Kubernetes Cheat Sheet

Container orchestration. Pods, deployments, services, debugging.

Quick Reference

Resource	Purpose	Key Commands
Pod	Smallest deployable unit, one or more containers	get, describe, logs
Deployment	Manages ReplicaSets, handles rollouts	apply, scale, rollout
Service	Stable network endpoint for pods	expose, port-forward
ConfigMap	Configuration data as key-value pairs	create configmap
Secret	Sensitive data (base64 encoded)	create secret
Namespace	Virtual cluster for resource isolation	-n, --all-namespaces

Cluster Context

kubectl cluster-info                  # Display cluster info
kubectl version                       # Client and server version
kubectl get nodes                     # List nodes in cluster
kubectl get nodes -o wide             # With IP addresses

# Context management
kubectl config current-context        # Show current context
kubectl config get-contexts           # List all contexts
kubectl config use-context <name>     # Switch context
kubectl config set-context --current --namespace=<ns>  # Set default namespace

Viewing Resources

# Basic listing
kubectl get pods                      # Pods in current namespace
kubectl get pods -n <namespace>       # Pods in specific namespace
kubectl get pods -A                   # Pods across all namespaces
kubectl get pods -o wide              # With node and IP info
kubectl get pods -w                   # Watch for changes

# Multiple resource types
kubectl get all                       # Common resources
kubectl get pods,svc,deploy           # Specific types
kubectl get all -A                    # Everything everywhere

# Output formats
kubectl get pods -o yaml              # YAML output
kubectl get pods -o json              # JSON output
kubectl get pods -o name              # Just names

# Describe for details
kubectl describe pod <name>           # Detailed pod info with events
kubectl describe node <name>          # Node details
kubectl describe deploy <name>        # Deployment details

Pods

# Run a pod
kubectl run nginx --image=nginx       # Create pod imperatively
kubectl run debug --image=busybox -it --rm -- sh  # Temporary debug pod

# Logs
kubectl logs <pod>                    # View logs
kubectl logs <pod> -c <container>     # Specific container
kubectl logs <pod> --previous         # Previous container instance
kubectl logs <pod> -f                 # Follow/stream logs
kubectl logs <pod> --tail=100         # Last 100 lines
kubectl logs -l app=nginx             # By label selector

# Execute commands
kubectl exec <pod> -- ls /app         # Run command in pod
kubectl exec -it <pod> -- /bin/sh     # Interactive shell
kubectl exec -it <pod> -c <container> -- sh  # Specific container

# Copy files
kubectl cp <pod>:/path ./local        # From pod to local
kubectl cp ./local <pod>:/path        # From local to pod

# Port forwarding
kubectl port-forward <pod> 8080:80    # Forward local:pod
kubectl port-forward svc/<name> 8080:80  # Forward to service

Deployments

# Create
kubectl create deployment nginx --image=nginx
kubectl create deployment nginx --image=nginx --replicas=3

# Apply from manifest
kubectl apply -f deployment.yaml      # Create or update
kubectl apply -f ./manifests/         # All files in directory
kubectl apply -f https://url/manifest.yaml  # From URL

# Scale
kubectl scale deploy <name> --replicas=5
kubectl autoscale deploy <name> --min=2 --max=10 --cpu-percent=80

# Update image (rolling update)
kubectl set image deploy/<name> <container>=<image:tag>
kubectl set image deploy/nginx nginx=nginx:1.25

# Rollout management
kubectl rollout status deploy/<name>  # Watch rollout progress
kubectl rollout history deploy/<name> # View history
kubectl rollout undo deploy/<name>    # Rollback to previous
kubectl rollout undo deploy/<name> --to-revision=2  # Specific revision
kubectl rollout restart deploy/<name> # Restart all pods
kubectl rollout pause deploy/<name>   # Pause rollout
kubectl rollout resume deploy/<name>  # Resume rollout

Services

# Expose deployment
kubectl expose deploy <name> --port=80 --target-port=8080
kubectl expose deploy <name> --type=NodePort --port=80
kubectl expose deploy <name> --type=LoadBalancer --port=80

# Types
# ClusterIP  — internal only (default)
# NodePort   — exposed on each node's IP at static port
# LoadBalancer — external load balancer (cloud/OrbStack)

# Get endpoints
kubectl get endpoints <service>
kubectl get svc <name> -o wide

ConfigMaps & Secrets

# ConfigMap
kubectl create configmap <name> --from-literal=key=value
kubectl create configmap <name> --from-file=config.properties
kubectl create configmap <name> --from-env-file=.env
kubectl get configmap <name> -o yaml

# Secrets
kubectl create secret generic <name> --from-literal=password=secret
kubectl create secret generic <name> --from-file=./credentials
kubectl create secret docker-registry <name> \
  --docker-server=<url> --docker-username=<user> --docker-password=<pass>

# View secret (base64 decoded)
kubectl get secret <name> -o jsonpath='{.data.password}' | base64 -d

Namespaces

kubectl get namespaces                # List namespaces
kubectl create namespace <name>       # Create namespace
kubectl delete namespace <name>       # Delete (and all resources in it)

# Set default namespace
kubectl config set-context --current --namespace=<name>

# Shorthand for namespace flag
kubectl get pods -n kube-system
kubectl get pods --all-namespaces     # or -A

Labels & Selectors

# Add/update labels
kubectl label pod <name> env=prod
kubectl label pod <name> env=staging --overwrite

# Remove label
kubectl label pod <name> env-

# Select by label
kubectl get pods -l app=nginx
kubectl get pods -l 'env in (prod,staging)'
kubectl get pods -l app=nginx,env=prod
kubectl delete pods -l app=test

Debugging

The Workflow: get → describe → logs

# 1. Get overview — what's the status?
kubectl get pods
kubectl get events --sort-by='.lastTimestamp'

# 2. Describe — what happened? (scheduling, mounts, probes)
kubectl describe pod <name>

# 3. Logs — what's the app saying?
kubectl logs <pod> --tail=50
kubectl logs <pod> --previous        # If container restarted

Common Pod States

State	Meaning	Check
Pending	Not scheduled yet	describe for events
ContainerCreating	Pulling image or mounting volumes	describe for events
ImagePullBackOff	Can’t pull image	Image name, registry auth
CrashLoopBackOff	Container keeps crashing	logs --previous
Running	Container is running	May still be unhealthy
Terminating	Being deleted	Finalizers, stuck processes

Debug Commands

# Check pod events
kubectl describe pod <name> | grep -A 20 Events

# Check resource usage
kubectl top pods
kubectl top nodes

# Debug with ephemeral container (k8s 1.23+)
kubectl debug -it <pod> --image=busybox --target=<container>

# Run debug pod in same namespace
kubectl run debug --image=nicolaka/netshoot -it --rm -- /bin/bash

# Check DNS resolution
kubectl run test --image=busybox -it --rm -- nslookup kubernetes

# Check service connectivity
kubectl run test --image=curlimages/curl -it --rm -- curl http://<service>:<port>

Local Development with OrbStack

OrbStack provides a lightweight local Kubernetes cluster on macOS.

Setup

# Enable Kubernetes in OrbStack settings, or:
orb start k8s                         # Start cluster
orb stop k8s                          # Stop cluster
orb restart k8s                       # Restart cluster
orb delete k8s                        # Delete cluster

OrbStack Advantages

• 2-second startup — Fast cluster initialization
• Shared images — Built Docker images immediately available to pods
• Direct network access — All service types accessible from Mac
• Low resource usage — Battery-friendly, minimal CPU/disk

Network Access

# Services accessible directly from Mac:
# - ClusterIP:  Direct IP access
# - NodePort:   localhost:<port>
# - LoadBalancer: *.k8s.orb.local
# - Pod IPs:    Direct connection

# Example: Access a LoadBalancer service
kubectl apply -f deployment.yaml
kubectl expose deploy nginx --type=LoadBalancer --port=80
curl http://nginx.default.svc.cluster.local
# Or: curl http://<service>.k8s.orb.local

Using Local Images

# Build image (no registry push needed)
docker build -t myapp:latest .

# Use in pod (avoid :latest to prevent pull attempts)
kubectl run myapp --image=myapp:v1

# Or use imagePullPolicy: Never in manifest

Manifests

Deployment Template

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp
  labels:
    app: myapp
spec:
  replicas: 3
  selector:
    matchLabels:
      app: myapp
  template:
    metadata:
      labels:
        app: myapp
    spec:
      containers:
        - name: myapp
          image: myapp:1.0
          ports:
            - containerPort: 8080
          env:
            - name: ENV_VAR
              value: "value"
          resources:
            requests:
              memory: "64Mi"
              cpu: "250m"
            limits:
              memory: "128Mi"
              cpu: "500m"
          livenessProbe:
            httpGet:
              path: /health
              port: 8080
            initialDelaySeconds: 10
            periodSeconds: 5
          readinessProbe:
            httpGet:
              path: /ready
              port: 8080
            initialDelaySeconds: 5
            periodSeconds: 3

Service Template

apiVersion: v1
kind: Service
metadata:
  name: myapp
spec:
  selector:
    app: myapp
  ports:
    - port: 80
      targetPort: 8080
  type: ClusterIP # or NodePort, LoadBalancer

Useful Aliases

# Add to ~/.bashrc or ~/.zshrc
alias k='kubectl'
alias kgp='kubectl get pods'
alias kgs='kubectl get svc'
alias kgd='kubectl get deploy'
alias kga='kubectl get all'
alias kd='kubectl describe'
alias kl='kubectl logs'
alias ke='kubectl exec -it'
alias kaf='kubectl apply -f'
alias kdf='kubectl delete -f'

# Shell completion
source <(kubectl completion bash)  # or zsh

Deleting Resources

kubectl delete pod <name>             # Delete pod
kubectl delete deploy <name>          # Delete deployment
kubectl delete svc <name>             # Delete service
kubectl delete -f manifest.yaml       # Delete from file

kubectl delete pods --all             # All pods in namespace
kubectl delete all --all              # All common resources
kubectl delete all -l app=test        # By label

# Force delete stuck pod
kubectl delete pod <name> --force --grace-period=0

See Also

• Docker — Container basics before orchestration
• Shell — Scripting for kubectl automation
• jq — Processing kubectl JSON output
• PostgreSQL
• System Design