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Date: Fri, 10 Oct 2008 09:18:36 +0700 (ICT)
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From: Olivier Nicole <on@cs.ait.ac.th>
To: derek@computinginnovations.com
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	(message from Derek Ragona on Thu, 09 Oct 2008 07:36:49 -0500)
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Cc: freebsd-questions@freebsd.org
Subject: Re: Multiple NICs routing question
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>I've a server box with four NICs addressing different subnets:
>
>NIC1:   one class c subnet of same class b network
>NIC2:   another class c subnet of same class b network
>NIC3:   local unrouted network
>NIC4:   local unrouted network
>
>In the current configuration I use a default gateway (and no routing 
>daemon) in the subnet addressed by NIC1. Now of course, if a client in an 
>arbitrary different class c subnet contacts the server using the ip 
>address of NIC2, it gets a reply from NIC1.

You should give more details about your configuration.

If any client on the class B on NIC2 can contact your server, you must
configure the NIC for the class B.

The routing stack will take charge of excluding the class C on NIC1
from the class B on NIC2.

It's very bad that the client that connects via the NIC2 has a subnet
of class B and that the NIC2 is configured for class C only.

If you configure:

NIC1 192.168.1.1 255.255.255.0
NIC2 192.168.2.1 255.255.0.0

Client 192.168.127.23 255.255.0.0

it should work.

Olivier