TPLink EAP225 option cell_density not working - sort of

Hi,
I got 2 TPLink EAP225 v3 with OpenWrt 22.03.2 installed as access points.

When I enable 5G and 2.4G simultaneously my clients that are further away, rather tend to connect to very low 5G (6 Mbit/s) than medium 2.4G (54 Mbit/s) which makes wifi nearly unusable.

So I figured that I should enable "option cell_density '3'" (Very High) on 5G to force clients with weak signal to use 2.4G instead.
For some reasons that does not seem to work as I am still seeing clients with 6 Mbit/s with 5G

I even took the trouble to set up a Linux laptop, put wifi in monitor mode and capture the beacon frames: Lowest speed announced: 24 Mbit/s

I don't understand why clients can still connect with 6 Mbit/s ?

What am I doing wrong?

cheers
Michael

you can't manage which wlan client will use.
What you could do is - activity polling, disassociate on low ack,...
so they switch to 2.4 if signal/ack drops.

Check also these options:
uci set wireless.radio0.ieee80211k='1'
uci set wireless.radio0.rrm_neighbor_report='1'
uci set wireless.radio0.rrm_beacon_report='1'
uci set wireless.radio0.ieee80211v='1'
uci set wireless.radio0.wnm_sleep_mode='0'
uci set wireless.radio0.bss_transition='1'
uci set wireless.radio0.time_advertisement='2'
uci set wireless.radio0.time_zone='CETXXXXXXXXXXX'

Hi zagi-tng

thanks a lot for your answer !

What exactly do you mean with "you can't manage which wlan client will use"
I am trying to use the same SSID but with 5GHz and 2.4GHz enabled

Of course I cannot force a client to use one or the other but in my understanding I could disable slow speeds with 5 GHz (like the 6 MBit/s) So instead of decreasing speed a client should disconnect from 5G (because there is no 6 Mbit speed available) and instead switch to 2.4G because there is e.g. 54Mbit/s available

Yes. "Coverage cell density" should do the trick, but it is still on client to decide which band to use.

Did you check ieee80211k and ieee80211v options mentioned in my post above ?
GIve "Distance Optimization" a try.

You could set radio0 (5G) to be more "aggressive" towards lost ack, polling timeout and such.