RHEL/CentOS:
* In /etc/modprobe.conf, make sure you have
alias net-pf-10 off
alias ipv6 off
* Reboot.
• RHEL/CentOS/Fedora Core (method 2)/Mandriva (method 1):
* In /etc/sysconfig/network, add a line
NETWORKING_IPV6=”no”
* Reboot.
Reference:
beranger.org