From owner-freebsd-net Mon Oct 1 13:20:37 2001 Delivered-To: freebsd-net@freebsd.org Received: from InterJet.elischer.org (c421509-a.pinol1.sfba.home.com [24.7.86.9]) by hub.freebsd.org (Postfix) with ESMTP id 5DA2337B429 for ; Mon, 1 Oct 2001 13:20:07 -0700 (PDT) Received: from localhost (localhost.elischer.org [127.0.0.1]) by InterJet.elischer.org (8.9.1a/8.9.1) with ESMTP id OAA87515; Mon, 1 Oct 2001 14:05:57 -0700 (PDT) Date: Mon, 1 Oct 2001 14:05:55 -0700 (PDT) From: Julian Elischer To: "Jasper O'Malley" Cc: freebsd-net@freebsd.org Subject: Re: Netgraph bridging: what is LOCAL_IFACE? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-net@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.org All the interfaces specified will stop working as normal interfaces, as their lower halves will be disconnected from their upper halves.. in other words the lower 'physical' part is run without any connection to the normal networking layer.. The bridging code (netgraph bridging) takes over this function instead. I think that if you send out a packet on one of these interfaces it may still make it out because we don't actually (last time I checked) bother to disconnect that, but all incoming packets will be passed to the bridge module, which will be keeoping track of MAC addresses and doing bridging as required.. Now, if you want to be on that bridged network as well, then you need to nominate which of the NICS should be your representative on that bridged network. The TOP part of that NIC (the bit you assign addresses to) will be joined into the bridging set, just like all the other NICS (logically there is no difference). The bridging code will send it a copy of any packets that have it's MAC address as destination and broadcast packets, just as it would any other segment.. Theoretically wo should remove teh bridged NICs from the ifconfig list but that would be too much work. Basically your NIC is just treated like another bridged segment, but with only one known node on it.. On Mon, 1 Oct 2001, Jasper O'Malley wrote: > On Mon, 1 Oct 2001, Julian Elischer wrote: > > > If you want any of these packets to also be passed to the local machine > > you should select one of the local interfaces (any will do) and add it in > > the LOCAL_INTERFACE entry. This entry specifies to the bridging code that > > the upper (i.e. KERNEL side) of that interface should also be added to the > > list of recipients of the packets being worked on. > > > > If you do not do this, the interfaces are linked to each other by the > > bridging code, but the local machine is not party to the traffic. No copy > > of the packets is sent up to it.. (this is a vaild configuration...) > > Ah. So you can't ifconfig the virtual bridge interface (e.g. bnet0) and > configure IP protocol information on it, then? > > If not, I misunderstood how the bridge interface behaves. I was thinking > that it acted more or less like a BVI interface does on a Cisco router. > Specifying the LOCAL_INTERFACE will work for me, though. Thanks. > > Cheers, > Mick > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message