@TIDBIT Hi, I'm not sure what MB means but one Ethernet port is to connect to the Internet, the second can be used for a local LAN connected device or devices behind an Ethernet switch. The WiFi...

@Ken_in_Boise It appears that the second port is "behind" the firewall as it's the same subnet as assigned to WiFi. The other port is upstream typically to your Internet modem or router.

@Matti I have a mesh system with Deco M5 devices. Connecting one LAN port to the Internet modem and configuring the local LAN (not really needed but I wanted to change the subnet) resulted in the...