The smtp(s) ports 25, 465, and 587 have been opened in the firewall.
If I telnet mail.mydomain.com on ports 25 or 587 the 220 status is returned. However I get no response on port 465 so I assume that port is blocked or Postfix is not listening on that port (master.cf does include smtps settings although not seem ‘465’ specifically listed).
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