From owner-freebsd-stable@FreeBSD.ORG Thu May 4 22:03:30 2006 Return-Path: X-Original-To: stable@freebsd.org Delivered-To: freebsd-stable@FreeBSD.ORG Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 96EAF16A402 for ; Thu, 4 May 2006 22:03:30 +0000 (UTC) (envelope-from freebsd-stable@lists.b0rken.net) Received: from water.b0rken.net (ip-1.b0rken.net [194.7.227.1]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2AD5B43D45 for ; Thu, 4 May 2006 22:03:29 +0000 (GMT) (envelope-from freebsd-stable@lists.b0rken.net) Received: from fire.b0rken.net ([172.16.1.10]) by water.b0rken.net with esmtp (Exim 4.34) id 1FadW6-0001kP-DU for stable@freebsd.org; Mon, 01 May 2006 20:53:06 +0200 Received: by fire.b0rken.net (Postfix, from userid 502) id 50B162DB8; Mon, 1 May 2006 20:46:40 +0200 (CEST) Date: Mon, 1 May 2006 20:46:40 +0200 From: Jan Gyselinck To: stable@freebsd.org Message-ID: <20060501204640.B8351@fire.b0rken.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.3.23i X-Mailer: Mutt Cc: Subject: resolver behaviour regarding searchlist and A/AAAA query replies X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: Jan Gyselinck List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 04 May 2006 22:03:30 -0000 Hi, I was debugging some connection lag and I encountered some query behavior which seems unnecessairy in my eyes. The system in question is running one of the FreeBSD 6.1 prereleases, I've not verified this on any other version yet. The queries I see are these: 22:15:29.657232 IP 172.16.21.2.57672 > 172.16.1.22.53: 54355+ A? images.slashdot.org. (37) 22:15:29.658189 IP 172.16.21.2.64080 > 172.16.1.22.53: 46066+ AAAA? images.slashdot.org. (37) 22:15:29.659407 IP 172.16.1.22.53 > 172.16.21.2.57672: 54355 1/13/1 A 66.35.250.55 (280) 22:15:29.659674 IP 172.16.1.22.53 > 172.16.21.2.64080: 46066 0/1/0 (96) 22:15:29.660514 IP 172.16.21.2.55636 > 172.16.1.22.53: 46067+ AAAA? images.slashdot.org.b0rken.net. (48) 22:15:29.661438 IP 172.16.1.22.53 > 172.16.21.2.55636: 46067 NXDomain* 0/1/0 (99) 22:15:29.661847 IP 172.16.21.2.58524 > 172.16.1.22.53: 46068+ AAAA? images.slashdot.org.bureau.b0rken.net. (55) 22:15:29.662720 IP 172.16.1.22.53 > 172.16.21.2.58524: 46068 NXDomain* 0/1/0 (106) So it sends out A and AAAA queries, so far so good. It gets an answer for the A record query, however the AAAA query retuns an empty answer. What I find strange though, is the fact it's now applying the searchlist to get an answer on the AAAA query. Other than the fact this could potentially give unpredictable results in specific situations, I find this rather illogical. Since one of the queries (A or AAAA) succeeded we _know_ the host in question exists (and the searchlist is there to make non-fqdn queries work for 'local' hosts, by applying the searchlist if the host does not seem to exist). So, in short, isn't this a bug? Regards Jan Gyselinck