From owner-freebsd-net@freebsd.org Tue Oct 9 00:34:15 2018 Return-Path: Delivered-To: freebsd-net@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id B702210AC1AB for ; Tue, 9 Oct 2018 00:34:15 +0000 (UTC) (envelope-from vas@mpeks.tomsk.su) Received: from admin.sibptus.ru (admin.sibptus.ru [IPv6:2001:19f0:5001:21dc:5400:1ff:feaf:6afb]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 5BFAB88231; Tue, 9 Oct 2018 00:34:15 +0000 (UTC) (envelope-from vas@mpeks.tomsk.su) Received: from vas by admin.sibptus.ru with local (Exim 4.91 (FreeBSD)) (envelope-from ) id 1g9fyY-000MTF-Hc; Tue, 09 Oct 2018 07:34:14 +0700 Date: Tue, 9 Oct 2018 07:34:14 +0700 From: Victor Sudakov To: Alan Somers Cc: Kevin Oberman , FreeBSD Net , citrin+bsd@citrin.ru Subject: Re: why rtsold ? Message-ID: <20181009003414.GA86342@admin.sibptus.ru> References: <20180930022007.GA2041@admin.sibptus.ru> <20181008170044.GA80041@admin.sibptus.ru> <20181009001644.GA86174@admin.sibptus.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-PGP-Key: http://www.dreamwidth.org/pubkey?user=victor_sudakov X-PGP-Fingerprint: 10E3 1171 1273 E007 C2E9 3532 0DA4 F259 9B5E C634 User-Agent: Mutt/1.10.1 (2018-07-13) Sender: Victor Sudakov X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.27 Precedence: list List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 09 Oct 2018 00:34:15 -0000 Alan Somers wrote: > > > > > > When running FreeBSD as an IPv6 host im SLAAC mode, is > > > > > > "rtsold_enable=YES" really necessary? I did not enable rtsold and > > IPv6 > > > > > > still works fine only with > > > > > > > > > > rtsold is needed to write DNS server address from RDNSS RA option to > > > > > /etc/resolv.conf > > > > > > > > > > man rtsold > > > > > /-R > > > > > > > > On my test IPv6-only host, /etc/resolv.conf was successfully created > > > > without any explicit "rtsold_enable=YES". > > > > > > > > -- > > > > Victor Sudakov, VAS4-RIPE, VAS47-RIPN > > > > 2:5005/49@fidonet http://vas.tomsk.ru/ > > > > > > > Remember that DHCPv6 can provide DNS server and other information even > > when > > > SLAAC is used for address configuration. If it is, it is possible to run > > > SLAAC without rtsold, but it may not prove stable as it is not possible > > to > > > > The case is that my IPv6 lab (actually a number of FreeBSD hosts in > > bhyve) does not have a DHCPv6 server. Still, the /etc/resolv.conf on > > IPv6-only hosts is successfully populated from the router. The latter > > is running only rtadvd with the following config: > > > > > > bridge0:rdnss="2001:470:20::2,2001:4860:4860::8888,2001:4860:4860::8844":dnssl=" > > sibptus.ru": > > > > Magick? > > > > Not at all. rtsol will populate /etc/resolv.conf just fine. I see. As I come to think about it, I even don't know how to enable a DHCPv6 client. In my test IPv6-only host, I keep only the following in rc.conf.local: ifconfig_vtnet0="" ifconfig_vtnet0_ipv6="inet6 accept_rtadv" ipv6_privacy="YES" > But it only does it once. rtsold is needed in case router info > changes, or your address times out. -Alan Now I understand, thank you. -- Victor Sudakov, VAS4-RIPE, VAS47-RIPN 2:5005/49@fidonet http://vas.tomsk.ru/