From owner-freebsd-questions@FreeBSD.ORG Fri Nov 2 04:07:07 2007 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 35AE916A41B for ; Fri, 2 Nov 2007 04:07:07 +0000 (UTC) (envelope-from iaccounts@ibctech.ca) Received: from pearl.ibctech.ca (pearl.ibctech.ca [208.70.104.210]) by mx1.freebsd.org (Postfix) with ESMTP id D9CD013C494 for ; Fri, 2 Nov 2007 04:07:06 +0000 (UTC) (envelope-from iaccounts@ibctech.ca) Received: (qmail 93890 invoked by uid 1002); 2 Nov 2007 04:06:40 -0000 Received: from iaccounts@ibctech.ca by pearl.ibctech.ca by uid 89 with qmail-scanner-1.22 (spamassassin: 2.64. Clear:RC:1(208.70.104.100):. Processed in 6.585273 secs); 02 Nov 2007 04:06:40 -0000 Received: from unknown (HELO ?192.168.30.110?) (steve@ibctech.ca@208.70.104.100) by pearl.ibctech.ca with (DHE-RSA-AES256-SHA encrypted) SMTP; 2 Nov 2007 04:06:33 -0000 Message-ID: <472AA1D4.8070105@ibctech.ca> Date: Fri, 02 Nov 2007 00:04:36 -0400 From: Steve Bertrand User-Agent: Thunderbird 2.0.0.6 (Windows/20070728) MIME-Version: 1.0 To: Jonathan Horne References: <200711012041.13641.freebsd@dfwlp.com> In-Reply-To: <200711012041.13641.freebsd@dfwlp.com> X-Enigmail-Version: 0.95.4 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: freebsd-questions@freebsd.org Subject: Re: curious DNS behavior on a 7.0... X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 02 Nov 2007 04:07:07 -0000 Jonathan Horne wrote: > reading the /etc/defaults/rc.conf, ipv6 appears disabled by default: > > ### IPv6 options: ### > ipv6_enable="NO" # Set to YES to set up for IPv6. > > however, right now "new" every website i browse is penalized with a 10-20 > second delay before the page finally starts loading. tcpdump is full of > these: > > 20:38:57.915695 IP athena.dfwlp.com.59056 > castor.dfwlp.com.domain: 3505+ > AAAA? www.srh.noaa.gov. (34) > > arent AAAA's ipv6 lookups? as i mentioned in another thread, i cant get the > kernel to compile right now (thus eliminating the INET6 line), so im trying > to figure another way out to stop this behavior). It's not required you remove IPv6 from the kernel in order to receive proper DNS A record responses, and even if IPv6 name services take precedence, it shouldn't cause such a delay (unless all of your boxen/DNS servers point to the same forwarders that cause this issue). I have several machines under 4.10 to 6.2, and at least two running 7.0 that are v6 enabled that don't have this issue. I do run IPv6 in my network with a legitimate block, however, I do not have any IPv6 name servers that contain any outside DNSv6 records. That said, more particulars are needed to find out what is happening. The most important thing to know in order to break this down is what name server(s) are you using on this particular server to resolve names. If you can post the output from the following whilst logged into one of the problematic machines, it will likely help: # cat /etc/resolv.conf If your box is a DHCP client, I won't know what to look for in that output. If by chance your box attains it's IP information via DHCP, then the next following output (particularly the last few lines) will help: # dig www.srh.noaa.gov Your AAAA queries may or may not be detrimental to the time in which you receive your DNS responses. I would personally lean toward the latter, given the lack of information. Don't go about recompiling the kernel without v6 support yet. It seems DNS is timing out for you somewhere, so post the above requested info and it can go from there. Steve