I don’t need IPv6 on my internal servers and workstations, however now all distro’s seem to be shipping with IPv6 enabled by default.
To disable follow these steps and see the reference sites for more info.
Debian:
To disable IPv6 change /etc/modprobe.d/aliases
# alias net-pf-10 ipv6
# Disable ipv6
alias net-pf-10 off
alias ipv6 off
Now comment out all IPv6 references in /etc/hosts and restart server.
References:
http://www.karkomaonline.com/index.php/2009/04/how-to-disable-ipv6-in-debian
http://www.linux.com/community/blogs/disable-ipv6-on-debian-lenny-quick-howto.html
Ubuntu:
Edit /etc/default/grub file
Change
GRUB_CMDLINE_LINUX_DEFAULT=”quiet splash”
to
GRUB_CMDLINE_LINUX_DEFAULT=”ipv6.disable=1 quiet splash”
Save and exit the file
Update the grub from the command line
sudo update-grub
Reference:
http://www.ubuntugeek.com/how-to-disable-ipv6-in-ubuntu.html
Update: This site has a better way for Debian:
http://www.cyberciti.biz/faq/disable-ipv6-on-debian-linux-lenny-squeeze/
Update for Ubuntu:
http://www.linuxarticles.org/2011/06/disable-ipv6-in-ubuntu/