From owner-freebsd-ipfw@FreeBSD.ORG Tue Jul 7 07:19:52 2009 Return-Path: Delivered-To: freebsd-ipfw@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 924DD106564A for ; Tue, 7 Jul 2009 07:19:52 +0000 (UTC) (envelope-from kim.attree@playsafesa.com) Received: from exchange.playsafesa.com (exchange.playsafesa.com [196.212.35.153]) by mx1.freebsd.org (Postfix) with ESMTP id A7E7A8FC08 for ; Tue, 7 Jul 2009 07:19:51 +0000 (UTC) (envelope-from kim.attree@playsafesa.com) Received: from server-02.playsafesa.com ([10.0.15.253]) by server-02.playsafesa.com ([10.0.15.253]) with mapi; Tue, 7 Jul 2009 09:20:31 +0200 From: Kim Attree To: Giuliano Gavazzi Date: Tue, 7 Jul 2009 09:20:30 +0200 Thread-Topic: Problem with source based policy routing Thread-Index: Acn+Wm0Pl0An4RoqSXiWdQpkSNu6oQAeNZHQ Message-ID: <00265389C30B444288C246DF37651D0C37698F395A@server-02.playsafesa.com> References: <00265389C30B444288C246DF37651D0C37637A1893@server-02.playsafesa.com> <00265389C30B444288C246DF37651D0C37698F3933@server-02.playsafesa.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: "freebsd-ipfw@freebsd.org" Subject: RE: Problem with source based policy routing X-BeenThere: freebsd-ipfw@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: IPFW Technical Discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Jul 2009 07:19:52 -0000 > -----Original Message----- > From: Giuliano Gavazzi [mailto:dev+lists@humph.com] > Sent: 06 July 2009 06:54 PM > To: Kim Attree > Cc: freebsd-ipfw@freebsd.org > Subject: Re: Problem with source based policy routing >=20 >=20 > On M 6 Jul, 2009, at 15:35 , Kim Attree wrote: >=20 > > I have one Internal Exchange server (don't laugh), and NAT handles > > the static mapping of IP/Port to that server. The original point > > here is to have two mapped NAT port 25's to the same internal Mail > > server, hence the addition of the NAT before and during the forward > > logic (obviously wrong though). > > >=20 >=20 > ah, if you want to have an internal server to be reachable on both > public addresses, via the corresponding two firewall interfaces, you > must have a way to tell the firewall how to distinguish the return > packets in order to use the correct natd instance. If the internal > exchange server port is the same, there is no way telling that. At > most you could use the peer port, but even that would not be > failproof, and I would not know how to proceed (I think dynamic rules > can only establish holes - allow action - in the firewall, not a fwd > action). So you must use two different ports or alias addresses on the > exchange server, and divert to the appropriate outgoing natd instance > on the basis of that. >=20 > I have not enough time at the moment to write down a complete > workflow, but I hope this, with the remarks in my previous post, gives > you enough hints. It has, I realised that the return traffic needs differing source IP's - I'= ve added another IP and SMTP Connector to exchange and will test the theory= out today. >=20 > Giuliano Thanks, Kim