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ipmon(8)                                                              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, S for a short packet, n did
       not match any rules, L for a log rule.   The  order  of  precedence  in
       showing  flags  is:  S,  p,  b,  n, L.  A capital P or B means that the
       packet has been logged due to a global logging setting, not a  particu-
       lar 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.:,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
       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

       -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 afte 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 indefinately.

       -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 local0.  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)



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