How to disable IPV6 on centos 6.x

The following procedure worked for me.

1. Add the following lines in the files listed below:

% vi /etc/modprobe.d/modprobe.conf

options ipv6 disable=1
alias net-pf-10 off
alias ipv6 off
install ipv6 /bin/true

% vi /etc/sysconfig/network

NETWORKING_IPV6=no
IPV6INIT=no


% vi /etc/sysconfig/network-scripts/ifcfg-ethx (x=0, 1, 2 …)

IPV6INIT=no



2. Disable ip6tables service

chkconfig ip6tables off



3. Reboot your system

init 6 or reboot

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There is a step 4 at the website which mentions to rmmod ivp6, but I didn't need to do that.

Referenced:
http://mikent.wordpress.com/2012/02/04/how-to-disable-ipv6-on-redhat-6-x/