Wireless Access

Hello,

 

People in this area where the AP at are complaining for poor performance and sometimes drop out. Then I checked the dashboard and I saw this Poor quality. I don't know what it means but it is probably the same reason the clients are experiencing.

 

How can I fix this?

 

Thanks.

Click on the Help in the upper right hand corner, then click on any heading that you want explained.

 

You have high utilization on an access point and there are few clients, so automatically it lists it as "poor".  If you can get on the commandline, I would call up the "show ap arm state ap-name 058-110b-ap-w1" and see how many access points it can see.  It is quite possible that you have too much coverage.

Hi Joseph,

 

Here's the command output.

(cpp-001-aruba-wc1) #show ap arm state ap-name 058-110b-ap-w1

AP:058-110b-ap-w1 MAC:18:64:72:x Channel:149 EIRP:22 Max EIRP:22 Edge:enable
Client Density:0 Valid neighbors: 17 Relevant neighbors: 2 Rx Probe Reports: 9348
Moves(T/S):2/1 Sticky(T/S):2/1 Bandsteer(T/S):0/0 Loadbal(T/S):0/0
Neighbor Data
-------------
Name               	 IP Address     SNR (dB)  Path Loss (dB)  Channel/Pwr  Neighbor Density  Neighbors (R/T)  Relevant
----               	 ----------     --------  --------------  -----------  ----------------  ---------------  --------
058-208b-ap-w1      	 10.111.21.185  10        105             36/21        0                  1/26             
058-310b-ap-w1     	 10.111.21.253  23        91              157/21       0                  3/23             
058-105b-ap-w1     	 10.111.21.154  8         102             157/15       0                  8/18             
058-206b-ap-w1     	 10.111.20.201  9         107             153/21       0                  9/18             
058-201b-ap-w1     	 10.111.21.192  6         108             44/21        0                  2/19             
058-106b-ap-w1      	 10.111.21.130  15        105             40/21        0                  3/21             
00:24:6c:ac:x   	 -              -         -               -            -                 -                -
058-102b-ap-w1     	 10.111.21.149  6         110             157/21       0                  2/17             
058-ap-lobby-w1     	 10.111.21.98   6         110             161/21       0                  1/22             
00:24:6c:ac:x 	 -              -         -               -            -                 -                -
00:24:6c:ac:x  	 -              -         -               -            -                 -                -
00:24:6c:ac:x 	 -              -         -               -            -                 -                -
059-108-01a-ap1-w1  	 10.111.20.138  7         105             48/18        0                  0/5              
00:24:6c:ac:x  	 -              -         -               -            -                 -                -
00:24:6c:ac:x 	 -              -         -               -            -                 -                -
058-116b-ap-w1     	 10.111.20.173  8         109             36/21        0                  2/11             
00:24:6c:ac:x   	 -              -         -               -            -                 -                -
058-313b-ap-w1           10.111.20.175  10        0               11/12        0                  9/19            Yes
057-102b-ap-w1           10.111.20.57   9         101             11/12        0                  9/25             
058-310b-ap-w1           10.111.21.253  33        75              11/12        0                  9/41            Yes
00:24:6c:e6:x        -              -         -               -            -                 -                -
058-106b-ap-w1           10.111.21.130  13        94              1/12         0                  13/24            
058-206b-ap-w1           10.111.20.201  20        95              11/12        0                  12/21            
058-208b-ap-w1           10.111.21.185  20        89              1/15         0                  12/32           Yes
00:24:6c:ac:x        -              -         -               -            -                 -                -
058-305b-ap-w1           10.111.20.185  6         0               11/12        0                  11/20           Yes
057-331b-ap-w1           10.111.20.14   9         99              11/15        0                  10/26            
058-105b-ap-w1           10.111.21.154  10        102             6/12         0                  7/23             
058-205b-ap-w1           10.111.21.2    8         101             11/12        0                  14/26            
00:24:6c:ac:x        -              -         -               -            -                 -                -
00:24:6c:a8:x        -              -         -               -            -                 -                -
058-113b-ap-w1           10.111.21.158  25        0               6/21         0                  3/14            Yes
057-110b-ap-w1           10.111.20.56   6         100             1/15         0                  5/19             
00:24:6c:ac:x        -              -         -               -            -                 -                -
058-130b-ap-w1           10.111.20.49   11        0               6/18         0                  9/27            Yes
058-306b-ap-w1           10.111.21.197  51        0               6/12         0                  8/28            Yes
057-310b-ap-w1           10.111.21.212  9         0               6/18         0                  6/18            Yes
00:24:6c:ac:x        -              -         -               -            -                 -                -
057-ap-lobby-w1          10.111.20.59   3         114             1/18         0                  10/26            
00:24:6c:ac:x        -              -         -               -            -                 -                -
00:24:6c:a8:x        -              -         -               -            -                 -                -
00:24:6c:ac:x        -              -         -               -            -                 -                -
00:24:6c:a9:x        -              -         -               -            -                 -                -
057-205b-ap-w1           10.111.21.254  5         102             11/12        0                  12/30            
111-pool-deck-ap06-w1    10.111.15.8    4         117             11/24        0                  3/14             
058-201b-ap-w1           10.111.21.192  4         105             11/12        0                  10/34            
058-ap-lobby-w1          10.111.21.98   3         100             11/12        0                  11/32            
00:24:6c:ac:x        -              -         -               -            -                 -                -
057-106b-ap-w1           10.111.20.54   4         0               11/12        0                  8/23            Yes
00:24:6c:ac:x        -              -         -               -            -                 -                -
059-108-01a-ap1-w1       10.111.20.138  14        0               6/20.5       0                  2/11            Yes
111-north-patio-ap04-w1  10.111.14.43   26        102             1/12         0                  11/26            
057-136b-ap-w1           10.111.21.92   6         104             11/12        0                  7/28             
058-136b-ap-w1           10.111.21.101  2         104             11/12        0                  15/33            
Legend: R = Relevant, T = Total,  Neighbor Density = (Overlap/Neighbor's Density/ Overlap to local density ratio/ Overlap to neighbor's density ratio)


(cpp-001-aruba-wc1) # 

 

From the perspective of that access point, it seems like you have very good coverage. I would consider turning down the power by making your max TX power on the g band 12 and the max TX power on the a band to 15. That would require you creating separate radio and arm profiles for each band. First, run that command against any access point where you think you do not have good coverage to see how many other access points can be seen

Hi,

 

Yes, I did made those Tx adjustment you suggested to that particular AP. Do you also want me to apply this to other AP? From the list earlier, how will I know which AP needs to be adjusted?

 

Thanks.

The high utilization is coming from the access points around that access point. You could apply those settings to that entire ap-group, and then look at the channel utilization after you do that.

I think I will observe first before adjusting the entire AP group. It looks it is getting better since lowering maxTx to 12 and minTx to 3 for 2.4ghz and maxTx to 15 and minTx to 3. I hope it stays this way.

 

Thanks.

 

 

 

Edit:

 

Nevermind, I checked other AP's in that building and most  seem to have high channel utilization so  I lowered all Tx.  Anyway, are there any more setting I should do in the ARM profile. There are many settings but I don't  if they can help make things better.

Yes, you would have to lower all access points, because utilization is something shared across all access points.

You can enable "Quality Aware Arm" which would factor in channel utilization when access points choose channels. This is of course very limited in the 2.4ghz spectrum.

I would look at all my access points to see if things have lowered before doing the quality aware change. There are quite a few environments that have higher utilization but they work, so you need to baseline your utilization and user experience to determine what is the functional utilization for your network.

If your users are having problems, we can consider something else...

I just enabled Channel Quality Aware Arm.

 

How about Rogue AP Aware? should I leave it unchecked? 

No, because it will not help your high utilization issue. That setting is rarely enabled in practice. The main setting in the ARM profile that is manipulated is the max and min transmit power like we did before. The other settings are not changed often.

Update:

 

It is back to high channel utilization and porr quality again.

High utilization can result from a speed test or someone downloading a lot of data at the time. Sustained high channel utilization should be of concern. If you have Airwave, you can observe historically what your utilization is and if it remains high with no users on that access point, for example.

Have you observed that all your access points lowered their power?

It doesn't look like the MaxEIRP changed at all. Still 21. Am  looking at the right numbers?

 

You need to look at the current EIRP, not the MAX. The max is the regulatory domain max. How many access points do you have? How many ssids? Do you have drop broadcast enabled on your virtual ap profile for all your ssids?

I have over 1400+ AP's using two 7240 controllers. So far, the problem is in building 58 (ap grpup cpp-apg-058). I think we installed too many AP's for that building.

I just downloaded your screenshot two posts ago and it looks like you are doing 80mhz channels on the 5ghz. There are not enough 80 mhz channels in a high density environment to do 80 MHz channels. In the ARM profile, you should uncheck 80 mhz channels. Depending on how dense you are, you should go to 20 MHz channels by setting 40 MHz allowed to "none" in the arm profile.

Based on density requirements, 2.4 GHz band will always have higher utilization because there are only 3 channels available. There are things that you could do, like "remove" the lower rates, in the SSID profile, but you should make the other changes I suggested in the ARM profile before doing that...

The building is a dorm and the density is not a concern. 1 AP would probably not exceed 15-20 clients.

 

Anyway, I still did your  your instruction to uncheck 80mhz and not allow 40mhz.

 

 

Are the access points mounted in the halls or in the rooms?

I just took over the wireless in a little over 2 months and I haven't been in that particular building and the ones I've seen is that they are in the hallway so I bet BLDG 58  AP's are in the hallway too. I know it is a mistake but that's how they did it.

Well, that could explain the High utilization. It is suboptimal, but it can work if we keep making adjustments based on user temperature.

Yeah, and they installed too many and too close to one another. I just turned one to air monitor and I hope that helps.

 

Thanks anyway, I'll update if things gets better. 

UPDATE:

 

The AP's arent actually in the hallways but in their own room. The walls are made of ~5 inch concrete and not a dry wall.

 

I went there and did some test. I noticed that my devices don't nescessarily connect to the closest AP. I have to turn my device WiFi on and off to connect to the closest AP.

 

I also did some spectrum analysis if that helps because I wanted to observe the effect of the microwave oven and mobile hotspot.

 

Note: at ~10:03:10 I started the microwave and turned off at 10:04:40

Wifi-CPP,

 

How many access points are in that room?  Clients do not necessarily connect to the nearest AP, because the signal might not be sufficiently different.

1 access point. Not all rooms has AP. More like 1 AP every other room but not perfectly arranged that way.