ad4469dc-7beb-4b7f-90b1-7de220c49931/docs/02_first_ec2.md

2) Your First Terraform Apply: EC2 (20 min)

In this section, you will create your first Terraform project and use it to launch an Amazon EC2 instance in your AWS account. This is the "Hello World" of Terraform on AWS.

Step 1: Create a new project directory

mkdir -p ~/terraform-ec2-lab && cd ~/terraform-ec2-lab

• mkdir -p ~/terraform-ec2-lab → Creates a folder called terraform-ec2-lab in your home directory. The -p option ensures the folder is created even if parent directories don’t exist.
• cd ~/terraform-ec2-lab → Moves into this new folder so you can keep your Terraform files organized.

This directory will hold all the configuration files for this project.

Step 2: Create the main configuration file

Create a new file named main.tf and paste the following code:

provider "aws" {
  region = "ap-south-1"
}

resource "aws_instance" "lab_instance" {
  ami           = "ami-0e6329e222e662a52" # Amazon Linux 2 (Mumbai)
  instance_type = "t2.micro"

  tags = {
    Name = "Terraform-Lab-Instance"
  }
}

Explanation of the code

• provider "aws"
  Tells Terraform to use the AWS provider. The region is set to ap-south-1 (Mumbai). This determines where your resources will be created.

• resource "aws_instance" "lab_instance"
  Declares that we want to create an EC2 instance resource in AWS.

  • ami: The Amazon Machine Image (AMI) ID that defines the OS. Here we use Amazon Linux 2 in the Mumbai region.
  • instance_type: Specifies the hardware size of the instance. t2.micro is eligible for AWS Free Tier.
  • tags: Adds a tag so the instance will appear in AWS Console with the name Terraform-Lab-Instance.

Step 3: Initialize Terraform

terraform init

• Downloads the AWS provider plugin.
• Prepares your working directory for use with Terraform.

Step 4: Preview the changes

terraform plan

• Shows the actions Terraform will take without actually applying them.
• Useful for double-checking that the configuration does what you expect.

Step 5: Apply the configuration

terraform apply -auto-approve

• Creates the EC2 instance in AWS according to your configuration.
• The -auto-approve flag skips the interactive “yes/no” confirmation step. (Normally Terraform asks before making changes.)

Step 6: Verify in AWS Console

1. Log in to the AWS Management Console.
2. Navigate to EC2 → Instances.
3. You should see a running instance named Terraform-Lab-Instance.
4. Confirm its details:
   • Instance type: t2.micro
   • AMI: Amazon Linux 2
   • Region: ap-south-1 (Mumbai)

Wrap-Up

Congratulations! 🎉 You just:

• Wrote your first Terraform configuration.
• Initialized Terraform.
• Planned and applied infrastructure changes.
• Verified the deployed EC2 instance in AWS.

This is the foundation of Infrastructure as Code: describe what you want → apply → verify.