README: Creating a VPC Using Terraform

This README provides step-by-step instructions for creating a Virtual Private Cloud (VPC) using Terraform. Please follow the steps below to set up your AWS VPC infrastructure.

Prerequisites

Before you begin, ensure that you have the following prerequisites in place:

1. Terraform installed on your local machine.
2. AWS credentials configured. You can set up AWS CLI or configure the ~/.aws/credentials file.

Getting Started

Step 1: Clone or Create Your Terraform Project

You can either clone an existing Terraform project or create a new one. In this README, we'll assume you're starting from scratch.

Step 2: Create the Terraform Configuration Files

providers.tf

Create a providers.tf file to configure the AWS provider. Ensure you have the AWS provider installed.

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 5.0"
    }
  }
}

# Configure the AWS Provider
provider "aws" {
  region = "ap-south-1" # Specify your desired AWS region
}

main.tf

Create a main.tf file with the Terraform code to create a VPC, public and private subnets, internet gateway, and route tables.

# Step 1: Create a VPC
resource "aws_vpc" "myvpc" {
  cidr_block = "10.0.0.0/16"
  tags = {
    Name = "Terraform VPC"
  }
}

# Step 2: Create a Public Subnet
resource "aws_subnet" "PublicSubnet" {
  vpc_id     = aws_vpc.myvpc.id
  cidr_block = "10.0.1.0/24"
  tags = {
    Name = "Public Subnet"
  }
}

# Step 3: Create a Private Subnet
resource "aws_subnet" "PrivateSubnet" {
  vpc_id     = aws_vpc.myvpc.id
  cidr_block = "10.0.2.0/24"
  tags = {
    Name = "Private Subnet"
  }
}

# Step 4: Create Internet Gateway
resource "aws_internet_gateway" "igw" {
  vpc_id = aws_vpc.myvpc.id
}

# Step 5: Create a Route Table for the Public Subnet
resource "aws_route_table" "PublicRT" {
  vpc_id = aws_vpc.myvpc.id

  route {
    cidr_block = "0.0.0.0/0"
    gateway_id = aws_internet_gateway.igw.id
  }
}

# Step 6: Associate the Route Table with the Public Subnet
resource "aws_route_table_association" "PublicRTassociation" {
  subnet_id      = aws_subnet.PrivateSubnet.id
  route_table_id = aws_route_table.PublicRT.id
}

Step 3: Running Terraform Commands

Open your terminal and navigate to the directory containing your Terraform project. Follow these commands to manage your infrastructure:

Initialize the Project

Run the following command to initialize your Terraform project. This command downloads the AWS provider and sets up the working directory.

terraform init

Validate Your Configuration

Check if your Terraform configuration is syntactically correct and internally consistent.

terraform validate

Plan Your Changes

Generate an execution plan to understand what Terraform will do before making any changes to your infrastructure.

terraform plan

Apply Changes

Apply the changes defined in your Terraform configuration to create the VPC and related resources.

terraform apply

Terraform will prompt you to confirm the planned changes. Type "yes" to proceed.

Destroy Resources (Optional)

If you want to destroy the infrastructure created with Terraform, use the following command:

terraform destroy

Terraform will prompt you to confirm the destruction. Type "yes" to proceed.

Conclusion

You've successfully created a VPC and related resources using Terraform. This README covers the essential steps to set up your infrastructure, validate, plan, apply changes, and optionally destroy resources. Happy Terraforming!