Hi,
I have a D-link 2730U modem-router which is not supported by OpenWrt so I installed it on a Nanopi Neo h3. I deleted my internet connection on D-link and created a bridge on it instead. You can see it here:
Nanopi with its only ethernet interface is connected to D-link. As you can see, the problem is, WAN always returns some errors. The first one is Unknown error (USER_REQUEST). The others are Unknown error (AUTH_TOPEER_FAILED) and Unknown error (NEGOTIATION_FAILED).
I'm new to this and I don't know what to do. Also, I'm not even sure about my configurations and I have no idea how to test it! The question is what should I do now? How can it be done?
I am not sure you can have WAN and LAN on the same interface, or how to make it work without VLANs.
I would review the configuration on the modem/router, including how it connects with the server. On the router, I would also see a complete log on the connection attempts.
The single port configuration described for e.g. a TL-WA703N uses the wifi interface for the lan. Your board doesn't have wifi so you would need to set up what is called a "one-armed" router. There VLANs run on the Ethernet port and an external VLAN-capable switch is used to separate them to the modem and to the LAN devices. It would be simpler to buy a device that has two ports.
Those messages indicate the router is not reaching a server at the other end of the connection. Please, show us the config page for the connection on the modem.
Sorry, I meant that page but configured to connect from the modem. I want to see how is the connection configured on the modem, and see if there are any differences to your current configuration on the router.