From owner-freebsd-net@FreeBSD.ORG Wed Feb 13 01:32:12 2008 Return-Path: Delivered-To: freebsd-net@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 34C2216A419; Wed, 13 Feb 2008 01:32:12 +0000 (UTC) (envelope-from delphij@delphij.net) Received: from tarsier.delphij.net (delphij-pt.tunnel.tserv2.fmt.ipv6.he.net [IPv6:2001:470:1f03:2c9::2]) by mx1.freebsd.org (Postfix) with ESMTP id CFA6A13C43E; Wed, 13 Feb 2008 01:32:11 +0000 (UTC) (envelope-from delphij@delphij.net) Received: from tarsier.geekcn.org (unknown [202.108.54.204]) (using TLSv1 with cipher ADH-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by tarsier.delphij.net (Postfix) with ESMTP id 7AD2A28480; Wed, 13 Feb 2008 09:32:10 +0800 (CST) Received: from localhost (unknown [202.108.54.204]) by tarsier.geekcn.org (Postfix) with ESMTP id 1A7FAEB390B; Wed, 13 Feb 2008 09:32:10 +0800 (CST) X-Virus-Scanned: amavisd-new at geekcn.org Received: from tarsier.geekcn.org ([202.108.54.204]) by localhost (mail.geekcn.org [202.108.54.204]) (amavisd-new, port 10024) with ESMTP id krd9WdWDde8H; Wed, 13 Feb 2008 09:32:01 +0800 (CST) Received: from charlie.delphij.net (71.5.7.139.ptr.us.xo.net [71.5.7.139]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by tarsier.geekcn.org (Postfix) with ESMTP id 3560FEB359B; Wed, 13 Feb 2008 09:31:59 +0800 (CST) DomainKey-Signature: a=rsa-sha1; s=default; d=delphij.net; c=nofws; q=dns; h=message-id:date:from:reply-to:organization:user-agent: mime-version:to:cc:subject:x-enigmail-version:openpgp:content-type:content-transfer-encoding; b=ZcsP8icm8jY71jzO8/CcqenrU4zDAwHk+kjupntiAUZr28Vy8l4lL0K6dNWlQ2FOU aN+lXxDwKpRLCO23TcBsA== Message-ID: <47B2488D.70707@delphij.net> Date: Tue, 12 Feb 2008 17:31:57 -0800 From: Xin LI Organization: The FreeBSD Project User-Agent: Thunderbird 2.0.0.9 (X11/20080122) MIME-Version: 1.0 To: freebsd-net@freebsd.org X-Enigmail-Version: 0.95.5 OpenPGP: id=18EDEBA0; url=http://www.delphij.net/delphij.asc Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: ume@FreeBSD.org Subject: Strange resolver behavior X-BeenThere: freebsd-net@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: d@delphij.net List-Id: Networking and TCP/IP with FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 13 Feb 2008 01:32:12 -0000 -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hi, It looks like that certain (mis)configuration by the baidu.com DNS administrators has caused this, but I have no clue why our resolver would return NXDOMAIN after it gets a positive response? (Yes, I know that _ is not appropriate for domain names :) [delphij@charlie] ~> host -a dict.baidu.com Trying "dict.baidu.com" ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 59711 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 0 ;; QUESTION SECTION: ;dict.baidu.com. IN ANY ;; ANSWER SECTION: dict.baidu.com. 7153 IN CNAME ps_other.a.shifen.com. ;; AUTHORITY SECTION: baidu.com. 159107 IN NS ns4.baidu.com. baidu.com. 159107 IN NS ns2.baidu.com. baidu.com. 159107 IN NS ns3.baidu.com. baidu.com. 159107 IN NS dns.baidu.com. Received 136 bytes from 127.0.0.1#53 in 31 ms [delphij@charlie] ~> host -a ps_other.a.shifen.com Trying "ps_other.a.shifen.com" ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64825 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 4, ADDITIONAL: 0 ;; QUESTION SECTION: ;ps_other.a.shifen.com. IN ANY ;; ANSWER SECTION: ps_other.a.shifen.com. 1113 IN A 202.108.22.46 ;; AUTHORITY SECTION: a.shifen.com. 72679 IN NS ns3.a.shifen.com. a.shifen.com. 72679 IN NS ns2.a.shifen.com. a.shifen.com. 72679 IN NS ns4.a.shifen.com. a.shifen.com. 72679 IN NS ns1.a.shifen.com. Received 127 bytes from 127.0.0.1#53 in 0 ms [delphij@charlie] ~> host ps_other.a.shifen.com ps_other.a.shifen.com has address 202.108.22.46 Host ps_other.a.shifen.com not found: 3(NXDOMAIN) Cheers, - -- Xin LI http://www.delphij.net/ FreeBSD - The Power to Serve! -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.4 (FreeBSD) iD8DBQFHskiNi+vbBBjt66ARAhO0AKCI64gr+oNw7j8/TcL51b7vw1PReQCeMRE1 RaI38+YYtloZuSc0L0BDF2M= =ONkQ -----END PGP SIGNATURE-----