I redeployed the system where this failures was original observed and recreated the issue. Running 'sudo vgck --updatemetadata s5lp8-vg' did work around this bug, when run after the upgrade but prior to the reboot.
Here is the vgdisplay output requested by Steve: ubuntu@s5lp8:~$ sudo vgdisplay --- Volume group --- VG Name s5lp8-vg System ID Format lvm2 Metadata Areas 1 Metadata Sequence No 4 VG Access read/write VG Status resizable MAX LV 0 Cur LV 3 Open LV 3 Max PV 0 Cur PV 1 Act PV 1 VG Size <64.00 GiB PE Size 4.00 MiB Total PE 16383 Alloc PE / Size 16377 / 63.97 GiB Free PE / Size 6 / 24.00 MiB VG UUID 3B7wkv-AIvn-5A7N-pmWB-7y7h-ylkd-jUIfRd ** Changed in: lvm2 (Ubuntu) Status: Incomplete => Confirmed -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to lvm2 in Ubuntu. https://bugs.launchpad.net/bugs/1874381 Title: LVM device unavailable after 18.04 to 20.04 upgrade Timed out waiting for device /dev/mapper/s5lp8--v g-home Status in Ubuntu on IBM z Systems: Confirmed Status in lvm2 package in Ubuntu: Confirmed Status in lvm2 source package in Focal: Confirmed Bug description: After upgrading an LPAR configured with LVM from 18.04 to 20.04 /home is no longer mounted. During boot the console shows Timed out waiting for device /dev/mapper/s5lp8--vg-home Please see the attached dist-upgrade logs and console output for more detail. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-z-systems/+bug/1874381/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : firstname.lastname@example.org Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp