Changing Your Server’s Host Name
You specify your server’s host name during your very first login to Plesk. If you want to change the host name later, you can do it through Plesk.
Note: Specifying an invalid host name will result in unpredictable Plesk behavior and server malfunction. The host name must be resolvable from the Plesk-managed server, especially if Customer and Business Manager is installed.
To change your server’s host name:
Log in to Server Administration Panel.
Go to Tools & Settings > Server Settings.
Enter the new host name in the Full hostname field.
This should be a fully qualified host name, but without an ending dot (for example,