Setup Raspberry Pi OS Image Script

Scripts for modifying Raspberry Pi OS images before writing to SD card.

Easy Mode

git clone https://github.com/cinderblock/RaspberryPi-Image-Generator.git
cd RaspberryPi-Image-Generator
# Edit `setup.sh`. This gist adds *my* keys!
./new.sh

With already downloaded img zip

./new.sh path-to-raspbian.img.zip

Manual Mode

1. Download a Raspberry Pi OS image and unzip it:

   wget https://downloads.raspberrypi.org/raspios_lite_armhf_latest --trust-server-names --timestamping --quiet
   unzip *-*-*-raspios-buster-lite-armhf.zip

2. Download gist files:

   wget https://raw.githubusercontent.com/cinderblock/RaspberryPi-Image-Generator/master/{setup,chroot,grow,new}.sh --timestamping --quiet
   chmod +x {setup,chroot,grow,new}.sh

3. Edit setup.sh as desired. default adds my keys!
4. Run scripts.

Available scripts

sudo ./chroot.sh 2020-05-27-raspios-buster-lite-armhf.img [executable] [mount point]
sudo ./grow.sh 2020-05-27-raspios-buster-lite-armhf.img [megabytes]
./new.sh [image-path]
# `setup.sh` is meant to be run on a Raspberry Pi image in a chroot.
sudo ./edit-boot.sh 2020-05-27-raspios-buster-lite-armhf.img
./get-latest.sh

The default setup.sh script will fail unless you grow the standard .img by ~400MB first (as of 2021-07-15).

Runs the setup.sh (or other) script in a chroot in specified image.

Chroot

Gives you a chroot in the image to change whatever manually.

 ./chroot.sh my-raspios.img

If anything goes wrong, the script should cleanup after itself and not leave dangling mounts or loopback devices.

Planned changed: Use systemd-nspawn instead of chroot.

Maintains a separate ".bash_history" that is re-used for all images in a .persist folder. This behavior can be overridden by setting LEAVE_HISTORY_ALONE=yes (any non-zero length string).

Prepare

The ./chroot.sh script can also be run in "prepare" mode. Give it a second argument of an executable to run inside the chrooted environment as root. For example: ./chroot.sh my-raspios.img some-executable.

Grow

Grow the image (and main partition) by some number of megabytes.

 ./grow.sh my-raspios.img 400

This only affects the local .img file. On first boot, Raspbian will automatically grow the parition to fill the full card.

Adding 100MB adds aproximately 10 seconds to the write time when transfering to an SD card.

New

Does all the steps needed to get a brand new image in a single command. Assumes other scripts are in the same folder.

./new.sh

The steps are:

1. Download a new img file
2. unzip it on the fly
3. Save to a custom img file (overwritting if it exists)
4. Grows the image
5. Runs setup.sh inside the chroot
6. Zips the img to save space

Setup

This script is meant to be run inside a raspberry pi chroot, as root.

It might run succesfully running directly on a Pi, but that is not a supported use case.

Current Features

• Adds ssh keys
• Enables sshd, without passwords
• Sets US locale
• Adds WiFi configuration to /boot
• Adds a new script to change a Pi's hostname with a file /boot/hostname
• Sets timezone to America/Los_Angeles
• Updates & Upgrades
• Installs git, vim, screen, and node
• Sets the passwd for pi
• Sets python3 as the default Python version
• Sets vim as the default editor

Edit Boot get-boot.sh

A simplified mounting of the filesystem that only accesses the image's /boot parition.

Get Latest get-latest.sh

Download the official latest version of raspios-lite. Don't overwrite if it already exists. Continue downloading if previously interrupted.

See also

• https://github.com/RPi-Distro/pi-gen - Full featured .img generator
• https://wiki.debian.org/RaspberryPi/qemu-user-static - Debian instructions to grow/mount/chroot/qemu-run
• https://gist.github.com/htruong/0271d84ae81ee1d301293d126a5ad716 - Instructions to grow and chroot
• https://gist.github.com/htruong/7df502fb60268eeee5bca21ef3e436eb - Script to just mount & chroot (no loopback)
• https://gist.github.com/kmdouglass/38e1383c7e62745f3cf522702c21cb49 - Script: loopback, mount, chroot. No cleanup.