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ipmon(8)							      ipmon(8)

NAME
       ipmon - monitors	/dev/ipl for logged packets

SYNOPSIS
       ipmon [ -abBDFhnpstvxX ]	[ -N <device> ]	[ -L <facility>	] [ -o [NSI] ]
       [ -O [NSI] ] [ -P <pidfile> ] [ -S <device> ] [ -f <device> ] [	<file-
       name> ]

DESCRIPTION
       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
       address and port. E.g.: 209.53.17.22,80 -> 198.73.220.17,1722.

       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
       flags.

       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
       unreachable 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
       details.

       ipmon reopens its log file(s) and rereads its configuration  file  when
       it receives a SIGHUP signal.

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

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

       -B <binarylogfilename>
	      Enable logging of	the raw, unformatted binary data to the	speci-
	      fied  _binarylogfilename_	 file.	This can be read, later, using
	      ipmon with the -f	option.

       -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.

       -L <facility>
	      Using this option	allows you to change the default syslog	facil-
	      ity that ipmon uses for syslog messages.	The default is local0.

       -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
	      <device>.

       -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,
	      etc.

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

DIAGNOSTICS
       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.

FILES
       /dev/ipl
       /dev/ipnat
       /dev/ipstate
       /etc/services

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

BUGS
       If you find any,	please send email to me	at darrenr@pobox.com

								      ipmon(8)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | DIAGNOSTICS | FILES | SEE ALSO | BUGS

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