groovy live-server amd64 beta (20200930) fails to load multipathd, install fails

[Paride Legovini]

The Groovy amd64 candidate beta image:

Ubuntu-Server 20.10 "Groovy Gorilla" - Beta amd64 (20200930)

fails to install with all defaults. The latest alpha image (20200928) didn't show this problem.

Looking at the logs, curtin fails with error:

Running command ['multipath', '-r'] with allowed return codes [0] (capture=False)
Oct 01 12:30:58 | DM multipath kernel driver not loaded
[...]
curtin.util.ProcessExecutionError: Unexpected error while running command.
Command: ['multipath', '-r']
Exit code: 1

This can be reproduced by calling `multipath -r` manually. Running the command attempts to start multipathd, which fails with error:

  DM multipath kernel driver not loaded

The journal shows that multipathd fails to start with the following errors:

Oct 01 12:51:09 ubuntu-server modprobe[1870]: modprobe: WARNING: Module scsi_dh_alua not found in directory /lib/modules/5.8.0-20-generic
Oct 01 12:51:09 ubuntu-server modprobe[1870]: modprobe: WARNING: Module scsi_dh_emc not found in directory /lib/modules/5.8.0-20-generic
Oct 01 12:51:09 ubuntu-server modprobe[1870]: modprobe: WARNING: Module scsi_dh_rdac not found in directory /lib/modules/5.8.0-20-generic
Oct 01 12:51:09 ubuntu-server modprobe[1870]: modprobe: WARNING: Module dm-multipath not found in directory /lib/modules/5.8.0-20-generic
Oct 01 12:51:09 ubuntu-server multipathd[1871]: --------start up--------
Oct 01 12:51:09 ubuntu-server multipathd[1871]: read /etc/multipath.conf
Oct 01 12:51:09 ubuntu-server multipathd[1871]: DM multipath kernel driver not loaded
Oct 01 12:51:09 ubuntu-server multipathd[1871]: DM multipath kernel driver not loaded
Oct 01 12:51:09 ubuntu-server systemd[1]: multipathd.service: Main process exited, code=exited, status=1/FAILURE

The dm-multipath module is not present in the ISO's initrd.

The full installer logs are attached.

[Paride Legovini (paride)]

/lib/modules is empty in the live system: all the kernel modules are missing.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1898045

[Paride Legovini (paride)]

Image was corrupted due to a "network unreachable" error at build time, so some image components were missing. A no-change rebuild produced a working image.

[Rui Lopes (rgl)]

This is happening again with 22.04.

The dm-multipath.ko file is missing from https://releases.ubuntu.com/22.04/ubuntu-22.04-live-server-amd64.iso.

For reference, these are the found dm- files:

root@pxe:~# find /lib/modules/5.15.0-25-generic/kernel/drivers/ -type f | grep dm-
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-bio-prison.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-bufio.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-cache-smq.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-cache.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-crypt.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-log.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-mirror.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-raid.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-region-hash.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-snapshot.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/dm-thin-pool.ko
/lib/modules/5.15.0-25-generic/kernel/drivers/md/persistent-data/dm-persistent-data.ko

Should I open another issue?

[Steve Langasek (vorlon)]

Yes, please open a new bug report.

[Rui Lopes (rgl)]

Thank you! I've open https://bugs.launchpad.net/ubuntu-cdimage/+bug/1969965.

[Steve Langasek (vorlon)]

For the record, I cannot reproduce this. dm-multipath.ko is present in both the squashfs and the initramfs on the release ISO, and booting it shows the file under /lib/modules as expected.

[Rui Lopes (rgl)]

My local setup was fubar; somehow it ended up using an older iso. I deleted everything and started from scratch, and now this works as expected (dm-multipath.ko is found and loaded).

Sorry for wasting your time :-(