K8s Cluster Manager

1. Pod Lifecycle Management

Listing Pods

Show pods with useful context (status, restarts, age, node placement):

# All pods in a namespace with wide output
kubectl get pods -n <namespace> -o wide

# All pods across all namespaces
kubectl get pods --all-namespaces -o wide

# Filter by label
kubectl get pods -n <namespace> -l app=<label>

# Watch for changes in real-time
kubectl get pods -n <namespace> -w

Inspecting a Pod

When a user asks "why is my pod failing?" or "what's wrong with this pod?", follow this diagnostic sequence:

1. Get status overview: kubectl get pod <name> -n <ns> -o wide
2. Describe for events: kubectl describe pod <name> -n <ns> — look at the Events section at the bottom
3. Check logs: kubectl logs <name> -n <ns> --tail=200
4. Previous container logs (if restarting): kubectl logs <name> -n <ns> --previous
5. Multi-container pods: kubectl logs <name> -n <ns> -c <container>

Common Pod Failure Patterns

Creating Pods

When the user wants to deploy a pod from a YAML manifest:

# Apply a manifest
kubectl apply -f <manifest.yaml>

# Create from image directly (quick testing only)
kubectl run <name> --image=<image> -n <ns>

# Dry-run to validate before applying
kubectl apply -f <manifest.yaml> --dry-run=client

When generating YAML manifests, always include:

• metadata.labels for identification
• resources.requests and resources.limits for CPU/memory
• securityContext.runAsNonRoot: true unless root is explicitly needed
• restartPolicy appropriate to the workload

Deleting Pods

# Delete a single pod
kubectl delete pod <name> -n <ns>

# Delete pods by label
kubectl delete pods -l app=<label> -n <ns>

# Force delete a stuck pod (use with caution)
kubectl delete pod <name> -n <ns> --grace-period=0 --force

Always warn the user before force-deleting. Explain that force-delete skips graceful shutdown and the workload may not clean up properly.

Exec and Debugging

# Interactive shell
kubectl exec -it <pod> -n <ns> -- /bin/sh

# Run a specific command
kubectl exec <pod> -n <ns> -- <command>

# Ephemeral debug container (K8s 1.23+)
kubectl debug -it <pod> -n <ns> --image=busybox --target=<container>

2. Deployments & Services

Deployments

# List deployments
kubectl get deployments -n <ns>

# Deployment details (includes replica sets and rollout history)
kubectl describe deployment <name> -n <ns>

# Scale replicas
kubectl scale deployment <name> --replicas=<N> -n <ns>

# Update image (triggers rolling update)
kubectl set image deployment/<name> <container>=<new-image> -n <ns>

# Check rollout status
kubectl rollout status deployment/<name> -n <ns>

# View rollout history
kubectl rollout history deployment/<name> -n <ns>

# Rollback to previous revision
kubectl rollout undo deployment/<name> -n <ns>

# Rollback to specific revision
kubectl rollout undo deployment/<name> --to-revision=<N> -n <ns>

# Restart all pods in a deployment (rolling restart)
kubectl rollout restart deployment/<name> -n <ns>

Services

# List services
kubectl get svc -n <ns>

# Service details (endpoints, ports)
kubectl describe svc <name> -n <ns>

# Expose a deployment as a service
kubectl expose deployment <name> --port=<port> --target-port=<target> --type=ClusterIP -n <ns>

# Delete a service
kubectl delete svc <name> -n <ns>

When the user asks to "expose" or "make accessible" a deployment, ask what type of service they need:

• ClusterIP (default): internal-only, reachable within the cluster
• NodePort: accessible on each node's IP at a static port
• LoadBalancer: provisions an external load balancer (cloud environments)

Ingress

# List ingress resources
kubectl get ingress -n <ns>

# Describe ingress
kubectl describe ingress <name> -n <ns>

3. Cluster Health & Node Diagnostics

Cluster Overview

# Cluster info
kubectl cluster-info

# Component status (etcd, scheduler, controller-manager)
kubectl get componentstatuses

# API server health
kubectl get --raw='/healthz'

Node Management

# List nodes with status and resource info
kubectl get nodes -o wide

# Detailed node info (capacity, allocatable, conditions, taints)
kubectl describe node <name>

# Node resource usage (requires metrics-server)
kubectl top nodes

# Pod resource usage
kubectl top pods -n <ns>

Node Maintenance

When a user needs to take a node out of rotation for maintenance:

# 1. Cordon — mark node as unschedulable (no new pods)
kubectl cordon <node>

# 2. Drain — evict existing pods gracefully
kubectl drain <node> --ignore-daemonsets --delete-emptydir-data

# 3. Perform maintenance...

# 4. Uncordon — mark node as schedulable again
kubectl uncordon <node>

Warn the user that drain will evict all non-DaemonSet pods. Pods managed by a Deployment/ReplicaSet will be rescheduled on other nodes; standalone pods will be deleted.

Troubleshooting Node Issues

4. Namespaces & Resource Isolation

Namespace Management

# List namespaces
kubectl get namespaces

# Create namespace
kubectl create namespace <name>

# Delete namespace (deletes ALL resources within it)
kubectl delete namespace <name>

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

Always confirm with the user before deleting a namespace — this is destructive and removes everything in it.

Resource Quotas

# View quotas in a namespace
kubectl get resourcequotas -n <ns>

# Describe quota details
kubectl describe resourcequota <name> -n <ns>

When creating a resource quota manifest:

apiVersion: v1