Comment 27 for bug 2044630

From what I got after that error (originally)... It errors in dpkg, so it leaves the old modules built for the kernels that it did upgrade to successfully (there).

Mine error'ed out when it tried to upgrade from 6.2.0-36 to 6.2.0-37. If worried me also, BUT... It did reboot.

Since linux-image-6.2.0-37-generic errored out during the install, it does not add it to the Grub2 grub.cfg menu, so on reboot, it booted into 6.2.0-36 as the running kernel, on the modules it built.

Each time it tried to do anything (updates), it would install anything new manually, but not actually do any of the updates. It looked like they were updating, then hit that zfs-dkms error.

From the output, it initially looked like it installed all the update except zfs-dkms, but that assumption was wrong. Next time I tried to update, it tried to update those same exact packages that were in that previous update (grouping), plsu anything newly added to those-- which tells me it did not upgrade any of them.

This morning, I see that Mantic and Noble got updates for zfs-dkms... But I haven't heard yet about Lunar. I don't see anything in any of my Jammy machine's updates.

The work-around I came up with... I haven't found an easier way. If you remove it before that update failure, then you do not need to reinstall linux-headers-XXX and update the instramfs files... Because it didn't hit the bug yet where it failed to build the modules. BUT...

And this is a big "BUT", something with zfs-dkms is somewhat 'evil'. When you remove it, somehow it exports all the zpools besides rpool!!!

*** It does not do that immediately. ***

Somehow, between the shutdown and reboot it exports all the pools besides rpool. I don't know why, but it just does. (That is why I refered to zfs-dkms' as soemhow being 'evil'. It has deep roots.)

While still booted, before that, everything is still mounted. You can export and import the pools. It does not matter. On the next boot, after removing package 'zfs-dkms', nothing is mounted except for rpool.

That work-around has instructions on how to import/mount everything back up and how to get it booting again.

*** Like I found out, package 'zfs-linux' is not needed anymore to build the zfs module during a kernel update. That was added by Canonical in-kernel. No one announced that change when that happened. We (Us Users) know that now.

Only a few of us still need zfs-dkms for out-of-series kernels, and testing DEV and Proposed packages, where weird circumstances are presented. But we are doing things that are "not normal", for the sake of Ubuntu and it's users.