From owner-freebsd-net@FreeBSD.ORG Wed Aug 23 22:18:54 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 D0BE316A591; Wed, 23 Aug 2006 22:18:54 +0000 (UTC) (envelope-from brooks@lor.one-eyed-alien.net) Received: from sccmmhc91.asp.att.net (sccmmhc91.asp.att.net [204.127.203.211]) by mx1.FreeBSD.org (Postfix) with ESMTP id B1B4043D6B; Wed, 23 Aug 2006 22:18:42 +0000 (GMT) (envelope-from brooks@lor.one-eyed-alien.net) Received: from lor.one-eyed-alien.net ([12.207.12.9]) by sccmmhc91.asp.att.net (sccmmhc91) with ESMTP id <20060823221840m910087qh3e>; Wed, 23 Aug 2006 22:18:41 +0000 Received: from lor.one-eyed-alien.net (localhost [127.0.0.1]) by lor.one-eyed-alien.net (8.13.6/8.13.6) with ESMTP id k7NMIcwT029026; Wed, 23 Aug 2006 17:18:38 -0500 (CDT) (envelope-from brooks@lor.one-eyed-alien.net) Received: (from brooks@localhost) by lor.one-eyed-alien.net (8.13.6/8.13.6/Submit) id k7NMIaiT029025; Wed, 23 Aug 2006 17:18:36 -0500 (CDT) (envelope-from brooks) Date: Wed, 23 Aug 2006 17:18:36 -0500 From: Brooks Davis To: Pat Lashley Message-ID: <20060823221835.GA28978@lor.one-eyed-alien.net> References: <44EA1926.2000501@shapeshifter.se> <9C04919EE684029A410DE208@garrett.local> <44EAC40E.9000904@shapeshifter.se> <3E654CC0217F90E20FCD806E@garrett.local> <44EC90B7.6090908@shapeshifter.se> <44ECB0F2.9040300@FreeBSD.org> <20060823212110.GD27961@lor.one-eyed-alien.net> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="d6Gm4EdcadzBjdND" Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.11 Cc: freebsd-net@freebsd.org, Doug Barton , Fredrik Lindberg Subject: Re: Zeroconfig and Multicast DNS 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: Wed, 23 Aug 2006 22:18:55 -0000 --d6Gm4EdcadzBjdND Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Aug 23, 2006 at 03:07:32PM -0400, Pat Lashley wrote: > >> I would agree that LLA is part of the minimal set; and as I mentioned > >> before, it is the only part for which there is currently no FreeBSD > >> solution. It should be possible to enable LLA on a per-NIC basis in > >> rc.conf; and it should be possible to have both LLA and non-LLA addres= ses > >> on the same port so that a FreeBSD host can easily operate in a mixed > >> environment. (This also makes it easier for portable machines to handle > >> being moved between a zeroconf-based environment and a more traditional > >> DHCP environment.) > > > >I don't see how we can do the fallback stuff with our current > >infrastructure. You could do it with profile.sh, but our current > >infrastructure isn't really suited to it. In some ways what we really > >need is an all knowing IPv4 address configuration program that can probe > >the link and decide if it should a) use a static IP, b) use DHCP, or c) > >use an LLA. It's possible we could do this in a shell script, but I'm > >not sure we'd want to. >=20 > I don't think those should necessarily be mutually exclusive. I'd much= =20 > rather see something that uses aliases so that I can easily have both an= =20 > LLA and a non-LLA address on the same interface. The only potentially=20 > tricky part is that the RFC requires (quite rightly) that in such a=20 > situation, the non-LLA address be preferred. If it were strictly a 'pick= =20 > one' situation; then we could just extend our current setup so that the= =20 > DHCP client could be told to fall back to LLA if it can't obtain a lease. >=20 > I suspect that it will be less common to want to use both an LL/DHCP=20 > address and a static address; but I certainly wouldn't rule it out. (In= =20 > fact, now that I think about it, I'm likely to run into that situation=20 > during the transition of my LAN from static RFC-1918 addresses to LLA.) DHCP+static is rather weird, but common enough that we do support it. I suspect LLA with other address types is also of use at least some of the time so we should ideally support it. Actually if we don't mind always configuring a LLA I think we might support be OK right now as long as the LLA daemon leaves non-LLA addresses alone. The one thing I'd be worried about is how the socket code handles connect() requests. My hope would be that it would pick the address that goes with the router to be used and thus the LLA would never be the source of a packet going to a non-LLA address in normal circumstances. -- Brooks --d6Gm4EdcadzBjdND Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (FreeBSD) iD8DBQFE7NQ7XY6L6fI4GtQRAvqkAJ92S8/0ICtCbVazU33uU8bji3XsoQCgkEAk vGlxsju/ZAdu9OZ9GIwcY44= =/9rs -----END PGP SIGNATURE----- --d6Gm4EdcadzBjdND--