Ubuntu 7.10 (aka Gutsy Gibbon) has a DNS-related bug.
I referred to it when I posted about having upgraded to 7.10 last week but since then I have found how to get around it.
First the problem -
After the upgrade, browsers, mail clients and other Internet-related applications run very slowly. Loading pages in Firefox can take 30+ seconds and sending/receiving emails seems interminable too.
On inspection, the Network settings seems to forget any custom settings (I had pointed it at the OpenDNS servers). Adding the OpenDNS servers to the router’s settings didn’t help. Re-adding the DNS servers to the Network Settings helped for about five minutes when it would once again lose the configuration and slow down.
Checking the Ubuntu forums I discovered that this appears to be related to IPv6.
I tried the following suggestion and it fixed the problem for me straightaway:
- IPv6 is supported by default in Ubuntu and can sometimes cause problems
- To disable it, open a Terminal (Applications > Accessories > Terminal) and type the command: gksudo gedit /etc/modprobe.d/aliases
- Find the line alias net-pf-10 ipv6 and change it to read alias net-pf-10 off
- Reboot Ubuntu
Everything is zinging along happily on my laptop once more!