Postfix Virtual Mailbox Domains vs DNS ?
There are several tutorials about Virtual Mailbox Domains but none of them explains how to setup DNS or at least such a phrase "there is no need to setup DNS".
Use case: the MX of mydomain.com is "MX 10 mail.mydomain.com", and I created two additional virtual domain mydomain2.com and mydomain3.com in the main.cf of Postfix.
Do I need to enter some information about these virtual domains in the DNS of mydomain.com?
If the answer for the question above is "No, you don't", then can I create any virtual domain I want even domains already exists?
Thanks in advance.