From mboxrd@z Thu Jan  1 00:00:00 1970
From: Tom Eastep <teastep@shorewall.net>
Subject: Re: Strange Problem - IPTables or Hardware related ????
Date: Mon, 21 Oct 2002 07:07:09 -0700
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To: Rodolfo Siviero Stein <rstein@persogo.com.br>
Cc: netfilter@lists.netfilter.org



Rodolfo Siviero Stein wrote:

> 
>     Anyone had a problem like this ?  Any comments ?  Is this hardware 
> related or software ?
> 

Do you have multiple NICs cabled to the same HUB/switch? In my experience, 
when people see packets arriving on unexpected interfaces, that is the 
cause. The manner in which the Linux kernel handles ARP "who-has" requests 
makes this type of configuration unsuitable for firewalling since any 
interface connected to the HUB/switch can respond to "who-has" requests 
for any of the addresses assigned to one of those NICs.

-Tom
-- 
Tom Eastep    \ Shorewall - iptables made easy
AIM: tmeastep  \ http://www.shorewall.net
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