SYSLOGD(8)SYSLOGD(8)NAMEsyslogd - log systems messages
SYNOPSISsyslogd [ -fconfigfile ] [ -mmarkinterval ] [ -d ]
DESCRIPTION
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 prior-
ity code, marked by a number in angle braces at the begin-
ning of the line. Priorities are defined in <sys/sys-
log.h>. Syslogd reads from the UNIX domain socket
/dev/log, from an Internet domain socket specified in
/etc/services, and from the special device /dev/klog (to
read kernel messages).
Syslogd configures when it starts up and whenever it
receives a hangup signal. Lines in the configuration file
have a selector to determine the message priorities to
which the line applies and an action. The action field
are separated from the selector by one or more tabs.
Selectors are semicolon separated lists of priority speci-
fiers. Each priority has a facility describing the part
of the system that generated the message, a dot, and a
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 (greater
severity) are selected. More than one facility may be
selected using commas to separate them. For example:
*.emerg;mail,daemon.crit
Selects all facilities at the emerg level and the mail and
daemon facilities at the crit level.
Known facilities and levels recognized by syslogd are
those listed in syslog(3) without the leading ``LOG_''.
The additional facility ``mark'' has a message at priority
LOG_INFO sent to it every 20 minutes (this may be changed
with the -m flag). The ``mark'' facility is not enabled
by a facility field containing an asterisk. The level
``none'' may be used to disable a particular facility.
For example,
*.debug;mail.none
Sends all messages except mail messages to the selected
file.
The second part of each line describes where the message
is to be logged if this line is selected. There are four
forms:
o A filename (beginning with a leading slash). The file
will be opened in append mode.
o A hostname preceeded by an at sign (``@''). Selected
messages are forwarded to the syslogd on the named
host.
o A comma separated list of users. Selected messages are
written to those users if they are logged in.
o An asterisk. Selected messages are written to all
logged-in users.
Blank lines and lines beginning with `#' are ignored.
For example, the configuration file:
kern,mark.debug /dev/console
*.notice;mail.info /var/log/maillog
*.crit /var/log/critical
kern.err @ucbarpa
*.emerg *
*.alert eric,kridle
*.alert;auth.warning ralph
logs all kernel messages and 20 minute marks onto the sys-
tem console, all notice (or higher) level messages and all
mail system messages except debug messages into the file
/var/log/maillog, and all critical messages into
/var/log/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.
The flags are:
-f Specify an alternate configuration file.
-m Select the number of minutes between mark messages.
-d Turn on debugging.
Syslogd creates the file /var/run/syslog.pid, if possible,
containing a single line with its process id. This can be
used to kill or reconfigure syslogd.
To bring syslogd down, it should be sent a terminate sig-
nal (e.g. kill `cat /var/run/syslog.pid`).
FILES
/etc/syslog.conf the configuration file
/var/run/syslog.pid the process id
/dev/log Name of the UNIX domain datagram log socket
/dev/klog The kernel log device
SEE ALSOlogger(1), syslog(3)
June 27, 1990 SYSLOGD(8)
