[Bug 1828558] [NEW] installing ubuntu on a former md raid volume makes system unusable

[lvm]

Public bug reported:

18.04 is installed using GUI installer in 'Guided - use entire volume'
mode on a disk which was previously used as md raid 6 volume. Installer
repartitions the disk and installs the system, system reboots any number
of times without issues. Then packages are upgraded to the current
states and some new packages are installed including mdadm which *might*
be the culprit, after that system won't boot any more failing into ramfs
prompt with 'gave up waiting for root filesystem device' message, at
this point blkid shows boot disk as a device with
TYPE='linux_raid_member', not as two partitions for EFI and root
(/dev/sda, not /dev/sda1 and /dev/sda2). I was able fix this issue by
zeroing the whole disk (dd if=/dev/zero of=/dev/sda bs=4096) and
reinstalling. Probably md superblock is not destroyed when disk is
partitioned by the installer, not overwritten by installed files and
somehow takes precedence over partition table (gpt) during boot.

** Affects: ubuntu-release-upgrader (Ubuntu)
     Importance: Undecided
         Status: New

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to ubuntu-release-upgrader in
Ubuntu.
https://bugs.launchpad.net/bugs/1828558

Title:
  installing ubuntu on a former md raid volume makes system unusable

Status in ubuntu-release-upgrader package in Ubuntu:
  New

Bug description:
  18.04 is installed using GUI installer in 'Guided - use entire volume'
  mode on a disk which was previously used as md raid 6 volume.
  Installer repartitions the disk and installs the system, system
  reboots any number of times without issues. Then packages are upgraded
  to the current states and some new packages are installed including
  mdadm which *might* be the culprit, after that system won't boot any
  more failing into ramfs prompt with 'gave up waiting for root
  filesystem device' message, at this point blkid shows boot disk as a
  device with TYPE='linux_raid_member', not as two partitions for EFI
  and root (/dev/sda, not /dev/sda1 and /dev/sda2). I was able fix this
  issue by zeroing the whole disk (dd if=/dev/zero of=/dev/sda bs=4096)
  and reinstalling. Probably md superblock is not destroyed when disk is
  partitioned by the installer, not overwritten by installed files and
  somehow takes precedence over partition table (gpt) during boot.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1828558/+subscriptions