If you only have one LAN network created on Firewalla Gold and you want to isolate one device from talking with other local devices in the network.
Here are some recommended configurations:
Option 1: Create a dedicated separate network in Gold and connect the device you'd like to isolate to it. On that network, block traffic from and to Local Networks.
Option 2: Physically connect the device directly to a LAN port of Gold to force all traffic routing through Gold even if they are in the same network. Then block traffic from and to Local Networks on the device.
Note: This configuration below will NOT work:
ISP -> Gold -> Switch -> Device 1
-> Other Devices
Device 1 and other devices can communicate without routing traffic through Gold (only through the switch), so blocking rules won't work.