I was finally able to get it to work. Both tested in the Standalone and under Omada Controller. I don't understand why the WebGUI has to be IP and not allow FQDN. Anyway I had to find the IP address...

@NetworkingInNH LAG can be either Static or Active. According to the TPLink employee's reply, the EAP783 it only knows Static. an Active LAG is LACP (802.3ad) but both end points must know 802.3ad....

@JackShepard Thank you for the heads up. I am about 2wks into my 30days refund period and there are quite a few things that isn't sitting well with the ER8411. How long have you been waiting for?

for some reason my SG2008P complete the "Inform URL/IP" with bunch of stuff behind it. Is this normal? My ER8411 doesn't do that... but the SG2008P just keeps adding the rear part. Anyway, my SDN...

I figured out the last part as well. I guess it was just easier to do it in CLI than trying to figure out the WebGUI. (although, I really wish the CLI is more Cisco-like) Anyway.... to fix my issue I...

Okay I have figured out why it wasn't trunking. For whatever reason it needed a native vlan setup. meaning that it wants to pass untagged packet across the trunk. Cisco calls it native vlan. this is...