From owner-freebsd-current@FreeBSD.ORG Wed Jul 28 14:57:41 2004 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 4E84C16A4CF for ; Wed, 28 Jul 2004 14:57:41 +0000 (GMT) Received: from salmon.maths.tcd.ie (salmon.maths.tcd.ie [134.226.81.11]) by mx1.FreeBSD.org (Postfix) with SMTP id 710F943D6A for ; Wed, 28 Jul 2004 14:57:40 +0000 (GMT) (envelope-from dwmalone@maths.tcd.ie) Received: from walton.maths.tcd.ie by salmon.maths.tcd.ie with SMTP id ; 28 Jul 2004 15:57:39 +0100 (BST) Date: Wed, 28 Jul 2004 15:57:38 +0100 From: David Malone To: Brad Knowles Message-ID: <20040728145738.GA47187@walton.maths.tcd.ie> References: <20040726012016.D232E5D0A@ptavv.es.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.3i Sender: dwmalone@maths.tcd.ie cc: current@freebsd.org Subject: Re: Problems with ntp4.2 when names resolve to IPv6 addresses 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, 28 Jul 2004 14:57:41 -0000 On Tue, Jul 27, 2004 at 11:46:31PM +0200, Brad Knowles wrote: > At 6:20 PM -0700 2004-07-25, Kevin Oberman wrote: > > I did not notice any problem while I was on an IPv6 connected network at > > work or while on travel at a networking conference as they have IPv6 > > connectivity, but when I tried from home, where my broadband provider > > does not provide any IPv6 routing, ntp simply spits out messages that it > > failed to connect to each server. > This may be a bug with the base code from ntp.org. We'd want to > know more about this particular problem. Can you file a bug at > bugzilla.ntp.org? Ntpd has some issues in this area. It will always try the first address returned by getaddrinfo and doesn't fall back to other addresses if things don't work out. This means if you don't have IPv6 connectivity, but your server does have an AAAA record, then you probably won't be able to talk NTP to the server. The fix is to change ntp.conf to say "server -4 server.name" rather than just "server server.name". (The same problem exists with servers with multiple IPv4 addresses, some of which are unreachable, it's just less obvious...) David.