From owner-freebsd-current@FreeBSD.ORG Tue Oct 28 16:30:14 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id AA63716A4CE for ; Tue, 28 Oct 2003 16:30:14 -0800 (PST) Received: from mail.inka.de (quechua.inka.de [193.197.184.2]) by mx1.FreeBSD.org (Postfix) with ESMTP id 99FB443FDD for ; Tue, 28 Oct 2003 16:30:13 -0800 (PST) (envelope-from mailnull@mips.inka.de) Received: from kemoauc.mips.inka.de (uucp@) by mail.inka.de with gbsmtp id 1AEeE0-0002QV-01; Wed, 29 Oct 2003 01:30:12 +0100 Received: from kemoauc.mips.inka.de (localhost [127.0.0.1]) h9SNq142089138 for ; Wed, 29 Oct 2003 00:52:01 +0100 (CET) (envelope-from mailnull@kemoauc.mips.inka.de) Received: (from mailnull@localhost) by kemoauc.mips.inka.de (8.12.10/8.12.10/Submit) id h9SNq0cv089137 for freebsd-current@freebsd.org; Wed, 29 Oct 2003 00:52:00 +0100 (CET) (envelope-from mailnull) From: naddy@mips.inka.de (Christian Weisgerber) Date: Tue, 28 Oct 2003 23:51:59 +0000 (UTC) Message-ID: References: <20031028063802.GC10818@canolog.ninthwonder.com> Originator: naddy@mips.inka.de (Christian Weisgerber) To: freebsd-current@freebsd.org Subject: Re: Forward: HEADS UP! Default value of ip6_v6only changed X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 29 Oct 2003 00:30:14 -0000 Hajimu UMEMOTO wrote: > Our default of net.inet6.ip6.v6only was off in 4.X, and was changed to > on on 5.X to follow NetBSD's practice. This behavior on 5.X breaks > RFC2553/3493, and the change was intentional from security > consideration. But, NetBSD changed it off by default. OpenBSD's behavior is equivalent to v6only on, and OpenBSD doesn't even provide a knob. Note that the default choice has a major impact on 3rd party software (ports). If we ship with a default of v6only off, then people will not fix software to open two sockets. This in turn means that turning v6only on will break this software. I predict that a good many people will then consider the v6only option to be useless. I understand that itojun would like to see this aspect of RFC2553 amended. I don't know what the prospects of this happening are on the IETF level. -- Christian "naddy" Weisgerber naddy@mips.inka.de