Rollback Guidance
Recovery procedures for deployment failures. Referenced from Section 4 (Deploy).
Image Build Failed
# No cloud resources were persisted — nothing to roll back.
# Fix the issue and retry:
# Common fixes:
# - Dockerfile syntax error → edit Dockerfile
# - Missing file in build context → check .dockerignore
# - Dependency install failure → fix package.json / requirements.txt / go.mod
# Retry:
az acr build --registry <acr-name> --image <app-name>:<git-sha> .kubectl apply Failed (Section 4 — Deploy to Cluster)
# Remove the partially applied resources:
kubectl delete -f k8s/
# Common fixes:
# - YAML syntax error → validate with: kubectl apply -f k8s/ --dry-run=client
# - Invalid resource field → check API version matches cluster version
# - Image pull error → verify ACR name in deployment.yaml matches actual ACR
# - Namespace doesn't exist → create it first or remove namespace from manifests
# Fix and retry:
kubectl apply -f k8s/Pods Not Starting (Section 5 — Verify)
# Diagnose:
kubectl get pods -l app=myapp
kubectl describe pod -l app=myapp
kubectl logs -l app=myapp --tail=50
# Common error patterns:
# CrashLoopBackOff — app crashes on startup
# → Check logs for the crash reason
# → Usually: missing env var, bad database connection string, port mismatch
# ImagePullBackOff — can't pull the container image
# → Verify image name: kubectl get deployment myapp -o jsonpath='{.spec.template.spec.containers[0].image}'
# → Verify ACR access: az aks check-acr --resource-group <rg> --name <aks> --acr <acr>.azurecr.io
# Pending — pod can't be scheduled
# → Check node status: kubectl get nodes
# → Check resource requests vs available capacity: kubectl describe nodes
# OOMKilled — app exceeded memory limit
# → Increase memory limit in k8s/deployment.yaml and re-apply
# After fixing, re-apply:
kubectl apply -f k8s/
kubectl rollout status deployment/myapp --timeout=300s