<p><br>
On Oct 31, 2011 2:54 AM, "suvayu ali" <<a href="mailto:fatkasuvayu%2Blinux@gmail.com">fatkasuvayu+linux@gmail.com</a>> wrote:<br>
><br>
> On Mon, Oct 31, 2011 at 05:22, T.C. Hollingsworth<br>
> <<a href="mailto:tchollingsworth@gmail.com">tchollingsworth@gmail.com</a>> wrote:<br>
> > Usually its easier to debug daemon problems by just running them on<br>
> > the command line. Look for the ExecStart line in<br>
> > /lib/systemd/system/<name>.service or if it uses classic initscripts<br>
> > check the corresponding file in /etc/init.d for the command that is<br>
> > run. That way you can easily run it through strace if you need to.<br>
> ><br>
> > That being said, on Fedora 16, systemd redirects stdout and stderr to<br>
> > syslog, so you can view the output from the daemons in<br>
> > /var/log/messages. Unfortunately, IIRCC F15 systemd does not do this,<br>
> > so edit /etc/systemd/system.conf and add a line that says<br>
> > "DefaultStandardOutput=syslog". The next time you boot, all daemons'<br>
> > stdout and stderr will be stored in syslog so you can view it<br>
> > afterward, either in /var/log/messages or with a viewer like<br>
> > KSystemLog. Messages from the kernel are also stored there, so you<br>
> > can see everything in one place.<br>
> ><br>
> > You can also set DefaultStandardOutput to "syslog+console" to have it<br>
> > output to the console as well, but that can be problematic because<br>
> > systemd starts many services in parallel. (If you decide to do that,<br>
> > make sure to remove "rhgb quiet" from your kernel command line as well<br>
> > so Plymouth gets out of the way and kernel messages are printed to the<br>
> > console also.)<br>
> ><br>
> > It's also rather easy to run systemd native services through strace,<br>
> > just run copy the .service file from /lib/systemd/system to<br>
> > /etc/systemd/system and append strace the command on the ExecStart<br>
> > line. When you're done, just rm the file in /etc and the one in /lib<br>
> > will take back over. Classic initscripts are a little harder: you<br>
> > have to find the appropriate line in the script and change it, and<br>
> > then change it back when you're done.<br>
> ><br>
><br>
> That is an amazingly clear "systemd debugging howto". Thanks a lot, I<br>
> have been putting off debugging ddclient because of my unfamiliarity<br>
> with systemd. Not any more. :)<br>
><br>
> PS: Have you considered putting this on the fedoraproject wiki?</p>
<p>I have marked this thread. I hope T.C. is interested in writing something up, since he clearly has a better understanding than I. If not, I will. This is great info, thanks!</p>