From owner-freebsd-net@FreeBSD.ORG Tue Mar 7 03:45:56 2006 Return-Path: X-Original-To: freebsd-net@freebsd.org Delivered-To: freebsd-net@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 008E316A420; Tue, 7 Mar 2006 03:45:55 +0000 (GMT) (envelope-from freebsdnik@j2d.lam.net.au) Received: from ichimail.justnet.info (ichiban.broadband.sublimeip.com [203.217.17.194]) by mx1.FreeBSD.org (Postfix) with ESMTP id C9C3643D5A; Tue, 7 Mar 2006 03:45:54 +0000 (GMT) (envelope-from freebsdnik@j2d.lam.net.au) Received: from localhost (unknown [127.0.0.1]) by ichiban-mailfilter.justnet.info (Postfix) with ESMTP id B03E96891C; Tue, 7 Mar 2006 14:45:53 +1100 (EST) Received: from ichimail.justnet.info ([127.0.0.1]) by localhost (ichiban.justnet.info [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 42635-02; Tue, 7 Mar 2006 14:45:52 +1100 (EST) Received: from [192.168.0.231] (dhcp1 [192.168.0.231]) by ichimail.justnet.info (Postfix) with ESMTP id AFE1E67F45; Tue, 7 Mar 2006 14:45:51 +1100 (EST) Message-ID: <440D01ED.1050907@j2d.lam.net.au> Date: Tue, 07 Mar 2006 14:45:49 +1100 From: Nik Lam User-Agent: Thunderbird 1.5 (Macintosh/20051201) MIME-Version: 1.0 To: Andrew Thompson References: <440CEBDE.5090602@j2d.lam.net.au> <20060307025410.GA55053@heff.fud.org.nz> In-Reply-To: <20060307025410.GA55053@heff.fud.org.nz> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: amavisd-new at ichiban.justnet.info Cc: freebsd-net@freebsd.org Subject: Re: if_bridge steals IP address of non-member interface X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 07 Mar 2006 03:45:56 -0000 Andrew Thompson wrote: > On Tue, Mar 07, 2006 at 01:11:42PM +1100, Nik Lam wrote: > >> I'm not sure if what I'm seeing is an artefact of me doing something >> unusual with my design or if there is a bug in if_bridge. >> >> I'm dividing my LAN into two parts using a pair of intel pro 1000 (em) >> interfaces in an if_bridge bridge. I've configured this bridge with STP >> (802.1d) although I don't think this should be the cause of the >> problem. On the same host which is doing the bridging, I've got another >> interface (fxp0) which is configured "normally", i.e. it has an IP >> address on the subnet which the bridge divides. >> >> Generally this setup works fine, however every now and then I find that >> the bridge is answering ARP who-has queries for the IP address assigned >> to fxp0. >> > > Can you try this patch. > > cheers, > Andrew > Hi Andrew, Your patch seems to have done the job. I have two identical (for all intents and purposes) machines, one patched the other not. I did a tcpdump for arp packets on both em0 and fxp0 of each host and initiated some arp who-has queries for the IP addresses attached to the fx0 interface on each host. On the patched machine only the fxp0 interface sent an arp-reply. On the unpatched machine not only did fxp0 reply but the em0 interface sent both it's mac as well as the mac of em1, the other side of the bridge. I've done this five times in a row and consistently got the same result. Thanks, Nik