POP3/IMAP reverse proxy at DMZ
i hope somebody could help me with a small configuration. We have a Zimbra server inside the LAN to provide webdesktop and POP3/SMTP services for the corporation. But we are planning to provide this services to the outside through a reverse proxy on the DMZ. The reason of using a proxy is for, 1. security reasons, 2. load balancing in the future for more than one email server.
For web reverse proxy, there is plenty of information on internet, above all apache2 (http and https), but i am seeing that apache2 doesn't support email reverse proxy capabilities, so i will have to think about using NGINX for proxying, at least, Email. The only issue is that there is no information for Zimbra about how to configure a reverse proxy for SMTP/POP3.
Could someone provide some kind of wiki, howto or doc that could enlighten me?
thank you very much in advance.