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ip-monitor(8)


NAME

   ip-monitor, rtmon - state monitoring

SYNOPSIS

   ip  [ ip-OPTIONS ] monitor [ all | OBJECT-LIST ] [ file FILENAME ] [
           label ] [ all-nsid ] [ dev DEVICE ]

OPTIONS

   -t, -timestamp
          Prints timestamp before the event message on the separated line
          in format:
              Timestamp: <Day> <Month> <DD> <hh:mm:ss> <YYYY> <usecs> usec
              <EVENT>

   -ts, -tshort
          Prints short timestamp before the event message on the same line
          in format:
              [<YYYY>-<MM>-<DD>T<hh:mm:ss>.<ms>] <EVENT>

DESCRIPTION

   The ip utility can monitor the state of devices, addresses and routes
   continuously. This option has a slightly different format.  Namely, the
   monitor command is the first in the command line and then the object
   list follows:

   ip monitor [ all | OBJECT-LIST ] [ file FILENAME ] [ label ] [ all-nsid
   ] [ dev DEVICE ]

   OBJECT-LIST is the list of object types that we want to monitor.  It
   may contain link, address, route, mroute, prefix, neigh, netconf, rule
   and nsid.  If no file argument is given, ip opens RTNETLINK, listens on
   it and dumps state changes in the format described in previous
   sections.

   If the label option is set, a prefix is displayed before each message
   to show the family of the message. For example:

     [NEIGH]10.16.0.112 dev eth0 lladdr 00:04:23:df:2f:d0 REACHABLE
     [LINK]3: eth1: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast state
     DOWN group default
         link/ether 52:54:00:12:34:57 brd ff:ff:ff:ff:ff:ff

   If the all-nsid option is set, the program listens to all network
   namespaces that have a nsid assigned into the network namespace were
   the program is running.  A prefix is displayed to show the network
   namespace where the message originates. Example:

     [nsid 0]10.16.0.112 dev eth0 lladdr 00:04:23:df:2f:d0 REACHABLE

   If the file option is given, the program does not listen on RTNETLINK,
   but opens the given file, and dumps its contents. The file should
   contain RTNETLINK messages saved in binary format.  Such a file can be
   generated with the rtmon utility. This utility has a command line
   syntax similar to ip monitor.  Ideally, rtmon should be started before
   the first network configuration command is issued. F.e. if you insert:

           rtmon file /var/log/rtmon.log

   in a startup script, you will be able to view the full history later.

   Nevertheless, it is possible to start rtmon at any time.  It prepends
   the history with the state snapshot dumped at the moment of starting.

   If the dev option is given, the program prints only events related to
   this device.

SEE ALSO

   ip(8)

AUTHOR

   Original Manpage by Michail Litvak <mci@owl.openwall.com>
   Manpage revised by Nicolas Dichtel <nicolas.dichtel@6wind.com>



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