The kubelet taps every pod with three probes. Break a pod with the buttons below and watch what each probe does about it, or press ▶ Guided tour.
| Pod | State | Startup | Liveness | Readiness | Restarts |
|---|---|---|---|---|---|
| web-1 | Ready | passed | 0/3 | 0/3 | 0 |
| web-2 | Ready | passed | 0/3 | 0/3 | 0 |
| web-3 | Ready | passed | 0/3 | 0/3 | 0 |
The kubelet runs each probe once per period. A failing readiness probe only takes the pod out of the Service; it keeps running and comes back when the probe passes. A failing liveness probe means the container is stuck, so after three failures the kubelet restarts it. Without a startup probe, liveness can kill a slow starter before it is up, again and again (CrashLoopBackOff); with one, liveness and readiness wait until the app answers.