Terraform AWS EC2 with Workspaces

This repository demonstrates how to use Terraform to manage AWS EC2 instances across multiple environments (dev, stage, and prod) with Terraform workspaces. Workspaces enable environment-specific configurations, such as instance types, while keeping the infrastructure code reusable and organized.

Repository Structure

.
├── modules/
│   └── ec2_instance/
│       └── main.tf
├── main.tf
├── terraform.tfvars
└── README.md

• modules/ec2_instance/main.tf: Defines the reusable EC2 instance module.
• main.tf: Configures the root module and integrates the EC2 module with workspace-specific settings.
• terraform.tfvars: Specifies the AMI ID for the EC2 instances.

Overview

This project uses Terraform workspaces to manage separate EC2 instances for different environments, each with its own instance type:

• dev: t2.micro
• stage: t2.small
• prod: t2.nano

The AMI ID is shared across all environments and defined in terraform.tfvars. The AWS region is set to ap-south-1.

Prerequisites

• Terraform installed on your system.
• AWS CLI configured with permissions to create EC2 instances.
• AWS credentials set up (e.g., via environment variables, shared credentials file, or IAM roles).

How to Use This Repository

1. Clone the Repository

git clone https://github.com/<your-username>/terraform-aws-ec2-workspaces.git
cd terraform-aws-ec2-workspaces

2. Initialize Terraform

Initialize the Terraform working directory to download provider plugins:

terraform init

3. Manage Workspaces

Terraform workspaces allow you to manage separate instances of your infrastructure. Use them to switch between environments.

• List available workspaces:

terraform workspace list

• Create a new workspace (e.g., dev, stage, or prod):

terraform workspace new dev

• Switch to an existing workspace:

terraform workspace select dev

The instance type is automatically set based on the active workspace.

4. Apply the Configuration

Provision the EC2 instance for the selected workspace:

terraform apply

Review the plan and type yes to confirm.

5. Verify Resources

• Log in to the AWS Management Console.
• Go to the EC2 dashboard and confirm the instance type matches the selected workspace:
  • dev: t2.micro
  • stage: t2.small
  • prod: t2.nano

6. Clean Up

Destroy resources to avoid unnecessary costs:

terraform destroy

Confirm with yes. Ensure the correct workspace is selected, as each has its own state.

Configuration Details

Module: modules/ec2_instance/main.tf

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

variable "ami" {
  description = "This is AMI for the instance"
}

variable "instance_type" {
  description = "This is the instance type, for example: t2.micro"
}

resource "aws_instance" "example" {
  ami           = var.ami
  instance_type = var.instance_type
}

• Provider: AWS, fixed to ap-south-1.
• Variables:
  • ami: The AMI ID for the instance.
  • instance_type: The EC2 instance type.
• Resource: Creates an EC2 instance with the specified AMI and instance type.

Root: main.tf

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

variable "ami" {
  description = "value"
}

variable "instance_type" {
  description = "value"
  type        = map(string)
  default = {
    "dev"   = "t2.micro"
    "stage" = "t2.small"
    "prod"  = "t2.nano"
  }
}

module "ec2_instance" {
  source        = "./modules/ec2_instance"
  ami           = var.ami
  instance_type = lookup(var.instance_type, terraform.workspace, "t2.micro")
}

• Provider: AWS, set to ap-south-1.
• Variables:
  • ami: Defined in terraform.tfvars.
  • instance_type: A map linking workspaces to instance types.
• Module: Calls the ec2_instance module, dynamically selecting the instance type based on the workspace.

Variables: terraform.tfvars

ami = "ami-053b12d3152c0cc71"

• Specifies the AMI ID for the ap-south-1 region. Verify its validity for your use case.

Key Features

• Workspaces: Manage dev, stage, and prod environments with separate states.
• Modularity: Reusable EC2 instance logic in a module.
• Dynamic Configuration: Instance types adjust automatically based on the workspace.

Example Workspaces

Workspace	Instance Type
dev	t2.micro
stage	t2.small
prod	t2.nano

Note: t2.nano for prod is for demonstration. Production typically requires larger instances.

Additional Notes

• Region: Fixed to ap-south-1 in both the root and module configurations.
• AMI: Hardcoded in terraform.tfvars. For flexibility, consider using a data source to fetch the latest AMI.
• State Management: Each workspace has its own state file. Be mindful when switching to manage the correct resources.