I'm setting up a new server with the goal of using letsencrypt versus my self signed cert. (I'm also going to try those SpamAssassin alternatives that require less RAM.) So I will run two VPS for a period as I debug the new server.
That said, is there any way to implement email going to both example.com and mail.example.com. That is I intend the email servers to be different. Seems to me maybe Dovecot won't mind but I don't see this working with postfix.
Or should I just register a new top level domain for testing?
While I'm at it, is it suggested that email and Web use different certificates.