Cisco ASA - Allowing external access to a secure server via RDP

Solution 1:

Well, the NAT rules don't seem to be correctly set up. The port forwarding concept for Cisco ASA is a bit tricky:

Port Redirection (Forwarding) with Static

Port forwarding or port redirection is a useful feature where the outside users try to access an internal server on a specific port. In order to achieve this, the internal server, which has a private IP address, will be translated to a public IP address which in turn is allowed access for the specific port.

So, for port forwarding to an internal server threre are two steps you will need to take:

1. Translate the internal server IP, 10.11.200.55 on port 3389, to the public IP address, x.x.x.x of your ASA at port 3390.
2. Allow access to the public IP, x.x.x.x on port 3390.

Detailed step-by-step instructions are available on Cisco site: Port Redirection (Forwarding) with Static