From owner-freebsd-net@FreeBSD.ORG Thu Oct 23 01:55:57 2003 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 3E52D16A4B3 for ; Thu, 23 Oct 2003 01:55:57 -0700 (PDT) Received: from smtp.omnis.com (smtp.omnis.com [216.239.128.26]) by mx1.FreeBSD.org (Postfix) with ESMTP id A786343F85 for ; Thu, 23 Oct 2003 01:55:56 -0700 (PDT) (envelope-from wes@softweyr.com) Received: from softweyr.homeunix.net (66-91-236-204.san.rr.com [66.91.236.204]) by smtp-relay.omnis.com (Postfix) with ESMTP id 818BC72E22; Thu, 23 Oct 2003 01:51:56 -0700 (PDT) From: Wes Peters Organization: Softweyr To: Barney Wolff , net@freebsd.org Date: Thu, 23 Oct 2003 01:55:55 -0700 User-Agent: KMail/1.5.4 References: <20031020174751.60464.qmail@web20805.mail.yahoo.com> <20031021214932.GA659@saboteur.dek.spc.org> <20031021222307.GA80895@pit.databus.com> In-Reply-To: <20031021222307.GA80895@pit.databus.com> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200310230155.55363.wes@softweyr.com> Subject: Re: Help Broadcasting a UDP packet on the LAN:URGENT 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: Thu, 23 Oct 2003 08:55:57 -0000 On Tuesday 21 October 2003 03:23 pm, Barney Wolff wrote: > Bruce M Simpson wrote pointing > out AODV (RFC 3561) as an example of a routing protocol needing to > send to 255.255.255.255 on multiple interfaces at once. I withdraw > my scorn of kernel mods to facilitate this. To me it's not a matter of "boot code" vs. general usefulness so much as it's just obviously the right way to do it. We use all-ones packets well after boot to have our appliances identify each other on the network and share configuration information, and it's not always evident which network interface(s) they should be using to do this. The current code binds to each of the interfaces and blats out a packet, but it just seems obvious that the all-ones address implies all attached interfaces because you have a per-network broadcast address if you want to do per-interface broadcasts. I've been working with Bruce on this and there are parts that still worry me. If you want to poke holes in the thinking we've been doing, I'm always happy to have another set of eyeballs on the design and I'm sure Bruce will too. Interactions with VLANs, for instance. If you send an all-ones broadcast on an interface that has one or more VLANs configured, do you repeat them "on" each VLAN as well? Ugh. What about point-to-point links? Are those always considered gateways to a foreign network, or just another form of locally attached network? I'm pretty certain the code won't be all that difficult if we just fully understand the problem before we jump in, but I'm also pretty certain we don't fully understand the problem, let alone the solution. ;^) -- Where am I, and what am I doing in this handbasket? Wes Peters wes@softweyr.com