Re: NAT on stateless firewall ?

[Martijn Lievaart <m@rtij.nl>]

Florin Andrei wrote:
> Florin Andrei wrote:
>> Grant Taylor wrote:
>>>
>>> Dare I ask why you are wanting to use Proxy ARP?
>>
>> Well, it's required by DNAT, isn't it?
>
> I take that back. I figured it out.
>
> I actually tested the idea yesterday, but it failed because one of the 
> test machines was not configured properly.
>
> 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.
>
> ip address add XXX.YYY.ZZZ.KKK dev eth0
>
> where XXX.YYY... is the public IP address that corresponds to the 
> private IP address of a server behind the firewall.
>
> It's not even necessary to play with proxy_arp in /proc. Just the IP 
> alias and DNAT.
>


I think you could even get away with just creating a static arp entry.

M4