How to Disable IPv6 on Linux Operating System

Red Hat-based distributions

1. Open a terminal window.

2. Change to the root user.

3. Type these commands:

sysctl -w net.ipv6.conf.all.disable_ipv6=1
sysctl -w net.ipv6.conf.default.disable_ipv6=1
sysctl -w net.ipv6.conf.tun0.disable_ipv6=1

To re-enable IPv6, type these commands:

sysctl -w net.ipv6.conf.all.disable_ipv6=0
sysctl -w net.ipv6.conf.default.disable_ipv6=0
sysctl -w net.ipv6.conf.tun0.disable_ipv6=0
sysctl -p

Debian based distributions

Here’s how to disable the protocol on a Debian-based machine.

1. Open a terminal window.

2. Type this command:

sudo nano /etc/sysctl.conf

3. Add the following at the bottom of the file:

net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1
net.ipv6.conf.tun0.disable_ipv6 = 1

4. Save and close the file.

5. Reboot the device.