From owner-freebsd-hackers@FreeBSD.ORG Wed Jun 11 14:22:05 2003 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 5D94437B401 for ; Wed, 11 Jun 2003 14:22:05 -0700 (PDT) Received: from deadfrog.net (deadfrog.net [206.183.9.187]) by mx1.FreeBSD.org (Postfix) with ESMTP id C660E43FA3 for ; Wed, 11 Jun 2003 14:22:03 -0700 (PDT) (envelope-from ryan@deadfrog.net) Received: from [192.168.1.10] ([192.168.1.10]) by deadfrog.net (8.11.6/8.11.6) with ESMTP id h5BLM3d26583 for ; Wed, 11 Jun 2003 17:22:03 -0400 From: Ryan Wilkins To: freebsd-hackers@freebsd.org In-Reply-To: <20030611181529.GD14100@sunbay.com> References: <1055336153.3963.26.camel@localhost.localdomain> <20030611181529.GD14100@sunbay.com> Content-Type: text/plain Organization: Deadfrog Networking Systems Message-Id: <1055366522.1169.22.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.2.2 (1.2.2-5) Date: 11 Jun 2003 17:22:03 -0400 Content-Transfer-Encoding: 7bit Subject: Re: Policy Routing / NAT Question X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 11 Jun 2003 21:22:05 -0000 Hi.. thanks for your response.. it did exactly what I needed. I tried some of the other solutions provided earlier in the day and ended up locking up a machine 340 miles away from here which is a good 6-7 hour drive from where I am currently. Thanks again, Ryan Wilkins On Wed, 2003-06-11 at 14:15, Ruslan Ermilov wrote: > On Wed, Jun 11, 2003 at 08:55:53AM -0400, Ryan Wilkins wrote: > > Hello.. > > > > I'm setting up a TCP protocol testbed for testing various enhanced TCP > > stacks for use over high bandwidth, high latency links such as > > Satellite. Due to hardware limitations of the FreeBSD boxes we're using > > (1U rackmount), there are no expansion slots left for additional network > > cards. This forces me to have to run some traffic over one gateway and > > the rest of the traffic over another gateway, all through one ethernet. > > The problem I have is I need to change the source address of some > > packets based on destination address. I was able to accomplish this in > > Linux using Source NAT. I'm not real well versed in FreeBSD hence the > > reason I'm asking for any assistance here. Does anyone have an idea how > > to change the source address based on destination address? > > > If all of these possible source addresses belong to the same interface of > the box in question (it's unclear from your message), this can be done > with route(8). For example: > > # ifconfig rl0 inet > rl0: flags=8843 mtu 1500 > inet 192.168.4.115 netmask 0xffffff00 broadcast 192.168.4.255 > inet 10.0.0.1 netmask 0xff000000 broadcast 10.255.255.255 > inet 10.0.0.2 netmask 0xffffffff broadcast 10.0.0.2 > # route add -net 11 10.0.0.3 > add net 11: gateway 10.0.0.3 > # route add -net 12 -ifa 10.0.0.2 10.0.0.4 > add net 12: gateway 10.0.0.4 > > The route to the network 12 says to use 10.0.0.2 as the source > address when sending anonymous (with unfilled source address) > datagrams. > > But if you need to change the traffic originated from other > hosts on your box, there are several NAT solutions for you. > > > Cheers, -- Ryan Wilkins Deadfrog Networking Systems