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Section: The syslog-ng manual page (8) Updated: 11/30/2009
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syslog-ng - syslog-ng system logger application  


syslog-ng [options]


NOTE: This manual page covers both editions of syslog-ng: syslog-ng Open Source Edition and the commercial syslog-ng Premium Edition. Features that are only included in the Premium Edition are marked with an asterisk (*). For details, see the official syslog-ng website:

This manual page is only an abstract; for the complete documentation of syslog-ng, see The syslog-ng Administrator Guide [1].

The syslog-ng application is a flexible and highly scalable system logging application. Typically, syslog-ng is used to manage log messages and implement centralized logging, where the aim is to collect the log messages of several devices on a single, central log server. The different devices - called syslog-ng clients - all run syslog-ng, and collect the log messages from the various applications, files, and other sources. The clients send all important log messages to the remote syslog-ng server, where the server sorts and stores them.  


--cfgfile <file> or -f <file>

Use the specified configuration file.

--chroot <dir> or -C <dir>

Change root to the specified directory after reading the configuration file. The directory must be set up accordingly. Note that it is not possible to reload the syslog-ng configuration after chrooting.

--debug or -d

Start syslog-ng in debug mode.


Enable syslog-ng to write core files in case of a crash to help support and debugging.


Set the minimal number of required file descriptors (fd-s); this sets how many files syslog-ng can keep open simultaneously. Default value: 4096. Note that this does not override the global ulimit setting of the host.

--foreground or -F

Do not daemonize, run in the foreground.

--group <group> or -g <group>

Switch to the specified group after initializing the configuration file.

--help or -h

Display a brief help message.


Run syslog-ng as root, without capability-support. This is the default behavior. On Linux, it is possible to run syslog-ng as non-root with capability-support if syslog-ng was compiled with the --enable-linux-caps option enabled. (Execute syslog-ng --version to display the list of enabled build parameters.)

--persist-file <persist-file> or -R <persist-file>

Set the path and name of the syslog-ng.persist file where the persistent options and data are stored.

--pidfile <pidfile> or -p <pidfile>

Set path to the PID file where the pid of the main process is stored.

--process-mode <pidfile>

Sets how to run syslog-ng: in the foreground (mainly used for debugging), in the background as a daemon, or in safe-background mode, when syslog-ng restarts itself if it crashes. By default, syslog-ng runs in safe-background mode.

--qdisk-dir <path> or -Q <path>

Specify the location of the file used for disk-based buffering. By default, this file is located at /var/lib/syslog-ng/.

--stderr or -e

Log internal messages of syslog-ng to stderr. Mainly used for debugging purposes in conjunction with the --foreground option.

--syntax-only or -s

Verify that the configuration file is syntactically correct and exit.

--user <user> or -u <user>

Switch to the specified user after initializing the configuration file (and optionally chrooting). Note that it is not possible to reload the syslog-ng configuration if the specified user has no privilege to create the /dev/log file.

--verbose or -v

Enable verbose logging used to troubleshoot syslog-ng.

--version or -V

Display version number and compilation information.






The syslog-ng Administrator Guide [1]

If you experience any problems or need help with syslog-ng, visit the syslog-ng mailing list [2]

For news and notifications about the documentation of syslog-ng, visit the BalaBit Documentation Blog[3].  


This manual page was written by the BalaBit Documentation Team <>.  


Copyright © 2000-2009 BalaBit IT Security Ltd. Published under the Creative Commons Attribution-Noncommercial-No Derivative Works (by-nc-nd) 3.0 license. See for details. The latest version is always available at  



          The syslog-ng Administrator Guide


          syslog-ng mailing list

BalaBit Documentation Blog




This document was created by man2html, using the manual pages.
Time: 22:02:28 GMT, April 16, 2011