Updating systemd unit configuration

[shjin]

• Updated systemd unit file to have correct file name based on systemd template documentation.
• Included instruction on how to setup systemd service and monitor it.

[LXXero]

What do you think about dropping screen entirely? I feel like it's only even here for legacy reasons - we can still see all of it's output via "journalctl" anyway - so there's not much of a reason for using it anymore, just legacy purposes really, as we'd been using it that way for a while.

[LXXero]

should we be advising this location, or rather /etc/systemd/system? I believe the /usr/lib/systemd location is primarily used for packages as opposed to locally/manually installed files like this.

[shjin]

How about /usr/lib/alarmserver instead? I found many other software installed are there and they create needed symlink or hardlink to /usr/bin/ if then want the executable available for user to execute anywhere.

/etc is where people store system configuration files but not executables or python scripts.

[LXXero]

I'm referring specifically to the .service file location - there's really only 2 valid locations for systemd - and that's /usr/lib/systemd/system (which is typically where RPM/Debs drop files) and /etc/systemd/system which is typically used for manually installed files (similar to /usr vs /usr/local, despite the slightly different context of /usr/lib vs /etc)

[shjin]

I think it makes sense to remove "screen". I was thinking some people would like to see the log interactively without going into journal or log file, but "screen" comes with the cost. For example, it is hard to see the error when alarmserver fails to start because screen session goes away and the exception message is lost.

[shjin]

I have updated this pull request with new alarmserver.service. Now "screen" is removed and updated instructions accordingly for new installation location.