Using a snapshot for an upgrade so I can roll back / 2020-12-04

This evening I upgraded the production webserver from Devuan ascii to Devuan beowulf and to have the option available to roll back everything I created a snapshot and left that running until I was satisfied with the new configuration and everything worked.

The steps were simple, found via Commit or revert a Linux LVM snapshot? - serverfault:

Before starting the upgrade, create a snapshot:

# lvcreate -L 10G -s -n turing_upgrade /dev/conway_ssd/turing_root

Do all the upgrade stuff, reboot, make sure everything works again.

The usage of the snapshot went up to 22.38 percent:

# lvs
  LV               VG         Attr       LSize   Pool Origin    Data%  Meta%  Move Log Cpy%Sync Convert
  turing_root      conway_ssd owi-aos---  30.00g
  turing_upgrade   conway_ssd swi-a-s---  10.00g      turing_root 13.17

After everything worked, remove the snapshot:

# lvremove /dev/conway_ssd/turing_upgrade