Erich.Meier at informatik.uni-erlangen.de
Mon Sep 29 14:33:00 UTC 1997
> One method to detect duplicate IPs is to use SNMP to query your routers
> every 4 hours for the ARP entries. (ARP times out every 4 hours in a cisco
> router) We use the CMU snmp package to do the queries. Then put the info
> into a database and query the database for duplicates. We have a system
> like this with a web interface and also some scripts that scan ths
> database daily for duplicates and e-mails notices to people in charge of
> the relevant subnet.
> The code is somewhat rough, so I do not want to offer it to the
> net-at-large. If you can not find a polished product, e-mail me and I'll
> share more aobut this solution.
> On Mon, 29 Sep 1997, Scott wrote:
> > Alittle off subject but does anyone out there know of some SW that detects
> > duplicate IP addresses?
> > Scott
I think you are searching for arpwatch. Source can be found at
It needs libpcap to run but that can be found also at this location.
Erich Meier Erich.Meier at informatik.uni-erlangen.de
"The truth is not out there. The truth is not out there. The.." - Bart Simpson
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