Terraform VPC and EKS Infrastructure

This repository provisions a complete AWS infrastructure using Terraform, including a Virtual Private Cloud (VPC) and an Amazon EKS cluster with a managed node group.

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Architecture Overview

The infrastructure includes:

VPC

• Custom VPC
• Public and private subnets across multiple Availability Zones
• Internet Gateway
• NAT Gateway with Elastic IP
• Public and private route tables and associations

EKS

• EKS cluster
• IAM role for the EKS control plane
• Managed node group
• Configurable Kubernetes version and autoscaling settings

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Prerequisites

• Terraform >= 1.5
• AWS CLI installed and configured
• AWS credentials with sufficient permissions
• An AWS account

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Project Structure

.
├── main.tf
├── provider.tf
├── variables.tf
├── terraform.tfvars
├── vpc/
│   ├── main.tf
│   ├── variables.tf
│   └── outputs.tf
└── eks/
    ├── main.tf
    └── variables.tf

Example terraform.auto.tfvars file

vpc_name             = "my-vpc"
cidr_block           = "10.0.0.0/16"

public_subnet_cidrs  = ["10.0.1.0/24", "10.0.2.0/24"]
private_subnet_cidrs = ["10.0.3.0/24", "10.0.4.0/24"]

availability_zones   = ["us-west-2a", "us-west-2b"]

igw                  = "my-igw"
eip                  = "my-elastic-ip"
nat_gateway          = "my-nat-gateway"

public_route_cidr    = "0.0.0.0/0"
private_route_cidr   = "0.0.0.0/0"

cluster_name         = "my-eks-cluster"
cluster_role_name    = "ClusterIamrole"
eks_version          = "1.31"

node_group_name      = "eks-node-group"
node_role_name       = "NodeIamrole"
instance_types       = ["t2.large"]

desired_size         = 1
min_size             = 1
max_size             = 3

Input Variables

Variable	Description
vpc_name	Name of the VPC
cidr_block	CIDR block for the VPC
public_subnet_cidrs	CIDR blocks for public subnets
private_subnet_cidrs	CIDR blocks for private subnets
availability_zones	Availability Zones for subnets
igw	Internet Gateway name
eip	Elastic IP for NAT Gateway
nat_gateway	NAT Gateway name
public_route_cidr	Public route CIDR
private_route_cidr	Private route CIDR
cluster_name	EKS cluster name
cluster_role_name	IAM role name for EKS cluster
eks_version	Kubernetes version
node_group_name	EKS node group name
node_role_name	IAM role name for worker nodes
instance_types	EC2 instance types for worker nodes
desired_size	Desired number of nodes
min_size	Minimum node count
max_size	Maximum node count

Root main.tf

The root main.tf wires the modules together:

module "vpc" {
  source               = "./vpc"
  vpc_name             = var.vpc_name
  cidr_block           = var.cidr_block
  availability_zones   = var.availability_zones
  public_subnet_cidrs  = var.public_subnet_cidrs
  private_subnet_cidrs = var.private_subnet_cidrs
  igw                  = var.igw
  public_route_cidr    = var.public_route_cidr
  private_route_cidr   = var.private_route_cidr
  eip                  = var.eip
  nat_gateway          = var.nat_gateway
}

module "eks" {
  source            = "./eks"
  vpc_id            = module.vpc.vpc_id
  subnet_ids        = module.vpc.private_subnet_ids
  cluster_name      = var.cluster_name
  eks_version       = var.eks_version
  node_role_name    = var.node_role_name
  cluster_role_name = var.cluster_role_name
  node_group_name   = var.node_group_name
  instance_types    = var.instance_types
  desired_size      = var.desired_size
  max_size          = var.max_size
  min_size          = var.min_size

  depends_on        = [module.vpc]
}