blk-availability unmounts filesystems before applications have finished using them

[Scott Rochford]

This bug is similar to the following:

  Red Hat - https://bugzilla.redhat.com/show_bug.cgi?id=1701234#c2
  Debian - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=946882

The blk-availability service is short-cutting RequiresMountsFor=<paths> dependencies during system shutdown and unmounting filesystems before those services have stopped, resulting in data file corruption and/or data loss.

This can be worked around by adding "After=blk-availability.service" to the unit file for the service in question, but this is not self-evident and shouldn't be necessary.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: lvm2 2.03.07-1ubuntu1
ProcVersionSignature: Ubuntu 5.4.0-40.44-generic 5.4.44
Uname: Linux 5.4.0-40-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.4
Architecture: amd64
CasperMD5CheckResult: skip
Date: Tue Jul 21 16:37:17 2020
InstallationDate: Installed on 2014-05-01 (2272 days ago)
InstallationMedia: Ubuntu-Server 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2)
SourcePackage: lvm2
UpgradeStatus: Upgraded to focal on 2020-05-05 (77 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.