While I was cleaning up my Ubuntu Email server configuration, I consolidated my login security. My SMTP server is Exim and my IMAP server is Dovecot. Mail User Agents (MUAs) use authentication over TLS encrypted connections to access IMAP and SMTP. Both programs had their own password configuration.
Exim includes Dovecot in its supported authentication mechanisms. This enables one authentication mechanism to be used for both SMTP and IMAP (or POP3). This post also includes configuration details for forced authentication over the Submission port. Continue reading