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ipmon(8)		    System Manager's Manual		      ipmon(8)

       ipmon - monitors	/dev/ipl for logged packets

       ipmon  [	-abDFhnpstvxX ]	[ -N <device> ]	[ -o [NSI] ] [ -O [NSI]	] [ -P
       <pidfile> ] [ -S	<device> ] [ -f	<device> ] [ <filename>	]

       ipmon opens /dev/ipl for	reading	and awaits data	to be saved  from  the
       packet  filter.	 The  binary data read from the	device is reprinted in
       human readable for, however, IP#'s are not mapped  back	to  hostnames,
       nor  are	 ports mapped back to service names.  The output goes to stan-
       dard output by default or a filename, if	given  on  the	command	 line.
       Should  the  -s	option	be used, output	is instead sent	to syslogd(8).
       Messages	sent via syslog	have the day, month and	year removed from  the
       message,	but the	time (including	microseconds), as recorded in the log,
       is still	included.

       Messages	generated by ipmon consist  of	whitespace  separated  fields.
       Fields common to	all messages are:

       1.  The	date of	packet receipt.	This is	suppressed when	the message is
       sent to syslog.

       2. The time of packet receipt. This is  in  the	form  HH:MM:SS.F,  for
       hours, minutes seconds, and fractions of	a second (which	can be several
       digits long).

       3. The name of the interface the	packet was processed on, e.g., we1.

       4. The group and	rule number of the rule, e.g.,	@0:17.	These  can  be
       viewed with ipfstat -n.

       5.  The action: p for passed, b for blocked,  for a short packet, n did
       not match any rules or L	for a log rule.

       6. The addresses.  This is actually three fields:  the  source  address
       and port	(separated by a	comma),	the -> symbol, and the destination ad-
       dress and port. E.g.:,80 ->,1722.

       7. PR followed by the protocol name or number, e.g., PR tcp.

       8. len followed by the header length and	total length  of  the  packet,
       e.g., len 20 40.

       If the packet is	a TCP packet, there will be an additional field	start-
       ing with	a hyphen followed by letters corresponding to any  flags  that
       were set.  See the ipf.conf manual page for a list of letters and their

       If the packet is	an ICMP	packet,	there will be two fields at  the  end,
       the  first always being `icmp', and the next being the ICMP message and
       submessage type,	separated by a slash, e.g., icmp 3/3 for  a  port  un-
       reachable message.

       In  order  for  ipmon  to properly work,	the kernel option IPFILTER_LOG
       must be turned on in your kernel.  Please see options(4)	for  more  de-

       -a     Open  all	 of  the device	logfiles for reading log entries from.
	      All entries are displayed	to the same output 'device' (stderr or

       -b     For  rules  which	 log the body of a packet, generate hex	output
	      representing the packet contents after the headers.

       -D     Cause ipmon to turn itself into a	daemon.	  Using	 subshells  or
	      backgrounding of ipmon is	not required to	turn it	into an	orphan
	      so it can	run indefinitely.

       -f <device>
	      specify an alternative device/file from which to	read  the  log
	      information for normal IP	Filter log records.

       -F     Flush  the  current  packet  log	buffer.	  The  number of bytes
	      flushed is displayed, even should	the result be zero.

       -n     IP addresses and port numbers will be  mapped,  where  possible,
	      back into	hostnames and service names.

       -N <device>
	      Set the logfile to be opened for reading NAT log records from to

       -o     Specify which log	files to actually read data  from.   N	-  NAT
	      logfile,	S  - State logfile, I -	normal IP Filter logfile.  The
	      -a option	is equivalent to using -o NSI.

       -O     Specify which log	files you do not wish to read from.   This  is
	      most sensibly used with the -a.  Letters available as parameters
	      to this are the same as for -o.

       -p     Cause the	port number in log messages to always be printed as  a
	      number  and  never  attempt to look it up	as from	/etc/services,

       -P <pidfile>
	      Write the	pid of the ipmon process to a file.  By	 default  this
	      is  //etc/opt/ipf/ (Solaris), /var/run/	(44BSD
	      or later)	or /etc/ for all others.

       -s     Packet information read in will be sent through  syslogd	rather
	      than  saved  to  a file.	The default facility when compiled and
	      installed	is security.  The following levels are used:

	      LOG_INFO - packets logged	using the "log"	keyword	as the	action
	      rather than pass or block.

	      LOG_NOTICE - packets logged which	are also passed

	      LOG_WARNING - packets logged which are also blocked

	      LOG_ERR  -  packets which	have been logged and which can be con-
	      sidered "short".

       -S <device>
	      Set the logfile to be opened for reading state log records  from
	      to <device>.

       -t     read the input file/device in a manner akin to tail(1).

       -v     show tcp window, ack and sequence	fields.

       -x     show the packet data in hex.

       -X     show the log header record data in hex.

       ipmon expects data that it reads	to be consistent with how it should be
       saved and will abort if it fails	an assertion which detects an  anomaly
       in the recorded data.


       ipl(4), ipf(8), ipfstat(8), ipnat(8)

       If you find any,	please send email to me	at



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