Comment 0 for bug 1777860

After having crashed, sssd will not start, because the old PIDfile is still present. The fact that the process does not exist any more does not cause the PIDfile to be cleaned up.
This bug is already known, but not fixed, upstream: https://pagure.io/SSSD/sssd/issue/3528
(also contains instructions for reproduction).

In our environment, with hundreds of computers running Ubuntu, the 'solution' brought forth in that discussion, to investigate and handle the issue manually, is not a serious option.

So I propose that we make systemd handle the PIDfile in case of a crash. With the attached one-line patch applied, systemd will clean up the PIDfile after a crash. That way, sssd doesn't have to make assumptions about namespaces, but the package still handles the issue.

Mandatory data:

Ubuntu version:
  Ubuntu 16.04.4 LTS

Package version:
  apt-cache policy $(dpkg -S /lib/systemd/system/sssd.service )
   sssd-common: Installed: 1.13.4-1ubuntu1.11

What I expect to happen:
After
  kill -9 $(cat /var/run/sssd.pid)
the command
  systemctl start sssd results in a running sssd
results in a running sssd.

What happens instead:
No sssd is running. Only after
  rm /var/run/sssd.pid
  systemctl start sssd results in a running sssd
does it run again.