Server is inaccessible once rebooted after installing the cPanel software

Symptoms

After installing cPanel on AlmaLinux/CloudLinux/Rocky 8 servers, your server becomes inaccessible when rebooted.

Description 

The NetworkManager service is disabled on AlmaLinux/CloudLinux/Rocky 8 servers upon installation of the cPanel software. The Network service will be installed and configured in its place. Customizations to the network-related configurations can conflict with this server change and prevent the Network service from starting during server boot. If such a conflict occurs, rebooting the server will result in the server being inaccessible. 

Since the cause varies depending on the customizations causing this, the only workaround that we can confirm is to re-enable the NetworkManager before rebooting the server after a cPanel installation.

Workaround

You will need to work with your network or system administrator to configure the server to be compatible with the Network service. By default, this will work with stock images of these operating systems and will only occur if customizations have been made to them. In some cases, you may need to contact your hosting provider for further assistance. 

1. Access the server's command line as the 'root' user via SSH or "Terminal" in WHM.
2. Disable the Network service.

   /usr/bin/systemctl disable network

3. Enable the NetworkManager service.

   /usr/bin/systemctl enable NetworkManager

4. Stop the Network service and start the NetworkManager service.

   /usr/bin/systemctl stop network; /usr/bin/systemctl start NetworkManager

5. Reboot the server.

   shutdown -r now

Additional Resources

What are the networking requirements for a cPanel installation?