- sudo gedit /etc/modprobe.d/aliases
- Find the line: alias net-pf-10 ipv6
- Edit this to: alias net-pf-10 off
- Save the file and reboot
- Check ipv6. There should not be any output to any of the following commands.
ip a | grep inet6
lsmod | grep v6 - change network.dns.disableIPv6 to true in about:config of Firefox.