Health Check

ELI5 — The Vibe Check

A Health Check is an automatic 'are you alive?' ping your infrastructure sends to your app regularly. If the app responds with 'yes I'm fine,' everything's good. If it doesn't respond or says 'something's wrong,' the system stops sending traffic to it and tries to restart it. Like checking someone's pulse.

Real Talk

A health check is a periodic automated probe that verifies a service is running correctly. HTTP health checks typically hit an endpoint like /health and expect a 200 response. Kubernetes uses liveness probes (is the container alive?) and readiness probes (is it ready to accept traffic?) to manage pod lifecycle.

Show Me The Code

# Kubernetes health probes
livenessProbe:
  httpGet:
    path: /health
    port: 3000
  initialDelaySeconds: 5
  periodSeconds: 10

readinessProbe:
  httpGet:
    path: /ready
    port: 3000

When You'll Hear This

"The health check is failing — the database connection is down." / "Add a /health endpoint that checks the database before the load balancer routes traffic."