d/rules, d/libvirt-daemon-system.{postinst,prerm}: never stop system services and sockets (LP: #1959054)
TL;DR:
- it is a mess, a lot of discussions and bugs to read for full awareness
- since transitions need libvirt soon we upload it with a mitigation now
- it is expected that debhelper in jammy is fixed and we can drop this
before release
- long term discussion how to deal with it in the salsa PR
Due to debhelper bug 994204 on upgrades guests are shut down
(libvirt-guests.service) or even crash (virtlogd.service) because those
services are restarted.
Until that bug is resolved in debhelper we need to take over the
handling of those services ourselves.
References:
- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=994204
- https://bugs.launchpad.net/ubuntu/+source/debhelper/+bug/1959054
- https://salsa.debian.org/utopia-team/dbus/-/commit/4c5195a13c69364dce50063afac368930ec75c91
Submitted to Debian via:
https://salsa.debian.org/libvirt-team/libvirt/-/merge_requests/132
The initial version of this was based on the dbus handling of it, but
it turns out that --no-stop-on-upgrade --no-start leaves a stop command
in prerm and thereby we'd have them stopped twice.
Auto added section is identical:
if [ -z "${DPKG_ROOT:-}" ] && [ "$1" = remove ] && [ -d /run/systemd/system ] ; then
deb-systemd-invoke stop 'libvirt-guests.service' 'virtlockd.service' 'virtlogd.service' >/dev/null || true
fi
Remove that duplicate that we added before following dbus.
It turns out also nowadays restarting the sockets is dangerous.
$ deb-systemd-invoke restart 'virtlogd.socket'
or
$ systemctl restart virtlogd.socket
no more complain about being unable to restart for the service being running.
Instead they do restart the service, which makes our restarting of sockets
again kill virtlogd for example.
Therefore we also can not leave the system-services sockets to debhelper
as they would be restarted despite --no-stop-on-upgrade and thereby
restart the related services breaking guests.
As suggested on the Debian PR this removes the remaining debhelper calls
for our system services and sockets.
The remaining little bit it did for us in postinst/postrm is
added directly to these maintainer script now in the non-restart
way that we need.
Signed-off-by: Christian Ehrhardt <email address hidden>
