How do you debug a pod stuck in CrashLoopBackOff?

CrashLoopBackOff means the container starts but repeatedly crashes. Use this systematic approach:

1. Check logs: kubectl logs <pod> --previous to see the crash output.
2. Describe the pod: kubectl describe pod <pod> to inspect Events, resource limits, and probe failures.
3. Check OOM: If you see OOMKilled, the container exceeded its memory limit.
4. Shell override: Override the entrypoint to keep the container alive for inspection: command: ["sleep", "3600"]