Forwarding openvpn traffic
I setup openvpn server on my router, to enable secure surfing from any place away from home. The tutorial I used is here: https://doc.pfsense.org/index.php/Routing_internet_traffic_through_a_site-to-site_OpenVPN-connection_in_PfSense_2.1
All traffic received over the openvpn tunnel is forwarded correctly. The tun interface used and created by openvpn is in another network segment than the router.
My question is: can I reach my pfSense interface? I suppose that would be possible with a firewall rule, but how do I go about?
You can browse direct to the pfSense in tunnel ip address, it is listening.
You will need a Firewall / Rules / OpenVPN allow access to self (same as anti-lockout rule on wan)
From the example you list it would be https://192.168.204.1
You should also be able to browse to the pfSense inside LAN address https://192.168.20.1 from example.
The server side router knows how to get to all of those addresses, as seen in Diagnostic / Routes.