I have a router configured to send all the incoming traffic to a single reverse proxy machine.
This machine hosts Nginx which forwards the traffic to different servers, based on the domain name. For instance, http://a.example.com/ is forwarded to server A, and http://b.example.com/ is redirected to server B.
How do I do the same thing for Remote Desktop connections? In other words, if I have servers C and D hosting Windows, how do I connect, outside the network, to server C through c.example.com:3389 and to D through d.example.com:3389?