[systemd-devel] systemd hangs after Welcome message when LogLevel=debug

[Lennart Poettering]

On Mon, 20.01.14 13:42, Barry Scott (barry.scott at onelan.co.uk) wrote:

> > But while systemd is starting your system the syslog might not be
> > ready. Probably systemd has some buffer, where it buffers the output.
> > Once syslog becomes available, it will be fed with the buffer's
> > contents first. If the output is small enought, as with LogLevel=info,
> > this actually works. But when you generate gobs of output, the buffer
> > will overflow and the output routine will wait until the buffer get's
> > emptied, which it never will ...
> > 
> > So, you might try to use DefaultStandardOutput=syslog-or-kmsg or
> > DefaultStandardOutput=journal instead. The latter will eventually also
> > send the output to syslog, which is why it's a default.
> 
> I guess you are saying that because all output must go to syslog and syslog is 
> not running that systemd will hang. But why does the configuration work if 
> LogLevel=info in that case?

systemd will never hang on this. syslog-or-kmsg means that syslog is
used when it is up, and kmsg otherwise. We will not block on anything,
it's just a really simple condition check each time we write a msg.

Lennart

-- 
Lennart Poettering, Red Hat