As of now I only have port 22 open in the router. I use terminal to connect to the remote server and forward a port:
ssh -L 6900:127.0.0.1:5900 email@example.com
Now I setup vine viewer to connect to localhost on port 6900. This works fine and only needs port 22 open on the router.
I read your manual about using ssh. I don’t understand why I would need to open ports 22 and 5900.
Maybe someone can explain to me how Vine Viewer works to connect using ssh?