RT-AC88U Problem Communicating Between Wireless Clients

[astephon88]

I'm running Asuswrt-merlin 382.1_2 (though I've noticed the issue over pretty much all versions I've run). Even with Set AP Isolated disabled, I'm having issues with communications between wireless clients. I've even enabled and disabled Set AP Isolated in case there was some stale configuration stuck. From a wired client, I can always reliably ping all wireless clients, and vice versa. From 5GHz client to 5GHz client, it seems to reliably work. A 2.4GHz client to a 2.4GHz client almost always fails to ping. For 2.4GHz to 5 GHz/5 GHz to 2.4 GHz pairs, it sporadically will work, but typically does not. None of the clients have an issue getting out to the internet.

I first noticed it when I couldn't get the Harmony app to get a direct connection with my Harmony hub, and could only connect to it over the cloud. I had no issues with my RT-N66U running Merlin. Any ideas of what might be going on, or how I could debug this?

 

[Jack Yaz]

Have you disabled AirTime Fairness and MU-MIMO? Those are 2 of the usual troublemakers when turned on, so disable them and see if anything improves.

 

[astephon88]

Awesome! Thank you so much. Disabling AirTime Fairness on the 2.4GHz radio did the trick

 

[AC88U]

Can 100% confirm that it did the trick. Spend 2 weeks looking for solution

 

[mcko]

Hey there. Just to say, 3 years after, I encountered this bug (feature? ) in a rt-ac88u (not merlin) running latest firmware at this time. Really really boring. Forced to enable/disable AP isolation OR reboot.
This suggestion solved the problem : disabled airtime fairness on 2.4 GHz
I'll remember this one
Many thx.

 

[MrCarlsson]

Another 3 years later I ran into the same issue; solar panel inverter on 2.4 network where I couldn't reach the built-in web-ui to look at production etc.

Noticed I could ping the invertor from the router, but not from any devices on wired connection to the router (as my pc).
Found this thread after some searching, disabled Airtime Fairness and MU-MIMO, and Ta-Da! Ping response immediately and also access to the web-UI

Running AC88U on Merlin 386.12_4

 

[glens]

Just so you know, making those changes restarted the radio(s), and that merely restarting them in and of itself may be the reason things got fixed, not /necessarily/ that those are better choices.