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

     newsyslog -- maintain system log files to manageable sizes

     newsyslog [-CFnrsv] [-R tagname] [-a directory] [-f config_file]
	       [file ...]

     The newsyslog utility should be scheduled to run periodically by cron(8).
     When it is	executed it archives log files if necessary.  If a log file is
     determined	to require archiving, newsyslog	rearranges the files so	that
     "logfile" is empty, "logfile.0" has the last period's logs	in it,
     "logfile.1" has the next to last period's logs in it, and so on, up to a
     user-specified number of archived logs.  Optionally the archived logs can
     be	compressed to save space.

     A log can be archived for three reasons:

	   1.	It is larger than the configured size (in kilobytes).

	   2.	A configured number of hours have elapsed since	the log	was
		last archived.

	   3.	This is	the specific configured	hour for rotation of the log.

     The granularity of	newsyslog is dependent on how often it is scheduled to
     run by cron(8).  Since the	program	is quite fast, it may be scheduled to
     run every hour without any	ill effects, and mode three (above) assumes
     that this is so.

     When starting up, newsyslog reads in a configuration file to determine
     which logs	may potentially	be archived.  By default, this configuration
     file is /etc/newsyslog.conf.  Each	line of	the file contains information
     about a particular	log file that should be	handled	by newsyslog.  Each
     line has five mandatory fields and	four optional fields, with whitespace
     separating	each field.  Blank lines or lines beginning with ``#'' are ig-
     nored.  If	``#'' is placed	in the middle of the line, ``#'' character and
     the rest of the line after	it is ignored.	To prevent special meaning,
     the ``#'' may be escaped with ``\'', in this case preceding ``\'' is re-
     moved and ``#'' treated as	ordinary character.  The fields	of the config-
     uration file are as follows:

	     Name of the system	log file to be archived, or the	literal	string
	     ``<default>''.  The special default entry will be only be used if
	     some log file name	is given as a command line argument on the
	     newsyslog command,	and if that log	file name is not matched by
	     any other line in the configuration file.

	     This optional field specifies the owner and group for the archive
	     file.  The	":" is essential, even if the owner or group field is
	     left blank.  The field may	be numeric, or a name which is present
	     in	/etc/passwd or /etc/group.

     mode    Specify the mode of the log file and archives.

     count   Specify the number	of archive files to be kept besides the	log
	     file itself.

     size    When the size of the log file reaches size	in kilobytes, the log
	     file will be trimmed as described above.  If this field is	re-
	     placed by an asterisk (`*'), then the size	of the log file	is not
	     taken into	account	when determining when to trim the log file.

     when    The when field can	consist	of an interval,	a specific time, or
	     both.  If the when	field is an asterisk (`*') log rotation	will
	     depend only on the	contents of the	size field.  Otherwise,	the
	     when field	consists of an optional	interval in hours, optionally
	     followed by an `@'-sign and a time	in a restricted	ISO 8601 for-
	     mat or by an `$'-sign and a time specification for	logfile	rota-
	     tion at a fixed time once per day,	per week or per	month.

	     If	a time is specified, the log file will only be trimmed if
	     newsyslog is run within one hour of the specified time.  If an
	     interval is specified, the	log file will be trimmed if that many
	     hours have	passed since the last rotation.	 When both a time and
	     an	interval are specified,	both conditions	must be	satisfied for
	     the rotation to take place.

	     There is no provision for specification of	a timezone.  There is
	     little point in specifying	an explicit minutes or seconds compo-
	     nent in the current implementation, since the only	comparison is
	     `within the hour'.

	     ISO 8601 restricted time format

	     The lead-in character for a restricted ISO	8601 time is an
	     `@'-sign.	The particular format of the time in restricted	ISO
	     8601 is: [[[[[cc]yy]mm]dd][T[hh[mm[ss]]]]].  Optional date	fields
	     default to	the appropriate	component of the current date; op-
	     tional time fields	default	to midnight; hence if today is January
	     22, 1999, the following date specifications are all equivalent:


	     Day, week and month time format

	     The lead-in character for day, week and month specification is a
	     `$'-sign.	The particular format of day, week and month specifi-
	     cation is:	[Dhh], [Ww[Dhh]] and [Mdd[Dhh]]	respectively.  Op-
	     tional time fields	default	to midnight.  The ranges for day and
	     hour specifications are:

		   hh	   hours, range	0 ... 23
		   w	   day of week,	range 0	... 6, 0 = Sunday
		   dd	   day of month, range 1 ... 31, or the	letter L or l
			   to specify the last day of the month.

	     Some examples:

		   $D0	   rotate every	night at midnight (same	as @T00)
		   $D23	   rotate every	day at 23:00 hr	(same as @T23)
		   $W0D23  rotate every	week on	Sunday at 23:00	hr
		   $W5D16  rotate every	week on	Friday at 16:00	hr
		   $M1D0   rotate at the first day of every month at midnight
			   (i.e., the start of the day;	same as	@01T00)
		   $M5D6   rotate on every 5th day of month at 6:00 hr (same
			   as @05T06)

     flags   This optional field is made up of one or more characters that
	     specify any special processing to be done for the log files
	     matched by	this line.  The	following are valid flags:

	     B	     indicates that the	log file is a binary file, or has some
		     special format.  Usually newsyslog	inserts	an ASCII mes-
		     sage into a log file when rotating	the file, to indicate
		     when and sometimes	why the	log file was rotated.  If B is
		     specified,	then that informational	message	will not be
		     inserted into the log file.

	     C	     indicates that the	log file should	be created if it does
		     not already exist,	and if the -C option was also speci-
		     fied on the command line.

	     G	     indicates that the	specified logfile_name is a shell pat-
		     tern, and that newsyslog should archive all filenames
		     matching that pattern, using the other options specified
		     on	this line.  See	glob(3)	for details on syntax and
		     matching rules.

	     J	     indicates that newsyslog should attempt to	save disk
		     space by compressing the rotated log file using bzip2(1).

	     N	     indicates that there is no	process	which needs to be sig-
		     nalled when this log file is rotated.

	     U	     indicates that the	file specified by path_to_pid_file
		     will contain the id for a process group, instead of a
		     process.  This option also	requires that the first	line
		     in	that file must be a negative value, to distinguish it
		     from a value for a	process	id.

	     W	     if	used with the Z	or J flag, this	indicates that
		     newsyslog should wait for previously started compression
		     jobs to complete before starting a	new one	for this en-
		     try.  If this is used with	the G flag, and	if multiple
		     log files match the given pattern,	then newsyslog will
		     compress those logs one by	one.  This ensures that	only
		     one compression job is running at a time.

	     Z	     indicates that newsyslog should attempt to	save disk
		     space by compressing the rotated log file using gzip(1).

	     -	     a minus sign will not cause any special processing, but
		     it	can be used as a placeholder to	create a flags field
		     when you need to specify any of the following fields.

	     This optional field specifies the file name to read to find the
	     daemon process id,	or to find a process group id if the U flag
	     was specified.  If	this field is present, a signal_number is sent
	     the process id contained in this file.  If	this field is not
	     present, then a SIGHUP signal will	be sent	to syslogd(8), unless
	     the N flag	has been specified.  This field	must start with	"/" in
	     order to be recognized properly.

	     This optional field specifies the signal number that will be sent
	     to	the daemon process (or to all processes	in a process group, if
	     the U flag	was specified).	 If this field is not present, then a
	     SIGHUP signal will	be sent.

     The following options can be used with newsyslog:

     -f	config_file
	     Instruct newsyslog	to use config_file instead of
	     /etc/newsyslog.conf for its configuration file.

     -a	directory
	     Specify a directory into which archived log files will be writ-
	     ten.  If a	relative path is given,	it is appended to the path of
	     each log file and the resulting path is used as the directory
	     into which	the archived log for that log file will	be written.
	     If	an absolute path is given, all archived	logs are written into
	     the given directory.  If any component of the path	directory does
	     not exist,	it will	be created when	newsyslog is run.

     -v	     Place newsyslog in	verbose	mode.  In this mode it will print out
	     each log and its reasons for either trimming that log or skipping

     -n	     Cause newsyslog not to trim the logs, but to print	out what it
	     would do if this option were not specified.

     -r	     Remove the	restriction that newsyslog must	be running as root.
	     Of	course,	newsyslog will not be able to send a HUP signal	to
	     syslogd(8)	so this	option should only be used in debugging.

     -s	     Specify that newsyslog should not send any	signals	to any daemon
	     processes that it would normally signal when rotating a log file.
	     For any log file which is rotated,	this option will usually also
	     mean the rotated log file will not	be compressed if there is a
	     daemon which would	have been signalled without this option.  How-
	     ever, this	option is most likely to be useful when	specified with
	     the -R option, and	in that	case the compression will be done.

     -C	     If	specified once,	then newsyslog will create any log files which
	     do	not exist, and which have the C	flag specified in their	config
	     file entry.  If specified multiple	times, then newsyslog will
	     create all	log files which	do not already exist.  If log files
	     are given on the command-line, then the -C	or -CC will only apply
	     to	those specific log files.

     -F	     Force newsyslog to	trim the logs, even if the trim	conditions
	     have not been met.	 This option is	useful for diagnosing system
	     problems by providing you with fresh logs that contain only the

     -R	tagname
	     Specify that newsyslog should rotate a given list of files, even
	     if	trim conditions	are not	met for	those files.  The tagname is
	     only used in the messages written to the log files	which are ro-
	     tated.  This differs from the -F option in	that one or more log
	     files must	also be	specified, so that newsyslog will only operate
	     on	those specific files.  This option is mainly intended for the
	     daemons or	programs which write some log files, and want to trig-
	     ger a rotate based	on their own criteria.	With this option they
	     can execute newsyslog to trigger the rotate when they want	it to
	     happen, and still give the	system administrator a way to specify
	     the rules of rotation (such as how	many backup copies are kept,
	     and what kind of compression is done).  When a daemon does	exe-
	     cute newsyslog with the -R	option,	it should make sure all	of the
	     log files are closed before calling newsyslog, and	then it	should
	     re-open the files after newsyslog returns.	 Usually the calling
	     process will also want to specify the -s option, so newsyslog
	     will not send a signal to the very	process	which called it	to
	     force the rotate.	Skipping the signal step will also mean	that
	     newsyslog will return faster, since newsyslog normally waits a
	     few seconds after any signal that is sent.

     If	additional command line	arguments are given, newsyslog will only exam-
     ine log files that	match those arguments; otherwise, it will examine all
     files listed in the configuration file.

     /etc/newsyslog.conf      newsyslog	configuration file

     Doesn't yet automatically read the	logs to	find security breaches.

     Theodore Ts'o, MIT	Project	Athena

     Copyright 1987, Massachusetts Institute of	Technology

     Previous versions of the newsyslog	utility	used the dot (``.'') character
     to	distinguish the	group name.  Beginning with FreeBSD 3.3, this has been
     changed to	a colon	(``:'')	character so that user and group names may
     contain the dot character.	 The dot (``.'') character is still accepted
     for backwards compatibility.

     gzip(1), syslog(3), chown(8), syslogd(8)

BSD				April 27, 2003				   BSD


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