On 01 Jan 2020 at 10:32p, Phil Taylor pondered and said...
 
 PT> I am using the current version of Mystic BBS running under Linux. Is the
 PT> SMTP mail server only able to send mail to the local users only?

Mystic BBS offers a SMTP server that allows a sysop or user to configure an
email client so that it can connect to the BBS in order to send BBS email.

To clarify: BBS email is private one to one email between BBS users. It's
accessed when logged in to the BBS by using the MC and MW menu commands. This
email resides solely within the BBS and is not (at this point) external email
that you can send via the Internet to someone else using a typical email
address.

The default port for SMTP is 25 but this can be set to something different if
you wish. 

--- Mystic BBS v1.12 A43 2019/03/03 (Windows/32)