From mboxrd@z Thu Jan  1 00:00:00 1970
From: Pascal Hambourg <pascal.mail@plouf.fr.eu.org>
Subject: Re: NAT on stateless firewall ?
Date: Fri, 03 Aug 2007 21:53:01 +0200
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Florin Andrei a =E9crit :
>> Grant Taylor wrote:
>>>
>>> Dare I ask why you are wanting to use Proxy ARP?
>>
>> Well, it's required by DNAT, isn't it?

No it's not. Proxy ARP may be useful as a workaround for broken routing=20
setups, when the source host thinks the destination host is on the same=20
link but actually it is behind a router.

[...]
> To make proxy ARP work with DNAT, an IP alias must be created on the=20
> external interface, with the public IP address of the machine behind th=
e=20
> firewall.

If you do that you do not need proxy ARP.

> It's not even necessary to play with proxy_arp in /proc. Just the IP=20
> alias and DNAT.

Right. I guess another way would have been to add a route to the virtual=20
public IP addresses pool and enable proxy ARP (not tested though).