Connect with external gateway - (Newbie)

I installed the latest full image (chirpstack-gateway-os-full-raspberrypi3-20220914194126.rootfs.wic) on a rpi. I do not have a concentrator hat for the pi but I do have an external single channel gateway for testing purposes. I did add the gateway on the dashboard.
I connected the SCGW to the TTN cloud server and had full communication. Now I am trying to connect the SCGW to my rpi installation. I set the server address for 192.168.5.1:1700.
It would seem that the SCGW connects at network level but nothing further.
Is there anything more to do to get the gateway to connect.

I looked at the documentation but I think my questions are a bit to low level due to my inexperience with ChirpSTack.

This documentation might help you to debug your issue: Connecting a gateway - ChirpStack open-source LoRaWAN® Network Server documentation.