StatefulSet Force-Delete Corrupts PersistentVolume

# List resources
kubectl get pods
kubectl get pods -o wide          # + node and IP
kubectl get pods --all-namespaces # all namespaces
kubectl get deployments
kubectl get services
kubectl get nodes
kubectl get all                   # pods, services, deployments in current namespace

# Get YAML/JSON of a resource
kubectl get pod myapp-pod -o yaml
kubectl get deployment myapp-deployment -o json

# Detailed view with events — essential for debugging
kubectl describe pod myapp-pod
kubectl describe node my-node

# Watch resources update in real time
kubectl get pods -w

# Custom columns output
kubectl get pods -o custom-columns=NAME:.metadata.name,STATUS:.status.phase

# ── PRODUCTION-GRADE EXTRAS ──────────────────────────────────────────────

# Extract a specific field with jsonpath
kubectl get pod myapp-pod -o jsonpath='{.status.podIP}'
kubectl get pods -o jsonpath='{range .items[*]}{.metadata.name}{"\t"}{.status.podIP}{"\n"}{end}'

# Get all pods with their resource requests
kubectl get pods -o custom-columns=NAME:.metadata.name,CPU_REQ:.spec.containers[0].resources.requests.cpu,MEM_REQ:.spec.containers[0].resources.requests.memory

# Find pods without resource limits (security/compliance check)
kubectl get pods -A -o json | jq -r '.items[] | select(.spec.containers[].resources.limits == null) | .metadata.namespace + "/" + .metadata.name'

# Get events sorted by time — critical for post-incident analysis
kubectl get events --sort-by='.lastTimestamp' -A

# Get events for a specific resource
kubectl get events --field-selector involvedObject.name=myapp-pod

# Check API server health
kubectl get --raw /healthz
kubectl get --raw /readyz
kubectl get --raw /livez

# Container logs
kubectl logs myapp-pod
kubectl logs myapp-pod -c container-name  # specific container
kubectl logs myapp-pod --previous          # logs from crashed container
kubectl logs -f deployment/myapp           # follow deployment logs
kubectl logs myapp-pod --tail=100          # last 100 lines

# Execute commands inside a container
kubectl exec -it myapp-pod -- bash
kubectl exec -it myapp-pod -- sh           # if bash not available
kubectl exec myapp-pod -- env              # print env vars
kubectl exec myapp-pod -- cat /config/app.properties

# Port forward to access a service locally
kubectl port-forward pod/myapp-pod 8080:8000
kubectl port-forward service/myapp-svc 8080:80

# Copy files to/from a pod
kubectl cp myapp-pod:/var/log/app.log ./app.log
kubectl cp ./config.yaml myapp-pod:/app/config.yaml

# ── PRODUCTION-GRADE DEBUGGING ───────────────────────────────────────────

# Logs from all pods in a deployment (parallel)
kubectl logs deployment/myapp --all-containers --prefix

# Logs with timestamps — essential for correlating with external events
kubectl logs myapp-pod --timestamps

# Logs from a specific time window
kubectl logs myapp-pod --since=1h
kubectl logs myapp-pod --since-time=2026-04-07T10:00:00Z

# Ephemeral debug container for distroless images (K8s 1.23+)
kubectl debug -it myapp-pod --image=busybox --target=app-container

# Debug a node by creating a privileged debug Pod
kubectl debug node/my-node -it --image=ubuntu

# Copy logs from a crashed pod before it is garbage collected
kubectl logs <pod> --previous > crash.log 2>&1

# Stream logs from multiple pods with a label selector
kubectl logs -l app=payment-service --all-containers --prefix --follow

# Check what environment variables a running pod has
kubectl exec myapp-pod -- printenv | sort

# Test network connectivity from inside a pod
kubectl exec myapp-pod -- curl -s http://other-service.default.svc.cluster.local:8080/health
kubectl exec myapp-pod -- nslookup other-service.default.svc.cluster.local

# Check mounted volumes and config
kubectl exec myapp-pod -- df -h
kubectl exec myapp-pod -- mount | grep config

# Apply config
kubectl apply -f deployment.yaml
kubectl apply -f ./k8s/              # apply all files in directory

# Update image
kubectl set image deployment/myapp api=myapp:2.0

# Scale
kubectl scale deployment myapp --replicas=5

# Rollout management
kubectl rollout status deployment/myapp
kubectl rollout history deployment/myapp
kubectl rollout undo deployment/myapp                    # rollback one step
kubectl rollout undo deployment/myapp --to-revision=2    # rollback to specific revision

# Delete
kubectl delete pod myapp-pod
kubectl delete deployment myapp
kubectl delete -f deployment.yaml   # delete what was applied

# Force delete a stuck pod
kubectl delete pod myapp-pod --force --grace-period=0

# ── PRODUCTION-GRADE DEPLOYMENT MANAGEMENT ───────────────────────────────

# Apply with server-side diff (dry-run) — see what would change
kubectl apply -f deployment.yaml --server-dry-run --diff

# Apply with field validation — reject invalid manifests
kubectl apply -f deployment.yaml --validate=true --server-side

# Restart all pods in a deployment (rolling restart)
kubectl rollout restart deployment/myapp

# Pause a rollout mid-way (canary testing)
kubectl rollout pause deployment/myapp
# ... verify canary pods ...
kubectl rollout resume deployment/myapp

# Check rollout revision details
kubectl rollout history deployment/myapp --revision=3

# Scale with resource-aware scripting
CURRENT=$(kubectl get deployment myapp -o jsonpath='{.spec.replicas}')
DESIRED=$((CURRENT + 2))
kubectl scale deployment myapp --replicas=$DESIRED
echo "Scaled from $CURRENT to $DESIRED replicas"

# Delete with label selector (dangerous — always dry-run first)
kubectl delete pods -l app=temp-worker --dry-run=client
kubectl delete pods -l app=temp-worker

# Apply with pruning — delete resources not in the applied set
kubectl apply -f ./k8s/ --prune -l app=myapp

# Export current state before making changes (safety myapp-backup-$(date +%Y%m%d-%H%M%S).yaml