Simple script to put Raspberry Pi OS Lite to readonly mode and heavily reduce the chance of SD card failure. All read-write files are moved to /tmp which is stored in RAM. There are two short macros which you can use to switch between read-only and read-write filesystem.
Note that this works only for Raspberry Pi OS Lite.
wget https://raw.githubusercontent.com/dominikberse/rpi-read-only/main/rpi-read-only.sh
chmod +x rpi-read-only.sh
sudo ./rpi-read-only.sh
Wait for script to finish and reboot. The Raspberry Pi should start in ro (read-only) mode. Use ro or rw to switch between read-only and read-write.
The problem here is that many applications running on the Raspberry Pi require read-write filesystem access. So whenever you install new applications or services, it might be neccessary to move their temporary files (usually log files) and folders to /tmp. This can usually be done easily be creating an appropriate hard link.
To create any required files/folders in /tmp at startup, list them inside the ~/.tmpfiles.conf configuration file.
TODO: Detailled instructions