Given that Client A and Client B are using OpenVPN and they are on the same virtual network. A connects to B via e.g. SSH. In front of B there is an external Firewall or whatever.
Is the traffic which is monitored by the firewall actually addressed to port 22 then? So is it port 22 B should enable or is it more like the VPN port?
To take it short: am I right that all traffic from and to the VPN is "tunneled" via a single Port and therefore only this single ports needs to be open?