Raspberry Pi OS Image with Packer

In this setup, we will see how to create a custom Raspberry Pi image using Packer and its ARM builder plugin. This will let you modify the existing ARM image, provisioning and resize the filesystem partition in the Raspberry Pi as needed.

Prerequisites

Ubuntu 18.04/20.04 LTS
Git
Packer
Packer ARM Builder Plugin

Dependencies

Before we start building, you need to install the required dependencies on your host machine(Ubuntu 18.04/20.04 LTS). Just follow the steps given below to set up the build environment:

Install the required binaries on the host machine.

sudo apt update
sudo apt install git wget zip unzip build-essential kpartx qemu binfmt-support qemu-user-static e2fsprogs dosfstools

Download the Packer from the official website and configure it on your host machine.

For Ubuntu x64 based hosts

export PACKER_RELEASE="1.6.6"
cd /tmp/
wget https://releases.hashicorp.com/packer/${PACKER_RELEASE}/packer_${PACKER_RELEASE}_linux_amd64.zip
unzip packer_${PACKER_RELEASE}_linux_amd64.zip
sudo mv packer /usr/local/bin
packer --version

Alternatively, you can install Packer using apt packer managers. Follow the instructions from official Hashicorp documentation - https://learn.hashicorp.com/tutorials/packer/get-started-install-cli?in=packer/docker-get-started.

Download the Packer ARM builder plugin and configure the same on the host machine.

export PACKER_ARM_BUILDER_VERSION="0.1.6"
cd /tmp/
wget https://github.com/solo-io/packer-builder-arm-image/releases/download/v${PACKER_ARM_BUILDER_VERSION}/packer-builder-arm-image
sudo mv packer-builder-arm-image /usr/local/bin
sudo chmod +x /usr/local/bin/packer-builder-arm-image

Start building ARM image

For building the ARM image, the Packer uses the provisioners to mount the image on your local file system and to make changes in the base ARM image.

Clone the codebase from the GitHub repository and follow the instructions for building ARM images using Packer. Go to the raspberry-pi-os-image-builder directory and execute the Packer build command.

# Clone GitHub repository
git clone git@github.com:source4learn/raspberry-pi-os-image-builder.git
cd raspberry-pi-os-image-builder
sudo packer build packer-raspberry-pi-os-lite.json

Verify the file location and size once Packer build is completed. Archive the output image file to reduce the size on disk.

# Check file location and size
ls -la output-arm-image/image# Check file size
du -hs output-arm-image/image

# Create zip archive
zip -r rpi-arm-image.zip output-arm-image/image

Use the Raspberry Pi Imager or any other tool to create a bootable SD card.

Summary

If you encounter an error or problem in this setup, please report in the GitHub repository issues. Reach us in case you need any further assistance.

Email: source4learn@gmail.com

Twitter: @source4learn

LinkedIn: linkedin.com/in/source4learn