From owner-freebsd-net@FreeBSD.ORG Wed May 19 03:25:15 2004 Return-Path: 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 C8FCA16A4D2; Wed, 19 May 2004 03:25:15 -0700 (PDT) Received: from www.svzserv.kemerovo.su (www.svzserv.kemerovo.su [213.184.65.80]) by mx1.FreeBSD.org (Postfix) with ESMTP id 86CBB43D2F; Wed, 19 May 2004 03:25:13 -0700 (PDT) (envelope-from eugen@kuzbass.ru) Received: from kuzbass.ru (kost [213.184.65.82])i4JAOfBa043775; Wed, 19 May 2004 18:24:41 +0800 (KRAST) (envelope-from eugen@kuzbass.ru) Message-ID: <40AB35DE.DF743CCB@kuzbass.ru> Date: Wed, 19 May 2004 18:24:30 +0800 From: Eugene Grosbein Organization: SVZServ X-Mailer: Mozilla 4.8 [en] (Win98; U) X-Accept-Language: ru,en MIME-Version: 1.0 To: Ruslan Ermilov References: <40A9CF72.85E2EC9D@kuzbass.ru> <20040518105134.GC70919@ip.net.ua> <20040518151506.GC72684@ip.net.ua> Content-Type: text/plain; charset=koi8-r Content-Transfer-Encoding: 7bit cc: Eugene Grosbein cc: net@freebsd.org Subject: Re: multicast arp entry X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 19 May 2004 10:25:15 -0000 Ruslan Ermilov wrote: > > > The long answer could be: you could join to a single multicast > > > group on multiple interfaces, and you will be able to receive > > > multicast on all of them, but if you don't have multicast > > > forwarding enabled, only one interface will be used for sending. > > > > That's bad. How do I enable "multicast forwarding", or, in other words, > > do you know why ripd doesn't do it for be? > > > I use mrouted(8). > > > On the other hand, I've got another machine with very simple configuration: > > one fxp0 interface, one rl0 and one gif0 and started quagga/ripd. > > Two points: tcpdump shows that multicasts go out all three interfaces > > with right source IP and there is no arp entries for 224.0.0.9 and 224.0.0.1. > > > > I couldn't find what is the vital difference between these two machines yet > > (there are so many of them). > > > I don't know. Perhaps, quagga/ripd send raw IP packets in this case. No, it does not. I've finally found that one need not MROUTING and mrouted just to send RIPv2 multicasts out via several interfaces and FreeBSD does it right by default. But if outgoint multicast packet is diverted to ipacctd accounting daemon using 'ipfw divert' then it is sent to an interface pointed by route to 224.0.0.9 instead of right one (no such effect for P2P interfaces, though). I wonder if it's a fault of ipacctd or of divert's way of life. Eugene Grosbein