Disable IPv6

1. Edit the Grub config.

sudo nano /etc/default/grub

2. Append/edit the following line.

GRUB_CMDLINE_LINUX_DEFAULT="ipv6.disable=1 quiet" GRUB_CMDLINE_LINUX="ipv6.disable=1"

3. Update Grub.

sudo update-grub

4. Reboot for the changes to take effect immediately.

sudo reboot now