SYSLOGD(8)						    BSD System Manager's Manual 						SYSLOGD(8)

NAME

     syslogd -- log systems messages

SYNOPSIS

     syslogd [-dnrSsTUv] [-b bind_address] [-f config_file] [-g group] [-m mark_interval] [-o output_format] [-P file_list] [-p log_socket
	     [-p log_socket2 ...]] [-t chroot_dir] [-u user]

DESCRIPTION

     syslogd reads and logs messages to the system console, log files, other machines and/or users as specified by its configuration file.  The
     options are as follows:

     -b bind_address  Specify one specific IP address or hostname to bind to.  If a hostname is specified, the IPv4 or IPv6 address which corre-
		      sponds to it is used.

     -d 	      Enable debugging to the standard output, and do not disassociate from the controlling terminal.

     -f config_file   Specify the pathname of an alternative configuration file; the default is /etc/syslog.conf.

     -g group	      Set GID to group after the sockets and log files have been opened.

     -m mark_interval
		      Select the number of minutes between ``mark'' messages; the default is 20 minutes.

     -n 	      Do not perform hostname lookups; report only numeric addresses.

     -o output_format
		      Select output message format.

		      rfc3164 traditional BSD Syslog format (default)

		      syslog  new syslog-protocol format

     -P 	      Specify the pathname of a file containing a list of sockets to be created.  The format of the file is simply one socket per
		      line.

     -p log_socket    Specify the pathname of a log socket.  Multiple -p options create multiple log sockets.  If no -p arguments are created, the
		      default socket of /var/run/log is used.

     -r 	      Disable the compression of repeated instances of the same line into a single line of the form ``last message repeated N
		      times''.

     -S 	      Sync kernel messages to disk immediately.

     -s 	      Select ``secure'' mode, in which syslogd does not listen on a UDP socket but only communicates over a UNIX domain socket.
		      This is valuable when the machine on which syslogd runs is subject to attack over the network and it is desired that the
		      machine be protected from attempts to remotely fill logs and similar attacks.

     -t chroot_dir    chroot(2) to chroot_dir after the sockets and log files have been opened.

     -T 	      Always use the local time and date for messages received from the network, instead of the timestamp field supplied in the
		      message by the remote host.  This is useful if some of the originating hosts can't keep time properly or are unable to gen-
		      erate a correct timestamp.

     -u user	      Set UID to user after the sockets and log files have been opened.

     -U 	      Unique priority logging.	Only log messages at the priority specified by the selector in the configuration file.	Without
		      this option, messages at the specified priority or higher are logged.  This option changes the default priority comparison
		      from '>=' to '='.

     -v 	      Verbose logging.	If specified once, the numeric facility and priority are logged with each locally-written message.  If
		      specified more than once, the names of the facility and priority are logged with each locally-written message.

     syslogd reads its configuration file when it starts up and whenever it receives a hangup signal.  For information on the format of the con-
     figuration file, see syslog.conf(5).

     syslogd reads messages from the UNIX domain socket /var/run/log, from an Internet domain socket specified in /etc/services, and from the spe-
     cial device /dev/klog (to read kernel messages).

     syslogd creates the file /var/run/syslogd.pid, and stores its process id there.  This can be used to kill or reconfigure syslogd.

     By using multiple -p options, one can set up many chroot environments by passing the pathname to the log socket (/var/run/log) in each chroot
     area to syslogd.  For example:
	   syslogd -p /var/run/log -p /web/var/run/log -p /ftp/var/run/log

     Note: the normal log socket must now also be passed to syslogd.

     The logged message includes the date, time, and hostname (or pathname of the log socket).	Commonly, the program name and the process id is
     included.

     The date and time are taken from the received message.  If the format of the timestamp field is incorrect, time obtained from the local host
     is used instead.  This can be overridden by the -T flag.

     Accesses from UDP socket can be filtered by libwrap configuration files, like /etc/hosts.deny.  Specify ``syslogd'' in daemon_list portion of
     the configuration files.  Refer to hosts_access(5) for details.

   SYSLOG PROTOCOL NOTES
     syslogd accepts messages in traditional BSD Syslog or in newer Syslog Protocol format.  See RFC 3164 (BSD Syslog) and RFC 5424 (Syslog Proto-
     col) for detailed description of the message format.  Messages from the local kernel that are not tagged with a priority code receive the
     default facility LOG_KERN and priority LOG_NOTICE.  All other untagged messages receive the default facility LOG_USER and priority
     LOG_NOTICE.

FILES

     /etc/syslog.conf	   The configuration file.
     /var/run/syslogd.pid  The process id of current syslogd.
     /var/run/log	   Name of the UNIX domain datagram log socket.
     /dev/klog		   The kernel log device.

SEE ALSO

     logger(1), syslog(3), services(5), syslog.conf(5), newsyslog(8)

     The BSD syslog Protocol, RFC, 3164, August 2001.

     The Syslog Protocol, RFC, 5424, March 2009.

HISTORY

     The syslogd command appeared in 4.3BSD.  Support for multiple log sockets appeared in NetBSD 1.4.	libwrap support appeared in NetBSD 1.6.

BSD
								 October 15, 2009							       BSD