K8s CrashLoopBackOff

A pod status indicating the application inside the container is repeatedly crashing. Kubernetes restarts it, but it fails again, entering a backoff loop.

Common Causes

Application crashes due to bugs, missing dependencies, or incorrect startup commands.
Misconfigured liveness or readiness probes causing the container to be killed.
Insufficient resources (CPU/Memory) or hitting resource limits (OOMKilled).

How to Fix

1 Check Pod Logs for Application Errors

Examine the logs of the crashing container to identify the root cause of the application failure.

BASH

$ kubectl logs <pod-name> --previous

2 Describe the Pod for Events

Use `kubectl describe` to see recent events, state changes, and potential system-level issues like image pull errors or resource constraints.

BASH

$ kubectl describe pod <pod-name>

3 Debug with an Interactive Shell

If the image supports it, run a temporary debug pod to inspect the filesystem and environment manually.

BASH

$ kubectl run -i --tty debug --image=<your-image> --restart=Never -- sh