Kubernetes Operations

Expert knowledge for Kubernetes cluster management, deployment, and troubleshooting with mastery of kubectl and cloud-native patterns.

Core Expertise

Kubernetes Operations

• Workload Management: Deployments, StatefulSets, DaemonSets, Jobs, and CronJobs

• Networking: Services, Ingress, NetworkPolicies, and DNS configuration

• Configuration & Storage: ConfigMaps, Secrets, PersistentVolumes, and PersistentVolumeClaims

• Troubleshooting: Debugging pods, analyzing logs, and inspecting cluster events

Cluster Operations Process

• Manifest First: Always prefer declarative YAML manifests for resource management

• Validate & Dry-Run: Use kubectl apply --dry-run=client to validate changes

• Inspect & Verify: After applying changes, verify with kubectl get , kubectl describe , kubectl logs

• Monitor Health: Continuously check status of nodes, pods, and services

• Clean Up: Ensure old or unused resources are properly garbage collected

Essential Commands

Resource management

kubectl apply -f manifest.yaml kubectl get pods -A kubectl describe pod <pod-name> kubectl logs -f <pod-name> kubectl exec -it <pod-name> -- /bin/bash

Debugging

kubectl get events --sort-by='.lastTimestamp' kubectl top nodes kubectl top pods --containers kubectl port-forward <pod-name> 8080:80

Deployment management

kubectl rollout status deployment/<name> kubectl rollout history deployment/<name> kubectl rollout undo deployment/<name>

Cluster inspection

kubectl cluster-info kubectl get nodes -o wide kubectl api-resources

Key Debugging Patterns

Pod Debugging

Pod inspection

kubectl describe pod <pod-name> kubectl get pod <pod-name> -o yaml kubectl logs <pod-name> --previous

Interactive debugging

kubectl exec -it <pod-name> -- /bin/bash kubectl debug <pod-name> -it --image=busybox kubectl port-forward <pod-name> 8080:80

Networking Troubleshooting

Service debugging

kubectl get svc -o wide kubectl get endpoints kubectl describe svc <service>

Network connectivity

kubectl run test-pod --image=busybox -it --rm -- sh

Inside pod: nslookup, wget, nc commands

Common Issues

CrashLoopBackOff debugging

kubectl logs <pod> --previous kubectl describe pod <pod> kubectl get events --field-selector involvedObject.name=<pod>

Resource constraints

kubectl top pod <pod> kubectl describe pod <pod> | grep -A 5 Limits

State management

kubectl state list kubectl state show <resource>

Best Practices

Context Safety (CRITICAL)

• Always specify --context explicitly in every kubectl command

• Never rely on the current context - it may have been changed by another process

• Use kubectl --context=<context-name> get pods format for all operations

• This prevents accidental operations on the wrong cluster (e.g., running production commands against staging)

CORRECT: Explicit context

kubectl --context=gke_myproject_us-central1_prod get pods kubectl --context=staging-cluster apply -f deployment.yaml

WRONG: Relying on current context

kubectl get pods # Which cluster is this targeting?

Resource Definitions

• Use declarative YAML manifests

• Implement proper labels and selectors

• Define resource requests and limits

• Configure health checks (liveness/readiness probes)

Security

• Use NetworkPolicies to restrict traffic

• Implement RBAC for access control

• Store sensitive data in Secrets

• Run containers as non-root users

Monitoring

• Configure proper logging and metrics

• Set up alerts for critical conditions

• Use health checks and readiness probes

• Monitor resource usage and quotas

Agentic Optimizations

Context Command

Pod status (structured) kubectl get pods -n <ns> -o json | jq '.items[] | {name:.metadata.name, status:.status.phase}'

Quick overview kubectl get pods -n <ns> -o wide

Events (compact) kubectl get events -n <ns> --sort-by='.lastTimestamp' -o json

Resource details kubectl get <resource> -o json

Logs (bounded) kubectl logs <pod> -n <ns> --tail=50

For detailed debugging commands, troubleshooting patterns, Helm workflows, and advanced K8s operations, see REFERENCE.md.