Devices cannot communicate in the same frequency and router
I have two X20 routers working in AP mode. If my device (laptop, phone, raspberry pi) is in 5Ghz network, I can only connect (either ping, ssh, or access with home assistant) devices that are in the 2.4 GHz network, not the ones in the same frequency. Vice-versa also happens. If two devices are in the same frequency, they cannot communicate with each other (for example I cannot access home assistant in my PI if it's connected in 5GHz if my laptop is also in that frequency, but as soon I change one to 2.4 GHz, i instantly can ping it).
To make it even more confusing, this is only an issue if both devices are connected to the same router. If they are in different decos, they can communicate irregardless of the frequency. In summary:
| Two devices can communicate? (both connected to the same deco) | 2.4GHz | 5Ghz |
|---|---|---|
| 2.4 GHz | Yes | No |
| 5GHz | No | Yes |
| Two devices can communicate? (devices in different decos) | 2.4GHz | 5Ghz |
|---|---|---|
| 2.4 GHz | Yes | Yes |
| 5GHz | Yes | Yes |
This issue is not making it possible for me to add all my devices to home assistant, since I can only communicate with my raspberry pi (or between any 2 devices, I've also tested with 2 laptops), since when I connect to the same deco, the devices need to be in different frequencies.
Some further information and a correction: the first table is backwards, devices can only communicate if they are in different frequencies, not the same.
I'll test with 2 devices (laptop and pi), changing their connection through the Deco app on my phone. I have also tested pings from either of these 2 devices to other local devices and the results are the same:
IP and Gateway information:
- Laptop (both for Office and Living Room - 5GHz):
- Laptop (both for Office and Living Room - 2.4 GHz):
- Raspberry Pi (Living Room - 5GHz):
- Raspberry Pi (Living Room - 2.4 GHz):
As you can see, there are no changes in IP Address of gateway on either device regardless of the deco connected or the frequency that they're connected to.
Ping tests:
- Raspberry PI will remain in the living room, I will only adapt its frequency. I have also tested with other local devices as well as my phone, result is the same.
Different Decos (Laptop in Office and Pi in Living Room):
- Laptop (5 GHz) -> pi (5 GHz) -> PASS
- Laptop (5 GHz) -> pi (2.4 GHz) -> PASS
- Laptop (2.4 GHz) -> pi (5 GHz) -> PASS
- Laptop (2.4 GHz) -> pi (2.4 GHz) -> PASS
For devices connected to different Deco units, there is no problem, all devices can communicate in the local network regardless of the frequencies.
Same Deco (Both in Living Room, both in office is the same result):
- Laptop (5 GHz) -> pi (5 GHz) -> FAIL (same happens with pi -> laptop)
- Laptop (5 GHz) -> pi (2.4 GHz) -> PASS
- Laptop (2.4 GHz) -> pi (5 GHz) -> PASS
- Laptop (2.4 GHz) -> pi (2.4GHz) -> FAIL (same happens with pi -> laptop)
Hope this can help, let me know if you need anything else.