Re: NAT on stateless firewall ?

[Pascal Hambourg <pascal.mail@plouf.fr.eu.org>]

Florin Andrei a écrit :
>> 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 
setups, when the source host thinks the destination host is on the same 
link but actually it is behind a router.

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

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