Section: Maintenance Commands (8) Updated: V1.11 - 28 August 1995 Local index
icmpinfo - interpret ICMP messages
[-v[v[v]]] [-n] [-p] [-s] [-l] [-k]
is a tool for looking at the ICMP messages received
on the running host.
It can be used to detect and record 'bombs'
as well as various network problems.
The output format is as follows (all on one line):
MMM DD HH:MM:SS ICMP_type[sub-type]
< sender_ip [sender_name] > unreach_ip [unreach_name]
sp=source_port dp=dest_port seq=sequence sz=packet_size
In normal operation,
will only report on "weird" packets, mainly icmp_unreachable.
Give information about all icmp packets, excepts pings.
Give about pings too (i.e. icmp_echo_reply).
Include an ascii/hex dump of each packet
Avoid name queries - just give IP addresses.
(use this option when running unattended on name server hosts (to avoid
Avoid port number to service name decoding.
Show the interface ip that received the packet. Useful only if your
host has several network interfaces. In this case an '- my_ip
[my_name]' is added between the sender and unreach ip and name fields.
Forks and use the syslog(3) facility to record events (recommended use).
(root only option).
Kills the background process started with the
The packet decoding is planned for ICMP Unreachable outputs and might
not be significant for all other Icmp types. Output can be shorter
when implied by the packet size or the icmp type.
Laurent Demailly <firstname.lastname@example.org>. Free software.
This document was created by
using the manual pages.
Time: 22:01:46 GMT, April 16, 2011