--- stage: Monitor group: Respond info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/product/ux/technical-writing/#assignments --- # Health Check **(FREE SELF)** GitLab provides liveness and readiness probes to indicate service health and reachability to required services. These probes report on the status of the database connection, Redis connection, and access to the file system. These endpoints [can be provided to schedulers like Kubernetes](https://kubernetes.io/docs/tasks/configure-pod-container/configure-liveness-readiness-startup-probes/) to hold traffic until the system is ready or restart the container as needed. ## IP allowlist To access monitoring resources, the requesting client IP needs to be included in the allowlist. For details, see [how to add IPs to the allowlist for the monitoring endpoints](../../../administration/monitoring/ip_allowlist.md). ## Using the endpoints locally With default allowlist settings, the probes can be accessed from localhost using the following URLs: ```plaintext GET http://localhost/-/health ``` ```plaintext GET http://localhost/-/readiness ``` ```plaintext GET http://localhost/-/liveness ``` ## Health Checks whether the application server is running. It does not verify the database or other services are running. This endpoint circumvents Rails Controllers and is implemented as additional middleware `BasicHealthCheck` very early into the request processing lifecycle. ```plaintext GET /-/health ``` Example request: ```shell curl "https://gitlab.example.com/-/health" ``` Example response: ```plaintext GitLab OK ``` ## Readiness The readiness probe checks whether the GitLab instance is ready to accept traffic via Rails Controllers. The check by default does validate only instance-checks. If the `all=1` parameter is specified, the check also validates the dependent services (Database, Redis, Gitaly etc.) and gives a status for each. ```plaintext GET /-/readiness GET /-/readiness?all=1 ``` Example request: ```shell curl "https://gitlab.example.com/-/readiness" ``` Example response: ```json { "master_check":[{ "status":"failed", "message": "unexpected Master check result: false" }], ... } ``` On failure, the endpoint returns a `503` HTTP status code. This check does hit the database and Redis if authenticated via `token`. This check is being exempt from Rack Attack. ## Liveness WARNING: In GitLab [12.4](https://about.gitlab.com/upcoming-releases/) the response body of the Liveness check was changed to match the example below. Checks whether the application server is running. This probe is used to know if Rails Controllers are not deadlocked due to a multi-threading. ```plaintext GET /-/liveness ``` Example request: ```shell curl "https://gitlab.example.com/-/liveness" ``` Example response: On success, the endpoint returns a `200` HTTP status code, and a response like below. ```json { "status": "ok" } ``` On failure, the endpoint returns a `503` HTTP status code. This check is being exempt from Rack Attack. ## Sidekiq Learn how to configure the [Sidekiq health checks](../../../administration/sidekiq/sidekiq_health_check.md).