Health check and status page

In short: A health check is an address that reports whether a service is running and can reach its dependencies. A status page shows this to the outside.

In more detail: A simple check answers “200 OK” if the application is alive. A deeper check tests database, cache and external services. Load balancers and Kubernetes use health checks to take sick instances out of service.

In Depth

• Liveness and readiness: “Is the process alive?” and “Can it accept requests?”
• Cron monitoring: Regular tasks report after every run. If the report is missing, an alarm goes off.
• Status page: shows current incidents and history, builds trust.
• External monitoring: Services that query from outside every few minutes also notice outages of an entire data centre.

See also: Observability: logs, metrics and traces, Load balancer