Comment 3 for bug 1729516

There was a line missing for virtlockd to be properly picked up by latter dh_* calls.
Adding that in a ppa fixed the issue of the missing default conf file.

But the service still didn't start by default.
virtlogd still serves its sysv script and thereby has an extra enable call
  invoke-rc.d virtlogd start
which might be mapped to the service which then is enabled.
Debian never had that for virtlockd, and Ubuntu followed by dropping as well in 3.5.0-1ubuntu1.
While silly this could be the reason it isn't started correctly.

Yes as I assumed virtlogd is started via the sysv (more or less unintentionally, so it works by accident).
But the systemd portion for virtlockd considers it disabled/static
  + systemctl --system daemon-reload
  + deb-systemd-invoke start virtlockd.service virtlockd.socket
  virtlockd.service is a disabled or a static unit, not starting it.