TP-Link Deco M4: a four-floor wired-backhaul setup

As the title suggests, my home is not very large, but it has four floors including the basement. To provide whole-home Wi-Fi coverage, avoid switching to a different Wi-Fi connection on each floor, and maximize the Wi-Fi signal at the same time, I spent a long time researching and finally chose TP-Link’s entry-level Deco M4. I decided to use the most stable wired-backhaul connection mode. I finally connected the home network last night, so I am recording the process here in case I forget it later.

Equipment: one Deco M4 and one switch on each floor, counting the basement as a floor.

Background: the network trunk enters in the basement. Each upstairs room has a network wall panel, but each panel has only one network port.

Key points

1. First, I connected one Deco in the basement to the main router and added it in the Deco app, setting it as the main Deco.
2. Then I took each floor’s Deco, also called a satellite Deco, to the basement and added it to the main Deco in the Deco app without connecting it to the main Deco with an Ethernet cable first. This is very important. I used wireless mode in the Deco app to add these Decos to the network. Only then did I connect the main and satellite Decos directly with Ethernet. After about one minute, the Deco app showed that the connection between the satellite and main Deco was wired. That satellite was now configured, so I could take it upstairs and connect it to a network wall panel. Through the basement switch, it connected to the main Deco using wired backhaul.
3. I repeated this pairing process until every floor’s satellite Deco had successfully paired with the main Deco over Ethernet, and then the setup was complete.

4. The connection status was as follows:

   In the basement: one port on the main Deco was connected to the main router, and the other port was connected to a switch. The switch was connected by Ethernet to the network wall panel in each upstairs room.

   In the upstairs rooms: each satellite Deco was connected by Ethernet to a network wall panel.

5. However, because each room had only one network port, connecting the satellite Deco occupied it, so my computer could only use the wireless network broadcast by the satellite Deco. Although the satellite Deco also had two ports, one was already connected by Ethernet through the wall panel and switch to the main Deco in the basement, and the other port could not pass the network signal. In other words, the satellite Deco could not be used as a switch in my setup, and connecting an Ethernet cable from the satellite Deco directly to the computer did not provide Internet access. Only the main Deco could be used as a switch, so I also needed to add a switch in each room alongside the satellite Deco. The computer and satellite Deco could then both be connected by Ethernet through the switch to the main Deco in the basement. In this way, one satellite Deco plus one switch on each floor provided both wired networking and Wi-Fi.

The images show a process summary that I asked GPT to prepare, along with the status icon displayed in the Deco app when the connection uses wired backhaul, shown in the last image.