🎓 Mission Debrief: Init Container Gridlock¶

What Happened¶

Your init container was waiting for a service that doesn't exist. Init containers must complete before main containers start, so your pod was stuck in "Init:0/1" status forever.

How Kubernetes Behaved¶

Init containers run before app containers and must complete successfully:

Init containers run sequentially (one after another)
Each must exit with status 0 (success)
Only after ALL init containers complete do app containers start
If init container fails, pod restarts (subject to restartPolicy)

The Correct Mental Model¶

Lifecycle:

Init Container 1 → Init Container 2 → Main Container 1 & Main Container 2
  (sequential)       (sequential)          (parallel)

Common use cases: - Wait for dependencies (databases, services) - Clone git repositories - Generate configuration files - Set up permissions - Database schema migrations

Commands You Mastered¶

# Check init container status
kubectl get pod <name> -n <namespace>
# Look for "Init:0/1" or "Init:Error"

# View init container logs
kubectl logs <pod> -c <init-container-name> -n <namespace>

# See init container details
kubectl describe pod <name> -n <namespace>
# Look at "Init Containers:" section

What's Next¶

Final level: Namespace isolation issues!