Comment 0 for bug 1872827

Nrpe rev 63
I don't think the rsync config should be changed unless the nrpe charm's options require it.

Reproducer:
juju deploy nagios
juju deploy ubuntu
juju deploy nrpe
juju add-relation nagios nrpe
juju add-relation nrpe ubuntu

Wait until everything is done building...

juju ssh ubuntu/0 -- sudo reboot 1s
wait for reboot

juju run -u ubuntu/0 -- systemctl status rsync
● rsync.service - fast remote file copy program daemon
Loaded: loaded (/lib/systemd/system/rsync.service; enabled; vendor preset: enabled)
Active: failed (Result: exit-code) since Mon 2020-04-13 23:57:42 UTC; 20s ago
Process: 258 ExecStart=/usr/bin/rsync --daemon --no-detach (code=exited, status=1/FAILURE)
Main PID: 258 (code=exited, status=1/FAILURE)

Apr 13 23:57:42 juju-7fe258-0 systemd[1]: Started fast remote file copy program daemon.
Apr 13 23:57:42 juju-7fe258-0 rsync[258]: Failed to parse config file: /etc/rsyncd.conf
Apr 13 23:57:42 juju-7fe258-0 rsyncd[258]: rsync: unable to stat config file "/etc/rsync-juju.d": No such file or directory (2)
Apr 13 23:57:42 juju-7fe258-0 rsyncd[258]: params.c:pm_process() - Failed. Error returned from params.c:parse().
Apr 13 23:57:42 juju-7fe258-0 rsyncd[258]: rsync error: syntax or usage error (code 1) at clientserver.c(1174) [Receiver=3.1.2]
Apr 13 23:57:42 juju-7fe258-0 systemd[1]: rsync.service: Main process exited, code=exited, status=1/FAILURE
Apr 13 23:57:42 juju-7fe258-0 systemd[1]: rsync.service: Failed with result 'exit-code'.

This also causes:
juju ssh ubuntu/0 -- systemctl is-system-running
degraded (which is something many want to report on.

A simple workaround is to just disable rsync. (I believe this to be safe, but I haven't evaluated any actual nagios/nrpe functionality.