usr/src/usr.sbin/syslogd/syslogd.8

.\" Copyright (c) 1983 Regents of the University of California.
.\" All rights reserved.  The Berkeley software License Agreement
.\" specifies the terms and conditions for redistribution.
.\"
.\"     @(#)syslogd.8   6.2 (Berkeley) %G%
.TH SYSLOGD 8 ""
.UC 5
.SH NAME
syslogd \- log systems messages
.SH SYNOPSIS
.B /etc/syslogd
[
.BI \-f configfile
] [
.B \-d
]
.SH DESCRIPTION
.I Syslogd
reads and logs messages into a set of files
described by the configuration file
/etc/syslog.conf.
Each message is one line.
A message can contain a priority code,
marked by a number in angle braces
at the beginning of the line.
Priorities are defined in
.RI < syslog.h >.
.I Syslogd
reads from the UNIX domain socket
.IR /dev/log ,
from an Internet domain socket specified in
.IR /etc/services ,
and from the special device
.I /dev/klog
(to read kernel messages).
.PP
.I Syslogd
configures when it starts up
and whenever it receives a hangup signal.
Lines in the configuration file have a
.I selector
to determine the message priorities to which the line applies
and an
.IR action .
.PP
Selectors are semicolon separated lists of priority specifiers.
Each priority has a
.I facility
describing the part of the system that generated the message,
a dot,
and a
.I level
indicating the severity of the message.
Symbolic names may be used.
An asterisk selects all facilities.
All messages of the specified level or higher
are selected.
More than one facility may be selected using commas to separate them.
For example:
.PP
.ti +5
*.emerg;mail,daemon.crit
.PP
Selects all facilities at the
.I emerg
level and the
.I mail
and
.I daemon
facilities at the
.I crit
level.
Known facilities and levels are described in
.IR syslog (3).
.PP
The second part of each line describes where the message is to be logged
if this line is selected.
There are four forms:
.IP \(bu 3n
A filename (beginning with a leading slash).
The file will be opened in append mode.
.IP \(bu 3n
A hostname preceeded by an at sign (``@'').
Selected messages are forwarded to the
.I syslogd
on the named host.
.IP \(bu 3n
A comma separated list of users.
Selected messages are written to those users
if they are logged in.
.IP \(bu 3n
An asterisk.
Selected messages are written to all logged-in users.
.PP
For example, the configuration file:
.nf

.ta 4m +\w'*.alert,auth.warning'u+3
        kern.debug      /dev/console
        *.notice,mail.info      /usr/spool/adm/syslog
        *.crit  /usr/adm/critical
        kern.err        @ucbarpa
        *.emerg *
        *.alert eric,kridle
        *.alert,auth.warning    ralph

.fi
logs all kernel messages onto the system console,
all notice (or higher) level messages and all mail system messages
except debug messages
into the file /usr/spool/adm/syslog,
and all critical messages
into /usr/adm/critical;
kernel messages of error severity or higher are forwarded
to ucbarpa.
All users will be informed of any emergency messages,
the users ``eric'' and ``kridle''
will be informed of any alert messages,
and the user ``ralph''
will be informed of any alert message,
or any warning message (or higher)
from the authorization system.
.PP
The flags are:
.TP 0.5i
.B \-f
Specify an alternate configuration file.
.TP
.B \-d
Turn on debugging.
.PP
.I Syslogd
creates the file /etc/syslog.pid, if possible,
containing a single line with its process id.
This can be used to kill or reconfigure
.I syslogd.
.PP
To bring
.I syslogd
down,
it should be sent a terminate signal (e.g. kill \`cat /etc/syslog.pid\`).
.SH FILES
.ta \w'/etc/syslog.conf    'u
.nf
/etc/syslog.conf        the configuration file
/etc/syslog.pid the process id
/dev/log        Name of the UNIX domain datagram log socket
/dev/klog       The kernel log device
.fi
.SH SEE ALSO
logger(1),
syslog(3)