DevOps Challenger

"Mastering Terraform: A Comprehensive Guide to Infrastructure as Code"

Sibananda Pradhan's photo
Sibananda Pradhan
·

6 min read

Table of contents

Your Ultimate Guide to Installing, Using, and Excelling with Terraform Across Platforms"

What is Terraform?

  • Definition: Terraform is an open-source Infrastructure as Code (IaC) tool by HashiCorp.

  • Purpose: Automates the provisioning and management of cloud and on-premises infrastructure.

  • Key Features:

    • Uses HashiCorp Configuration Language (HCL).

    • Works with multiple cloud providers (AWS, Azure, GCP, etc.).

    • Supports hybrid and multi-cloud environments.

Why Use Terraform?

  • Cross-Platform: Works seamlessly across various cloud providers.

  • Declarative: Defines the desired infrastructure state and automates provisioning.

  • Version Control: Easily track changes to your infrastructure configurations.

  • Reusable Code: Utilize modules for better organization and scalability.

  • Cost-Efficient: Reduces manual work and minimizes human errors.

How to Use Terraform?

  1. Write: Define infrastructure in .tf configuration files.

  2. Plan: Run terraform plan to preview changes without applying them.

  3. Apply: Execute terraform apply to create or modify resources.

Basic Terraform Workflow

  • Step 1: Install Terraform.

  • Step 2: Create a working directory for your project.

  • Step 3: Write a configuration file (e.g., main.tf).

        provider "aws" {
    region = "us-east-1"
  }

  resource "aws_instance" "example" {
    ami           = "ami-0c55b159cbfafe1f0"
    instance_type = "t2.micro"
  }

  • Step 4: Initialize Terraform in the directory:

      terraform init

  • Step 5: Plan and apply:

    • Preview changes: terraform plan

    • Apply changes: terraform apply

    • Destroy resources: terraform destroy

How to Install Terraform?

Windows:

  1. Download the .zip file from Terraform Downloads.

  2. Extract the file to a folder (e.g., C:\Terraform).

  3. Add the folder path to the system's PATH variable:

  4. Verify the installation:

           terraform -v

Linux:

  1. Install Terraform using the package manager:

     curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo gpg --dearmor -o /usr/share/keyrings/hashicorp-archive-keyring.gpg
 echo "deb [signed-by=/usr/share/keyrings/hashicorp-archive-keyring.gpg] https://apt.releases.hashicorp.com $(lsb_release -cs) main" | sudo tee /etc/apt/sources.list.d/hashicorp.list
 sudo apt update && sudo apt install terraform

  2. Verify the installation:

       terraform -v

macOS:

  1. Install Terraform using Homebrew:

     brew tap hashicorp/tap
 brew install hashicorp/tap/terraform

  2. Verify the installation:

      terraform -v

How to Set Up Terraform?

  • Step 1: Create a directory for your project (e.g., my-terraform-project).

  • Step 2: Initialize Terraform in the directory:

       terraform init

  • Step 3: Write infrastructure definitions in .tf files

  •         main.tf

  • Step 4: Use backend configuration (optional):

    • Store state files in aws,S3, Azure Blob, etc., for collaboration.

  • Step 5: Use Terraform commands:

    • terraform plan: Preview changes.

    • terraform apply: Deploy resources.

    • terraform destroy: Remove infrastructure.

  1. How to Create EC2 Instances with Terraform with twist:-

    Terraform is an excellent tool for managing cloud infrastructure as code. I will guide you through the process of creating an EC2 instance on AWS using Terraform. Whether you’re a beginner or experienced, this easy-to-follow guide will help you get your EC2 instance up and running quickly.

    Prerequisites

    Before starting with Terraform, make sure you have the following:

    • AWS Account: You need an AWS account to create EC2 instances and other resources. If you don't have one, sign up here.

    • Create a New IAM User

      1. In the IAM Dashboard, click on the Users option in the left sidebar.

      2. Click on the Add user button to start the process of creating a new IAM user.

        User name: Enter a unique name for the user (e.g., john_doe).

        • Access type: Choose whether the user will have Programmatic access (access to AWS via API, CLI, etc.) or AWS Management Console access (access to the web console). You can also select both option.

          Programmatic access: Provides an Access key ID and Secret access key.

          Console access: Provides a username and password for the AWS Management Console.

Step-by-Step Guide to Create EC2 Instances with Terraform

Step 1: Configure AWS CLI

To interact with AWS through Terraform, you need to configure your AWS credentials. The easiest way is to use the AWS CLI.

  1. Install AWS CLI (if you haven't already).

  2. Check version of AWS CLI:

     aws --version

  3. Run the following command to configure your credentials:

      aws configure

  4. You’ll be prompted to enter your AWS Access Key, Secret Key, region, and output format. These keys can be found in the AWS IAM user

    Set the following environment variables in your terminal:

    ```bash

export AWS_ACCESS_KEY_ID="your-access-key-id" export AWS_SECRET_ACCESS_KEY="your-secret-access-key" export AWS_DEFAULT_REGION="us-east-1"



    ---

    #### **Step 2: Create a Directory for Your Terraform Configuration**

    Create a directory on your local machine to store the Terraform configuration files.

    ```bash
     mkdir terraform-ec2
     cd terraform-ec2

Step 3: Write Your Terraform Configuration

In the new directory, create a .tf file (e.g., main.tf) where you’ll define the resources for your EC2 instance.

    vim main.tf

Here’s an example of what the main.tf file could look like:

    provider "aws" {
      region = "us-east-1"  # Choose your AWS region
    }

    resource "aws_instance" "my_ec2" {
      ami           = "ami-0c55b159cbfafe1f0"  # Replace with a valid AMI ID
      instance_type = "t2.micro"  # You can change the instance type based on your needs

      tags = {
        Name = "MyEC2Instance"
      }
    }

  • provider: Defines the AWS provider and the region.

  • aws_instance: Defines to create an EC2 instance. You specify the AMI ID (Amazon Machine Image) and instance type.

Make sure to replace the AMI ID with one that’s valid for your region. You can find AMI IDs on the AWS Console.

Step 4: Initialize Terraform

Run the following command in your project directory to initialize Terraform:

    terraform init

This command downloads the necessary provider plugins and prepares Terraform for use.

Step 5: Plan the Deployment

To preview what Terraform will do, run the terraform plan command:

     terraform plan

This will show you a detailed preview of the actions Terraform will take, such as creating an EC2 instance.

Step 6: Apply the Configuration

Once you’re satisfied with the plan, apply the configuration to create the EC2 instance:

     terraform apply

Terraform will ask you to confirm by typing yes. After confirmation, it will create the EC2 instance based on the configuration.

Step 7: Verify the EC2 Instance

Once Terraform completes the provisioning process, you can verify that the EC2 instance is running by checking the AWS Console.

  1. Go to the EC2 Dashboard.

  2. Look for an instance with the tag Name = MyEC2Instance.

Step 8: Clean Up (Destroying the EC2 Instance)

If you no longer need the EC2 instance, you can delete it by running:

     terraform destroy

This command will destroy the EC2 instance and any other resources that were created.

-To delete only the my_ec2 instance:

    terraform destroy -target=aws_instance.my_ec2

Important Notes

  • This command only deletes the EC2 instance itself. Other resources (like VPCs, security groups, etc.) will not be affected unless explicitly targeted.

  • Ensure that the resource name in the -target matches exactly with your configuration file.

This gives you the flexibility to delete specific resources while keeping others intact.

Conclusion

Using Terraform not only saves time but also ensures consistency and scalability in your infrastructure. By leveraging Infrastructure as Code (IaC), you reduce manual errors and create a repeatable process for deploying resources.

Start small, practice, and gradually automate more aspects of your cloud architecture.

Happy Automating with Terraform! 🚀

#90daysofdevopsTrainWithShubham Abhishek Veeramalla