Why patterns solve common problems in Terraform - See It in Action

Why patterns solve common problems

📖 Scenario: You are working as a cloud engineer. Your team wants to create a reusable way to deploy a simple web server on a cloud virtual machine. This pattern will help everyone avoid repeating the same setup steps and reduce mistakes.

🎯 Goal: Build a Terraform configuration that uses a pattern to deploy a virtual machine with a web server installed. This pattern will be easy to reuse for future projects.

📋 What You'll Learn

Create a Terraform resource for a virtual machine with a fixed name

Add a variable to configure the machine size

Use a provisioner to install a web server

Add a tag to identify the machine as part of the web server pattern

💡 Why This Matters

🌍 Real World

Cloud engineers often create reusable Terraform patterns to speed up deployment and reduce errors when setting up infrastructure.

💼 Career

Understanding how to build and use patterns in Terraform is essential for roles like Cloud Engineer, DevOps Engineer, and Infrastructure Developer.

1

Create a virtual machine resource

Create a Terraform resource called aws_instance named web_server with the ami set to "ami-12345678" and instance_type set to "t2.micro".

Terraform

# Your code here

Need a hint?

Use the resource block with type aws_instance and name web_server.

2

Add a variable for instance size

Create a Terraform variable called instance_size with default value "t2.micro". Then update the instance_type in aws_instance.web_server to use this variable.

Terraform

resource "aws_instance" "web_server" {
  ami           = "ami-12345678"
  instance_type = var.instance_size
}

# Your code here

Need a hint?

Define a variable block and use var.instance_size in the resource.

3

Add a provisioner to install a web server

Add a provisioner "remote-exec" block inside aws_instance.web_server that runs the command sudo yum install -y httpd.

Terraform

variable "instance_size" {
  default = "t2.micro"
}

resource "aws_instance" "web_server" {
  ami           = "ami-12345678"
  instance_type = var.instance_size

  # Your code here
}

Need a hint?

Use the provisioner "remote-exec" block with inline commands.

4

Add a tag to identify the pattern

Add a tags block inside aws_instance.web_server with the key "Name" and value "web-server-pattern".

Terraform

variable "instance_size" {
  default = "t2.micro"
}

resource "aws_instance" "web_server" {
  ami           = "ami-12345678"
  instance_type = var.instance_size

  provisioner "remote-exec" {
    inline = ["sudo yum install -y httpd"]
  }

  # Your code here
}

Need a hint?

Add a tags map with the Name key inside the resource.