Read-only Root-FS with overlayfs for Raspian

This repository contains some useful files that allow you to use a Raspberry PI using a readonly filesystem.

This files contains some ideas and code of the following projects:

• https://gist.github.com/niun/34c945d70753fc9e2cc7
• https://github.com/chesty/overlayroot

Congratulate the original authors if these files works as expected. Too, you can congratulate to me to join all files in a one repository and do some changes allowing to use the root and boot filesytem in readonly mode.

Setup

To use this code, you can execute the follow commands:

cd /home/pi
sudo bash

echo Installing all dependencies
apt-get install git rsync gawk busybox bindfs

echo Disabling swap
dphys-swapfile swapoff
dphys-swapfile uninstall
update-rc.d dphys-swapfile disable
systemctl disable dphys-swapfile

echo Cloning repository
git clone https://github.com/josepsanzcamp/root-ro.git

echo Doing the setup
rsync -va root-ro/etc/initramfs-tools/* /etc/initramfs-tools/
mkinitramfs -o /boot/initrd.gz
echo initramfs initrd.gz >> /boot/config.txt

echo Restarting RPI
reboot

Write access

Write access can be enabled using following commands

# /
sudo mount -o remount,rw /mnt/root-ro
# /boot
sudo mount -o remount,rw /mnt/boot-ro

Read-only again

Re-mounting it read-only is done using following commands

# /
sudo mount -o remount,ro /mnt/root-ro
# /boot
sudo mount -o remount,ro /mnt/boot-ro