How to host your blackjack email server for different domains?

Question

Email

How to host a blackjack email on the same server that hosts the site itself -- I know, more or less. There is an article on Habré.
But, if there are many domains, how do I set up my blackjack email on the main server so that I can both receive and send emails for all my domains? Which are hosted on other servers.
Yandex, google ..... -- I don't use it, the question is how to make your own decision.

PS
What kind of people - you write, highlight in bold, they still do not see?

Answer 1

SMTP server to send and receive mail + IMAP server to read it. Up to the heap, you can keep DNS primary here, and give the secondary to some thick server like nic.ru.