🌐 Three-Tier Application on Amazon EKS

This project deploys a full-stack React + Node.js + MongoDB application to Amazon EKS (Elastic Kubernetes Service) using:

• Docker
• Kubernetes (k8s)
• AWS Load Balancer Controller (ALB)
• GitHub Actions (CI/CD)
• Prometheus & Grafana (Monitoring)

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📐 Architecture Overview

Layer	Tech Stack
Frontend	React (Dockerized)
Backend	Node.js (Express API)
Database	MongoDB
Platform	Amazon EKS (t2.medium nodes)
Ingress	AWS ALB Controller
Monitoring	Prometheus & Grafana

Namespaces

• three-tier: App components
• kube-system: Controllers
• workshop: (Optional/testing)

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🚀 Deployment Guide

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🧱 Part 1: Create the EKS Cluster

eksctl create cluster \
  --name three-tier-cluster \
  --region us-west-2 \
  --node-type t2.medium \
  --nodes-min 2 \
  --nodes-max 2 \
  --managed

aws eks update-kubeconfig --name three-tier-cluster --region us-west-2

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🔐 Part 2: IAM & Load Balancer Controller

eksctl utils associate-iam-oidc-provider \
  --region us-west-2 \
  --cluster three-tier-cluster \
  --approve

curl -O https://raw.githubusercontent.com/kubernetes-sigs/aws-load-balancer-controller/v2.5.4/docs/install/iam_policy.json

aws iam create-policy \
  --policy-name AWSLoadBalancerControllerIAMPolicyThreeTier \
  --policy-document file://iam_policy.json

eksctl create iamserviceaccount \
  --cluster=three-tier-cluster \
  --namespace=kube-system \
  --name=aws-load-balancer-controller \
  --attach-policy-arn=arn:aws:iam::<ACCOUNT_ID>:policy/AWSLoadBalancerControllerIAMPolicyThreeTier \
  --approve \
  --override-existing-serviceaccounts \
  --region=us-west-2

helm repo add eks https://aws.github.io/eks-charts
helm repo update

helm install aws-load-balancer-controller eks/aws-load-balancer-controller \
  -n kube-system \
  --set clusterName=three-tier-cluster \
  --set serviceAccount.create=false \
  --set serviceAccount.name=aws-load-balancer-controller \
  --set region=us-west-2

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🐳 Part 3: Dockerize and Push Images to Amazon ECR

# Frontend
docker build -t three-tier-frontend ./Application-Code/frontend
docker tag three-tier-frontend:latest <ACCOUNT_ID>.dkr.ecr.us-west-2.amazonaws.com/three-tier-frontend
docker push <ACCOUNT_ID>.dkr.ecr.us-west-2.amazonaws.com/three-tier-frontend

# Backend
docker build -t three-tier-backend ./Application-Code/backend
docker tag three-tier-backend:latest <ACCOUNT_ID>.dkr.ecr.us-west-2.amazonaws.com/three-tier-backend
docker push <ACCOUNT_ID>.dkr.ecr.us-west-2.amazonaws.com/three-tier-backend

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📦 Part 4: Kubernetes Deployment

# Create namespaces
kubectl create namespace three-tier
kubectl create namespace workshop

# MongoDB
cd Kubernetes-Manifests-file/Database
kubectl apply -f secrets.yaml -n three-tier
kubectl apply -f pv.yaml -n three-tier
kubectl apply -f pvc.yaml -n three-tier
kubectl apply -f deployment.yaml -n three-tier
kubectl apply -f service.yaml -n three-tier

# Backend
cd ../Backend
kubectl apply -f deployment.yaml -n three-tier
kubectl apply -f service.yaml -n three-tier

# Frontend
cd ../Frontend
kubectl apply -f deployment.yaml -n three-tier
kubectl apply -f service.yaml -n three-tier

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🌐 Part 5: Ingress with AWS ALB

# ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: mainlb
  namespace: three-tier
  annotations:
    alb.ingress.kubernetes.io/scheme: internet-facing
    alb.ingress.kubernetes.io/target-type: ip
    alb.ingress.kubernetes.io/backend-protocol: HTTP
    alb.ingress.kubernetes.io/listen-ports: '[{"HTTP": 80}]'
    kubernetes.io/ingress.class: alb
spec:
  rules:
    - http:
        paths:
          - path: /*
            pathType: ImplementationSpecific
            backend:
              service:
                name: frontend-service
                port:
                  number: 80

kubectl apply -f ingress.yaml

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🔄 Part 6: GitHub Actions CI/CD

Add this to .github/workflows/deploy.yml

name: CI/CD Pipeline for Three-Tier App

on:
  push:
    branches: [ main ]

jobs:
  build-and-deploy:
    runs-on: ubuntu-latest

    env:
      ECR_REGISTRY: <ACCOUNT_ID>.dkr.ecr.us-west-2.amazonaws.com

    steps:
    - name: Checkout code
      uses: actions/checkout@v3

    - name: Configure AWS credentials
      uses: aws-actions/configure-aws-credentials@v2
      with:
        aws-access-key-id: ${{ secrets.AWS_ACCESS_KEY_ID }}
        aws-secret-access-key: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
        aws-region: us-west-2

    - name: Login to Amazon ECR
      run: |
        aws ecr get-login-password --region us-west-2 \
        | docker login --username AWS --password-stdin $ECR_REGISTRY

    - name: Build and Push Frontend Image
      run: |
        docker build -t three-tier-frontend ./Application-Code/frontend
        docker tag three-tier-frontend:latest $ECR_REGISTRY/three-tier-frontend:latest
        docker push $ECR_REGISTRY/three-tier-frontend:latest

    - name: Build and Push Backend Image
      run: |
        docker build -t three-tier-backend ./Application-Code/backend
        docker tag three-tier-backend:latest $ECR_REGISTRY/three-tier-backend:latest
        docker push $ECR_REGISTRY/three-tier-backend:latest

    - name: Deploy to EKS
      run: |
        aws eks update-kubeconfig --region us-west-2 --name three-tier-cluster
        kubectl apply -f Kubernetes-Manifests-file/

Amazon EKS Deployment: Three-Tier Architecture Guide (Checkout full Medium guide for code).

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📊 Part 7: Monitoring with Prometheus & Grafana

kubectl create ns monitoring

helm repo add prometheus-community https://prometheus-community.github.io/helm-charts
helm install prometheus prometheus-community/prometheus -n monitoring

helm repo add grafana https://grafana.github.io/helm-charts
helm install grafana grafana/grafana -n monitoring --set adminPassword=admin123 --set service.type=LoadBalancer

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🛡 Part 8: Security Best Practices

• Use AWS Secrets Manager with CSI
• Use HTTPS + ACM certs
• Enable AWS WAF
• Apply NetworkPolicies
• Restrict IAM roles

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🧹 Cleanup

kubectl delete ns three-tier monitoring workshop
helm uninstall grafana -n monitoring
helm uninstall prometheus -n monitoring
eksctl delete cluster --name three-tier-cluster --region us-west-2

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🙌 Credits

Inspired by LondheShubham153/TWSThreeTierAppChallenge