Skip to content
Canonical source: docs/usage/config-center-runtime-operations.md. This page is rendered from the source document during the MkDocs build.

Config Center Runtime Operations

Bootstrap

Router bootstrap must set NEKIRO_ROUTER_INSTANCE_ROUTING_MODE to exactly direct, config_center_file, or nacos. File mode additionally requires an absolute root, a positive payload limit, a strict configuration key, and an instance port name. The mapped file must contain a valid router-instance-directory.v1 document before the Router starts.

Nacos mode requires one exact API origin ending in /nacos, namespace ID, configuration group, authentication mode, response byte limit, request timeout, strict directory key, and instance port name. Authentication is explicitly none or access_token; the token must be absent in none mode. The configured Nacos key must contain a valid router-nacos-instance-bindings.v1 document before the Router starts. Each exact Release target maps to one Nacos service, group, and cluster. Keys that are already legal Nacos dataIds are passed without translation. A slash-separated key, or a key beginning with the reserved nekiro.key.v1. prefix, maps to nekiro.key.v1. followed by the unpadded Base64URL encoding of the complete key. This mapping is collision-free; the existing router.nacos-bindings dataId remains unchanged.

The scheme in NEKIRO_ROUTER_NACOS_API_ORIGIN explicitly selects the HTTP transport used for both the Config Center binding read and the initial Naming snapshot:

  • http selects controlled plaintext. All NEKIRO_ROUTER_NACOS_HTTP_TLS_* fields must be absent.
  • https requires NEKIRO_ROUTER_NACOS_HTTP_TLS_CA_FILE as a clean absolute private CA bundle path and NEKIRO_ROUTER_NACOS_HTTP_TLS_SERVER_NAME as a canonical lowercase DNS name or canonical IP address.
  • HTTPS uses mTLS when both NEKIRO_ROUTER_NACOS_HTTP_TLS_CLIENT_CERT_FILE and NEKIRO_ROUTER_NACOS_HTTP_TLS_CLIENT_KEY_FILE are present. Supplying only one is invalid.

The HTTP client uses only the configured private CA, keeps hostname verification enabled, and disables environment proxies and redirects. It does not use system roots, downgrade HTTPS, or switch authority. HTTP and gRPC TLS files share the same bootstrap rules: regular and non-empty, at most 1 MiB, strictly valid for their role, and read only when Router starts. Rotation requires a Router restart. Errors do not expose paths, PEM/key bytes, file contents, or parser details.

Nacos Naming observation is optional and disabled by default. Enabling it requires all of NEKIRO_ROUTER_NACOS_GRPC_TARGET, NEKIRO_ROUTER_NACOS_GRPC_CLIENT_IP, NEKIRO_ROUTER_NACOS_GRPC_REQUEST_TIMEOUT_MS, NEKIRO_ROUTER_NACOS_PENDING_CHANGES, NEKIRO_ROUTER_NACOS_MAX_OBSERVATIONS, and the explicit NEKIRO_ROUTER_NACOS_GRPC_TRANSPORT_SECURITY together with NEKIRO_ROUTER_NACOS_OBSERVE_ENABLED=true. Transport security must be exactly one of:

  • insecure: explicit plaintext for local or controlled deployments. All TLS fields must be absent.
  • tls: requires NEKIRO_ROUTER_NACOS_GRPC_TLS_CA_FILE as a clean absolute path and NEKIRO_ROUTER_NACOS_GRPC_TLS_SERVER_NAME as a canonical lowercase DNS name or canonical IP address.
  • mtls: requires the TLS fields plus clean absolute NEKIRO_ROUTER_NACOS_GRPC_TLS_CLIENT_CERT_FILE and NEKIRO_ROUTER_NACOS_GRPC_TLS_CLIENT_KEY_FILE paths.

TLS files must be regular, non-empty, at most 1 MiB, and valid for their role. The CA bundle supplies the complete private trust pool; system roots are not used, hostname verification stays enabled, and client certificate fields are accepted only in mTLS mode. TLS material is read only during Router bootstrap, so rotation requires a Router restart. Partial or mode-incompatible gRPC/TLS configuration is rejected. Errors never include a configured path, PEM data, private-key bytes, or file contents. The executor opens one connection and never falls back to plaintext, retries, reconnects, polls, switches authority, or serves cached topology after failure. The first Invocation for an exact Release atomically establishes its observation and uses the initial snapshot. Later Invocations read the latest immutable watched snapshot without issuing a Naming list request. One observation is retained per exact Release until Router shutdown, bounded by the configured maximum.

Secrets, database URLs, Router signing keys, and service authentication remain bootstrap configuration. They are not accepted in the instance directory.

Rollout

  1. Publish and authorize the exact Agent Release through the Control Plane.
  2. Build a directory target from the published Release ID, Card digest, Agent identity, canonical endpoint, and canonical audience.
  3. In File mode, publish the complete replacement directory document atomically. In Nacos mode, publish the complete binding document after the Agent service has registered its ephemeral instance.
  4. Wait for /readyz to return 200 with {"status":"ok"}.

For an observe-enabled Router, use the configured Router service Bearer credential to read GET /internal/v1/instance-topology/status. The response is safe evidence of topology already consumed by Router; it is not a refresh operation. Record the exact target's localRevision, state, and observedAt before a lifecycle change. After deregistration, wait for the same Agent, version, and Release to report state=empty with a greater local revision before issuing the fail-closed acceptance Invocation. An AGENT_UNAVAILABLE response without that status transition does not prove watch consumption.

The status route is absent in direct and snapshot-only modes. Never treat a 404 there as an empty observed topology. Revisions are local to the current Router observation and cannot be compared across restarts or targets. 5. Invoke through the Control Plane and verify the normal Ledger lineage.

The current selector requires exactly one ready TCP endpoint for the configured port name. Do not publish multiple ready endpoints until a selection policy is approved and deployed.

Rejected Updates

Malformed JSON, duplicate members, unknown fields, unsupported schema versions, invalid Release facts, duplicate Release IDs, invalid addresses, and invalid instance topology make readiness return 503. New Invocations fail closed. Existing streams keep their already selected instance and credential audience.

No last-known-good document is retained. Fix the document at the configured source; do not switch sources or enable direct routing as an incident fallback.

Deletion And Outage

Deleting the configured key, removing the File source root, losing permissions, interrupting the File watcher, or making the configured Nacos origin unavailable makes the directory unavailable. Readiness returns 503, and affected new Invocations fail with dependency semantics. Configuration bytes, paths, source errors, and credentials are never returned by readiness.

Recovery

Restore the same configured source and publish one complete valid document. If the File reader has entered a terminal interrupted state, restart the Router after repairing the source. Nacos observation mode does not recover a terminal watch. Restart the Router after repairing the same configured source to establish fresh observations. It has no stale snapshot fallback, retry, polling, or alternate server. The Router never retries or reroutes an already failed Invocation.