Upgrade Scale with legacy LUKS pool

I have been using scale 22.12 for the past year with a zfs pool I created many years ago with ZFS on Linux 1.x; at the time I created the pool there was no such thing as native ZFS encryption on linux and therefore I created the pool ontop of dm-crypt drives.

22.12 included the necessary kernel modules to successfully decrypt the drives, but now it seems with the 24.10 update that is no longer the case - the kernel has not been built with dm_mod support.

Is there any documentation on compiling the kernel for scale?

I know I should move to native zfs encryption, but there’s no easy way to do that without having a large amount of storage available first to offload the existing data whilst the pool is being rebuilt.

This is a backwards incompatibility between 22.12 and 24.10 and you should:

  1. Check whether this is mentioned in the various release notes for any releases; and if not…
  2. Raise a ticket to get dm_mod added back in.

If not, then your choices will be:

  1. Set 22.12 as your boot environment and go back.
  2. Try upgrading release by release to see where the kernel module got dropped and stop on the latest release that still has it.

Either way, you should probably think about how to remove the dm_crypt encryption and switch to ZFS encryption. I suspect that this can’t be done in place and so will be time consuming and awkward and may require buying new drives.