Mobility Issue while disabling 2.4 GHz on SSID

[AbrarRazi]

Hello, 

We have Cisco EWC 9115AXI-D , While disabling the 2.4GHz on SSID, We are facing the mobility Issue. Clients are being connected with the farther AP instead on Nearest even client are not moving. also sometimes Clients are connecting with nearest one and automatically it jumping to the farther AP that create signal strength issue. 
EWC OS: 17.X.X

Could anyone let me know what is the problem?

I have set RF Global also the TX power is set Global. 

Regards

Abrar

[Flavio Miranda]

@AbrarRazi 

24Mbps as mandatory could cause problem. I would not put that.

[Mark Elsen]

  - Client roaming decisions are always autonomous ; make sure that the WiFi-driver is always up to date , you can also change the roaming sensitivity parameter on most adapters , 

 M,

[AbrarRazi]

Hi, 

It is not about one client It is about 500 Clients facing this issue, It is some misconfiguration from AP side or RF settings. Also i have set Typical_Client_Density_rf_5gh (5 GHz),  We have total 22 APs 9115AXI-D. 
Please suggest solution.

[Rich R]

> Please suggest solution.
Did you read my previous reply @AbrarRazi ?

And please confirm: what version of code are you running? (17.x.x is not an answer - we need to know the actual version)

[AbrarRazi]

IOS version 17.9.5

[Rich R]

So the first thing you should be doing is updating the code version as per the TAC recommended link below.
I suggest you read the rest of my original reply too.
Once your code is up to date run radioactive trace on affected clients to understand why they behave that way but as the others have highlighted client roaming is the client's choice ultimately.

[Leo Laohoo]

In other development, please keep the number of wireless client connected to a single 910x, 911x or 912x down to <15.  If the wireless client >25, the 910x, 911x or 912x will quickly run out of memory and the affected AP will crash.  

It would be a good idea to consider rebooting the APs daily.

Please refer to CSCvy08682. 

Oh, one important thing:  Cisco is NOT FIXING this bug.  

[Rich R]

We use 24Mbps mandatory and as long as the AP density is high enough to provide coverage it works fine.

But the lower data rates should be DISABLED (subject to sufficient coverage) - this is best practice:
https://www.cisco.com/c/en/us/td/docs/wireless/controller/ewc/17-3/config-guide/ewc_cg_17_3/m-best-practices.html
"We recommend that low data rates of 6 and 9 Mbps are disabled on 5GHz for better performance."

You do not mention what version of code you are using so first make sure it is up to date as per TAC recommended link below.
If you are using 17.12.x then you could also be affected by
https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwk12169 
or https://bst.cloudapps.cisco.com/bugsearch/bug/CSCwn27877

Does an AP reload fix the problem temporarily?
For those bugs above a shut/no shut of the 5GHz radio will also get it working again but you'll need to check it every day or just reload the AP on a daily basis.

Check your EWC config with the output of "show tech wireless" using the Config Analyzer (link below)

If the clients are Windows devices make sure WiFi drivers are fully up to date - for Intel:
https://www.intel.com/content/www/us/en/download/19351/intel-wireless-wi-fi-drivers-for-windows-10-and-windows-11.html

[Haydn Andrews]

I would consider disabling data rates below 12 Mbps
also look at the TPC settings 
suggest a wireless survey it could be neibouring APs heard at very good signal level, and its the client decision when to roam and which AP to join.

You ideally want cell edge at -65dBm with a 20% overlap with the neibouring APs