Create an EC2 Instance with Terraform

External

• https://www.terraform.io/docs/providers/aws/r/instance.html

Internal

• Amazon EC2 Operations
• Terraform AWS Operations

Overview

EC2 instances can be created, updated and deleted. Instances also support provisioning.

Playground

https://github.com/ovidiuf/playground/tree/master/hashicorp/terraform/simplest-ec2-instance

Terraform Registry ec2-instance Module

https://registry.terraform.io/modules/terraform-aws-modules/ec2-instance/aws/2.8.0

Configuration

provider "aws" {

  profile = "default"
  region  = "us-west-2"
}

resource "aws_instance" "terraform-experiment-01" {

  ami                         = "ami-000000000000000"
  instance_type               = "t2.small"
  subnet_id                   = "subnet-0000000000000000"
  key_name                    = "my-keypair-01"
  security_groups             = ["sg-0000000000000000"]
  associate_public_ip_address = false
  iam_instance_profile        = aws_iam_instance_profile.some-profile.name

  tags = {

    Name = "terraform-experiment-01"
  }
}

The instance profile can be created by the same module or a dependency module. If it is created by a dependency sub-module, it can be referred as:

resource "aws_instance" "terraform-experiment-01" {
  ...
  iam_instance_profile        = ${module.aws-iam.some-profile}
}

Configuration Details

Public IP

If nothing is specified, the instance will get a public IP. To disable allocation of a public address specify:

resource "aws_instance" ... {
  ...
  associate_public_ip_address = false
  ...
}

Note that even if associate_public_ip_address is explicitly set to "true", if the associated subnet has a map_public_ip_on_launch = true, a public IP will be associated anyway.

Multiple Instances

variable "instances" {
  default = "2"
}

resource "aws_instance" "my-instance" {
  count         = "${var.instances}"
  ...
  tags = {
    Name  = "my-instance-${count.index + 1}"
  }
}