Xiaomi Mesh System AX3000 Benutzerhandbuch Seite 5

Mesh Networking
Place the other router in the room that needs Wi-Fi coverage.
Power on the router, and wait for it to work normally. Then it
will automatically complete the wireless networking as a
satellite router.
* You can also use the network cable to connect the satellite router's
WAN port to the main router's LAN port, and the networking will be
automatically completed a erwards.
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