mail Routing is a feature of cPanel that allows you to manage how and where emails will be sent to your domains.
Note: if the MX input is not functional, this setting will not be effective* Local mail server: the server will always accept emails for this domain, delivering the messages to the inbox;
* Back up the message server: the server will act as a backup, receiving messages until a lower priority MX is available;
* Remote mail server: the server will not accept emails for this domain, sending all messages to an external server;
After selecting the desired option, just click on change, the selected option will always appear in bold.