On Sat, May 12, 2007 at 09:03:41AM -0500, Dallas Clement wrote: > On Sat, 2007-05-12 at 14:27 +0100, Karl E. Jorgensen wrote: > > On Thu, May 10, 2007 at 09:41:59AM -0500, Dallas Clement wrote: > > > I'm getting terrible DNS lookup performance on my Debian Etch system. > > > I've installed the "Etch" - Official Beta amd64 version. > > > > > > After installing, I noticed that the Internet browsers were taking a > > > really long time to pull up a web page. I also observed that the > > > browser delays seemed to be DNS related as they were spending a lot of > > > time "Looking up whatever.com...". [snip] > This is what's in my /etc/resolv.conf: > > dallas@debian:~$ cat /etc/resolv.conf > search clements > nameserver 192.168.0.1 > > 'clements is the name of the local domain. And that is the correct name > server on the local domain which happens to be a D-link router. It uses > DNS relay to forward DNS requests to my ISP. > > Interestingly, if I repeat the dig test directly on my ISP DNS server > address, the time between queries is dramatically reduced: [snip] > real 0m0.157s > user 0m0.004s > sys 0m0.000s > > WOW! And if I directly edit the /etc/resolv.conf and put in the DNS > server address of my ISP instead of my relaying D-Link router, lo and > behold, my web-browsing is incredibly fast!!! I think we can safely > conclude that the problem lies with my router and slow DNS relay. > Though I must say that I am a bit mystified as to why Windows is so fast > if it presumably relies on the D-link router for DNS relay also. "presumably" - I suspect not. At least that would make for a natural explanation... Another possible explanation: Do you have a firewall on the linux box? If so, try disabling it. My rationale? If the firewall gets in the way of udp:53 but not tcp:53, I'd expect the same 5-second delay, as the resolver first tries udp and then falls back on tcp... (perhaps windows "remembers" that udp failed and then plods on with tcp?) It might be worth double-checking the firewall settings on the router. Sounds like they're OK, but a quick browse is in order... > I wish there was a way to keep my ISP DNS addresses in > the /etc/resolv.conf file permanently. I think they get overwritten > after getting a DHCP response. Can't the router be reconfigured? > Thanks for the help. No problem -- Karl E. Jorgensen karl@jorgensen.org.uk http://www.jorgensen.org.uk/ karl@jorgensen.com http://karl.jorgensen.com ==== Today's fortune: The more crap you put up with, the more crap you are going to get.
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