Kubernetes

Essential kubectl commands and Kubernetes patterns.

Context & Namespace

# View contexts
kubectl config get-contexts
kubectl config current-context

# Switch context
kubectl config use-context production

# Set default namespace
kubectl config set-context --current --namespace=my-app

# Use namespace in command
kubectl get pods -n kube-system
kubectl get pods --all-namespaces  # or -A

Pods

# List pods
kubectl get pods
kubectl get pods -o wide              # More details
kubectl get pods -w                    # Watch mode
kubectl get pods --show-labels
kubectl get pods -l app=web            # By label

# Pod details
kubectl describe pod my-pod
kubectl get pod my-pod -o yaml

# Logs
kubectl logs my-pod
kubectl logs my-pod -f                 # Follow
kubectl logs my-pod --tail=100
kubectl logs my-pod -c my-container    # Specific container
kubectl logs my-pod --previous         # Previous crash

# Exec into pod
kubectl exec -it my-pod -- /bin/sh
kubectl exec -it my-pod -c my-container -- bash

# Port forward
kubectl port-forward my-pod 8080:80
kubectl port-forward svc/my-service 8080:80

# Copy files
kubectl cp my-pod:/app/file.txt ./file.txt
kubectl cp ./file.txt my-pod:/app/

# Delete
kubectl delete pod my-pod
kubectl delete pod my-pod --grace-period=0 --force