The script adds itself to initramfs as described here:
# Make sure our script is part of the initramfs for the current kernel.
if ! [ -r /usr/share/initramfs-tools/scripts/local-bottom/rollback-zfs ] ||
! cmp "$0"...
If you don't want to use a rescue disk (or don't have one with a suitable kernel), but if you still have the ability to boot into your system, then the best option would be to roll back from inside the "initramfs". You can probably do this by...
I wrote a simple bash script to simplify the snapshot+upgrade process.
Rollback and purging of old snapshots has to be done manually.
#!/bin/bash
echo -e
#Set today's date and time as invironment variable
export now="$(date '+%Y-%m-%d_%H:%M')"...