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Muhammad Awais Zahid
Muhammad Awais Zahid

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Complete AWS Production Lab — EKS Microservices Architecture

Architecture Overview

Internet → IGW → ALB (Public Subnet) → EKS Pods (Private Subnet)
                                              ↓
                                    PostgreSQL RDS Master
                                    (Multi-AZ Slave in AZ-2)
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Prerequisites

# Install required tools
aws --version          # AWS CLI v2
terraform --version    # Terraform >= 1.5
kubectl version        # kubectl >= 1.28
helm version           # Helm >= 3.12
eksctl version         # eksctl >= 0.160
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PHASE 1 — Terraform Backend Setup

Step 1.1 — S3 Bucket + DynamoDB for Terraform State

# backend-setup/main.tf

provider "aws" {
  region = "eu-central-1"
}

resource "aws_s3_bucket" "terraform_state" {
  bucket = "terraform-state-${data.aws_caller_identity.current.account_id}"
  force_destroy = false

  tags = { Name = "terraform-state", Environment = "production" }
}

resource "aws_s3_bucket_versioning" "state_versioning" {
  bucket = aws_s3_bucket.terraform_state.id
  versioning_configuration { status = "Enabled" }
}

resource "aws_s3_bucket_server_side_encryption_configuration" "state_encryption" {
  bucket = aws_s3_bucket.terraform_state.id
  rule {
    apply_server_side_encryption_by_default {
      sse_algorithm     = "aws:kms"
      kms_master_key_id = aws_kms_key.terraform_key.arn
    }
  }
}

resource "aws_dynamodb_table" "terraform_lock" {
  name         = "terraform-state-lock"
  billing_mode = "PAY_PER_REQUEST"
  hash_key     = "LockID"

  attribute {
    name = "LockID"
    type = "S"
  }

  tags = { Name = "terraform-state-lock" }
}

resource "aws_kms_key" "terraform_key" {
  description             = "KMS key for Terraform state encryption"
  deletion_window_in_days = 7
  enable_key_rotation     = true
}

data "aws_caller_identity" "current" {}
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cd backend-setup
terraform init
terraform apply
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Step 1.2 — Configure Terraform Backend

# backend.tf (add to main project)
terraform {
  backend "s3" {
    bucket         = "terraform-state-YOUR_ACCOUNT_ID"
    key            = "production/terraform.tfstate"
    region         = "eu-central-1"
    encrypt        = true
    dynamodb_table = "terraform-state-lock"
  }
}
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PHASE 2 — KMS Customer Managed Key

# modules/kms/main.tf

resource "aws_kms_key" "main" {
  description             = "Customer managed key for RDS, Secrets, EKS"
  deletion_window_in_days = 7
  enable_key_rotation     = true
  multi_region            = false

  policy = jsonencode({
    Version = "2012-10-17"
    Statement = [
      {
        Sid    = "Enable IAM User Permissions"
        Effect = "Allow"
        Principal = { AWS = "arn:aws:iam::${var.account_id}:root" }
        Action   = "kms:*"
        Resource = "*"
      }
    ]
  })

  tags = { Name = "production-cmk" }
}

resource "aws_kms_alias" "main" {
  name          = "alias/production-cmk"
  target_key_id = aws_kms_key.main.key_id
}

output "key_arn" { value = aws_kms_key.main.arn }
output "key_id"  { value = aws_kms_key.main.key_id }
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PHASE 3 — VPC and Networking

# modules/vpc/main.tf

resource "aws_vpc" "main" {
  cidr_block           = "10.0.0.0/16"
  enable_dns_hostnames = true
  enable_dns_support   = true
  tags = { Name = "production-vpc" }
}

# --- Subnets ---

resource "aws_subnet" "private_az1" {
  vpc_id            = aws_vpc.main.id
  cidr_block        = "10.0.1.0/24"
  availability_zone = "eu-central-1a"
  tags = {
    Name                              = "private-subnet-az1"
    "kubernetes.io/role/internal-elb" = "1"
  }
}

resource "aws_subnet" "private_az2" {
  vpc_id            = aws_vpc.main.id
  cidr_block        = "10.0.2.0/24"
  availability_zone = "eu-central-1b"
  tags = {
    Name                              = "private-subnet-az2"
    "kubernetes.io/role/internal-elb" = "1"
  }
}

resource "aws_subnet" "public_az1" {
  vpc_id                  = aws_vpc.main.id
  cidr_block              = "10.0.3.0/24"
  availability_zone       = "eu-central-1a"
  map_public_ip_on_launch = true
  tags = {
    Name                     = "public-subnet-az1"
    "kubernetes.io/role/elb" = "1"
  }
}

resource "aws_subnet" "public_az2" {
  vpc_id                  = aws_vpc.main.id
  cidr_block              = "10.0.4.0/24"
  availability_zone       = "eu-central-1b"
  map_public_ip_on_launch = true
  tags = {
    Name                     = "public-subnet-az2"
    "kubernetes.io/role/elb" = "1"
  }
}

# --- Internet Gateway ---

resource "aws_internet_gateway" "main" {
  vpc_id = aws_vpc.main.id
  tags   = { Name = "production-igw" }
}

# --- NAT Gateway ---

resource "aws_eip" "nat" {
  domain = "vpc"
  tags   = { Name = "nat-eip" }
}

resource "aws_nat_gateway" "main" {
  allocation_id = aws_eip.nat.id
  subnet_id     = aws_subnet.public_az1.id
  tags          = { Name = "production-nat" }
  depends_on    = [aws_internet_gateway.main]
}

# --- Route Tables ---

resource "aws_route_table" "public" {
  vpc_id = aws_vpc.main.id
  route {
    cidr_block = "0.0.0.0/0"
    gateway_id = aws_internet_gateway.main.id
  }
  tags = { Name = "public-rt" }
}

resource "aws_route_table" "private" {
  vpc_id = aws_vpc.main.id
  route {
    cidr_block     = "0.0.0.0/0"
    nat_gateway_id = aws_nat_gateway.main.id
  }
  tags = { Name = "private-rt" }
}

resource "aws_route_table_association" "public_az1" {
  subnet_id      = aws_subnet.public_az1.id
  route_table_id = aws_route_table.public.id
}

resource "aws_route_table_association" "public_az2" {
  subnet_id      = aws_subnet.public_az2.id
  route_table_id = aws_route_table.public.id
}

resource "aws_route_table_association" "private_az1" {
  subnet_id      = aws_subnet.private_az1.id
  route_table_id = aws_route_table.private.id
}

resource "aws_route_table_association" "private_az2" {
  subnet_id      = aws_subnet.private_az2.id
  route_table_id = aws_route_table.private.id
}

# --- VPC Flow Logs ---

resource "aws_flow_log" "main" {
  iam_role_arn    = aws_iam_role.flow_log.arn
  log_destination = aws_cloudwatch_log_group.flow_logs.arn
  traffic_type    = "ALL"
  vpc_id          = aws_vpc.main.id
}

resource "aws_cloudwatch_log_group" "flow_logs" {
  name              = "/aws/vpc/flow-logs"
  retention_in_days = 30
}

resource "aws_iam_role" "flow_log" {
  name = "vpc-flow-log-role"
  assume_role_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [{
      Action    = "sts:AssumeRole"
      Effect    = "Allow"
      Principal = { Service = "vpc-flow-logs.amazonaws.com" }
    }]
  })
}

resource "aws_iam_role_policy" "flow_log" {
  role = aws_iam_role.flow_log.id
  policy = jsonencode({
    Version = "2012-10-17"
    Statement = [{
      Effect   = "Allow"
      Action   = ["logs:CreateLogGroup", "logs:CreateLogStream", "logs:PutLogEvents"]
      Resource = "*"
    }]
  })
}
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PHASE 4 — RDS PostgreSQL (Multi-AZ)

# modules/rds/main.tf

resource "aws_db_subnet_group" "main" {
  name       = "production-db-subnet-group"
  subnet_ids = [var.private_subnet_az1_id, var.private_subnet_az2_id]
  tags       = { Name = "production-db-subnet-group" }
}

resource "aws_security_group" "rds" {
  name        = "rds-sg"
  description = "Allow PostgreSQL from EKS"
  vpc_id      = var.vpc_id

  ingress {
    from_port       = 5432
    to_port         = 5432
    protocol        = "tcp"
    security_groups = [var.eks_node_sg_id]
  }

  egress {
    from_port   = 0
    to_port     = 0
    protocol    = "-1"
    cidr_blocks = ["0.0.0.0/0"]
  }
}

resource "aws_db_instance" "master" {
  identifier              = "production-postgres-master"
  engine                  = "postgres"
  engine_version          = "15.4"
  instance_class          = "db.t3.medium"
  allocated_storage       = 20
  max_allocated_storage   = 100
  storage_type            = "gp3"
  storage_encrypted       = true
  kms_key_id              = var.kms_key_arn
  db_name                 = "productiondb"
  username                = "dbadmin"
  password                = var.db_password   # pulled from Secrets Manager
  multi_az                = true
  db_subnet_group_name    = aws_db_subnet_group.main.name
  vpc_security_group_ids  = [aws_security_group.rds.id]
  backup_retention_period = 7
  deletion_protection     = true
  skip_final_snapshot     = false
  final_snapshot_identifier = "production-final-snapshot"
  enabled_cloudwatch_logs_exports = ["postgresql", "upgrade"]

  tags = { Name = "production-postgres" }
}
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PHASE 5 — Secrets Manager

# modules/secrets/main.tf

resource "aws_secretsmanager_secret" "db_credentials" {
  name       = "production/db/credentials"
  kms_key_id = var.kms_key_arn
  tags       = { Name = "db-credentials" }
}

resource "aws_secretsmanager_secret_version" "db_credentials" {
  secret_id = aws_secretsmanager_secret.db_credentials.id
  secret_string = jsonencode({
    username = "dbadmin"
    password = var.db_password
    host     = var.rds_endpoint
    port     = 5432
    dbname   = "productiondb"
  })
}
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PHASE 6 — ECR Repositories

# modules/ecr/main.tf

locals {
  services = ["api-service", "auth-service", "document-service", "notification-service"]
}

resource "aws_ecr_repository" "services" {
  for_each             = toset(local.services)
  name                 = each.value
  image_tag_mutability = "IMMUTABLE"

  image_scanning_configuration {
    scan_on_push = true
  }

  encryption_configuration {
    encryption_type = "KMS"
    kms_key         = var.kms_key_arn
  }

  tags = { Name = each.value }
}

resource "aws_ecr_lifecycle_policy" "services" {
  for_each   = aws_ecr_repository.services
  repository = each.value.name

  policy = jsonencode({
    rules = [{
      rulePriority = 1
      description  = "Keep last 10 images"
      selection = {
        tagStatus   = "any"
        countType   = "imageCountMoreThan"
        countNumber = 10
      }
      action = { type = "expire" }
    }]
  })
}
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PHASE 7 — EKS Cluster

# modules/eks/main.tf

resource "aws_eks_cluster" "main" {
  name     = "production-eks"
  role_arn = aws_iam_role.eks_cluster.arn
  version  = "1.28"

  vpc_config {
    subnet_ids              = [var.private_subnet_az1_id, var.private_subnet_az2_id]
    endpoint_private_access = true
    endpoint_public_access  = true
    public_access_cidrs     = ["0.0.0.0/0"]
  }

  encryption_config {
    provider { key_arn = var.kms_key_arn }
    resources = ["secrets"]
  }

  enabled_cluster_log_types = ["api", "audit", "authenticator"]

  depends_on = [
    aws_iam_role_policy_attachment.eks_cluster_policy
  ]

  tags = { Name = "production-eks" }
}

resource "aws_eks_node_group" "main" {
  cluster_name    = aws_eks_cluster.main.name
  node_group_name = "production-node-group"
  node_role_arn   = aws_iam_role.eks_node.arn
  subnet_ids      = [var.private_subnet_az1_id, var.private_subnet_az2_id]
  instance_types  = ["t3.medium"]
  disk_size       = 20

  scaling_config {
    desired_size = 2
    min_size     = 1
    max_size     = 4
  }

  update_config {
    max_unavailable = 1
  }

  depends_on = [
    aws_iam_role_policy_attachment.eks_worker_node_policy,
    aws_iam_role_policy_attachment.eks_cni_policy,
    aws_iam_role_policy_attachment.ecr_read_only,
  ]
}

# --- IAM Roles ---

resource "aws_iam_role" "eks_cluster" {
  name = "eks-cluster-role"
  assume_role_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [{
      Action    = "sts:AssumeRole"
      Effect    = "Allow"
      Principal = { Service = "eks.amazonaws.com" }
    }]
  })
}

resource "aws_iam_role_policy_attachment" "eks_cluster_policy" {
  policy_arn = "arn:aws:iam::aws:policy/AmazonEKSClusterPolicy"
  role       = aws_iam_role.eks_cluster.name
}

resource "aws_iam_role" "eks_node" {
  name = "eks-node-role"
  assume_role_policy = jsonencode({
    Version = "2012-10-17"
    Statement = [{
      Action    = "sts:AssumeRole"
      Effect    = "Allow"
      Principal = { Service = "ec2.amazonaws.com" }
    }]
  })
}

resource "aws_iam_role_policy_attachment" "eks_worker_node_policy" {
  policy_arn = "arn:aws:iam::aws:policy/AmazonEKSWorkerNodePolicy"
  role       = aws_iam_role.eks_node.name
}

resource "aws_iam_role_policy_attachment" "eks_cni_policy" {
  policy_arn = "arn:aws:iam::aws:policy/AmazonEKS_CNI_Policy"
  role       = aws_iam_role.eks_node.name
}

resource "aws_iam_role_policy_attachment" "ecr_read_only" {
  policy_arn = "arn:aws:iam::aws:policy/AmazonEC2ContainerRegistryReadOnly"
  role       = aws_iam_role.eks_node.name
}
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PHASE 8 — Kubernetes Manifests (Microservices)

Step 8.1 — Namespaces and Secrets

# Connect to cluster
aws eks update-kubeconfig --region eu-central-1 --name production-eks

# Create namespace
kubectl create namespace production
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# k8s/secrets.yaml
apiVersion: v1
kind: Secret
metadata:
  name: db-credentials
  namespace: production
type: Opaque
stringData:
  DB_HOST: "your-rds-endpoint.eu-central-1.rds.amazonaws.com"
  DB_PORT: "5432"
  DB_NAME: "productiondb"
  DB_USER: "dbadmin"
  DB_PASSWORD: "your-password"   # use External Secrets Operator in production
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Step 8.2 — API Service

# k8s/api-service.yaml
apiVersion: apps/v1
kind: Deployment
metadata:
  name: api-service
  namespace: production
spec:
  replicas: 2
  selector:
    matchLabels:
      app: api-service
  template:
    metadata:
      labels:
        app: api-service
    spec:
      containers:
      - name: api-service
        image: YOUR_ACCOUNT_ID.dkr.ecr.eu-central-1.amazonaws.com/api-service:latest
        ports:
        - containerPort: 8080
        envFrom:
        - secretRef:
            name: db-credentials
        resources:
          requests:
            cpu: "100m"
            memory: "128Mi"
          limits:
            cpu: "500m"
            memory: "512Mi"
        readinessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 10
          periodSeconds: 5
        livenessProbe:
          httpGet:
            path: /health
            port: 8080
          initialDelaySeconds: 30
          periodSeconds: 10
---
apiVersion: v1
kind: Service
metadata:
  name: api-service
  namespace: production
spec:
  selector:
    app: api-service
  ports:
  - port: 80
    targetPort: 8080
  type: ClusterIP
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Step 8.3 — ALB Ingress with Path-Based Routing

# Install AWS Load Balancer Controller
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=production-eks \
  --set serviceAccount.create=true \
  --set region=eu-central-1 \
  --set vpcId=YOUR_VPC_ID
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# k8s/ingress.yaml
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: production-ingress
  namespace: production
  annotations:
    kubernetes.io/ingress.class: alb
    alb.ingress.kubernetes.io/scheme: internet-facing
    alb.ingress.kubernetes.io/target-type: ip
    alb.ingress.kubernetes.io/listen-ports: '[{"HTTP": 80}, {"HTTPS": 443}]'
    alb.ingress.kubernetes.io/ssl-redirect: '443'
spec:
  rules:
  - http:
      paths:
      - path: /api
        pathType: Prefix
        backend:
          service:
            name: api-service
            port:
              number: 80
      - path: /authentication
        pathType: Prefix
        backend:
          service:
            name: auth-service
            port:
              number: 80
      - path: /document
        pathType: Prefix
        backend:
          service:
            name: document-service
            port:
              number: 80
      - path: /notification
        pathType: Prefix
        backend:
          service:
            name: notification-service
            port:
              number: 80
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PHASE 9 — S3 File Storage with VPC Endpoint

# modules/s3/main.tf

resource "aws_s3_bucket" "file_storage" {
  bucket = "production-file-storage-${var.account_id}"
  tags   = { Name = "production-file-storage" }
}

resource "aws_s3_bucket_server_side_encryption_configuration" "file_storage" {
  bucket = aws_s3_bucket.file_storage.id
  rule {
    apply_server_side_encryption_by_default {
      sse_algorithm     = "aws:kms"
      kms_master_key_id = var.kms_key_arn
    }
  }
}

resource "aws_s3_bucket_versioning" "file_storage" {
  bucket = aws_s3_bucket.file_storage.id
  versioning_configuration { status = "Enabled" }
}

resource "aws_s3_bucket_public_access_block" "file_storage" {
  bucket                  = aws_s3_bucket.file_storage.id
  block_public_acls       = true
  block_public_policy     = true
  ignore_public_acls      = true
  restrict_public_buckets = true
}

# VPC Endpoint for private S3 access
resource "aws_vpc_endpoint" "s3" {
  vpc_id            = var.vpc_id
  service_name      = "com.amazonaws.eu-central-1.s3"
  vpc_endpoint_type = "Gateway"
  route_table_ids   = [var.private_route_table_id]
  tags              = { Name = "s3-vpc-endpoint" }
}
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PHASE 10 — CloudWatch Alarms + SNS

# modules/monitoring/main.tf

resource "aws_sns_topic" "alerts" {
  name              = "production-alerts"
  kms_master_key_id = var.kms_key_id
}

resource "aws_sns_topic_subscription" "email" {
  topic_arn = aws_sns_topic.alerts.arn
  protocol  = "email"
  endpoint  = var.alert_email
}

# RDS CPU Alarm
resource "aws_cloudwatch_metric_alarm" "rds_cpu" {
  alarm_name          = "rds-high-cpu"
  comparison_operator = "GreaterThanThreshold"
  evaluation_periods  = 2
  metric_name         = "CPUUtilization"
  namespace           = "AWS/RDS"
  period              = 120
  statistic           = "Average"
  threshold           = 80
  alarm_description   = "RDS CPU above 80%"
  alarm_actions       = [aws_sns_topic.alerts.arn]
  dimensions          = { DBInstanceIdentifier = var.rds_identifier }
}

# EKS Node CPU Alarm
resource "aws_cloudwatch_metric_alarm" "eks_cpu" {
  alarm_name          = "eks-node-high-cpu"
  comparison_operator = "GreaterThanThreshold"
  evaluation_periods  = 2
  metric_name         = "node_cpu_utilization"
  namespace           = "ContainerInsights"
  period              = 60
  statistic           = "Average"
  threshold           = 80
  alarm_description   = "EKS node CPU above 80%"
  alarm_actions       = [aws_sns_topic.alerts.arn]
  dimensions          = { ClusterName = var.eks_cluster_name }
}
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PHASE 11 — Security (GuardDuty, Security Hub, CloudTrail)

# modules/security/main.tf

# GuardDuty
resource "aws_guardduty_detector" "main" {
  enable = true
  datasources {
    s3_logs            { enable = true }
    kubernetes { audit_logs { enable = true } }
    malware_protection { scan_ec2_instance_with_findings { ebs_volumes { enable = true } } }
  }
}

# Security Hub
resource "aws_securityhub_account" "main" {}

resource "aws_securityhub_standards_subscription" "cis" {
  depends_on    = [aws_securityhub_account.main]
  standards_arn = "arn:aws:securityhub:eu-central-1::standards/cis-aws-foundations-benchmark/v/1.4.0"
}

# CloudTrail
resource "aws_cloudtrail" "main" {
  name                          = "production-trail"
  s3_bucket_name                = aws_s3_bucket.cloudtrail.id
  include_global_service_events = true
  is_multi_region_trail         = true
  enable_log_file_validation    = true
  kms_key_id                    = var.kms_key_arn

  event_selector {
    read_write_type           = "All"
    include_management_events = true
    data_resource {
      type   = "AWS::S3::Object"
      values = ["arn:aws:s3:::"]
    }
  }
}

resource "aws_s3_bucket" "cloudtrail" {
  bucket        = "cloudtrail-logs-${var.account_id}"
  force_destroy = false
}
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PHASE 12 — AWS Amplify Frontend

# modules/amplify/main.tf

resource "aws_amplify_app" "frontend" {
  name       = "production-frontend"
  repository = var.github_repo_url

  build_spec = <<-EOT
    version: 1
    frontend:
      phases:
        preBuild:
          commands:
            - npm install
        build:
          commands:
            - npm run build
      artifacts:
        baseDirectory: build
        files:
          - '**/*'
      cache:
        paths:
          - node_modules/**/*
  EOT

  environment_variables = {
    REACT_APP_API_URL = var.alb_dns_name
  }
}

resource "aws_amplify_branch" "main" {
  app_id      = aws_amplify_app.frontend.id
  branch_name = "main"
  stage       = "PRODUCTION"
  framework   = "React"
}
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PHASE 13 — Deploy Everything

# 1. Init and apply Terraform
terraform init
terraform plan -out=tfplan
terraform apply tfplan

# 2. Connect to EKS
aws eks update-kubeconfig --region eu-central-1 --name production-eks

# 3. Deploy Kubernetes manifests
kubectl apply -f k8s/secrets.yaml
kubectl apply -f k8s/api-service.yaml
kubectl apply -f k8s/auth-service.yaml
kubectl apply -f k8s/document-service.yaml
kubectl apply -f k8s/notification-service.yaml
kubectl apply -f k8s/ingress.yaml

# 4. Verify everything
kubectl get pods -n production
kubectl get ingress -n production
kubectl get svc -n production
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Project Folder Structure

.
├── backend-setup/
│   └── main.tf
├── modules/
│   ├── kms/
│   ├── vpc/
│   ├── rds/
│   ├── secrets/
│   ├── ecr/
│   ├── eks/
│   ├── s3/
│   ├── monitoring/
│   ├── security/
│   └── amplify/
├── k8s/
│   ├── secrets.yaml
│   ├── api-service.yaml
│   ├── auth-service.yaml
│   ├── document-service.yaml
│   ├── notification-service.yaml
│   └── ingress.yaml
├── main.tf
├── variables.tf
├── outputs.tf
└── backend.tf
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Estimated Cost (eu-central-1)

Service Cost/Month
EKS Cluster ~$73
EC2 Nodes (2x t3.medium) ~$60
RDS PostgreSQL Multi-AZ (t3.medium) ~$90
NAT Gateway ~$35
ALB ~$20
S3 + CloudTrail ~$5
Total ~$283/month

Tip: Use spot instances for EKS nodes in dev/staging to cut costs by 70%.

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