Enabling IPv6 in CentOS Linux

Usually, IPv6 is enabled by default during installation. But there are times that we want to take control of things manually... just like enabling or disabling IPv6 support in CentOS Linux. Some folks out there may feel that they don't need IPv6 yet and so they turn it off. Some have disabled IPv6 by default during installation but suddenly become curious about IPv6 and want to explore it, I hope this article could be of help.

The IPv6 knob in CentOS can be found at:

/etc/sysconfig/network

If you open it and your system supports IPv6 then it will look like this:

NETWORKING=yes
NETWORKING_IPV6=yes
HOSTNAME=localhost.localdomain

If you don't see the "NETWORKING_IPV6=yes" in your "/etc/sysconfig/network" file, that means you have not enabled IPv6 yet. Or, if you have an IPv6 support and you want to turn it off, you just change "NETWORKING_IPV6" to "no".

You then need to restart your system for changes to take effect.