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syslogd(8)

SYNOPSIS

     syslogd [-46Acdknosuv] [-a allowed_peer] [-b bind_address]
	     [-f config_file] [-l [mode:]path] [-m mark_interval]
	     [-P pid_file] [-p log_socket]

DESCRIPTION

     The syslogd utility 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:

     -4      Force syslogd to use IPv4 addresses only.

     -6      Force syslogd to use IPv6 addresses only.

     -A      Ordinarily, syslogd tries to send the message to only one address
	     even if the host has more than one A or AAAA record.  If this
	     option is specified, syslogd tries to send the message to all
	     addresses.

     -a allowed_peer
	     Allow allowed_peer to log to this syslogd using UDP datagrams.
	     Multiple -a options may be specified.

	     Allowed_peer can be any of the following:

	     ipaddr/masklen[:service]	 Accept datagrams from ipaddr (in the
					 usual dotted quad notation) with
					 masklen bits being taken into account
					 when doing the address comparison.
					 ipaddr can be also IPv6 address by
					 enclosing the address with `[' and
					 `]'.  If specified, service is the
					 name or number of an UDP service (see
					 services(5)) the source packet must
					 belong to.  A service of `*' allows
					 packets being sent from any UDP port.
					 The default service is `syslog'.  If
					 ipaddr is IPv4 address, a missing
					 masklen will be substituted by the
					 historic class A or class B netmasks
					 if ipaddr belongs into the address
					 range of class A or B, respectively,
					 or by 24 otherwise.  If ipaddr is
					 IPv6 address, a missing masklen will
					 be substituted by 128.

	     domainname[:service]	 Accept datagrams where the reverse
					 address lookup yields domainname for
					 the sender address.  The meaning of
					 service is as explained above.

	     *domainname[:service]	 Same as before, except that any
	     to it is used.

     -c      Disable the compression of repeated instances of the same line
	     into a single line of the form ``last message repeated N times''
	     when the output is a pipe to another program.  If specified
	     twice, disable this compression in all cases.

     -d      Put syslogd into debugging mode.  This is probably only of use to
	     developers working on syslogd.

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

     -k      Disable the translation of messages received with facility
	     ``kern'' to facility ``user''.  Usually the ``kern'' facility is
	     reserved for messages read directly from /dev/klog.

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

     -n      Disable dns query for every request.

     -o      Prefix kernel messages with the full kernel boot file as deter-
	     mined by getbootfile(3).  Without this, the kernel message prefix
	     is always ``kernel:''.

     -p      Specify the pathname of an alternate log socket to be used
	     instead; the default is /var/run/log.

     -P      Specify an alternative file in which to store the process ID.
	     The default is /var/run/syslog.pid.

     -S      Specify the pathname of an alternate log socket for privileged
	     applications to be used instead; the default is /var/run/logpriv.

     -l      Specify a location where syslogd should place an additional log
	     socket.  The primary use for this is to place additional log
	     sockets in /var/run/log of various chroot filespaces.  File per-
	     missions for socket can be specified in octal representation
	     before socket name, delimited with a colon.  Path to socket loca-
	     tion must be absolute.

     -s      Operate in secure mode.  Do not log messages from remote
	     machines.	If specified twice, no network socket will be opened
	     at all, which also disables logging to remote machines.

     -u      Unique priority logging.  Only log messages at the specified pri-
	     ority.  Without this option, messages at the stated priority or
	     higher are logged.  This option changes the default comparison
	     from ``=>'' to ``=''.

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

     The syslogd utility reads its configuration file when it starts up and
     whenever it receives a hangup signal.  For information on the format of
     /var/run/syslog.pid, and stores its process ID there.  This can be used
     to kill or reconfigure syslogd.

     The message sent to syslogd should consist of a single line.  The message
     can contain a priority code, which should be a preceding decimal number
     in angle braces, for example, `<5>'.  This priority code should map into
     the priorities defined in the include file <sys/syslog.h>.

     For security reasons, syslogd will not append to log files that do not
     exist; therefore, they must be created manually before running syslogd.

FILES

     /etc/syslog.conf	  configuration file
     /var/run/syslog.pid  default process ID file
     /var/run/log	  name of the UNIX domain datagram log socket
     /var/run/logpriv	  UNIX socket for privileged applications
     /dev/klog		  kernel log device

SEE ALSO

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

HISTORY

     The syslogd utility appeared in 4.3BSD.

     The -a, -s, -u, and -v options are FreeBSD 2.2 extensions.

BUGS

     The ability to log messages received in UDP packets is equivalent to an
     unauthenticated remote disk-filling service, and should probably be dis-
     abled by default.	Some sort of inter-syslogd authentication mechanism
     ought to be worked out.  To prevent the worst abuse, use of the -a option
     is therefore highly recommended.

     The -a matching algorithm does not pretend to be very efficient; use of
     numeric IP addresses is faster than domain name comparison.  Since the
     allowed peer list is being walked linearly, peer groups where frequent
     messages are being anticipated from should be put early into the -a list.

     The log socket was moved from /dev to ease the use of a read-only root
     file system.  This may confuse some old binaries so that a symbolic link
     might be used for a transitional period.

FreeBSD 5.4			  May 5, 2005			   FreeBSD 5.4

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