Container Orchestration with Kubernetes

🛠️ Step 1: Enable Kubernetes in Docker Desktop

1. Open Docker Desktop.

2. Go to Settings → Kubernetes.

3. Check “Enable Kubernetes”.

4. Click Apply & Restart.

5. Wait until Docker Desktop shows Kubernetes as running (green).

Test:

kubectl cluster-info
kubectl get nodes

You should see one node named docker-desktop.

Step 2: Build and Push Your Docker Image

Since Kubernetes needs the image, push it to Docker Hub:

# Build image (replace my-flask-app with your app name)
docker build -t my-flask-app:v1 .

# Tag with Docker Hub username
docker tag my-flask-app:v1 your-dockerhub-username/my-flask-app:v1

# Login and push
docker login
docker push your-dockerhub-username/my-flask-app:v1

Step 3: Create Deployment YAML

Create folder k8s-manifests/ → inside it create web-deployment.yaml:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: web-app-deployment
  labels:
    app: web-app
spec:
  replicas: 2
  selector:
    matchLabels:
      app: web-app
  template:
    metadata:
      labels:
        app: web-app
    spec:
      containers:
      - name: web-app-container
        image: your-dockerhub-username/my-flask-app:v1  # replace with your image
        ports:
        - containerPort: 5000  # replace with your app’s port

Step 4: Create Service YAML

So you can access your app from browser.Create web-service.yaml in same folder:

apiVersion: v1
kind: Service
metadata:
  name: web-app-service
spec:
  selector:
    app: web-app
  ports:
    - protocol: TCP
      port: 80
      targetPort: 5000   # must match containerPort
  type: LoadBalancer

Step 5: Apply Deployment & Service

Run:

kubectl apply -f k8s-manifests/web-deployment.yaml
kubectl apply -f k8s-manifests/web-service.yaml

Check:

kubectl get pods
kubectl get svc

You should see:

• 2 pods running from your deployment.

• Service of type LoadBalancer with a cluster IP.

Step 6: Access the App

Since Docker Desktop doesn’t provide a real cloud load balancer, it maps the service to localhost.Check with:

kubectl port-forward svc/web-app-service 8080:80

Now open → http://localhost:8080 🎉

Step 7: Clean Up

kubectl delete -f k8s-manifests/web-deployment.yaml
kubectl delete -f k8s-manifests/web-service.yaml