"Some Internet Service Providers (ISPs) require VLAN in order for their modems to communicate with wireless routers. VLAN is not supported by Google Nest Wifi or Google Wifi and can cause your setup to fail.
Add a separate managed network switch (sometimes called a 'smart' network switch) with VLAN features.
- Connect your modem’s LAN port to the switch’s WAN port
- Connect the switch’s LAN port to your Google Nest Wifi routers or Google Wifi primary points WAN port
with an Ethernet cable.
- When finished, set up your Google Nest Wifi"