🔧 Bài 25: Troubleshooting Kubernetes

# 1. Xem status pods
kubectl get pods -o wide

# 2. Describe để xem events
kubectl describe pod my-pod

# 3. Xem logs
kubectl logs my-pod
kubectl logs my-pod --previous    # crashed container

# 4. Exec vào pod
kubectl exec -it my-pod -- /bin/sh

# Debug với ephemeral container
kubectl debug my-pod -it --image=busybox

# Debug copy của pod (không ảnh hưởng original)
kubectl debug my-pod -it --copy-to=my-pod-debug --container=debugger --image=busybox

# Debug node
kubectl debug node/my-node -it --image=busybox

# Test DNS
kubectl run test --image=busybox -it --rm -- nslookup my-service

# Test connectivity
kubectl run test --image=busybox -it --rm -- wget -qO- http://my-service

# Check endpoints
kubectl get endpoints my-service

# Check service
kubectl describe service my-service

# Xem resource usage
kubectl top pods
kubectl top nodes

# Xem events
kubectl get events --sort-by='.lastTimestamp'

# Check resource quota
kubectl describe resourcequota -n my-namespace