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Date: Mon, 17 Jul 2017 19:26:42 +0200
From: Kurt Jaeger <lists@opsec.eu>
To: Grzegorz Junka <list1@gjunka.com>
Cc: freebsd-net@freebsd.org, freebsd-jail@freebsd.org
Subject: Re: A web server behind two gateways?
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Hi!

> I have a jail running a web server in LAN. There are two routers/WANs 
> that can connect LAN to the internet. I enabled NAT and port forwarding 
> to the web server on both routers.
[...]
> Can I configure either router/host/jail so that the web server sends the 
> response back to the IP that sent the request packet rather than to the 
> default gateway?

I have a vague idea:

If you set a tag (or a keep-state :flowname) using a ipfw rule that matches
the incoming gateway MAC and match that tag/check-state flowname and
the connection (keep-state) to fwd the answer packet back to that gateway ?

-- 
pi@opsec.eu            +49 171 3101372                         3 years to go !