# Configuration Reference

> Last reviewed: 2026-05-05

Compact reference for `CERTCTL_*` environment variables consumed by
`certctl-server` and `certctl-agent`. Most operators don't need to
touch these — defaults are tuned for the common case. Reach for them
when the system's behaviour needs tuning beyond what's exposed in the
GUI / API.

This page enumerates the operator-tunable knobs that don't have a
dedicated home elsewhere. Connector-specific env vars are documented
on the per-connector pages under
[`docs/reference/connectors/`](connectors/index.md). Protocol env
vars (ACME server, EST, SCEP) are documented under
[`docs/reference/protocols/`](protocols/). TLS env vars are
documented in [`docs/operator/tls.md`](../operator/tls.md).

## Scheduler intervals

The scheduler runs N background loops; intervals are tunable for
performance / contention tuning.

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_SCHEDULER_AGENT_HEALTH_CHECK_INTERVAL` | `2m` | How often the agent-health loop scans for stale heartbeats and transitions agents to `Unhealthy` / `Offline`. |
| `CERTCTL_SCHEDULER_JOB_PROCESSOR_INTERVAL` | `30s` | How often the job-processor loop dispatches `Pending` jobs to agents. |
| `CERTCTL_SCHEDULER_NOTIFICATION_PROCESS_INTERVAL` | `1m` | How often the notification-dispatcher loop fans out queued alerts to channels. |
| `CERTCTL_SHORT_LIVED_EXPIRY_CHECK_INTERVAL` | `5m` | How often the short-lived-expiry loop watches certs whose TTL is less than 1h for imminent expiry. |

For the full scheduler topology (14 loops, 9 always-on + 5 opt-in)
see [`architecture.md`](architecture.md) "Scheduler topology".

## Job lifecycle

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_JOB_AWAITING_CSR_TIMEOUT` | `24h` | How long a job stays in `AwaitingCSR` before the scheduler marks it `Failed` (the agent never picked it up). |

## Rate limiting

The control plane API is rate-limited by default; tune for
high-volume environments (mass-rotation events, bulk imports).

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_RATE_LIMIT_ENABLED` | `true` | Master toggle. Disable only for trusted-network single-tenant deploys where the API is firewall-protected. |
| `CERTCTL_RATE_LIMIT_PER_USER_RPS` | `0` (= use global default) | Per-user requests-per-second cap. Zero opts each user into the global default in `internal/api/middleware`. |
| `CERTCTL_RATE_LIMIT_PER_USER_BURST` | `0` (= use global default) | Per-user token-bucket burst size. Same opt-in semantics. |

## Audit trail

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_AUDIT_FLUSH_TIMEOUT_SECONDS` | `30` | How long the audit-event flush worker waits for the buffered batch to drain before forcing a flush at shutdown. |

## Deploy verification

The deploy-hardening primitive wraps every cert deploy in
atomic-write + post-verify + rollback. These env vars tune the
post-deploy TLS verification phase.

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_VERIFY_DEPLOYMENT` | `true` | Master toggle for post-deploy TLS verify. Disable only for connectors / environments where the verify endpoint is not reachable from the agent. |
| `CERTCTL_VERIFY_DELAY` | `2s` | How long to wait after the reload command completes before the first verify-handshake attempt (gives the daemon time to pick up new keys). |
| `CERTCTL_VERIFY_TIMEOUT` | `10s` | Per-attempt TLS-handshake timeout. |
| `CERTCTL_DEPLOY_BACKUP_RETENTION` | `3` | How many `.certctl-bak.<unix-nanos>.<ext>` rollback snapshots to keep per target after a successful deploy. `0` uses the default of 3; `-1` opts out of pruning entirely. |

For the full deploy contract see
[`deployment-model.md`](deployment-model.md).

## Database

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_DATABASE_MIGRATIONS_PATH` | `./migrations` | Filesystem path to the `*.up.sql` / `*.down.sql` migration set. Override only when running `certctl-server` from a non-standard layout. |

## Agent

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_AGENT_ID` | (none — required) | The agent's unique ID, issued by `POST /api/v1/agents/register` and bundled into the agent's registration response. Pass via this env var when the agent runs as a systemd unit / container without the `-agent-id` CLI flag. |

## Auth (Bundle 1 + Bundle 2)

Configuration knobs for the RBAC + OIDC + sessions + break-glass
auth surface. Full operator guidance lives in
[`operator/rbac.md`](../operator/rbac.md),
[`operator/oidc-runbooks/`](../operator/oidc-runbooks/index.md), and
[`operator/auth-threat-model.md`](../operator/auth-threat-model.md).

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_SESSION_BIND_USER_AGENT` | `false` | Bind every session cookie to the User-Agent header captured at login; mismatch -> 401. Defense in depth against stolen cookies on the same network. |
| `CERTCTL_SESSION_GC_INTERVAL` | `1h` | How often the scheduler's session-GC loop sweeps expired/revoked rows out of `sessions`. Trade-off: shorter = smaller table, more DB churn; longer = pile-up. |
| `CERTCTL_OIDC_BCL_MAX_AGE_SECONDS` | `60` | Back-channel logout `iat` freshness window. Tokens older or newer than this skew (in either direction) are rejected. |
| `CERTCTL_OIDC_PRELOGIN_REQUIRE_UA` | `false` | Reject the OIDC callback if the User-Agent at callback differs from the UA captured at pre-login. RFC 9700 §4.7.1 defense-in-depth. |
| `CERTCTL_OIDC_PRELOGIN_REQUIRE_IP` | `false` | Same as `_UA` but for client IP. Set carefully — corporate networks with carrier-grade NAT can change apparent IP mid-flow. |
| `CERTCTL_DEMO_MODE_ACK` | `false` | Operator acknowledgement that demo mode is intentional in this deploy. Required when `CERTCTL_AUTH_TYPE=none` to allow server startup; safety net against demo-mode-in-production leakage. |
| `CERTCTL_TRUSTED_PROXIES` | (empty) | Comma-separated list of trusted-proxy CIDRs (e.g. `10.0.0.0/8,192.0.2.1`). XFF is consulted for client-IP derivation only when the immediate peer sits in this allowlist. |
| `CERTCTL_TRUSTED_PROXIES_COUNT` | (synthesised) | Read-only counter exposed by `/api/v1/auth/runtime-config`; mirrors `len(CERTCTL_TRUSTED_PROXIES)`. Not operator-settable; documented here so the G-3 env-docs-drift guard catches drift. |
| `CERTCTL_BOOTSTRAP_TOKEN` | (empty) | One-shot token used to mint the first admin role binding via `POST /api/v1/auth/bootstrap`. Once consumed, deletes itself from memory and unsets the bootstrap endpoint. |
| `CERTCTL_BOOTSTRAP_TOKEN_SET` | (synthesised) | Boolean exposed by `/api/v1/auth/runtime-config`; `true` when `CERTCTL_BOOTSTRAP_TOKEN` was set at server start. Not operator-settable; documented here so the G-3 guard catches drift. |
| `CERTCTL_BOOTSTRAP_OIDC_PROVIDER_ID` | (empty) | When OIDC is enabled, restricts the first-admin OIDC strategy to the named provider only — any other provider's tokens won't trigger the bootstrap hook. |
| `CERTCTL_BOOTSTRAP_ADMIN_GROUPS_COUNT` | (synthesised) | Read-only counter exposed by `/api/v1/auth/runtime-config`; mirrors `len(CERTCTL_BOOTSTRAP_ADMIN_GROUPS)`. Documented here so the G-3 guard catches drift. |
| `CERTCTL_BREAKGLASS_LOCKOUT_THRESHOLD` | `5` | Number of consecutive failed `/auth/breakglass/login` attempts that lock the credential. |

## SCEP profile binding (single-profile back-compat)

| Variable | Default | Description |
|---|---|---|
| `CERTCTL_SCEP_PROFILE_ID` | (empty) | Optional certificate profile ID for the legacy single-profile SCEP path. The multi-profile path uses `CERTCTL_SCEP_PROFILES=<list>` + `CERTCTL_SCEP_PROFILE_<NAME>_PROFILE_ID` instead — see [`scep-server.md`](protocols/scep-server.md). |

## Related references

- [`architecture.md`](architecture.md) — scheduler topology, system design, security model
- [`deployment-model.md`](deployment-model.md) — atomic write + verify + rollback contract
- [`operator/security.md`](../operator/security.md) — full security posture (auth, rate limits, encryption at rest)
- [`operator/tls.md`](../operator/tls.md) — control-plane TLS env vars
- Per-connector pages under [`reference/connectors/`](connectors/index.md) for connector-specific config
- Per-protocol pages under [`reference/protocols/`](protocols/) for ACME / SCEP / EST / CRL+OCSP / async-CA polling