Description of problem: I get lots of "Number of allowed concurrent connections exceeded; num='10', max='10'" in /var/log/messages so maybe syslog-ng defaults as shipped by fedora are too small (this is a single-user home system) Version-Release number of selected component (if applicable): syslog-ng-2.0.4-2.fc8
Experimenting shows the default 10 is too small to handle all the logs spilled at system statup and unix-stream("/dev/log"); needs to be changed in unix-stream("/dev/log" max-connections(48)); (32 is too small, I blame 48 on ATM)
The new max-connections enforcement introduced in syslog-ng 2.0.4 is quite "nasty" (the 10 connections default is in fact too low). With the default configuration I didn't detect any warning but as soon I started using yum to update/install packages I started seeing the "Number of allowed concurrent connections exceeded" message. Bumping the max-connections to 20 solved the problem (with the default configuration). source s_sys { file ("/proc/kmsg" log_prefix("kernel: ")); - unix-stream ("/dev/log"); + unix-stream ("/dev/log" max-connections(20)); internal(); I will try to update syslog-ng in my main log server to version 2.0.4 and see the result. From the syslog-ng-2.0.4 NEWS file ---------------------------------- 2.0.4 Mon, 14 May 2007 11:47:48 +0200 IMPORTANT NOTES: * This version of syslog-ng fixes a bug in enforcing the max-connections() limit for various stream-like sources (unix-stream and tcp). Previously this limit was not enforced, thus production environments may use an inadequate value. Validate your max-connection() settings before upgrading and check your logs for rejected connections. ...
IMHO for the default local system source it's better to be too big than too small, and 32 was still too small on my system (without too many log-spilling daemons installed)
syslog-ng 2.04 is now available in F-7 updates-testing. Changelog: The default configuration file now defines the number of max-connections for unix-streams as 32. ... unix-stream ("/dev/log" max-connections(32)); ...