dovecot - Sep 2017 - Share Website certificate with SSL/STL Dovecot IMAP and Postifix SMTP

Marco Marco writes writes:
> I've bought a certificate from the authority for my website to use to
> access in https mode.
>
> Is it possible to share the same pairs to authenticate the emails sent
> by postfix and Dovecot in order to avoid that client as Hotmail.it or
> Gmail intercept these as Spam?
By "same pairs", I assume you mean key and certificate.

Yes, just as long as you use the same Subject for all your services (e.g.
"mail.yourdomain.com") or you have purchased a wildcard certificate
e.g. "*.yourdomain.com" to authenticate
"webmail.yourdomain.com",
"imap.yourdomain.com", "smtp.yourdomain.com", etc.)

Certificates do not authenticate services or protocols, but server names
(typically).

Joseph Tam <jtam.home at gmail.com>