Forwarding a single port from one network adapter to another? I have a Parallels Desktop virtual machine with Host-Only networking. I want to set up Remote Desktop on Windows (port 3389) while not exposing any other part of Windows to the external network. Parallels adds a virtual network adapter that allows me to communicate with the Windows machine. On OSX I tried to add the following rule:

sudo ipfw add 100 fwd ,3389 tcp from any to 10.37.129.3 dst-port 3389


But it doesn't seem to work. Is there anything wrong with my rule? Is there another way of doing this?
According to what you're trying to achieve, your rule is in a wrong position.

This Source will show you how to set up a rule.
However, you're navigation FROM:


  sudo ipfw add 100 fwd 10.37.129.3,3389 tcp from any to any 3389 in


Please don't hit me with a stick, I'm unable to forward this on my Mac to test.