RE: [llug-users] Fwd: MAC / IP conflict

["Wael Ghandour" <waelghandour@msn.com>]

Jad,

Giving more details about your network topology (switched vs. non-switched, 
segmentation, e.t.c) would be useful. As a primer, I suggest looking into 
arpwatch, setting major arp-entries (such as your gateway address) as 
static, as well as investigating the use of ettercap. If the switches your 
provider is using on his LAN are manageable, nabbing the culprit will be a 
piece of cake.

Good luck.

Wael

>From: Jad Saklawi <saki@mail.portland.co.uk>
>Reply-To: Jad Saklawi <jad@saklawi.info>
>To: linux-kernel@vger.kernel.org
>CC: hisham@hisham.cc,  llug-users@greencedars.org
>Subject: [llug-users] Fwd: MAC / IP conflict
>Date: Sun, 21 Mar 2004 07:09:47 +0200
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>----- Forwarded message from Hisham Mardam Bey -----
>    Date: Sun, 21 Mar 2004 13:52:59 +0200
>
>In short, I need to detect when someone on the network uses my MAC and
>my IP address.
>
>Longer story follows. I am on a LAN which might have some potentially
>dangerous users. Those users might spoof my MAC address and additionally
>use my IP address, thus forcing my box to go offline, and not be able to
>communicate with my gateway. What I need is a passive way to check for
>something of the sort, and perhaps a notofication into syslog (the
>latter is not very important).
>
>
>
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