Hi, I have sent this to TAC and the response was unable to pin point the issue and difficult to analyze it and asked me to run iPerf which I think it has nothing to do with this issue. I have given them the whole details though!
So I post it here and appreciate you guys can take a look and possibly assist with it:
Env: C9800 17.9.5 - AP 9164I
I have an AP showing High Utilization sometimes and that causes wireless client to experience very low RSSI and performance even though the client is not more than 10 feet away and not many clients. I have tshoot this and I need your help for further tshoot. here is what I have done - there are neighboring APs and the channels are different and far in my understanding: Nearby APs :
AP a00XXXXX slot 1 : -70 dBm on (116, 40 MHz)
AP a00f.3xxxxx slot 1 : -84 dBm on (136, 40 MHz)
AP 345dxxxxxf slot 1 : -85 dBm on (100, 40 MHz)
AP a00f.xXXXXX slot 1 : -90 dBm on (116, 40 MHz) -
diged into DNAC analytics and realized the time user experiences wireless drop and bad performance DNAC reported high channel utilization on AP and poor RSSI on wireless client ( see attached)
- DNAC shows poor RSSI ~40% of time for the client even though the AP is close
- Then I checked AP DNAC analytics and WLC logs and noticed whenever the user experiences bad network the AP shows high utilization 70-80% which made me think it should be the root cause of the issue
- The high CU could be for many reason and mainly interference, but the user is connecting on 5Ghz channel and I could not find a significant interference on that radio nor channel overlap.
- So then realized the Hi CU is reporting for Tx rate and on that refers to Tx management frames is occupying high BW
As of the moment I think its high channel utilization causing this issue and according to DNAC it is mainly TX management data. but these are all my analysis and finding, not sure about the next step?!
