Disable IPv6 in Ubuntu 8.04

May 19th, 2008

Some may find that out-of-the-box, Hardy Heron’s network performance is painfully slow. By default, IPv6 is enabled, and chances are good that your nearest router can’t speak the language nor interpret DNS requests efficiently.

To disable IPv6, open a shell and append the following to /etc/modprobe.d/blacklist:

# disable ipv6
blacklist ipv6

Reboot.

To verify that IPv6 is disabled, run

lsmod | grep ipv6

ip a | grep inet6

The commands shouldn’t return any information. Firefox browsing speeds should be much improved.

About Benjamin Perove

Benjamin has been associated with computer technology starting from a very early age, and has contributed to the success of many businesses and enterprises since 2001. He loves to crush pow at Keystone, play acoustic guitar, climb rocks, and ascend mountains on his road bike. Benjamin is an Avalanche fan and currently resides in Boulder, Colorado.

11 Comments so far

Corey @ September 26th, 2008

It works!
Desactivar IPv6 en Ubuntu Â» rm-rf.es @ October 8th, 2008

[...] Fuente original: Benperove.com [...]
Graham S. @ October 16th, 2008

A lot easier than I thought it would be, thanks!
softly.lt blogas » Blog Archive » Kur tas ipv6? @ January 13th, 2009

[...] DNS serverio AAAA užklausų išsprendimas tikrai nėra daug lėtesnis už A tipo, kaip kad sklando visokie gandai [...]
softly.lt užrašai » Blog Archive » Kur tas ipv6? @ July 22nd, 2009

[...] DNS serverio AAAA užklausų išsprendimas tikrai nėra daug lėtesnis už A tipo, kaip kad sklando visokie gandai [...]
MIke S @ August 12th, 2009

Which blacklist file, I have the following:
blacklist-aht_pci.conf
blacklist.conf
blacklist-firewire.conf
blacklist-framebuffer.conf
blacklist-oss.conf
blacklist-watchdog.conf

Thanks,
Mike
dogafin @ September 15th, 2009

i couldnt edit blacklist file, and cant run nautilus, any way to change permission on the file?
Ben @ September 15th, 2009

Mike S,

In newer versions of Ubuntu, the file you need to modify is blacklist.conf.

Dogafin,

Give this a shot:

sudo gedit /etc/modprobe.d/blacklist

Enter your super user password and you should see the file open. If you don’t know the password, type:

sudo passwd root

Enter the new password twice, then try to open the blacklist file.
Max Wyatt @ March 9th, 2010

Using /etc/modprobe.d/blacklist.conf to disable ipv6 doesn’t work on 9.10. Furthermore, IPv6 doesn’t seem to be loaded as a module at all. I an only assume it’s built into the Kernel. I use Linux so I can control my environment rather than having it handed to me, I don’t like this at all.
Ben @ March 9th, 2010

Hey Max, last I checked the title said 8.04, not 9.10. Sorry I haven’t updated lately.

To disable in 9.10, modify /etc/modprobe.d/aliases:

alias net-pf-10 off ipv6

Save, reboot.

Thx for the comment.