[systemd-devel] what does systemd do if the syslogd errs on start?

[Lennart Poettering]

On Wed, 06.07.11 16:11, Rainer Gerhards (rgerhards at gmail.com) wrote:

> Hi all,
> 
> I hope this is the right list. I wonder what systemd does if the
> syslogd does not start when told to do so.
> 
> Reason behind this question: in rsyslog, I try hard to record messages
> even if rsyslog.conf is screwed up. For that reason, I accept
> partially complete configs. And if things go really bad and I can not
> get anything that "looks" working, I startup a special, hardcoded,
> minimal config. All of this just in an effort to prevent log message
> loss.
> 
> Now with systemd around, I hope I can do the cleaner thing and just
> err out and terminate rsyslogd. That would probably alert users much
> better. It would also clean up the code and be less surprising to
> users (it either works fully correct or not at all - what you usually
> expect).  I assume that in this situation systemd takes the log socket
> over again. Am I right with that? What would be the best way to log a
> message to systemd in such a situation? Via the usual syslog()
> mechanism (with rsyslog being a client in this case)?

Yes, if rsyslog dies, then systemd will notice it. As soon as there is
traffic on the /dev/log socket (which might be right-away) it will then
start the syslog-kmsg bridge again. So we should be reasonably safe here
that nothing is completely lost when rsyslog dies.