Getting latest Ubuntu AMI with Terraform
Posted on Fri 25 August 2017 in Development • Tagged with AWS, Terraform, Ubuntu, devops
When we need to create an EC2 resource on AWS using Terraform, we need to specify the AMI id to get the correct image. The id is not easy to memorise and it changes depending on the zone we are working one. On every new release the id changes again. So, how can we be sure to get the correct ID for our region, of the latest image available for a given Linux distribution?
Getting latest Ubuntu AMI id
In this example I will show how to get the ID for the latest version of Ubuntu 16.04 server, for the London region and create an EC2 instance using that ID.
variable "aws_region" { default = "eu-west-2" } # London
provider "aws" {
region = "${var.aws_region}"
access_key = "youraccesskey"
secret_key = "yoursecretkey"
}
data "aws_ami" "ubuntu" {
most_recent = true
filter {
name = "name"
values = ["ubuntu/images/hvm-ssd/ubuntu-xenial-16.04-amd64-server-*"]
}
filter {
name = "virtualization-type"
values = ["hvm"]
}
owners = ["099720109477"] # Canonical
}
resource "aws_instance" "web" {
ami = "${data.aws_ami.ubuntu.id}"
instance_type = "t2.micro"
tags {
Name = "HelloUbuntu"
}
}
output "image_id" {
value = "${data.aws_ami.ubuntu.id}"
}
After we have initialised our script using terraform init if we run it, we will get the AMI id and the instance will be created:
➜ example1$: terraform apply
data.aws_ami.ubuntu: Refreshing state...
aws_instance.web: Creating...
ami: "" => "ami-03998867"
associate_public_ip_address: "" => "<computed>"
availability_zone: "" => "<computed>"
ebs_block_device.#: "" => "<computed>"
ephemeral_block_device.#: "" => "<computed>"
instance_state: "" => "<computed>"
instance_type: "" => "t2.micro"
ipv6_address_count: "" => "<computed>"
ipv6_addresses.#: "" => "<computed>"
key_name: "" => "<computed>"
network_interface.#: "" => "<computed>"
network_interface_id: "" => "<computed>"
placement_group: "" => "<computed>"
primary_network_interface_id: "" => "<computed>"
private_dns: "" => "<computed>"
private_ip: "" => "<computed>"
public_dns: "" => "<computed>"
public_ip: "" => "<computed>"
root_block_device.#: "" => "<computed>"
security_groups.#: "" => "<computed>"
source_dest_check: "" => "true"
subnet_id: "" => "<computed>"
tags.%: "" => "1"
tags.Name: "" => "HelloUbuntu"
tenancy: "" => "<computed>"
volume_tags.%: "" => "<computed>"
vpc_security_group_ids.#: "" => "<computed>"
aws_instance.web: Still creating... (10s elapsed)
aws_instance.web: Still creating... (20s elapsed)
aws_instance.web: Still creating... (30s elapsed)
aws_instance.web: Creation complete (ID: i-0f58f8bd55b3a7e38)
Apply complete! Resources: 1 added, 0 changed, 0 destroyed.
Outputs:
image_id = ami-03998867
That's all we need to spin up an EC2 instance on AWS using latest Ubuntu image available.