Optimization of CBW240AC

[Zbaardsen]

I get disconnected and reconnected to my AP's a lot kicking me off the 5GHz network and pushed to the 2.4GHz network. The SSID is the same but split frequency. There is only about 1% interference on the 5GHz network and the 2.4 averages about 20%. I have gone through settings multiple times trying to tweak them, but unable to get good results usually. Is there somewhere I can find a good explenation of settings or someone that knows the in and outs of them that can help me optimize the settings? I have looked up articles trying different ideas but none have helped. Thank you.

I will try to answer any questions as best as I can as I am busy most days.

[marce1000]

          - Check the logs on the AP(s) when that happens , 

 M.

[mcomadmin]

I have a similar issue with iPhones specifically, using 240ACs on firmware version 10.9.1.0.

I just bought these and upgraded them immediately. Will try rolling back to an older version.  

*spamApTask0: Jul 25 17:50:56.660: %APF-4-MOBILESTATION_NOT_FOUND: apf_api.c:57524 Could not find the mobile d6:c3:06:f1:32:7a in internal database
*apfReceiveTask: Jul 25 17:50:56.568: %APF-5-CLIENT_DEAUTHENTICATE: apf_80211.c:4056 Client Deauthenticated: Client MAC: d6:c3:06:f1:32:7a, Ip Address: (0.0.0.0), AP Name: AP01, Radio: 5 GHz , WLAN Id: 1, Reason: 108.
*apfReceiveTask: Jul 25 17:50:56.567: %APF-5-CLIENT_DISASSOCIATE: apf_80211.c:4325 Client Disassociated: Client MAC: d6:c3:06:f1:32:7a, Ip Address: (0.0.0.0), AP Name: AP01, Radio: 5 GHz , WLAN Id: 1, Reason: 1.
*apfMsConnTask_0: Jul 25 17:48:37.715: %APF-5-CLIENT_ASSOCIATE: apf_80211.c:13338 Client Association: Client MAC: d6:c3:06:f1:32:7a, AP Name: AP01, Radio: 5 GHz , WLAN Id: 1.
*apfReceiveTask: Jul 25 17:47:30.646: %APF-5-CLIENT_DEAUTHENTICATE: apf_80211.c:4056 Client Deauthenticated: Client MAC: d6:c3:06:f1:32:7a, Ip Address: (10.0.5.21), AP Name: AP01, Radio: 5 GHz , WLAN Id: 1, Reason: 4.
*apfReceiveTask: Jul 25 17:47:30.645: %APF-5-CLIENT_DISASSOCIATE: apf_80211.c:4325 Client Disassociated: Client MAC: d6:c3:06:f1:32:7a, Ip Address: (10.0.5.21), AP Name: AP01, Radio: 5 GHz , WLAN Id: 1, Reason: 4.
*apfReceiveTask: Jul 25 17:37:46.153: %APF-5-CLIENT_RUN_STATE: apf_foreignap.c:2245 Client Associated: Assigning Ip Address: (10.0.5.21) to Client MAC: d6:c3:06:f1:32:7a.
*apfMsConnTask_0: Jul 25 17:37:43.878: %APF-5-CLIENT_ASSOCIATE: apf_80211.c:13338 Client Association: Client MAC: d6:c3:06:f1:32:7a, AP Name: AP01, Radio: 5 GHz , WLAN Id: 1.
*apfReceiveTask: Jul 25 17:35:14.439: %APF-5-CLIENT_DEAUTHENTICATE: apf_80211.c:4056 Client Deauthenticated: Client MAC: d6:c3:06:f1:32:7a, Ip Address: (10.0.5.21), AP Name: AP01, Radio: 5 GHz , WLAN Id: 1, Reason: 4.
*apfReceiveTask: Jul 25 17:35:14.438: %APF-5-CLIENT_DISASSOCIATE: apf_80211.c:4325 Client Disassociated: Client MAC: d6:c3:06:f1:32:7a, Ip Address: (10.0.5.21), AP Name: AP01, Radio: 5 GHz , WLAN Id: 1, Reason: 4.
*apfMsConnTask_0: Jul 25 17:25:30.231: %APF-5-CLIENT_ASSOCIATE: apf_80211.c:13338 Client Association: Client MAC: d6:c3:06:f1:32:7a, AP Name: AP01, Radio: 5 GHz , WLAN Id: 1. 

[Rich R]

1. First thing to understand: the choice of 2.4 or 5 GHz is always a client decision.
2. Simplistically 2.4 often looks more attractive to clients because the signal strength is often higher because of better coverage and penetration.

So what can you do about it:
1. Your easiest option by far, if you can, is to use separate 2.4GHz and 5GHZ SSIDs - no more problem.
2. Enable "Client Band Select" - the AP tries to nudge the client to 5GHz but cannot force it.
3. Reduce the Tx power level on the 2.4 GHz radio to make it appear less attractive to clients which only looks at signal strength.
4. On the clients which support it - like Intel drivers on Windows - set "Prefer 5GHz band" in the driver "Preferred Band" settings.

[mcomadmin]

I have resolved my issues by enabling 802.11r https://www.cisco.com/c/en/us/support/docs/smb/wireless/CB-Wireless-Mesh/kmgmt-2856-mobile-phone-cbw-enable-802.html 

Also, double check your DHCP lease time. While testing various scenarios including setting a very short lease time (I’m deploying a public/guest hotspot), I observed that the iPhone, while locked/idle doesn’t seem to “wake up” to renew its lease.