Can I enable rDNS (reverse DNS) via WHM?
It is important to note that the shared or primary IP address on the server usually needs an rDNS record configured for the server's hostname. By default, all emails will be sent from the server using the shared or primary IP address. If you need to determine if the rDNS record is already configured, please review the Email Deliverability documentation and the Email Deliverability interface in WHM.
In general, most cPanel & WHM users do not have the authority to edit their PTR records directly. Instead, some providers offer reverse DNS management in the service provider interface. Alternatively, you should contact your service provider to determine whether or not rDNS needs to be configured in WHM or from the service provider interface.
WHM does have the ability to create rDNS records. You should only do this if your nameservers are authoritative for rDNS records. Please review the below documentation URL for more information on how to configure the Reverse DNS record in WHM.