ip-monitor (8) - Linux Manuals
ip-monitor: state monitoring
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, nsid and nexthop. 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
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.
AUTHOR
Original Manpage by Michail Litvak <mci [at] owl.openwall.com>
Manpage revised by Nicolas Dichtel <nicolas.dichtel [at] 6wind.com>