Terraform

Terraform is an infrastructure as code tool that lets you build, change, and version cloud and on-prem resources safely and efficiently.

Working :

HashiCorp and the Terraform community have already written thousands of providers to manage many different types of resources and services.

The core Terraform workflow consists of three stages:

• Write: You define resources, which may be across multiple cloud providers and services. For example, you might create a configuration to deploy an application on virtual machines in a Virtual Private Cloud (VPC) network with security groups and a load balancer.

• Plan: Terraform creates an execution plan describing the infrastructure it will create, update, or destroy based on the existing infrastructure and your configuration.

• Apply: On approval, Terraform performs the proposed operations in the correct order, respecting any resource dependencies. For example, if you update the properties of a VPC and change the number of virtual machines in that VPC, Terraform will recreate the VPC before scaling the virtual machines.

Download Terraform for Windows

ON Web Browser https://developer.hashicorp.com/terraform/install

Under Windows, select :

Architecture: 64-bit

It will download a .zip file (example: terraform_1.9.8_windows_amd64.zip).

Extract the ZIP File

Right-click on the downloaded ZIP → Extract All

Move this terraform.exe to a permanent location

for example :

C:\Terraform

Add Terraform to System PATH

1. Press Windows + R, type sysdm.cpl → press Enter

2. Go to Advanced → click Environment Variables

3. Under System Variables, find Path, select it → click Edit

4. Click New → add the path where terraform.exe is located

5. Click OK

6. Verify Installation

7. Open Command Prompt

   terraform -version
   
   # You see
   Terraform v1.13.4
   on windows_386
   

Why the .tf extension itself is needed in Terraform ?

The .tf extension tells Terraform that the file contains Terraform configuration code written in HCL (HashiCorp Configuration Language) .
Without the .tf extension, Terraform won’t recognize the file as part of the configuration it should read and execute .

Create main.tf

terraform {
  required_providers {
    aws = {
      source = "hashicorp/aws"
      version = "6.18.0"
    }
  }
}

provider "aws" {
  region = "ap-south-1"
  ami = "ami-00af95fa354fdb788"
  instance_type = "t2.micro"
  tags = {
    Name = "terraform machine"
  }
}

Initialize the directory (terraform init)

In the folder where main.tf lives, run :

terraform init

# you see 
Initializing the backend...
Initializing provider plugins...
- Reusing previous version of hashicorp/aws from the dependency lock file
- Using previously-installed hashicorp/aws v6.18.0

Terraform has been successfully initialized!

You may now begin working with Terraform. Try running "terraform plan" to see
any changes that are required for your infrastructure. All Terraform commands
should now work.

If you ever set or change modules or backend configuration for Terraform,
rerun this command to reinitialize your working directory. If you forget, other
commands will detect it and r                                emind you to do so if necessary.

What terraform init does:

• Downloads provider plugins (here, hashicorp/random) into the local plugin cache.

• Sets up the backend (by default that's the local file terraform.tfstate).

• Prepares the working directory for plan/apply.

Using Terraform with Git Bash on Windows is a common setup.

Install and configure Git on Windows

Open the official Git website : https://git-scm.com/install/

Click Windows → download will start → Run the installer

1. Open Git Bash → Configure Git

2.     git config --global user.name "Your Name"
       git config --global user.email "your-email@example.com"
       git config --list
   

3.     terraform -v   # If you see a version output, installation is successful.
   

Create a Terraform Working Directory

mkdir /terraform/project1

cd  /terraform/project1

Create the main file :

main.tf

Initialize Terraform :

terraform init

Write a code in main.tf

vi main.tf

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 6.0"
    }
  }
}

provider "aws" {
  region     = "ap-south-1"
  access_key = "**************"
  secret_key = "**************"
}
resource "aws_instance" "e1" {
  ami           = "ami-01760eea5c574eb86"
  instance_type = "t2.micro"

  tags = {
    Name = "example-instance1"
  }
}

See What Terraform Will Create

terraform plan

Apply Changes

terraform apply

Destroy Resources

terraform destroy

VS Code is the best way to start working with Terraform because it gives you syntax highlighting, autocompletion, and error checking .

Install VS Code - https://code.visualstudio.com/docs/?dv=win64user

Install HashiCorp Terraform Extension in VS Code

• Go to Extensions .

• Search for “HashiCorp Terraform”

• Click Install

• This extension provides:

  • Syntax highlighting for .tf files

  • IntelliSense (auto-completion)

  • Terraform CLI integration

  • Validation & formatting

Configure Terraform in VS Code

Create a new folder

File → Open Folder → terraform-project

Create a new file : Set environment variables

.env

setx AWS_ACCESS_KEY_ID AKIAIOSFODNN7EXAMPLE
setx AWS_SECRET_ACCESS_KEY wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY
setx AWS_REGION us-west-2

open in integrated terminal

# Git bash 

source .env

The command source .env is used in a Unix-like shell environment to execute the contents of a file, typically named .env, within the current shell session. This means that any variables defined in the .env file will be loaded as environment variables and become accessible to subsequent commands executed in that same shell.

Create a new folder

New folder → folder name

Inside folder Create a new file for code writing

New file → file name

Select file and write a code in text file

# Terraform settings and provider requirements
terraform {
  required_providers {
    aws = {
      source = "hashicorp/aws"
      version = "6.20.0"
    }
  }
}

# how and where to connect to AWS
provider "aws" {
  region = "ap-south-1"
}

# creates an AWS EC2 instance
 resource "aws_instance" "e1" {
  ami           = "ami-01760eea5c574eb86"
  instance_type = "t2.micro"

  tags = {
    Name = "example-instance1"
  }
} 

After that

open in integrated terminal → Git bash

Path of .tf file

source .env

terraform init

terrafrom vaildate 

terrafrom plan 

terraform apply 

terraform destroy 

Terraform Registry :

The Terraform Registry is an official website by HashiCorp that provides a central catalog of providers, modules, and examples that you can use in your Terraform projects .