How-To Disable IPv6

Introduction

If your server has broken IPv6 networking, this can lead to issues such as backup destination validation timeouts. This article will assist you with disabling IPv6 on your server.

Please note that cPanel software support cannot modify your server's network on your behalf. It is recommended that you have the steps mentioned in this article carried out by a system administrator.

Procedure

1. Access the server's command line as the 'root' user via SSH or "Terminal" in WHM.
2. Open /etc/sysctl.conf in your preferred text editor.
3. Add the following lines to the file.

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

4. Save the changes and exit the text editor.
5. Run the following command to enable the settings.

   sysctl -p

If you remove the kernel modules for IPv6, your operating system will generate warnings in cPanel & WHM, may prevent account creation, and may cause service failures.

Additional resources

IPv6 Server Administration