Fix Slow External DNS Resolution in Microsoft/Active Directory DNS Server
Aw yaille! I just wrote up a whole explanatory blog post then lost it so this one will likely be brief... or not.
Recently, we found that one of our DNS servers was resolving external hostnames unacceptably slow -- about 5 seconds, give or take. The resolution was so slow, in fact, that all of the clients hopped on to the secondary DNS server thinking that the primary had gone down. After logging on to the server to troubleshoot, I could see that:
1. Pinging external hostnames worked well after the hostname resolved. So did traceroute.
2. Caching wasn't working at all
2. Other AD DNS servers on the network were resolving external hostnames quickly
3. The root servers were all there but I deleted and reloaded them anyway
- Note: you can actually load root servers from a root server which is cool
4. Internal hostname resolution was extremely fast
5. A reboot didn't help (you may laugh but this has solved severe AD problems for me)
Because the other AD Servers were picking up the slack, I decided to come back to it later. I went out and had dinner with a friend then returned after a few hours. Upon logging back on to the Internets, an old network admin friend messaged me. I told him what I was seeing and he said he had the exact same issue a few months back. After a few minutes of trying to recall the solution, he asked "Have you checked your forwarders?" I'd glanced at them but went back to check again. And there it was.. an entry to a machine we'd recently taken down (long story..). I knew the moment I saw the IP that it was the problem. I removed the entry and noticed the forwarded query timeout was equal to *drumroll* 5 seconds.
Finding that solution was impossible on the Internet because of the super general terms: Slow DNS Resolution External Active Directory. Nothing really worked for me so hopefully this post will help others in the future.
Update: A colleague of mine mentioned spyware interfering with proper DNS functionality resulting in intermittent resolution problems. So that's something you may want to check with a netstat -bn which shows you what programs are using which ports. DNS uses UDP port 53.
My Dell XPS M1210's Windows Experience Base Score in Vista
I've loved my laptop since the day we met. If you are in the market for a fast, lightweight, decent looking computer, you too may be happy with a Dell XPS M1210. As I mentioned in some previous posts, my machine has the following specs: Core 2 Duo 2Ghz with 4MB onboard cache, 2GB RAM, 7200 RPM 80GB HDD, 256MB nVdia card and no webcam (It was too unattractive). The mailing scale at work tells me that this all comes in at 4.5 pounds, give or take some quarter ounces.
I'm currently using Vista Enterprise and the Windows Experience Base Score is a 3.3. The average score, however, is 4.2.
| Windows User Experience Base Index | |
| Processor Calcs per sec. | 4.9 |
| RAM Memory Operations Per Sec | 4.5 |
| Graphics | 3.6 |
| Gaming Graphics | 3.3 |
| Primary Hard Disk | 4.8 |
The performance is incredible (SuperPI calculates 1 million digits in 26s) and it's quiet, sturdy and the cooling system is awesome. My employer called a few weeks after I bought it to tell me I could pick up a Dell 420 but I passed with no regrets. I haven't been this happy about a laptop since I got a SuperSlim PCG-N505VX back in 1999.
Anyone have these results from a Macbook Pro or Regular? I'd be interested to see what they report.
UPDATE: danboe.net released his scores. The regular seems to be about the same speed as mine. The Macbook Pro's score kicked ass all around though.
A Very Geeky April Fools
Back on April 1st, 2004, I was dating a woman who was a fan of Showtime's new lesbo show, The L-Word. She subscribed to Showtime specifically for the show but missed it one night. Not having experienced the pleasures of TiVO, she asked me to download a copy from the Internet. She was usually a little too paranoid to participate in P2P but was pretty desperate to see the missed episode. I hopped on her computer, installed the popular P2P client of the month and quickly downloaded the episode. She was happy but also a little concerned. I reassured her saying that there are millions of downloaders and only thousands of law suits, stats are in her favor.
I'm a bad person, I'll admit. Seeing her worry about the download got me thinking. Today is April 1st, what a perfect day for an awesome prank. As she hopped into the shower, I hopped onto her monster Dell laptop and began flipping through all of her IE Favorites. I gathered up all of the hostnames (imdb.com, news.google.com, nytimes.com and so on), opened up her HOSTS file and went to town giving about 50 of those hostnames the IP for my webserver.
I then setup my webserver to accept wildcard hosts and then copied all of the HTML from http://www.mpaa.org/anti-piracy/index.htm and inserted a fake message. The message, which had her full name (only after a successful IP check), stated that she was to be served with papers on Friday, April 2nd. I didn't want to make it too obvious that it was me so I actually setup a scheduled task to switch out the good HOSTS file with the modified one (as well as an ipconfig /flushdns) at the time I was in the shower. Oh, I also set the 404 as the index file in the event that she didn't go to the root URL. I tried to make the text as cheesy and unprofessional as possible and came up with the following:
The plan worked perfectly, when I was in the shower, my lady companion loaded up imdb.com, saw the message and shit her pants. She started sweating and ran into the bathroom. "CHRISSSSSSSY! I'm going to throw my laptop out of the window!! Oh my god oh my god!" I said "What's going on? You have a virus or something? Let me look. I'll be out in a second." "Noooo! My family is going to kill me! I'm getting sued!"
The bad person in me let her freak out for about a minute more as I fake comforted her, saying that it had to be something else. "The MPAA can't take over people's laptops -- it's illegal and virtually impossible." "WELL! LOOK!" she yelled. I strolled over to her laptop, poked around and said "Sweetie. The only problem with your laptop is that you've got a crazy girlfriend that replaced the HOSTS file and played a prank on you. APRIL FOOLS!" I then proceeded to run out of the room yelling bloody murder as she ran after me yelling profanities. Talk about a hoot!
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