backup.conf

[ExclusionList]
/lost+found
/*/.cache
/*/.local/share/Trash

backup.sh

#!/usr/bin/env bash
set -euo pipefail
IFS=$'\n\t'

zfs set readonly=off usb/backup
CUR_DATE=$(date +%Y%m%d)
umask 77

lvcreate -p r -s ace/root -l 936 -n root_snap
lvcreate -p r -s ace/home -l 936 -n home_snap

mount -r /dev/ace/root_snap /mnt
wimappend --quiet --unix-data --update-of=-2 --config=backup.conf /mnt system.wim root_${CUR_DATE}
umount /mnt
mount -r /dev/ace/home_snap /mnt
wimappend --quiet --unix-data --update-of=-2 --config=backup.conf /mnt system.wim home_${CUR_DATE}
umount /mnt

lvremove -y ace/root_snap
lvremove -y ace/home_snap

zfs set readonly=on usb/backup