Subject: Re: arp.
To: andrea <>
From: Andy V. Oleynik <>
List: tech-net
Date: 04/06/1999 11:30:37
andrea wrote:

> I have to add a gateway to my net for experimental reasons.
> Actually there are : a main-router that works as interface to the Internet,
> and some hosts on my sub net.
>         Internet-----MyRouter----MySubNet
> NOw i need to configure one host of MYSubNet to act as a gatway for the
> secondary subnet.
> Both the 1SubNet and 2 SubNEt share the same ip-range.
>      Internet-----MyRouter----MySubNet-----My2SubNet

As I understood U have smth like this :
Then U have to cut My2SubNet from ur  MySubNet and configure
routes to appropriate subnets on appropriate hosts. As long as ur 2ndsubnet
is part of ur mainsubnet  the hosts from  2ndsubnet will be seen from internet

& wise a versa. U may need to run DNS for reverse zone of ur  My2SubNet

> All the have to be seen from the Internet so I'll need to add a
> route to MainRouter in order to route the Secondary Subnet.
> The problem is that i cannot change configuration of the mainroute,so i

in fact this isnt  big problem as soon as U have properly configured
subnets:) . Correct me if I wrong.

> wonder if is possible to configure the new gateway to do a sort of "proxy
> arp" for my secondary Subnet.
> But arp-tables are system-wide so if i change arp entry to cacth request on
> PrimaryNet the 2subnet dont'works anymore.
> Is possible to catch arp request only on a single subnet,without broke any
> other subnet connected to the same host.?
> thank you!
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WBW  Andy V. Oleynik  (When U work in virtual office
                       U have good chance to obtain virtual money %-)