As I’m running many different Linux servers I’m always looking for new features.
Just today I found an article about SSLH. It allows you to run different services at one port, by identifying the data sent at the request.
This is a technique that I’m already using at my JAVA server where I run at one port HTTP server and my own protocols, because each of them identify it self by different but constant header.
It also looks to me as very simple way how to mask there there is actually running SSH or OpenVPN client at the server.