Dns on Evan Hoffman

Benchmarking DNS servers with Java

Mon, 26 Sep 2011 12:33:28 +0000

I’m currently in the process of moving our DNS over to another provider and I was curious as to whether the old or new provider offers faster lookups. dig shows query times, but I didn’t want to just run that over and over. I decided to write something to do this, in Java since I like Java. I found this post, which has the meat of the work done already. I also read some of Sun’s JNDI/DNS lookup info, which was pretty dense. All I want to do is specify the name server’s IP and do the lookup. I don’t even really care about the result, just how long the query takes.

Back on FiOS again (finally)

Fri, 20 May 2011 13:35:01 +0000

Well, that was quite an ordeal.

Going back to FiOS

Sun, 24 Apr 2011 01:40:05 +0000

I’m not sure why these guys operate this way - they’re more than happy to lose me as a customer and then throw huge discounts at me to get me back. If they’d just give me a good price I’d love not to have to go through this rigmarole. But after being with Cablevision for 2 months I checked Verizon’s pricing and it beat my current deal with Cablevision.

FiOS digital voice with number ported for free; 25/25 Mbps internet; HMDVR free “forever” plus a second HD STB, Showtime, Movie Channel and Flix. Since I already had the battery thing installed last time I had FiOS they gave me a fair discount. Basically the whole package for $87/month + tax, price locked for 2 years, no contract. Not as great of a deal as I’d had with FiOS originally, but it’s pretty good, and FiOS’s service is definitely better than Cablevision’s. I’ve heard Cablevision was rolling out their “DVR plus” service with all programs recorded “in the cloud” rather than on the actual box, but it’s been two months and I haven’t heard of it coming to Long Island. So basically 2 years later Cablevision’s service is exactly the same while Verizon has iPhone apps to control the DVR and use the phone as a remote, plus DVR that’s much faster and just generally better service.

More fun parsing BIND query logs

Mon, 13 Dec 2010 18:21:59 +0000

“But wouldn’t it be cool if it also…” That phrase usually triggers a lot of wasted cycles in my brain, though it sometimes comes up with something neat. I added a super lame graph to the DNS QPS parser. Makes it really easy to see peaks & troughs in usage:

2010-12-12 00:00 to 00:59 => 3237, rate 0.899 queries/sec	***********
2010-12-12 01:00 to 01:59 => 2709, rate 0.752 queries/sec	**********
2010-12-12 02:00 to 02:59 => 2473, rate 0.687 queries/sec	*********
2010-12-12 03:00 to 03:59 => 2171, rate 0.603 queries/sec	********
2010-12-12 04:00 to 04:59 => 2048, rate 0.569 queries/sec	*******
2010-12-12 05:00 to 05:59 => 1918, rate 0.533 queries/sec	*******
2010-12-12 06:00 to 06:59 => 2120, rate 0.589 queries/sec	********
2010-12-12 07:00 to 07:59 => 2477, rate 0.688 queries/sec	*********
2010-12-12 08:00 to 08:59 => 2994, rate 0.832 queries/sec	**********
2010-12-12 09:00 to 09:59 => 3704, rate 1.029 queries/sec	*************
2010-12-12 10:00 to 10:59 => 4297, rate 1.194 queries/sec	***************
2010-12-12 11:00 to 11:59 => 4744, rate 1.318 queries/sec	****************
2010-12-12 12:00 to 12:59 => 5106, rate 1.418 queries/sec	******************
2010-12-12 13:00 to 13:59 => 5311, rate 1.475 queries/sec	******************
2010-12-12 14:00 to 14:59 => 5083, rate 1.412 queries/sec	*****************
2010-12-12 15:00 to 15:59 => 4855, rate 1.349 queries/sec	*****************
2010-12-12 16:00 to 16:59 => 5179, rate 1.439 queries/sec	******************
2010-12-12 17:00 to 17:59 => 4959, rate 1.377 queries/sec	*****************
2010-12-12 18:00 to 18:59 => 4693, rate 1.304 queries/sec	****************
2010-12-12 19:00 to 19:59 => 4792, rate 1.331 queries/sec	****************
2010-12-12 20:00 to 20:59 => 4799, rate 1.333 queries/sec	****************
2010-12-12 21:00 to 21:59 => 5068, rate 1.408 queries/sec	*****************
2010-12-12 22:00 to 22:59 => 4672, rate 1.298 queries/sec	****************
2010-12-12 23:00 to 23:59 => 4514, rate 1.254 queries/sec	****************
2010-12-13 00:00 to 00:59 => 3917, rate 1.088 queries/sec	**************
2010-12-13 01:00 to 01:59 => 3458, rate 0.961 queries/sec	************
2010-12-13 02:00 to 02:59 => 2874, rate 0.798 queries/sec	**********
2010-12-13 03:00 to 03:59 => 2715, rate 0.754 queries/sec	**********
2010-12-13 04:00 to 04:59 => 2690, rate 0.747 queries/sec	*********
2010-12-13 05:00 to 05:59 => 2719, rate 0.755 queries/sec	**********
2010-12-13 06:00 to 06:59 => 2831, rate 0.786 queries/sec	**********
2010-12-13 07:00 to 07:59 => 3416, rate 0.949 queries/sec	************
2010-12-13 08:00 to 08:59 => 4962, rate 1.378 queries/sec	*****************
2010-12-13 09:00 to 09:59 => 6943, rate 1.929 queries/sec	************************
2010-12-13 10:00 to 10:59 => 8296, rate 2.304 queries/sec	****************************
2010-12-13 11:00 to 11:59 => 8938, rate 2.483 queries/sec	******************************
2010-12-13 12:00 to 12:59 => 8926, rate 2.479 queries/sec	******************************
2010-12-13 13:00 to 13:59 => 8950, rate 2.486 queries/sec	******************************
2010-12-13 14:00 to 14:59 => 2173, rate 0.604 queries/sec	********

You can see pretty quickly that 4-5 AM (Eastern) is the period of lowest activity, as you’d probably expect for a US-based US-centric site. Modified perl script below.

Perl script to calculate DNS queries per second in BIND (named)

Tue, 07 Dec 2010 18:53:43 +0000

I’m pricing out DNS providers and was asked what our current queries-per-second currently are. Sadly I had no idea. After lots of Googling I decided there was really no good way to get this information so I decided to parse the logfile myself. First, I turned on logging with timestamp in named.conf:

logging
{
...
 # Query logging 2010-12-07
 channel query-log {
 file "data/queries.log" versions 3 size 10m;
 print-time yes;
 };
 category queries { query-log; };
};
options
{
...
 # Query logging 2010-12-07
 querylog yes;

};

Outlook 2007 & Exchange 2010 Autodiscover SSL certificate error annoyance

Tue, 27 Jul 2010 11:51:54 +0000

One of the more annoying side effects of migrating my mailbox to Exchange 2010 has been the nagging of Outlook 2007’s Autodiscovery feature. Now, every time I start Outlook I get hit with a certificate error for autodiscover.domain.com. Now, autodiscover.domain.com is a CNAME to mail.domain.com, which is the OWA URL for the CAS. The SSL certificate is valid - but it’s valid for mail.domain.com. I could buy a SSL certificate from GoDaddy for $12.99 (an insanely great price, btw) for “autodiscover” but that would also require using another IP address on the CAS (since you can can only bind one SSL certificate to an IP:port pair), and that seems like a waste of an IP address.