How to find 2.4 GHz-only clients

[Mark_Williams]

I have a Catalyst 9800 wireless network that is monitored by Catalyst Center. Broadcasting an SSID in 2.4 GHz and 5 GHz, and I'm trying to determine if it is safe to disable 2.4 GHz. I want to analyze the client sessions and determine if there are any clients that are 2.4 GHz-only. 

I could do this in Prime with AireOS by running the Client Sessions report, which would show each distinct client-AP session including information on what band the client connected to. In Catalyst Center, the Client Sessions report does not include the band.  

Is there a way I can get this info out of Catalyst Center or the Controller directly?

[Leo Laohoo]

"Turn off 2.4 Ghz and wait for the calls" is the best method.

LOGIC:  Just because a wireless client has joined 2.4 Ghz does not necessarily mean the wireless client can only support 2.4 Ghz.  There are many reasons why a dual- or triple band wireless NIC will join 2.4 Ghz.  And getting a list of wireless clients joined to 2.4 Ghz is not an ideal way to determine if the wireless client is a single-band (or not).

[Devaa]

From WLC CLI: 

show wireless client ap dot11 24ghz

From Catalyst Center: 

You can see which AP got how many 2.4 GHz clients from Catalyst Center as mentioned below. 

Assurance (Form Left top options) > Network Heatmap (Under AI Network Analytics)

• Show: Access points
• KPI: Client Count
• Time range: As per your need
• Location: Global or specific as per need
• Band: 2.4 GHz
• View by: Max

[Flavio Miranda]

@Mark_Williams 

Make the WLC do the job for you. Enable Band select on the WLC, make It aggressive. This way you dont need to disable SSID and after a few days you check How many clients still remains in 2.4ghz

[JPavonM]

The best method is the one from our colleague @Leo Laohoo to disable 2.4 and wait for any call.

Using vendor features like band select recommended by @Flavio Miranda  is not a method you can always trust in.

[Rich R]

sh wireless client summary
shows the client protocol
sh wireless client summary detail
gives the same with a bit more detail.