RPi SD image builder

This tool able to customize any RPi image (ARM arch) by ansible playbooks on (x86_64 host).

Requirements:

• Linux host system
• Docker with enabling of multiarch containers

Setup docker

• The older docker versions require to enable "experimental" mode.

  $ cat /etc/docker/daemon.json
  {
      "experimental": true
  }   
  systemctl restart docker.service

• Run multiarch setup

    $ sudo docker run --rm --privileged multiarch/qemu-user-static --reset -p yes

• Test configuration

    $ docker run --rm -t arm32v7/alpine uname -m
    ...
    armv7l

Prepare source image

Download RPi image and unpack it.

$ mkdir -p output && cd output 
$ wget https://downloads.raspberrypi.org/raspios_lite_armhf/images/raspios_lite_armhf-2021-05-28/2021-05-07-raspios-buster-armhf-lite.zip
$ unzip 2021-05-07-raspios-buster-armhf-lite.zip
$ cd ..

Customize SD image

This demo profile kiosk creates SD image for kiosk box.

$ sudo docker build -t sd_builder:local .
$ sudo docker run -it --rm --privileged \
   -e "IMAGE=2021-05-07-raspios-buster-armhf-lite.img" \
   -e "PROFILE=kiosk" \
   -e "IMAGE_RESIZE=7G" \
   -v $(pwd):/app -v /dev:/dev sd_builder:local

Options:

The options are setup by docker environment variables.

• IMAGE - filename of SD image (required)
• PROFILE - profile name (required)
• IMAGE_RESIZE - resize SD image (optional)
• NO_BOOT_PARTITION - No. boot partition (optional, default 1)
• NO_ROOT_PARTITION - No. root partition (optional, default 2)

Unfortunately, the progress of customizing is not shown in the main console. We can check the output by

$ tail -f ansible-log.txt 

Sometimes, the script can not unmount all folders, this error can be ignored. But we can clean up this manually by

$ sudo losetup -D  

structure of the profile

The profiles are stored in profiles folder. Important files:

• profiles/myprofile/playbook.yml - The main ansible playbook (required). This playbook is run inside SD image. In this file, we should install packages and setup configuration.
• profiles/myprofile/pre_tasks.yml - The file with ansible tasks (optional). Here we can manipulate with partitions or prepare external resources.
• profiles/myprofile/post_tasks.yml - The file with ansible tasks (optional). Here we can cleanup or get data from prepared SD image (package list, ...)
• profiles/myprofile/requirements.yml - The list for ansible roles (optional). They will be automatically installed.