Kubernetes Hands-on Project (Minikube)

This repository demonstrates a complete hands-on implementation of core Kubernetes concepts including deployment, scaling, load balancing, and observability using Minikube.

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Objectives

• Understand Kubernetes architecture and components
• Deploy containerized applications using Pods and Deployments
• Implement auto-healing and scaling
• Perform rolling updates and rollback
• Expose applications using Services
• Demonstrate load balancing across multiple pods
• Monitor traffic distribution using K9s

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Tech Stack

• Kubernetes
• Minikube
• Docker
• kubectl
• K9s
• YAML

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Project Structure

kubernetes-practice/
│
├── pod/
│   └── nginx-pod.yaml
│
├── deployment/
│   └── nginx-deployment.yaml
│
├── service-nodeport/
│   └── nginx-service.yaml
│
├── load-balancing/
│   ├── nginx-lb-test.yaml
│   └── nginx-lb-test-service.yaml
│
├── observability/
│   └── notes.md
│
└── README.md

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1. Pod Creation

nginx-pod.yaml

apiVersion: v1
kind: Pod
metadata:
  name: nginx-pod
spec:
  containers:
  - name: nginx-container
    image: nginx
    ports:
    - containerPort: 80

Commands

kubectl apply -f nginx-pod.yaml
kubectl get pods

Access (Port Forward)

kubectl port-forward pod/nginx-pod 8080:80
curl localhost:8080

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2. Deployment (Auto-Healing & Scaling)

nginx-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx-container
        image: nginx
        ports:
        - containerPort: 80

Commands

kubectl apply -f nginx-deployment.yaml
kubectl get deployments
kubectl get pods

Auto-Healing Test

kubectl delete pod <pod-name>

Kubernetes automatically recreates the deleted pod.

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📈 3. Scaling

kubectl scale deployment nginx-deployment --replicas=5
kubectl get pods

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🔁 4. Rolling Updates & Rollback

Update Image

kubectl set image deployment/nginx-deployment nginx-container=nginx:1.25

Watch Update

kubectl get pods -w

Rollback

kubectl rollout undo deployment nginx-deployment

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5. Service (NodePort)

nginx-service.yaml

apiVersion: v1
kind: Service
metadata:
  name: nginx-service
spec:
  type: NodePort
  selector:
    app: nginx
  ports:
    - port: 80
      targetPort: 80
      nodePort: 30007

Commands

kubectl apply -f nginx-service.yaml
kubectl get services
minikube ip

Access

curl <minikube-ip>:30007

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6. Load Balancing Demonstration

Custom Deployment (Returns Pod Name)

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-lb-test
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx-lb-test
  template:
    metadata:
      labels:
        app: nginx-lb-test
    spec:
      containers:
      - name: nginx
        image: nginx
        command: ["/bin/sh", "-c"]
        args:
          - echo "Hello from $(hostname)" > /usr/share/nginx/html/index.html && nginx -g 'daemon off;'
        ports:
        - containerPort: 80

---

Service

apiVersion: v1
kind: Service
metadata:
  name: nginx-lb-test-service
spec:
  type: NodePort
  selector:
    app: nginx-lb-test
  ports:
    - port: 80
      targetPort: 80
      nodePort: 30008

---

Test Load Balancing

for i in {1..10}; do curl <minikube-ip>:30008; done

Output

Hello from nginx-lb-test-abc123
Hello from nginx-lb-test-def456
Hello from nginx-lb-test-xyz789

This confirms traffic is distributed across multiple pods.

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7. Observability (K9s)

Run K9s

k9s

View Logs

• Select Pod
• Press l

Generate Traffic

for i in {1..20}; do curl <minikube-ip>:30008; done

Logs will show requests hitting different pods.

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Key Learnings

• Kubernetes ensures high availability using ReplicaSets
• Deployments provide auto-healing and scaling
• Rolling updates ensure zero downtime
• Services provide internal load balancing
• NodePort exposes applications externally
• Observability tools help in debugging and monitoring

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❗ Common Issues & Fixes

Issue	Fix
Pod not accessible	Use port-forward
Connection refused	Restart Minikube
Wrong logs	Check correct pod labels
Download issues	Use browser instead of curl
File not found	Verify filename before extraction

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Future Enhancements

• Implement Ingress Controller
• Use ConfigMaps and Secrets
• Deploy on AWS EKS / GCP GKE
• Implement CI/CD pipeline

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Author

Bhoopendra Singh Bhadauria