How to Launch an EC2 Instance using Terraform

Introduction

Terraform is an Infrastructure as Code (IaC) tool that helps you automate AWS resource deployment. In this tutorial, you'll learn how to use Terraform to launch an EC2 instance on AWS.

Prerequisites

Before starting, ensure you have:

• An AWS account

• AWS CLI installed and configured (aws configure)

• Terraform installed (Download Terraform)

Step 1: Create a Working Directory

Create a new folder for your Terraform project and navigate into it:

mkdir terraform-ec2 && cd terraform-ec2

Step 2: Write the Terraform Configuration File

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

provider "aws" {
  region = "us-east-1" # Change to your preferred region
}

resource "aws_security_group" "terraform_sg" {
  name_prefix = "terraform-sg"
  description = "Allow SSH and HTTP access"

  ingress {
    from_port   = 22
    to_port     = 22
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"] # Restrict this in a real-world scenario
  }

  ingress {
    from_port   = 80
    to_port     = 80
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }
}

resource "aws_instance" "example" {
  ami           = "ami-0c55b159cbfafe1f0"  # Replace with a valid AMI ID
  instance_type = "t2.micro"
  security_groups = [aws_security_group.terraform_sg.name]

  tags = {
    Name = "Terraform-EC2"
  }
}

Step 3: Initialize Terraform

Run the following command to initialize the Terraform project:

terraform init

This will download the necessary provider plugins.

Step 4: Preview the Changes

Check what resources Terraform will create:

terraform plan

Review the output to ensure everything looks correct.

Step 5: Deploy the EC2 Instance

Run the following command to create the EC2 instance:

terraform apply -auto-approve

Terraform will provision the EC2 instance, and you will see the instance ID in the output.

Step 6: Connect to the Instance via SSH

If you have a key pair associated with your AWS account, you can SSH into the instance using:

ssh -i /path/to/your-key.pem ec2-user@your-instance-public-ip

You can find the public IP using:

aws ec2 describe-instances --query "Reservations[*].Instances[*].PublicIpAddress" --output text

Step 7: Verify the Instance

You can check if the EC2 instance is running using AWS CLI:

aws ec2 describe-instances --query "Reservations[*].Instances[*].InstanceId" --output text

Alternatively, go to the AWS Management Console and verify the instance in the EC2 Dashboard.

Step 8: Destroy the Instance (Optional)

If you want to delete the EC2 instance and free up resources, run:

terraform destroy -auto-approve

Conclusion

Congratulations! You have successfully launched an EC2 instance using Terraform. This tutorial covered:

• Writing a Terraform configuration file

• Creating a security group to allow SSH and HTTP access

• Initializing Terraform

• Applying Terraform to deploy an EC2 instance

• Connecting to the instance via SSH

• Verifying and destroying the instance

For more Terraform tutorials, stay tuned to our blog!