Infrastructure as Code Made Simple: Terraform on AWS - Part 1

What is Terraform?

Terraform is an open-source Infrastructure as Code (IaC) tool by HashiCorp that allows you to define, provision, and manage infrastructure using declarative configuration files. Instead of manually creating resources, Terraform automates the process, ensuring consistency and scalability.

• Overview
• What is Infrastructure as Code?

AWS Setup

Before writing Terraform configurations, we need AWS access and proper authentication setup. This section covers everything you need to get started with Terraform on AWS, from account setup to credential configuration.

• Create AWS Account
• IAM User Creation
• AWS CLI configured on your local system

First Terraform Configuration

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

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

• Basic Configuration Structure
  • Configuration Files
  • Provider Block
  • Resource Block

Terraform Core Commands

The most used Terraform commands for managing your infrastructure. This section covers all essential commands from initialization to resource management, helping you understand the complete Terraform workflow.

terraform init
terraform validate
terraform plan
terraform apply

🔗 Terraform CLI Commands

State Management

Terraform stores resource metadata in a state file (terraform.tfstate). This helps Terraform track real-world resources.

• Local state – stored in your project folder
• Remote state – stored in AWS S3 or Terraform Cloud for collaboration

🔗 Terraform State Docs

Variables & Outputs

Variables make Terraform configurations reusable and dynamic. Instead of hardcoding values (like region, instance type, or database name) in a file like terraform.tfvars.

• Input Variables
• Outputs Values
• Local Value

Input Variable Example:

variable "instance_type" {
  description = "EC2 instance type"
  type        = string
  default     = "t2.micro"
}

Output Variable Example:

output "instance_ip" {
  value = aws_instance.example.public_ip
}

Output Values Example:

locals {
  service_name = "forum"
  owner        = "Community Team"
}

Data Sources

Data sources allow Terraform to use information defined outside of Terraform, defined by another separate Terraform configuration, or modified by functions. They let you fetch existing resources instead of creating new ones.

• Data Source Arguments

• Data Resource Behavior

• Local-only Data Sources

• Data Resource Dependencies

• AWS Data Sources

  • VPC Data Sources
  • AMI Data Sources
  • Availability Zones

Data Source Example:

data "aws_ami" "example" {
  most_recent = true
  owners      = ["self"]

  tags = {
    Name   = "app-server"
    Tested = "true"
  }
}

Using Data Source in Resources:

resource "aws_instance" "web" {
  ami           = data.aws_ami.example.id
  instance_type = "t2.micro"
}

Practical Activity –

Use Terraform to create:

• An EC2 instance → Launch a compute instance
• An S3 bucket → Store files in cloud
• An RDS database → Provision managed relational database

Recommended Course

For those who want a learning path, I highly recommend the Terraform Full Course on YouTube. This comprehensive tutorial is designed to provide hands-on experience with Terraform, covering all the essential concepts and practical examples that form the foundation of Infrastructure as Code. It's perfect for beginners and offers a solid foundation before moving on to more advanced Terraform topics like modules, workspaces, and enterprise features.