If you have a modem/router combo device, simply plug your gateway eero into the combo device and follow the setup instructions from there. In this case, you also have the option of putting your modem/router combo device into bridge mode, so it'll only act as a modem. For more, see this article.

I want to connect 2 Wi-Fi routers to create 2 separate Jun 27, 2020 How to Connect Two Routers & Have the Same SSID Having a second router means that you can get more ethernet ports, for example. I have two routers at home and this was the main reason why I wanted to set up the second router in the other room. But it was also because I needed USB ports over there. Can I connect two routers to the same network with - BluOS

Jul 04, 2019

Update the configuration of your DSL modem for Bridge Mode. For instructions for your specific … Router Bridge, Connect Two Routers – Router Behind Router May 21, 2014 Configuring a Second Router on a Static Network - dummies

The second router must be set up in client mode to utilize its full routing functionality, a mode that many home router’s don’t support. Consult a specific router model’s documentation to determine whether it supports client mode and how to configure it.

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