Since I don't own a GS-device, I'm not sure if you can do that.
The GX20 can be accessed thru a LAN connection directly (prior or after initial setup), by entering the local IP in a browser. Username would be the Serial-Number of the device, password isn't required. This leads to a basic setup-page where you can set Internet-Connection-type and port-management (disable/enable).
Maybe the GS offers something similar?