Slow DNS in Kubuntu -- Fixed

[Peter Stoddard]

Hi folks

I have fixed a problem with slow DNS lookups on my Powerbook   In trying to 
solve the problem I found several people reporting the same problem, but I 
never saw any answers that worked for me.  

Short description:  
DNS works fine on my Mac OSX boxes because I can add the DNS IPs to the 
Network Control Panel, but when I loaded Kubuntu, DNS slowed to a crawl.  
That was because adding them to the Breezy Kubuntu Network Control Panel 
or /etc/resolv.conf didn't work, and I had to enter the IP numbers into the 
router configuration file to fix the problem.

Long description: 
I have a DSL line which I lease through Earthlink, and a Netopia DSL Modem 
hooked up via ethernet cable to an Airport Extreme wireless router.  I'm glad 
the router has an open ethernet port because my airport (wireless-Broadcom) 
card isn't recognized by Breezy..  :<  The computer is connected by ethernet 
cable to the wireless router.

I have a couple of Macs which have been accessing the internet for years with 
this setup with no problem.  The problem came when I installed Kubuntu Breezy 
on an extra powerbook.  On this machine, DNS lookups happened, but they were 
very slow, and that slowed everything down, from mail with Kontact to 
internet browsing with Konqueror.  I loaded Firefox, and it was slow too.

In trying to solve this problem I first connected my computer directly to the 
internet with a crossover cable, bypassing the router.  DNS look up and 
browsing speeds returned to normal.  Hooking the computer back up to the 
router with a straight-through cable slowed DNS down again.

NAT portmapping protocol is available only to computers using Mac OSX 10.4, 
and one of mine is still running 10.3, so NAT is not enabled on the wireless 
router.

I tried to set the standard earthlink DNS IPs in /etc/resolv.conf and in the 
"System Settings:Network Settings" gui, but I found out these have no effect 
on browsing speed.  In fact, these settings get reset every time the computer 
is rebooted.  Rude.

Throughout all this, pinging google.com has been pretty fast, and remained the 
same no matter what the setup was.

Finally I went into the Internet panel of the Airport Base Station and entered 
the Earthlink DNS IPs there.  That solved the problem.  The Macs had been 
able to pass DNS queries to the Earthlink server because I had entered the IP 
numbers in the Mac OSX Network:Airport:TCP/IP control panel.  Entering the 
same information in the corresponding Kubuntu control panel or 
in /etc/resolv.conf didn't work.

So there is the solution to my problem, and I hope it may help some other 
Mac-Kubuntu converts too.

Pete