Welcome to the #90DaysOfDevOpsChallenge! Today is Day 65 and we are diving deeper into Terraform resources. Yesterday, we learned how to create a Terraform script with Blocks and Resources. Today, we'll explore how to create and manage Terraform resources more thoroughly.

Understanding Terraform Resources 📚

A resource in Terraform represents a component of your infrastructure, such as:

A physical server 🖥️
A virtual machine 🖥️
A DNS record 🌐
An S3 bucket 🪣

Attributes of resources define their properties and behaviors, such as:

The size and location of a virtual machine 📍
The domain name of a DNS record 🌐

When you define a resource in Terraform, you specify:

Type of resource (e.g., aws_instance)
Unique name for the resource (e.g., web_server)
Attributes that define the resource (e.g., instance_type, ami)

Terraform uses the resource block to define resources in your configuration.

Install Terraform:

sudo apt-get update
sudo apt-get install -y gnupg software-properties-common curl
curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -
sudo apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main"
sudo apt-get update
sudo apt-get install terraform
terraform -version

Task 1: Create a Security Group 🔒

To allow traffic to your EC2 instance, you need to create a security group. Follow these steps:

Open yourmain.tf file 📄
Add the following code to create a security group:

resource "aws_security_group" "web_server" {
  name_prefix = "web-server-sg"

  ingress {
    from_port   = 80
    to_port     = 80
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }
}

Resource block: aws_security_group defines the type of resource.
Name: web_server is a unique name for the resource.
Attributes:
- name_prefix: Prefix for the security group name.
- ingress: Rules to allow incoming traffic.
  - from_port and to_port: Ports to allow (80 for HTTP).
  - protocol: Protocol to use (TCP).
  - cidr_blocks: IP ranges to allow (0.0.0.0/0 allows all IPs).

Initialize the Terraform project:

terraform init

This command initializes the project and downloads necessary plugins.

Apply the configuration to create the security group:

terraform apply

This command creates the security group based on the configuration.

Task 2: Create an EC2 Instance 🖥️

Now, let's create an EC2 instance with Terraform. Follow these steps:

Open yourmain.tf file 📄
Add the following code to create an EC2 instance:

terraform {
  required_providers {
    aws = {
      source  = "hashicorp/aws"
      version = "~> 4.16"
    }
  }
  required_version = ">= 1.2.0"
}

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

resource "aws_security_group" "web_server" {
  name_prefix = "web-server-sg"

  ingress {
    from_port   = 80
    to_port     = 80
    protocol    = "tcp"
    cidr_blocks = ["0.0.0.0/0"]
  }
}

resource "aws_instance" "web_server" {
  ami           = "ami-00beae93a2d981137"
  instance_type = "t2.micro"
  key_name      = "90days0fdevopschallenge"
  security_groups = [
    aws_security_group.web_server.name
  ]

  user_data = <<-EOF
              #!/bin/bash
              echo "<html><body><h1>Welcome to my website!</h1></body></html>" > index.html
              nohup python -m SimpleHTTPServer 80 &
              EOF
}

Resource block: aws_instance defines the type of resource.
Name: web_server is a unique name for the resource.
Attributes:
- ami: Amazon Machine Image ID (replace with your own).
- instance_type: Type of instance (t2.micro is a free tier eligible type).
- key_name: Key pair for SSH access (replace with your own).
- security_groups: List of security groups (references the security group created earlier).
- user_data: Script to run on instance start-up (hosts a simple website).

Apply the configuration to create the EC2 instance:

terraform apply

This command creates the EC2 instance based on the configuration.

Task 3: Access Your Website 🌐

Now that your EC2 instance is up and running, you can access the website hosted on it. Follow these steps:

Find the Public IP of your EC2 instance:
- After running terraform apply, Terraform will output the public IP address of the instance.
Open your web browser and enter the public IP address:

http://<Public-IP>

You should see a webpage that says "Welcome to my website!"

Happy Terraforming! 🎉

With this guide, you have learned how to create a security group and an EC2 instance on AWS using Terraform. Keep experimenting and exploring more Terraform resources to build complex infrastructures efficiently. Happy Terraforming! 🚀

Day 65 - Working with Terraform Resources 🚀