immutable-Infrastructure-demo

Demo project that uses Packer, Ansible, and Terraform to build immutable infrastructure

Workflow:

• Bake the golden image with packer. It use ansible to provision the software.
• Based on the resulting image, terraform create a VM. It use a regex to find the image id and always use the most recent.

Requirements

• Install Packer to build the image: https://www.packer.io/docs/install
• Install Terraform to provision the VM: https://learn.hashicorp.com/tutorials/terraform/install-cli
• Get a Digital Ocean API token: https://cloud.digitalocean.com/account/api/tokens

How to build the image

1. Set an environment variable to the the API token

export DIGITALOCEAN_API_TOKEN=4059d45e5a75de0f24fe8f2ec678062e5cf8d66db885cdf4826befb30557d2gh

Change the value for your API token.

2. Buid the image:

$ cd packer
$ packer build  ubuntu2004-digitalocean.json

How to create the VM

Create variables file

In the root path of the code, create a file named terraform.tfvars and place the following variables:

do_token: must have the token created in the previous step.
droplet_ssh_key_id: The id of the key in DigitalOcean that will be used to connect to the virtual machine
droplet_name: The name of the droplet in DigitalOcean
droplet_size: The size of the droplet to use
droplet_region: The region where the droplet will be deployed

To obtain the values of the region, the ssh key, the name of the image and the size of the virtual machine, install the Digital Ocean command-line client: https://www.digitalocean.com/docs/apis-clis/doctl/

Export the DO token as an environment variable:

export DIGITALOCEAN_API_TOKEN=xxxdfc7f164a7001f76048313b0970bd46092f20569b9780ac242b00c9a7axxx

Change the value to your token.

To list all available ssh keys in the account:

$ doctl  -t $DIGITALOCEAN_API_TOKEN compute ssh-key list

To list all OS available:

$ doctl  -t $DIGITALOCEAN_API_TOKEN compute  region list

To list all sizes available:

$ doctl  -t $DIGITALOCEAN_API_TOKEN compute  size list

terraform.tfvars

do_token = "xxxdfc7f164a7001f76048313b0970bd46092f20569b9780ac242b00c9a7axxx"
droplet_ssh_key_id = "1632017"
droplet_name = "server-by-terraform"
droplet_size = "s-1vcpu-1gb"
droplet_region = "nyc1"

Execute terraform

To deploy the server we just have to execute the following commands:

$ cd terraform
$ terraform init
$ terraform plan
$ terraform apply