Upgrading haproxykafka debian package on any host doesn't restart automatically the systemd service (as we would expect). That's because the debian package for haproxykafka doesn't manage the systemd unit (as it's not in a standard path and it doesn't follow the dh_systemd convention) so debhelper generated postinst script won't know about the service.
The roadmap would be:
- Patching the haproxykafka puppet module, to bring the relevant changes with an override to the systemd unit file
- Patch haproxykafka package to actually install systemd unit file in /lib/systemd.
- Deploying the new package version everywhere. The package should overwrite the configuration file brought by puppet (and incidentally, restart the service as soon as it gets upgraded).
- Run puppet with the systemd unit overrides