Building AMI with Packer

This directory contains the files for building AMI using Packer that is later published as a AWS Marketplace asset.

Folder Structure

• hcl2-files - Includes different files which are used by a Packer pipeline to build an AMI. The files are:
  • build.pkr.hcl: contains the build block, defining the builders to start, provisioning them using provisioner, and specifying actions to take with the built artifacts using post-process.
  • variables.pkr.hcl: contains the variables block, defining variables within your Packer configuration.
  • sources.pkr.hcl: contains the source block, defining reusable builder configuration blocks.
  • packer.pkr.hcl: contains the packer block, used to configure some behaviors of Packer itself, such as the minimum required Packer version needed to apply to your configuration.
• scripts: contains scripts used by provisioner for installing additonal packages/softwares.

Prerequisites

• Packer: Packer is an open source tool for creating identical machine images for multiple platforms from a single source configuration.

• AWS Credentials: You need to have AWS credentials configured on your machine. You can configure AWS credentials using AWS CLI or by setting environment variables.

Install Packer on Ubuntu/Debian

curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -
sudo apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main"
sudo apt-get update && sudo apt-get install packer

You can also install Packer for other OS from here.

Configure AWS Credentials

Using Environment Variables:

export AWS_ACCESS_KEY_ID=<access_key>
export AWS_SECRET_ACCESS_KEY=<secret_key>

Using AWS CLI:

aws configure sso

There are other ways to configure AWS credentials. You can read more about it here.

Build AMI

Format Packer blocks

You can format your HCL2 files locally. This command will update your files in place.

Format a single file:

packer fmt build.pkr.hcl 

Format all files in a directory:

packer fmt ./hcl2-files

Validate Packer blocks

You can validate the syntax and configuration of your files locally. This command will return a zero exit status on success, and a non-zero exit status on failure.

packer validate -var 'region=us-west-2' -var 'optimum_version=v0.0.17' ./hcl2-files

Run Packer build

You can run Packer locally. This command will build the AMI and upload it to AWS.

You need to set variables with no default values using -var flag. For example:

packer build -var 'region=us-west-2' -var 'optimum_version=v0.0.17' ./hcl2-files

To trigger a github action workflow manually, you can use GitHub CLI:

gh workflow run build-ami.yml -f tag=<tag>