How to disable IPV6 on RedHat 6.x

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

/etc/modprobe.d/modprobe.conf

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

(for Redhat 5.x, file location is /etc/modprobe.conf)

/etc/sysconfig/network

NETWORKING_IPV6=no
IPV6INIT=no

/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

or

shutdown -r now

4. Once your system if fully started:

rmmod ipv6

5. Make sure ipv6 module is not loaded

lsmod | grep ipv6