IP-MONITOR(8) Linux IP-MONITOR(8)
NAME
ip-monitor, rtmon - state monitoring
SYNOPSIS
ip 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,
stats, nsid and nexthop. If no file argument is given, ip opens RT-
NETLINK, 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 name-
spaces that have a nsid assigned into the network namespace were the
program is running. A prefix is displayed to show the network name-
space 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 con-
tain RTNETLINK messages saved in binary format. Such a file can be
generated with the rtmon utility. This utility has a command line syn-
tax 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>
iproute2 13 Dec 2012 IP-MONITOR(8)
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