Kubernetes for Beginners: Where to Start in 2026

#!/usr/bin/env bash
# Requires Docker, kind and kubectl installed
set -euo pipefail
kind create cluster --name learn
kubectl cluster-info --context kind-learn
kubectl get nodes
kubectl get pods -A          # system pods that run the cluster
# Delete when finished:
# kind delete cluster --name learn

kubectl get nodes                 # cluster machines
kubectl get pods                  # pods in the default namespace
kubectl get all                   # common objects
kubectl describe pod <name>       # details and events
kubectl logs <pod-name>           # container logs
kubectl exec -it <pod-name> -- sh # shell inside a container
kubectl apply -f app.yaml         # create or update from YAML
kubectl delete -f app.yaml        # remove those objects

apiVersion: apps/v1
kind: Deployment
metadata:
  name: hello
spec:
  replicas: 2
  selector:
    matchLabels: { app: hello }
  template:
    metadata:
      labels: { app: hello }
    spec:
      containers:
        - name: web
          image: nginx:1.27
          ports: [{ containerPort: 80 }]
---
apiVersion: v1
kind: Service
metadata:
  name: hello
spec:
  selector: { app: hello }
  ports:
    - port: 80
      targetPort: 80

#!/usr/bin/env bash
set -euo pipefail
kubectl apply -f app.yaml
kubectl rollout status deployment/hello
kubectl get deploy,pods,svc -l app=hello

# Self-healing: delete the pods and watch new ones replace them
kubectl delete pod -l app=hello
kubectl rollout status deployment/hello
kubectl get pods -l app=hello

# Reach the service from your laptop
kubectl port-forward svc/hello 8080:80 >/dev/null &
PF_PID=$!
sleep 2
curl -s localhost:8080 | head -5
kill "$PF_PID"

apiVersion: v1
kind: ConfigMap
metadata:
  name: hello-config
data:
  APP_MODE: "production"
---
apiVersion: v1
kind: Secret
metadata:
  name: hello-secret
type: Opaque
stringData:
  DB_PASSWORD: "change-me"   # practice only; use a secrets manager in real systems

spec:
  template:
    spec:
      containers:
        - name: web
          image: nginx:1.27
          envFrom:
            - configMapRef: { name: hello-config }
            - secretRef: { name: hello-secret }
          readinessProbe:
            httpGet: { path: /, port: 80 }
            periodSeconds: 5
          livenessProbe:
            httpGet: { path: /, port: 80 }
            initialDelaySeconds: 10
          resources:
            requests: { cpu: 100m, memory: 64Mi }
            limits: { cpu: 250m, memory: 128Mi }
# Scale: kubectl scale deployment hello --replicas=3

Week 1  Docker refresher, YAML, kind or minikube, kubectl basics
Week 2  Pods, Deployments, Services, labels, namespaces
Week 3  ConfigMaps, Secrets, probes, requests and limits, scaling
Week 4  Practice project, troubleshooting drills, notes

Later: Ingress, Helm, persistent volumes, HPA, a managed cloud cluster

Project: Deploy your own containerised API on kind

- Build the image and load it into kind (kind load docker-image)
- Deployment with 2 replicas, probes and resources
- Service and port-forward to test
- ConfigMap for settings, Secret for a password
- Rolling update to a new image tag, then rollback
- README with commands and a simple diagram

Practise fixing these on purpose:

1. Wrong image tag        -> Pod in ImagePullBackOff
2. App crashes on start   -> CrashLoopBackOff; read kubectl logs
3. Service selector typo  -> no endpoints; kubectl get endpoints
4. Bad readiness path     -> Pod never Ready; kubectl describe
5. Too-low memory limit   -> OOMKilled; check events

Write down the symptom, command used and fix for each.