HOWTO Freeze Linux
- home directory is on a btrfs partition (
/dev/sda6in this example) /mntis available on boot for temporaryly mounting a fs- read-only version of home is a read-only snapshot named
home-roin btrfs root - the name
home-rwis not used on the btrfs fs wipeis installed in/usr/local/bin- systemd is used and
wipe.serviceis installed inetc/systemd/system - run
systemd enable wipe.serviceto enable wiping - if anything fails on boot, home is mounted from
fstab(99% of cases; except when exit code is 4) - user login is delayed until wiping is done
- wipe
#!/bin/bash if mount /dev/sda6 /mnt; then btrfs subvolume delete /mnt/home-rw if btrfs subvolume snapshot /mnt/home-ro /mnt/home-rw; then if umount /home; then if mount -o subvol=home-rw /dev/sda6 /home; then ret=0 else ret=4 fi else ret=3 fi else ret=2 fi else ret=1 fi umount /mnt if [ $? -ne 0 ]; then ret=1"$ret" fi exit $ret
- wipe.service
[Unit] Description=Wipe home directory modifications Requires=local-fs.target After=local-fs.target Before=systemd-user-sessions.service [Install] WantedBy=systemd-user-sessions.service [Service] Type=oneshot RemainAfterExit=yes ExecStart=/usr/local/bin/wipe
