[systemd-devel] Antw: Re: Q: Implementing logrotate's postrotate with systemd

[Michael Biebl]

Am Di., 11. Juni 2019 um 16:18 Uhr schrieb Reindl Harald
<h.reindl at thelounge.net>:
>
>
>
> Am 11.06.19 um 15:00 schrieb Ulrich Windl:
> >>>> Reindl Harald <h.reindl at thelounge.net> schrieb am 11.06.2019 um 14:30 in
> > Nachricht <917331d8-845f-54d5-908c-e6c7d124a3c6 at thelounge.net>:
> >>
> >> Am 11.06.19 um 13:34 schrieb Ulrich Windl:
> >>> I have a forking service (with a PID file) that can reopen the logfile after
> >> receiving SIGHUP. In the past I had implemented "rc{service} rotate" to send
> >> SIGHUP to the daemon as "postrotate" action. After converting (actually being
> >> converted ;-)) to systemd I dropped the LSB script, and wonder which command
> >> to use as "postrotate" action:
> >>>
> >>> Should I implement a oneshot service (using "systemctl start {service}")
> >> that does depend on the actual service and send a SIGHUP on start, or is
> >> there a more elegent solution?
> >>
> >> that's what reload is all about
> >>
> >> [harry at srv-rhsoft:/etc/systemd/system]$ cat named.service | grep Reload
> >> ExecReload=/usr/bin/kill -HUP $MAINPID
> >
> > The manual page says it's about "configuration reload". I was talking about logfile rotation (my service does not suport configuration reload (other than restart))
>
> frankly it's nothing new or uncommon that services close and re-open
> their logfiles by "reload" and that's really not systemd specific,
> sysvinit had reload too
>
> it's you turn what happens with "systemctl reload yourservice" becaus
> ethere is no default action for that unless "ExecReload" is specified

Of course you can do whatever you please in ExecReload, but as said I
think it's good practice if "reload" has a certain consistent meaning
across services so admins not familiar with a particular service know
what to expect from "systemctl reload".

See also
https://github.com/rsyslog/rsyslog/commit/fd26a42bdc04eaf497cafd9ef806a54f3de1a7e9#diff-c64e6ed7f40ecd1530e093a77c9465f6



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