@newmoro 

This behavior is not normal and may be caused by loss of Ethernet link between the switch and Main Deco. If you power off Satellite Deco that is connected over WiFi and that forces another Satellite Deco connect over WiFi instead of Ethernet, this is the proof.

See this forum topic for similar situation: https://community.tp-link.com/en/home/forum/topic/655034

Thanks for the quick response.

I followed your suggestion and replaced the Ethernet cable between the main Deco and the switch. I tested with two different cables, including the one that came with the Deco units. I also tried switching the port on the switch.

After each change, I restarted the main Deco unit to ensure proper reconfiguration, but the issue persists, as shown in the image below.

I’d like to note that the switch is functioning perfectly, as other devices connected to it are working without any issues.

What else can I try to ensure that all Deco units are properly utilizing the wired backhaul connection?

I appreciate your support and any additional troubleshooting suggestions.

  @newmoro 

What is the switch brand and model number?

This is what you can do:

1. Power off Satellite Deco that is connected by WiFi. Restart another Satellite Deco and check after the restart how it connects: by WiFi or Ethernet.

2. If after restart that remaining Satellite Deco connects by WiFi, power it off and with both Satellite Deco offline check again if other devices wired to that switch still have Internet access.

Switch Information:
The switch I am using is the one integrated with my fiber link. It has four Gigabit ports, and I can confirm that all of them are fully functional. I tested each port with my laptop, and they all provided a Gigabit connection without any issues.

Switch Information:
The switch I am using is the one integrated with my fiber link. It has four Gigabit ports, and I can confirm that all of them are fully functional. I tested each port with my laptop, and they all provided a Gigabit connection without any issues.

Steps Taken:

1. Test with One Satellite Deco Powered Off:

   • I powered off the Deco unit in the bedroom (the one currently connected via Wi-Fi), and the other Deco unit, which was previously using a wired connection, switched to Wi-Fi instead, as shown in Image 1 below.
      

Image 01

 

• Cable Replacement:

  • I replaced the cable for the main Deco unit once again, but the issue persists.

• Reconnecting the Bedroom Deco Unit:

  • After turning the bedroom Deco back on, the setup returned to its previous state, where it connects only via Wi-Fi, as shown in Image 2

With both satellite Decos turned off, I checked if other devices connected to the switch still had internet access, and they all worked without any issues.

What further steps can I take to troubleshoot this?

Thanks for your continued support!

  @newmoro 

It appears that Satellite Deco can't communicate with Main Deco through the switch, for reason yet unknown.

Take a look at three examples of Network diagram and tell which corresponds to what you have. If nothing matches your home network, you'll need to provide more details on it.

  @newmoro 
What is the operation mode of your Deco mesh: Router or Access Point?

How is your main Deco connected to Internet?

Is your ISP box connected to the switch?

  @yves_b 

 

Thank you Yves and Alexandre for the great support!

I changed the operation mode to Access Point, and now everything is working perfectly, as shown in the image below.

I really appreciate your excellent assistance!