Can't mount partitions in fstab after 14.04->16.04 upgrade

[Jiri Wichern]

This is either a problem with fsck/mount, the Ubuntu distribution upgrade process or systemd. I'm not yet sure which.

I had a hell of a time trying to upgrade from 14.04 to 16.04. I managed to get through after several single-user sessions in rescue-mode (machine was not able to boot to multi-user level at this state and I couldn't, then, find the problem), installing all packages until 'dpkg --audit' gave no more problems and apt-get upgrade had nothing more to add. I was still unable to boot using systemd but upstart did work.

Analyzing the boot journal with journalctl -xb I saw various disks couldn't be fsck'ed or mounted. When I tried to mount one of them manually in rescue mode I got:

root@Diamond:/etc# mount /media/sda6
mount: can't find UUID=28aa6c430061e3ca

More research:

root@Diamond:/etc# blkid /dev/sda6
/dev/sda6: LABEL="Swap" UUID="28AA6C430061E3CA" TYPE="ntfs" PARTUUID="000c76d0-06"
root@Diamond:/etc# cat fstab | grep sda6
# /dev/sda6
UUID=28aa6c430061e3ca /media/sda6 ntfs defaults,umask=007,gid=46 01

Note the UUID as it seems booting in systemd requires fstab's UUIDs to be case sensitive. When booting using upstart, this is not the case. When you put an UUID with upper case letters in fstab, the problem (in a session booted using systemd) goes away.
I never manually edited /etc/fstab on this machine before so somehow Ubuntu once generated UUIDs with lower-case letters when I first installed it, or during an upgrade. However, now it needs to be upper-case.

Additional information:
root@Diamond:/etc# lsb_release -rd
Description: Ubuntu 16.04.1 LTS
Release: 16.04
root@Diamond:/etc# apt-cache policy util-linux
util-linux:
  Installed: 2.27.1-6ubuntu3.1
  Candidate: 2.27.1-6ubuntu3.1
  Version table:
 *** 2.27.1-6ubuntu3.1 500
        500 http://nl.archive.ubuntu.com/ubuntu xenial-updates/main amd64 Packages
        100 /var/lib/dpkg/status
     2.27.1-6ubuntu3 500
        500 http://nl.archive.ubuntu.com/ubuntu xenial/main amd64 Packages

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: mount 2.27.1-6ubuntu3.1
ProcVersionSignature: Ubuntu 4.4.0-31.50-generic 4.4.13
Uname: Linux 4.4.0-31-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: Unity
Date: Sun Aug 7 19:36:58 2016
SourcePackage: util-linux
UpgradeStatus: No upgrade log present (probably fresh install)

[Phillip Susi (psusi)]

That is a very interesting problem and a very well written bug report. Thank you.