icmpinfo(1)
NAME
icmpinfo - interpret ICMP messages
SYNOPSIS
icmpinfo [-v[v[v]]] [-n] [-p] [-s] [-l] [-k]
DESCRIPTION
Icmpinfo 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, icmpinfo will only report on "weird" packets, mainly icmp_unreachable.
OPTIONS
- -v Give information about all icmp packets, excepts
- pings.
- -vv Give about pings too (i.e. icmp_echo_reply).
- -vvv Include an ascii/hex dump of each packet
- -n Avoid name queries - just give IP addresses. (use
- this option when running unattended on name server
hosts (to avoid possible looping)) - -p Avoid port number to service name decoding.
- -s Show the interface ip that received the packet.
- Usefull 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. - -l Forks and use the syslog(3) facility to record
- events (recomended use). (root only option).
- -k Kills the background process started with the -l
- option.
WARNINGS
The packet decoding is planned for ICMP Unreachable out
puts and might not be significant for all other Icmp
types. Output can be shorter when implied by the packet
size or the icmp type.
AUTHOR
- Laurent Demailly <dl@hplyot.obspm.fr>. Free software.