Count for multiple instances in Terraform - Mini Project: Build & Apply

Count for multiple instances

📖 Scenario: You are setting up a simple cloud infrastructure using Terraform. You want to create multiple identical virtual machines (instances) to handle web traffic.

🎯 Goal: Build a Terraform configuration that creates exactly three virtual machine instances using the count meta-argument.

📋 What You'll Learn

Create a resource block for an AWS EC2 instance named aws_instance.web.

Use the count meta-argument to create exactly 3 instances.

Set the ami attribute to "ami-0c55b159cbfafe1f0".

Set the instance_type attribute to "t2.micro".

💡 Why This Matters

🌍 Real World

Creating multiple virtual machines is common when you want to scale your application to handle more users.

💼 Career

Cloud engineers often use Terraform's count feature to efficiently manage multiple resources without repeating code.

1

DATA SETUP: Define the AWS provider

Write a provider block for AWS with the region set to "us-east-1".

Terraform

# Your code here

Need a hint?

The provider block tells Terraform which cloud provider to use and where.

2

CONFIGURATION: Add the count variable

Create a variable called instance_count with a default value of 3.

Terraform

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

# Your code here

Need a hint?

Variables help you change values easily without editing resource blocks.

3

CORE LOGIC: Create multiple instances using count

Create a resource block named aws_instance.web that uses count = var.instance_count. Set ami to "ami-0c55b159cbfafe1f0" and instance_type to "t2.micro".

Terraform

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

variable "instance_count" {
  default = 3
}

# Your code here

Need a hint?

The count argument creates multiple copies of the resource.

4

COMPLETION: Add tags to instances

Add a tags block inside the aws_instance.web resource with Name = "WebServer-${count.index + 1}".

Terraform

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

variable "instance_count" {
  default = 3
}

resource "aws_instance" "web" {
  count         = var.instance_count
  ami           = "ami-0c55b159cbfafe1f0"
  instance_type = "t2.micro"

  # Your code here
}

Need a hint?

Tags help identify your instances in the cloud console.