Terraform Day 01: Getting Started with Infrastructure as Code

Intro:
Today I started my Terraform with AWS learning journey. Before diving into AWS, I wanted to get clear on the fundamentals — what Terraform actually is and how to set it up. After that, I moved straight into deploying my first Nginx server on AWS using Terraform.

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🔹 What is Terraform?

Terraform is an open-source Infrastructure as Code (IaC) tool created by HashiCorp. It allows you to define your infrastructure (servers, networks, storage, etc.) in code and then automatically provision it.

• Instead of manually creating resources in the AWS console, you write code.

• This code is reusable, shareable, and version-controlled.

• Terraform supports multiple cloud providers (AWS, Azure, GCP, etc.), making it cloud-agnostic.

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🔹 Installing Terraform

Steps I followed to install Terraform on my machine:

1. Download Terraform binary from terraform.io

2. Add it to system PATH

3. Verify installation with:

    terraform -version
   

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🔹 First Hands-On: Deploying Nginx on AWS

After installation, I configured AWS credentials and created my first Terraform file (main.tf) to deploy an EC2 instance with Nginx installed.

Code snippet:

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

resource "aws_instance" "nginx" {
  ami           = "ami-123456"  # Ubuntu AMI
  instance_type = "t2.micro"

  user_data = <<-EOF
              #!/bin/bash
              sudo apt update -y
              sudo apt install nginx -y
              EOF

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

Commands used:

terraform init  
terraform plan  
terraform apply

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🔹 Understanding Terraform Commands

When working with Terraform, you usually follow a workflow of Init → Plan → Apply. Here’s what each command does:

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1️⃣ terraform init

• This command initializes your working directory for Terraform.

• It downloads the required provider plugins (like AWS, Azure, GCP) so Terraform can communicate with the chosen cloud.

• It also sets up the .terraform folder in your project where dependencies are stored.

👉 Think of it as “setting up the environment before building anything.”
If you don’t run init, Terraform won’t know how to talk to AWS.

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2️⃣ terraform plan

• This command shows you what Terraform will do before making any actual changes.

• It compares your code (.tf files) with the current infrastructure state.

• The output will clearly list:

  • Resources to be created

  • Resources to be modified

  • Resources to be destroyed

👉 Think of it as a dry run or preview mode.
This is super useful in real-world projects because you want to double-check changes before applying them on production.

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3️⃣ terraform apply

• This command executes the plan and actually provisions (creates/updates/destroys) resources on AWS.

• Terraform will first ask for confirmation:

    Do you want to perform these actions?
      Only 'yes' will be accepted to approve.
  

• After typing yes, Terraform will call AWS APIs and provision the resources as described in your code.

👉 Think of it as the final step where your infrastructure comes alive.

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Quick Summary in One Line:

• init → Get ready

• plan → Show me what will happen

• apply → Make it happen 🚀

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🔹 Reflection

Day 01 taught me two important things:

• Terraform makes AWS provisioning much faster and repeatable

• Even a simple Nginx server shows the power of IaC

👉 Full code available on my GitHub

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