gitlab-org--gitlab-foss/doc/user/admin_area/monitoring/health_check.md

type
concepts, howto

Health Check

• Liveness and readiness probes were introduced in GitLab 9.1.
• The health_check endpoint was introduced in GitLab 8.8 and was be deprecated in GitLab 9.1.
• Access token has been deprecated in GitLab 9.4 in favor of IP whitelist.

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 filesystem. These endpoints can be provided to schedulers like Kubernetes to hold traffic until the system is ready or restart the container as needed.

IP whitelist

To access monitoring resources, the requesting client IP needs to be included in a whitelist. For details, see how to add IPs to a whitelist for the monitoring endpoints.

Using the endpoints

With default whitelist settings, the probes can be accessed from localhost using the following URLs:

• http://localhost/-/health
• http://localhost/-/readiness
• http://localhost/-/liveness

The first endpoint, health, only checks whether the application server is running. It does not verify the database or other services are running. A successful response will return a 200 status code with the following message:

GitLab OK

The readiness and liveness probes will provide a report of system health in JSON format.

readiness probe example output:

{
   "queues_check" : {
      "status" : "ok"
   },
   "redis_check" : {
      "status" : "ok"
   },
   "shared_state_check" : {
      "status" : "ok"
   },
   "db_check" : {
      "status" : "ok"
   },
   "cache_check" : {
      "status" : "ok"
   }
}

liveness probe example output:

{
   "cache_check" : {
      "status" : "ok"
   },
   "db_check" : {
      "status" : "ok"
   },
   "redis_check" : {
      "status" : "ok"
   },
   "queues_check" : {
      "status" : "ok"
   },
   "shared_state_check" : {
      "status" : "ok"
   }
}

Status

On failure, the endpoint will return a 500 HTTP status code. On success, the endpoint will return a valid successful HTTP status code, and a success message.

Access token (Deprecated)

NOTE: Note: Access token has been deprecated in GitLab 9.4 in favor of IP whitelist.

An access token needs to be provided while accessing the probe endpoints. The current accepted token can be found under the Admin area ➔ Monitoring ➔ Health check (admin/health_check) page of your GitLab instance.

The access token can be passed as a URL parameter:

https://gitlab.example.com/-/readiness?token=ACCESS_TOKEN