>From: Stackpole, Chris [mailto:cstackp...@barbnet.com] >Sent: Monday, June 15, 2009 4:36 PM >Subject: RE: DNS lookup problems after upgrade from Etch to Lenny > >> From: Stackpole, Chris [mailto:cstackp...@barbnet.com] >> Sent: Monday, June 15, 2009 4:30 PM >> Subject: DNS lookup problems after upgrade from Etch to Lenny >> >> Hey guys, >> >> I have been trying my best to figure this out recently but not having >> much luck. I am hoping someone here might be able to help. >> >> We had an Etch box that had been running great for almost 2 years. >> When we decided that we really should upgrade to Lenny, the box had >> over 300 days of uptime. It was a really solid box that handled a ton >> of data for us. >> >> There are a number of reasons, but we needed to update the system. So >> I ran the upgrade process. I did an `apt-get update` and `apt-get >> upgrade` on Etch, restarted, changed out sources to Lenny then did an >> `apt-get dist-upgrade`. Standard and simple and everything seemed to go >> really well. >> >> However, shortly after, it started slamming our DNS servers. It went >> from an average of 3.5 requests per minute to over 7000 requests per >> minute. Every time it talks to a system, it does a DNS lookup. > > Scratch that bit. My network guy just sent me the official numbers. It > jumped from 3.5 requests per minute to 73,955.25 requests per minute. A > factor of 10 worse. :-0 > >> At first I thought it was Apache and or the applications we run, but >> after some testing, I don't think that is the case. I stopped all the >> programs and apache before I started pinging other systems by their >> domain name. It constantly asked the DNS for information. >> >> How do I know? I am running `tshark -f 'port 53'` and watching all the >> data in real time. When I ping a name, it does a lookup. If I leave >> the ping running, after a few seconds it asks again. I set up a loop >> using `ping -c1` and no matter how fast the loop ran, it asked for the >> name every time. >> >> So a busy server working with ~50 other computers and tons of >> connections is asking the DNS for every connection! >> >> Can any one help out? I am digging around in all sorts of conf files >> but not finding anything. My search online seems to suggest I should >> install a DNS caching utility, but I don't understand why I have this >> problem. >> >> I didn't have it before and on another system running a fresh build of >> Lenny running the exact same software handling a similar load and its >> DNS ask rate is just as low as it was on this system running Etch. >> >> I am at a loss. I appreciate any help people can give. >> >> Thanks, >> Chris Stackpole
Well I can't seem to find and fix this problem. So I guess my two options are: 1) rebuild the system using Lenny 2) Install a DNS caching utility. Right now I am trying number 2. I installed dbndns and tied to configure it using this [1] talk as a guide, but I think I goofed something up. It isn't working. Can anyone help out in configuring this? Thanks, Chris Stackpole [1] http://bevilacqua.us/talks/djbdns/ -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
