Disable IPv6 networking on CentOS

Follow these steps to disable IPv6 on CentOS. Edit the /etc/sysctl.conf file, I will use the nano editor here:

nano /etc/sysctl.conf

And add the following line at the end of the file:

net.ipv6.conf.all.disable_ipv6 = 1

Then run:

sysctl -p

to load the new settings.

The next step is to edit the network card configuration file (/etc/sysconfig/network-scripts/ifcfg-eth*) and add or edit the setting IPV6INIT so that it is set to "no".

IPV6INIT="no"

Now edit the file /etc/sysconfig/network:

nano /etc/sysconfig/network

And set the NETWORKING_IPV6 option to "no":

NETWORKING_IPV6=no

Then restart the server.