From owner-freebsd-current@FreeBSD.ORG Mon Oct 5 18:54:13 2009 Return-Path: Delivered-To: freebsd-current@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 03BAB1065672; Mon, 5 Oct 2009 18:54:13 +0000 (UTC) (envelope-from oberman@es.net) Received: from mailgw.es.net (mail1.es.net [IPv6:2001:400:201:1::2]) by mx1.freebsd.org (Postfix) with ESMTP id DB4EE8FC16; Mon, 5 Oct 2009 18:54:12 +0000 (UTC) Received: from ptavv.es.net (ptavv.es.net [IPv6:2001:400:910::29]) by mailgw.es.net (8.14.3/8.14.3) with ESMTP id n95Is8Lb016473 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 5 Oct 2009 11:54:08 -0700 Received: from ptavv.es.net (ptavv.es.net [127.0.0.1]) by ptavv.es.net (Tachyon Server) with ESMTP id 728471CC0E; Mon, 5 Oct 2009 11:54:08 -0700 (PDT) To: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= In-reply-to: Your message of "Mon, 05 Oct 2009 20:08:40 +0200." <86my45vhlj.fsf@ds4.des.no> Date: Mon, 05 Oct 2009 11:54:08 -0700 From: "Kevin Oberman" Message-Id: <20091005185408.728471CC0E@ptavv.es.net> X-Proofpoint-Virus-Version: vendor=fsecure engine=1.12.8161:2.4.5, 1.2.40, 4.0.166 definitions=2009-10-05_12:2009-09-29, 2009-10-05, 2009-10-05 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 ipscore=0 phishscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx engine=5.0.0-0908210000 definitions=main-0910050111 Cc: jhay@meraka.org.za, freebsd-current@FreeBSD.org, Hiroki Sato , freebsd-rc@FreeBSD.org Subject: Re: nd6 change and rc.d/network_ipv6 -> rc.d/netif integration X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 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: Mon, 05 Oct 2009 18:54:13 -0000 > From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= > Date: Mon, 05 Oct 2009 20:08:40 +0200 > Sender: owner-freebsd-current@freebsd.org > > Hiroki Sato writes: > > John Hay writes: > > > Is there a good reason why we still ship with ipv6 off by default? > > What do you mean by "off by default"? I think IPv6 is not disabled by > > default with the patch. > > % ident /usr/src/etc/defaults/rc.conf > /usr/src/etc/defaults/rc.conf: > $FreeBSD: head/etc/defaults/rc.conf 197619 2009-09-29 16:49:10Z dougb $ > % grep ipv6_network_interfaces /usr/src/etc/defaults/rc.conf > ipv6_network_interfaces="none" # List of IPv6 network interfaces > #ipv6_network_interfaces="ed0 ep0" # Examples for router > % grep ipv6_prefer /usr/src/etc/defaults/rc.conf > ipv6_prefer="NO" # Use IPv6 when both IPv4 and IPv6 can be used > > Does mean that IPv6 is disabled by default? Who knows? There is no > coherent explanation *anywhere* of what these variables mean, and > rc.conf(5) does not mention them at all. In fact, the first hit for > "ipv6" in rc.conf(5) is this: > > ipv6_enable > (bool) Enable support for IPv6 networking. Note that this > requires that the kernel has been compiled with options > INET6. Am I missing something here? From the same /etc/defaults/rc.conf: ### IPv6 options: ### ipv6_enable="NO" # Set to YES to set up for IPv6. That looks about a "disabled out of the box" as it gets. As far as I can see (which may not be far), ipv6_network_interfaces is only relevant to IPv6 routing. I believe that ipv6_prefer controls the default behavior when DNS returns both IPv4 and IPv6 addresses for a host. If it is set to "NO", IPv4 will be tried first (preferred). If set to "YES", the IPv6 address will be preferred. I strongly recommend keeping ipv6_prefer set to "NO". -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751