I've got a vps that I'm wanting to tighten down its webmail setup.
Currently it's running php 5.6 and it does have the openssl extension
loaded. It's got apache 2.4 and that hooks in to php via php-fpm. I'm
running Postfix and Dovecot and Roundcube 1.3.6.
What I'm wanting to do is tls-encrypt all server communications from
roundcube to the various imap/smtp servers. I've got letsencrypt
providing my server certificates. In my roundcube configuration I've
got a map pointing: