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SYSLOG.CONF(5)

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NAME    [Toc]    [Back]

       syslog.conf - syslogd(8) configuration file

DESCRIPTION    [Toc]    [Back]

       The  syslog.conf file is the main configuration file for the syslogd(8)
       which logs system messages on *nix systems.  This file specifies  rules
       for logging.  For special features see the sysklogd(8) manpage.

       Every  rule  consists  of  two  fields,	a selector field and an action
       field.  These two fields are separated by one or more spaces  or  tabs.
       The  selector  field  specifies	a pattern of facilities and priorities
       belonging to the specified action.

       Lines starting with a hash mark (``#'') and empty lines are ignored.

       This release of syslogd is able to understand an extended syntax.   One
       rule  can  be  divided into several lines if the leading line is terminated
 with an backslash (``\'').

SELECTORS    [Toc]    [Back]

       The selector field itself again consists of two parts, a facility and a
       priority,  separated by a period (``.'').  Both parts are case insensitive
 and can also be specified as decimal numbers, but don't  do  that,
       you  have been warned.  Both facilities and priorities are described in
       syslog(3).   The  names	mentioned  below  correspond  to  the  similar
       LOG_-values in /usr/include/syslog.h.

       The  facility  is  one of the following keywords: auth, authpriv, cron,
       daemon, ftp, kern, lpr, mail, mark, news, security (same as auth), sys-
       log, user, uucp and local0 through local7.  The keyword security should
       not be used anymore and mark is only for  internal  use	and  therefore
       should  not  be	used in applications.  Anyway, you may want to specify
       and redirect these messages here.  The facility specifies the subsystem
       that  produced  the  message,  i.e. all mail programs log with the mail
       facility (LOG_MAIL) if they log using syslog.

       The priority is one of the  following  keywords,  in  ascending	order:
       debug,  info, notice, warning, warn (same as warning), err, error (same
       as err), crit, alert, emerg,  panic  (same  as  emerg).	 The  keywords
       error,  warn  and  panic are deprecated and should not be used anymore.
       The priority defines the severity of the message

       The behavior of the original BSD syslogd is that all  messages  of  the
       specified priority and higher are logged according to the given action.
       This syslogd(8) behaves the same, but has some extensions.

       In addition to the above mentioned names the syslogd(8) understands the
       following  extensions: An asterisk (``*'') stands for all facilities or
       all priorities, depending on where it is  used  (before	or  after  the
       period).   The  keyword none stands for no priority of the given facility.


       You can specify multiple facilities with the same priority  pattern  in
       one  statement  using  the  comma (``,'') operator.  You may specify as
       much facilities as you want.  Remember that only the facility part from
       such a statement is taken, a priority part would be skipped.

       Multiple selectors may be specified for a single action using the semicolon
 (``;'') separator.  Remember that each selector in  the  selector
       field  is capable to overwrite the preceding ones.  Using this behavior
       you can exclude some priorities from the pattern.

       This syslogd(8) has a syntax extension to the original BSD source, that
       makes its use more intuitively.	You may precede every priority with an
       equation sign (``='') to specify only this single priority and not  any
       of  the	above.	You may also (both is valid, too) precede the priority
       with an exclamation mark (``!'') to ignore all that priorities,	either
       exact this one or this and any higher priority.	If you use both extensions
 than the exclamation mark must occur before  the  equation  sign,
       just use it intuitively.

ACTIONS    [Toc]    [Back]

       The  action field of a rule describes the abstract term ``logfile''.  A
       ``logfile'' need not to be a real file, btw.  The  syslogd(8)  provides
       the following actions.


   Regular File    [Toc]    [Back]
       Typically messages are logged to real files.  The file has to be specified
 with full pathname, beginning with a slash ``/''.

       You may prefix each entry with the minus ``-'' sign to omit syncing the
       file  after every logging.  Note that you might lose information if the
       system crashes right behind a write attempt.  Nevertheless  this  might
       give you back some performance, especially if you run programs that use
       logging in a very verbose manner.


   Named Pipes    [Toc]    [Back]
       This version of syslogd(8) has support for  logging  output   to  named
       pipes  (fifos).	 A fifo or named pipe can be used as a destination for
       log messages by prepending a pipe symbol (``|'') to  the  name  of  the
       file.  This is handy for debugging.  Note that the fifo must be created
       with the mkfifo(1) command  before syslogd(8) is started.


   Terminal and Console    [Toc]    [Back]
       If the file you specified is a tty, special tty-handling is done,  same
       with /dev/console.


   Remote Machine    [Toc]    [Back]
       This syslogd(8) provides full remote logging, i.e. is able to send messages
 to a remote host running syslogd(8) and to receive messages  from
       remote hosts.  The remote host won't forward the message again, it will
       just log them locally.  To forward messages to  another	host,  prepend
       the hostname with the at sign (``@'').

       Using  this  feature  you're able to control all syslog messages on one
       host, if all other machines will log remotely to that.  This tears down
       administration needs.


   List of Users    [Toc]    [Back]
       Usually	critical  messages  are  also  directed  to  ``root''  on that
       machine.  You can specify a list of users that shall get the message by
       simply  writing the login.  You may specify more than one user by separating
 them with commas (``,'').  If they're logged  in	they  get  the
       message.  Don't think a mail would be sent, that might be too late.


   Everyone logged on    [Toc]    [Back]
       Emergency  messages  often  go  to all users currently online to notify
       them that something strange is happening with the system.   To  specify
       this wall(1)-feature use an asterisk (``*'').

EXAMPLES    [Toc]    [Back]

       Here  are  some	example, partially taken from a real existing site and
       configuration.  Hopefully they rub out all questions to the  configuration,
 if not, drop me (Joey) a line.

	      # Store critical stuff in critical
	      #
	      *.=crit;kern.none 	   /var/adm/critical

       This  will  store  all  messages  with  the  priority  crit in the file
       /var/adm/critical, except for any kernel message.


	      # Kernel messages are first, stored in the kernel
	      # file, critical messages and higher ones also go
	      # to another host and to the console
	      #
	      kern.*			   /var/adm/kernel
	      kern.crit 		   @finlandia
	      kern.crit 		   /dev/console
	      kern.info;kern.!err	   /var/adm/kernel-info

       The first rule direct any message that has the kernel facility  to  the
       file /var/adm/kernel.

       The  second  statement directs all kernel messages of the priority crit
       and higher to the remote host finlandia.  This is  useful,  because  if
       the  host crashes and the disks get irreparable errors you might not be
       able to read the stored messages.  If they're on a  remote  host,  too,
       you still can try to find out the reason for the crash.

       The  third  rule  directs  these messages to the actual console, so the
       person who works on the machine will get them, too.

       The fourth line tells the syslogd to save all kernel messages that come
       with  priorities  from  info up to warning in the file /var/adm/kernel-
       info.  Everything from err and higher is excluded.


	      # The tcp wrapper loggs with mail.info, we display
	      # all the connections on tty12
	      #
	      mail.=info		   /dev/tty12

       This directs all messages that uses mail.info  (in  source  LOG_MAIL  |
       LOG_INFO)  to /dev/tty12, the 12th console.  For example the tcpwrapper
       tcpd(8) uses this as it's default.


	      # Store all mail concerning stuff in a file
	      #
	      mail.*;mail.!=info	   /var/adm/mail

       This pattern matches all messages that come  with  the  mail  facility,
       except  for  the  info  priority.   These  will	be  stored in the file
       /var/adm/mail.


	      # Log all mail.info and news.info messages to info
	      #
	      mail,news.=info		   /var/adm/info

       This will extract all messages that come either with mail.info or  with
       news.info and store them in the file /var/adm/info.


	      # Log info and notice messages to messages file
	      #
	      *.=info;*.=notice;\
		   mail.none  /var/log/messages

       This  lets  the syslogd log all messages that come with either the info
       or the notice priority into the file /var/log/messages, except for  all
       messages that use the mail facility.


	      # Log info messages to messages file
	      #
	      *.=info;\
		   mail,news.none	/var/log/messages

       This  statement	causes	the syslogd to log all messages that come with
       the info priority to the file /var/log/messages.  But any message  coming
 either with the mail or the news facility will not be stored.


	      # Emergency messages will be displayed using wall
	      #
	      *.=emerg			   *

       This rule tells the syslogd to write all emergency messages to all currently
 logged in users.	This is the wall action.


	      # Messages of the priority alert will be directed
	      # to the operator
	      #
	      *.alert			   root,joey

       This rule directs all messages with a priority of alert	or  higher  to
       the  terminals of the operator, i.e. of the users ``root'' and ``joey''
       if they're logged in.


	      *.*			   @finlandia

       This rule would redirect all messages to a remote host  called  finlandia.
  This is useful especially in a cluster of machines where all syslog
 messages will be stored on only one machine.

CONFIGURATION FILE SYNTAX DIFFERENCES    [Toc]    [Back]

       Syslogd uses a slightly different syntax  for  its  configuration  file
       than  the  original BSD sources.  Originally all messages of a specific
       priority and above were forwarded  to  the  log	file.	The  modifiers
       ``='',  ``!''   and  ``-'' were added to make the syslogd more flexible
       and to use it in a more intuitive manner.

       The original  BSD  syslogd  doesn't  understand	spaces	as  separators
       between the selector and the action field.

FILES    [Toc]    [Back]

       /etc/syslog.conf
	      Configuration file for syslogd

BUGS    [Toc]    [Back]

       The  effects  of  multiple  selectors are sometimes not intuitive.  For
       example ``mail.crit,*.err'' will select ``mail'' facility  messages  at
       the level of ``err'' or higher, not at the level of ``crit'' or higher.

SEE ALSO    [Toc]    [Back]

      
      
       sysklogd(8), klogd(8), logger(1), syslog(2), syslog(3)

AUTHORS    [Toc]    [Back]

       The syslogd is taken from BSD sources, Greg Wettstein (greg@wind.enjellic.com)
  performed  the  port to Linux, Martin Schulze (joey@linux.de)
       made some bugfixes and added some new features.



Version 1.3			1 January 1998			SYSLOG.CONF(5)
[ Back ]
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