Comment 219 for bug 417757

I can confirm that there is something else, beyond IPV6 lookups, that is causing timeouts.

Kubuntu 9.10 with "libc6-i686 2.10.1-0ubuntu16 (i386)" which, if I'm not mistaken, contains the IPV6 fix.

Dell Nseries desktop box. Completely stock.

Using fixed IP behind a D-Link 707 consumer grade firewall. DNS server running on a CentOS 5 box on the other side of the firewall.

IPV6 disabled in /etc/default/grub using
   GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 quiet splash"

IPV6 disabled in firefox as well.

Regardless of whether I use a local caching nameserver, pdns-recursor, or a name server on a CentOS 5 box, the timeout phenomenon is the same. From a gut feel point of view, I'd say it's worse when using the local caching nameserver.

Running WinXP in VMWare Workstation 7 on the same physical machine with no timeouts. (i.e. While it's timing out in firefox I switch into XP and pull the same page. Comes up instantly.)

My feeling is we're dealing with some kind of race condition in the resolver library because it happens when doing a number of simultaneous DNS requests.

Open 20 or so tabs in firefox to various websites with varying load times. Close firefox. Reopen firefox and at the same time open Thunderbird. In this scenario Thunderbird will timeout 100% of the time as will the majority of tabs in firefox.

It's intermittent. In FF, I can have one tab that's loading and other that's timing out. Sometimes it will pull the main html page but timeout on graphics or CSS.

I would like to be able to run Kubuntu instead of having to fallback to CentOS 5. I am willing to lend a hand to track this down if you would like to give me some tests to run. I can reproduce this problem consistently.