API-119/API-120/API-121/API-122/API-123/API-124/API-125/API-126/API-127/API-128/API-129/API-130/API-131/API-132/API-133/API-134/API-135/API-136/API-137/API-138/API-139/API-140/API-141/API-142/API-143/API-144/API-145/API-146/API-147/API-148/API-149/API-150/API-151/API-152/API-153/API-154/API-155/API-156/API-157/API-158/API-159/API-160/API-161/API-162/API-163/API-164/API-165/API-166/API-167/API-168/API-169/API-170/API-171/API-172/API-173/API-174/API-175/API-176/API-177/API-178/API-179/API-180/API-181/API-182/API-183/API-184/API-185/API-186/API-187/API-188/API-189/API-190/API-191/API-192/API-193/API-194/API-195/API-196/API-197/API-198`.
+- Based on: stacked on API-197 PR branch while PR #3817 is pending.
 - PR type for this branch: `consumer-migration`
 - Runtime behavior changes: none.
 - Rust code changes: route replication pool, outbound TLS generation, runtime
@@ -32,8 +32,9 @@ Status values: `[ ]` not started, `[~]` in progress, `[x]` complete, `[!]` block
   client paths, plus ECStore facade server-config, storage-class,
   notification, bucket-metadata, endpoint, region, tier-config, server-address,
   object-store publication, lock-client publication, and local-node publication
-  paths, plus ECStore batch processor, dynamic storage-class publication, and
-  RustFS cluster snapshot facade alias paths,
+  paths, plus ECStore batch processor, dynamic storage-class publication,
+  RustFS cluster snapshot facade alias paths, and ECStore RPC test runtime
+  global helpers,
   through AppContext-first or owner-crate resolver boundaries.
 - CI/script changes: lock completed owner and test/fuzz boundaries against
   bare/glob imports, scattered raw ECStore facade subpaths, and startup
@@ -43,7 +44,7 @@ Status values: `[ ]` not started, `[~]` in progress, `[x]` complete, `[!]` block
   and storage owner thin bridge regressions, plus app context and notify
   event-bridge thin module regressions; accept the reviewed AppContext resolver
   reverse dependencies in the layer baseline.
-- Docs changes: record the API-136 through API-197 owner facade cleanup.
+- Docs changes: record the API-136 through API-198 owner facade cleanup.
 
 ## Phase 0 Tasks
 
@@ -4880,6 +4881,19 @@ Status values: `[ ]` not started, `[~]` in progress, `[x]` complete, `[!]` block
     formatting, diff hygiene, residual runtime-source scan, migration/layer
     guards, PR-before-push quality gate, and three-expert review.
 
+- [x] `API-198` Centralize ECStore RPC test runtime globals.
+  - Do: route RPC test connection-cache seeding, connection-cache assertions,
+    and test RPC secret initialization through the ECStore runtime-source
+    boundary.
+  - Acceptance: RPC client, HTTP auth, remote locker, and remote disk tests no
+    longer import or mutate `GLOBAL_CONN_MAP` or `GLOBAL_RUSTFS_RPC_SECRET`
+    directly.
+  - Must preserve: cached-channel eviction assertions, timeout behavior,
+    signature generation behavior, and test-only secret initialization.
+  - Verification: focused RPC tests, formatting, diff hygiene, residual runtime
+    global scan, migration/layer guards, fast PR gate, and full PR gate before
+    PR.
+
 ## Next PRs
 
 1. `consumer-migration`: continue reducing direct global reads behind AppContext resolver boundaries.
@@ -4888,6 +4902,9 @@ Status values: `[ ]` not started, `[~]` in progress, `[x]` complete, `[!]` block
 
 | Expert | Status | Notes |
 |---|---|---|
+| Quality/architecture | pass | API-198 keeps RPC test connection-cache and RPC-secret globals behind the ECStore runtime-source test boundary. |
+| Migration preservation | pass | Cached-channel eviction assertions, timeout behavior, signature generation behavior, and test-only secret initialization preserve existing semantics. |
+| Testing/verification | pass | Focused RPC tests, formatting, migration/layer guards, residual scan, fast PR gate, and full PR gate are planned before PR. |
 | Quality/architecture | pass | API-197 keeps set-disk batch processor lookup, dynamic storage-class publication, and RustFS cluster snapshot facade imports behind owner boundaries. |
 | Migration preservation | pass | Batch concurrency defaults, storage-class lookup by drive count, first-set publication, config error handling, and cluster snapshot response shape preserve existing behavior. |
 | Testing/verification | pass | ECStore compile, focused set-disk/config checks, formatting, migration/layer guards, residual scan, fast PR gate, and full PR gate are planned before PR. |