Wifi Status summary

  • 1
  • Question
  • Updated 4 years ago
  • Answered
  • (Edited)


In our high school we use ap370 and 6.1r2a and have one accesspoint in each classroom.
You can see on the picture what is normal high collision and high Tx error.
We have tried with the system set to auto, and we have tried to make a manual plan (channel and power). Same result.
We have used  spectrum analyse, which gave us nothing. We know that we don't have microwave or alarm peers, this is tested previous.

Any Help
Jan Boje

Photo of Jan Boje

Jan Boje

  • 47 Posts
  • 0 Reply Likes

Posted 4 years ago

  • 1
Photo of Gary Smith

Gary Smith, Official Rep

  • 299 Posts
  • 61 Reply Likes
Hi Jan,

How many AP's do you have?
How close are they to eachother?
What power settings are you using?
How many SSID's on the AP's?

Could you post a couple of outputs please?

"show acsp"
"show acsp nei"
"show acsp channel-info detail | inc channel"

I'll let you know if anything stands out.

Kind Regards,
Gary Smith
Photo of Jan Boje

Jan Boje

  • 47 Posts
  • 0 Reply Likes

Hello Gary

We are using Aerohive in 4 schools, the smallest school have 900 students and the biggest school is about 1300 students.

We have just been using Aerohive for 6 month. so can you help with your the "show commands"

We hired a person to setup the radioprofile.

in a school we have about 1000 students they are using 1-2 divices each.

We have about 70-80 accesspoint in a school.

One accesspoint in every classroom distance between the accespoint ca 10m.

Power and channel is set to auto

3- 6  SSID

Jan Boje

Photo of Andrew MacTaggart

Andrew MacTaggart, Champ

  • 483 Posts
  • 86 Reply Likes
for the commands you would ssh into APs in question and run the cli commands at the #

http://www.aerohive.com/330000/docs/help/english/documentation/Aerohive_High-Density_Wi-Fi-Design-Co...

for the AP370 are you running 20MHz or 40MHz or 80MHz channel widths?

For such a deployment
I would set the channels and power manually
I would disable 2.4GHZ radios every other classroom and staggered for multi story structures.
I would disable lower data rates for b/g and a
I would use 3 SSID max
enable airtime fairness

to start with

the ACSP neighbor info can help you understand what the AP hears.

here is a video on the challenges of designing for K-12

https://vimeo.com/88435344










Photo of Gary Smith

Gary Smith, Official Rep

  • 299 Posts
  • 61 Reply Likes
Hi Jan,

As Andrew said, you can gather the outputs from the AP CLI and copy and paste to here.

"show acsp"
"show acsp nei"
"show acsp channel-info detail | inc channel"

Judging by the description you have given, I think both Andrew and Nick are thinking along the same lines as me and that some re-configuring could help.

Kind Regards,
Gary Smith 
Photo of Nick Lowe

Nick Lowe, Official Rep

  • 2491 Posts
  • 451 Reply Likes
Jan,

Who did your deployment?

Can I suggest you take a read of:

http://www.wlanpros.com/one-ap-per-classroom-approach-wrong/

Nick

Photo of Jan Boje

Jan Boje

  • 47 Posts
  • 0 Reply Likes
Hello
thanks for your input

I can say that airtime is set to fairness
lowest data rate is off
we have a consultant he should be high rate in Aerohive courses

I have made a ssh to a accesspoint as you can se below
KG44#show acsp

Interface Channel select state  Channel  Power ctrl state      Tx power(dbm)
--------- --------------------- -------- --------------------- -------------
Wifi0     Disable(User disable) 1        Disable(User disable) 14           
Wifi1     Disable(User disable) 36       Enable                14           
KG44#show acsp neighbor

wifi0(7) ACSP neighbor list:
Bssid               Mode     Ssid/Hive           Chan  Rssi(dBm)  Aerohive AP  CU CRC STA Channel-width
04fe:7f48:ad22 Access vuc 1 -84 no -- -- -- --
e01c:413b:b294      Access   kgwlan              1     -80         yes          20 0   3   20          
e01c:413b:b296      Access   KGTestVlan          1     -80         yes          19 0   3   20          
04fe:7f48:8101      Access   student-net         1     -87         no           -- --  --  --          
e01c:413c:cad6      Access   KGTestVlan          11    -80         yes          14 0   2   20          
04fe:7f48:ad21      Access   student-net         1     -84         no           -- --  --  --          
e01c:4136:7fd4      Access   kgwlan              1     -63         yes          25 0   2   20          
e01c:4136:7fd5      Access   kg-lektor           1     -63         yes          25 0   2   20          
e01c:4136:7fd6      Access   KGTestVlan          1     -63         yes          25 0   2   20          
e01c:413b:b455      Access   kg-lektor           1     -77         yes         
14 0   0   20          
e01c:413b:b454      Access   kgwlan              1     -77         yes          14 0   0   20          
e01c:413b:b456      Access   KGTestVlan          1     -77         yes          14 0   0   20          
e01c:413c:dfd4      Access   kgwlan              1     -84         yes          23 0   1   20          
04fe:7f48:ad23      Access   vuc-roskilde        1     -84         no           -- --  --  --          
04fe:7f48:ad25      Access   Laerer-net          1     -84         no           -- --  --  --          
e01c:413b:b8d4      Access   kgwlan              1     -80         yes          7  0   1   20          
e01c:413b:b8d6      Access   KGTestVlan          1     -80         yes          7  0   1   20          
e01c:413b:b556      Access   KGTestVlan          1     -79         yes          14 0   5   20          
e01c:413b:b555      Access   kg-lektor           1     -79         yes          14 0   5   20          
98fc:11b1:b0d7      Access   flleskrem         1     -88         no           -- --  --  --          
e01c:413a:c6d4      Access   kgwlan              1     -69         yes          25 0   1   20          
e01c:413a:c6d5      Access   kg-lektor           1     -69         yes          25 0   1   20          
e01c:413a:c6d6      Access   KGTestVlan          1     -69         yes          25 0   1   20          
e01c:4139:f415      Access   kg-lektor           1     -75         yes          17 0   0   20          
e01c:4139:f414      Access   kgwlan              1     -75         yes          17 0   0   20          
e01c:4139:f416      Access   KGTestVlan          1     -75         yes          17 0   0   20          
04fe:7f48:ad20      Access   vuc-koge            1     -84         no           -- --  --  --          
04fe:7f48:8104      Access   VUC-Print           1     -87         no           -- --  --  --          
04fe:7f48:ad24      Access   VUC-Print           1     -84         no           -- --  --  --          
04fe:7f48:8102      Access   vuc                 1     -87         no           -- --  --  --          
e01c:413b:b295      Access   kg-lektor           1     -80         yes          20 0   3   20          
e01c:413c:cad5      Access   kg-lektor           11    -81         yes          14 0   2   20          
e01c:413b:b8d5      Access   kg-lektor           1     -79         yes          7  0   1   20          
e01c:413b:78d5      Access   kg-lektor           1     -49         yes          15 0   1   20          
04fe:7f48:8103      Access   vuc-roskilde        1     -87         no           -- --  --  --          
04fe:7f48:8100      Access   vuc-koge            1     -87         no           -- --  --  --          
e01c:413c:ee16      Access   KGTestVlan          11    -56         yes          23 0   1   20          
e01c:413b:4516      Access   KGTestVlan          11    -78         yes          29 0   11  20          
e01c:413b:4514      Access   kgwlan              11    -78         yes          29 0   11  20          
e01c:413b:b554      Access   kgwlan              1     -79         yes          14 0   5   20          
e01c:413b:4515      Access   kg-lektor           11    -78         yes          18 0   9   20          
04fe:7f48:8105      Access   Laerer-net          1     -87         no           -- --  --  --          
e01c:413b:78d6      Access   KGTestVlan          1     -49         yes          15 0   1   20          
e01c:413b:78d4      Access   kgwlan              1     -50         yes          15 0   1   20          
e01c:413c:dfd6      Access   KGTestVlan          1     -84         yes          23 0   1   20          
e01c:413b:b3d4      Access   kgwlan              11    -61         yes          35 0   3   20          
e01c:413b:b3d5      Access   kg-lektor           11    -61         yes          34 0   4   20          
e01c:413b:b3d6      Access   KGTestVlan          11    -61         yes          25 0   1   20          
e01c:413b:9254      Access   kgwlan              1     -57         yes          27 0   2   20          
e01c:413b:9255      Access   kg-lektor           1     -57         yes          27 0   2   20          
e01c:413b:ccd4      Access   kgwlan              1     -60         yes          21 0   1   20          
e01c:413b:9256      Access   KGTestVlan          1     -57         yes          27 0   2   20          
e01c:413b:ccd5      Access   kg-lektor           1     -60         yes          21 0   1   20          
e01c:413b:ccd6      Access   KGTestVlan          1     -60         yes          21 0   1   20          
e01c:413c:dfd5      Access   kg-lektor           1     -83         yes          23 0   1   20          
e01c:4117:f6d4      Access   kgwlan              1     -84         yes          7  0   2   20          
e01c:4137:6c96      Access   KGTestVlan          6     -68         yes          1  0   1   20          
e01c:413b:6354      Access   kgwlan              6     -74         yes          17 0   3   20          
e01c:413b:6355      Access   kg-lektor           6     -74         yes          17 0   3   20          
e01c:413b:6356      Access   KGTestVlan          6     -75         yes          45 0   5   20          
e01c:413b:ced5      Access   kg-lektor           6     -67         yes          29 0   9   20          
e01c:413b:ced6      Access   KGTestVlan          6     -67         yes          48 0   7   20          
e01c:413c:c315      Access   kg-lektor           11    -51         yes          21 0   2   20          
e01c:413e:3d15      Access   kg-lektor           11    -65         yes          25 0   1   20          
e01c:413e:3d14      Access   kgwlan              11    -65         yes          28 0   1   20          
e01c:413e:3d16      Access   KGTestVlan          11    -65         yes          20 0   0   20          
e01c:4136:f596      Access   KGTestVlan          6     -51         yes          24 0   5   20          
e01c:413b:b715      Access   kg-lektor           6     -81         yes          28 0   11  20          
e01c:413d:8f96      Access   KGTestVlan          11    -71         yes          14 0   3   20          
e01c:413d:1695      Access   kg-lektor           6     -70         yes          23 0   3   20          
e01c:4136:f595      Access   kg-lektor           6     -51         yes          24 0   5   20          
e01c:413d:4295      Access   kg-lektor           6     -67         yes          24 0   2   20          
e01c:4137:6c95      Access   kg-lektor           6     -68         yes          50 0   6   20          
e01c:413d:1156      Access   KGTestVlan          11    -69         yes          21 0   4   20          
e01c:413c:c314      Access   kgwlan              11    -51         yes          21 0   2   20          
e01c:413c:c316      Access   KGTestVlan          11    -51         yes          21 0   2   20          
e01c:413d:1155      Access   kg-lektor           11    -69         yes          21 0   4   20          
e01c:413d:8f95      Access   kg-lektor           11    -71         yes          27 0   3   20          
e01c:413d:4296      Access   KGTestVlan          6     -67         yes          24 0   2   20          
e01c:413d:5394      Access   kgwlan              6     -85         yes          20 0   2   20          
e01c:413d:1696      Access   KGTestVlan          6     -70         yes          37 0   5   20          
e01c:413d:4294      Access   kgwlan              6     -67         yes          24 0   2   20          
e01c:4117:f6d5      Access   kg-lektor           1     -85         yes          7  0   2   20          
e01c:4117:f6d6      Access   KGTestVlan          1     -84         yes          11 0   2   20          
e01c:4136:f594      Access   kgwlan              6     -51         yes          24 0   5   20          
a2ea:9604:2fab      Access   Sandras iPhone      1     -77         no           -- --  --  --          
e2c9:7a42:46a1      Access   Cindys iPhone       1     -69         no           -- --  --  --          
6e3e:6d72:67af      Access   ffff                1     -83         no           -- --  --  --          
4018:b160:1015      Access   kg-lektor           1     -84         yes          15 0   7   20          
586d:8f57:4ad8      Access   HotSpotSystem-BUS_44111     -89         no           -- --  --  --          
00e0:0008:8bdd      Access   Panasonic Display1  1     -76         no           -- --  --  --          
e01c:413d:5396      Access   KGTestVlan          6     -83         yes          20 0   2   20          
7ed1:c33e:d629      Access   Stb iPhone          1     -86         no           -- --  --  --          
586d:8f57:3d58      Access   HotSpotSystem-BUS_44041     -87         no           -- --  --  --          
e01c:413c:e914      Access   kgwlan              1     -82         yes          6  0   2   20          
e01c:413c:e915      Access   kg-lektor           1     -82         yes          6  0   2   20          
d896:8547:b5c1      Access                       1     -87         no           -- --  --  --          
wifi1(8) ACSP neighbor list:
Bssid               Mode     Ssid/Hive           Chan  Rssi(dBm)  Aerohive AP  CU CRC STA Channel-width
e01c:413b:94e8      Access   kgwlan              40    -89         yes          13 0   2   20          
e01c:413d:1168      Access   kgwlan              36    -78         yes          7  0   2   20          
e01c:413d:1169      Access   kg-lektor           36    -79         yes          7  0   2   20          
e01c:413b:78e9      Access   kg-lektor           44    -59         yes          4  0   0   20          
e01c:413b:cee8      Access   kgwlan              40    -84         yes          17 0   9   20          
e01c:413b:cee9      Access   kg-lektor           40    -84         yes          15 0   10  20          
e01c:413b:78e8      Access   kgwlan              44    -59         yes          4  0   0   20          
e01c:413b:94e9      Access   kg-lektor           40    -87         yes          9  0   1   20          
e01c:413b:9268      Access   kgwlan              36    -71         yes          8  0   4   20          
e01c:413b:9269      Access   kg-lektor           36    -70         yes         
8  0   4   20          
e01c:413c:ee28      Access   kgwlan              48    -63         yes          13 0   0   20          
e01c:413c:ee29      Access   kg-lektor           48    -63         yes          13 0   0   20          
e01c:413b:b728      Access   kgwlan              36    -82         yes          11 0   1   20          
e01c:4137:6ca8      Access   kgwlan              40    -84         yes          3  0   3   20          
e01c:4137:6ca9      Access   kg-lektor           40    -85         yes          9  0   5   20          
e01c:413e:3d28      Access   kgwlan              48    -63         yes          9  0   0   20          
e01c:413a:c6e8      Access   kgwlan              36    -88         yes          6  0   2   20          
e01c:413d:42a8      Access   kgwlan              44    -75         yes          5  0   3   20          
e01c:413b:4528      Access   kgwlan              40    -82         yes          7  0   1   20          
e01c:413b:4529      Access   kg-lektor           40    -81         yes          7  0   1   20          
e01c:4136:7fe8      Access   kgwlan              48    -76         yes         
6  0   0   20          
e01c:413b:b3e8      Access   kgwlan              40    -71         yes          11 0   2   20          
e01c:413b:b729      Access   kg-lektor           36    -82         yes          11 0   1   20          
e01c:413b:b3e9      Access   kg-lektor           40    -71         yes          11 0   2   20          
e01c:413e:3d29      Access   kg-lektor           48    -63         yes          9  0   0   20          
e01c:413b:6368      Access   kgwlan              36    -87         yes          9  0   7   20          
e01c:413b:6369      Access   kg-lektor           36    -87         yes          9  0   7   20          
e01c:4136:7fe9      Access   kg-lektor           48    -75         yes          6  0   0   20          
e01c:413c:c328      Access   kgwlan              44    -65         yes          14 0   3   20          
e01c:413c:c329      Access   kg-lektor           44    -65         yes          14 0   3   20          
e01c:413d:42a9      Access   kg-lektor           44    -75         yes          5  0   3   20          
e01c:413a:c6e9      Access   kg-lektor           36    -88         yes         
6  0   2   20          
e01c:413d:8fa8      Access   kgwlan              40    -85         yes          17 0   1   20          
e01c:413d:8fa9      Access   kg-lektor           40    -87         yes          17 0   1   20          
e01c:4136:f5a8      Access   kgwlan              48    -57         yes          5  0   0   20          
e01c:4136:f5a9      Access   kg-lektor           48    -57         yes          5  0   0   20          
e01c:413b:cce8      Access   kgwlan              44    -73         yes          15 0   7   20          
e01c:413b:cce9      Access   kg-lektor           44    -73         yes          15 0   7   20          
04fe:7f48:ad2c      Access   vuc-roskilde        48    -87         no           -- --  --  --          
KG44#show acsp channel-info detail | inc channel

CU=channel utilization; TxU=Tx utilization; IU=interference utilization
This interface did not finish scanning all available channels.
This interface did not finish scanning all available channels.

 
Photo of Andrew MacTaggart

Andrew MacTaggart, Champ

  • 483 Posts
  • 86 Reply Likes
So your AP hears almost everybody.

a few things

depending on where you are in the world and your client population capabilities
you may benefit from using the DFS channels UNII2 and UNNI2e in the 5GHz band
I don't see any UNII3 channels being used

secondly no channel bonding in the 5GHz band is being used, this may be by design, you could get better performance from bonding, But before you leap into that you need to review you channel plan and your power levels

thirdly you will need to adjust the power levels on the 2.4GHz radio down and most likely disable some 2.4GHz radios completely

Basically it looks like you have a bad case of CCI or CCC
Photo of Nick Lowe

Nick Lowe, Official Rep

  • 2491 Posts
  • 451 Reply Likes
Being candid and upfront, if you have a deployment with an access point in every classroom and 6 SSIDs in some places, that has a strong 'smell' of things not having been done right.

(There is, for example, a tangible overhead from having that number of SSIDs deployed, particularly when the 802.11b data rates are left enabled. It is nearly always unnecessary to have that number due to the dynamic configuration that can be implemented for clients.)
Photo of Jan Boje

Jan Boje

  • 47 Posts
  • 0 Reply Likes
we just have 3 SSID KG..
the other SSID commes from another school, i can't do anything about that 
I don't understand where 802.11b comes from, in my radioprofile B should be disable and under the accespoint I can see "radiomode" g/n
Photo of Nick Lowe

Nick Lowe, Official Rep

  • 2491 Posts
  • 451 Reply Likes
When it comes to 802.11b issues with many SSIDs, we are concerned with what the lowest basic rate is.

What do you have set here:



Could you post a screenshot of what you have here?

(As you have a seemingly dense deployment of APs, do not copy this configuration. Your deployment might benefit with having either the 12 Mbps or 24 Mbps rate being set as the lowest basic rate with no lower rates than the chosen one then being offered, but this would have to be tested in your environment.)
Photo of Jan Boje

Jan Boje

  • 47 Posts
  • 0 Reply Likes
Photo of Nick Lowe

Nick Lowe, Official Rep

  • 2491 Posts
  • 451 Reply Likes
Jan,

As the data rates are sensible, it does look like this is going to be an issue caused solely by Co-Channel Interference/Contention.

The solution to this where it occurs, as Andrew says, will be a combination of:

1) Disabling radios or removing or moving APs where they are too densely deployed.
2) Manually lowering the TX power to something appropriate for the environment.

You would, I think, do well to consider seeking the services of a WLAN professional who can do this properly for you with the right tools and experience.

Nick
(Edited)
Photo of Jan Boje

Jan Boje

  • 47 Posts
  • 0 Reply Likes
thanks Nick and Andrew

On the 2.4GHz band I am at 14db for all accespoint now, I am sorry to say that it is a Pro. who have help us with the planning. how low can I go for TX 10 db ?
Andrew we have som radar problem in the area therefor we are just using the lower channel on 5GHz band.
I have been looking in to the link that you have sent, some of it I have read before they are good
I will be looking in to channel bonding in the 5GHz band, is there a video or a "how to" somewhere.?
and Andrew I am sorry but I am Danish what is CCI and CCC

Photo of Nick Lowe

Nick Lowe, Official Rep

  • 2491 Posts
  • 451 Reply Likes
I implicitly meant a different professional. As you have 1 access point per classroom, it is rather unlikely that there was much to any thought put in to the design process. It is likely that you simply have too many and will have to disable radios and move them about to get the best deployment. The internal antennas are fixed in the access points that you have so you cannot make any changes there.

CCI/CCC is Co-Channel Interference/Contention, you can Google search these terms.

Remember that it is not just the access points that you have to be mindful of, it is the clients too. You do not want to lower access point TX power too much as you will end up with too much of an imbalance between it and client TX power, this will normally give you high error rates and lots of retries.
(Edited)
Photo of Andrew MacTaggart

Andrew MacTaggart, Champ

  • 483 Posts
  • 86 Reply Likes

So you are danish - so we can assume you are in Denmark

DK

Denmark

ETSI

1 2 3 4 5 6 7 8 9 10 11 12 13

36 40 44 48 52 56 60 64 100 104 108 112 116 132 136 140

So it looks like U-NII3 is not allowed

and if you have issues with Radar blasts

then U-NII2 and 2e are out unless you are willing to have the channels change after radar is detected.

so for 5GHz that leaves you 4 channels @ 20MHz width

So channel bonding may not be an option

You have to know your client devices inside and out

for example:

the Intel® Centrino® Ultimate-N 6300

remember the Antennae will add gain 

for the 370

Antennas

  • 3x Integrated single band, 2.4-2.5 GHz Omni-directional antennas, 6.0 dBi peak gain
  • 3x Integrated single band, 5.1-5.8 GHz Omni-directional antennas, 6.0 dBi peak gain
So you check the EIRP value Equivalent isotropically radiated power is the highest RF signal strength that is transmitted from the antenna

some more info about EIRP

https://community.aerohive.com/aerohive/topics/how_does_this_eirp_cli_output_correlate

According to Andrew Garcia
"According to Matthew Gast's blog,
"MIMO works by using an antenna array that performs better than a single antenna. (The array gain is related to the number of antennas in the array; with two antennas, the array gain is 10 log (2) = 3.01 dB; with three antennas, the antenna array gain is 10 log (3) = 4.77 dB.)   - See more at: http://blogs.aerohive.com/blog/the-wi-fi-security-blog/did-the-fcc-really-limit-80211ac-beamforming#...""


There may be some video that are useful here

https://community.aerohive.com/aerohive/topics/aerohive_networks_wifi_101_videos

Cheers
A





(Edited)
Photo of Brian Powers

Brian Powers, Champ

  • 396 Posts
  • 92 Reply Likes
Your overall channel utilization isint that high, which is good.  And is likely because you have so many data rates disabled.  But you do have a ton of neighbors.

If you modify the radio profile for the 2.4 radio to lower the max transmit power down to say 14, but leave the individual APs set to "Auto" power and push that out, will the APs power themselves down to 8? 

The APs cannot go but 6 dB lower than the "Max Transmit Power" under the radio profile and Channel and Power (Optional Advanced Settings). 

If they lower themselves to 8, that means most likely they'd lower themselves further if possible because they are still hearing to many neighbors on their respective channel.  But as Nick said, lowering the power on the APs is not necessarily going to fix things, and could possibly cause other issues.


For pure kicks and troubleshooting, I'd wager if you turned off every other classrooms APs, you'd still have more than adequate coverage.  And possibly eliminate some of the issue that you may be running into. 


60 MHz and 80 MHz of frequency space have to be used and designed for very carefully. 
Photo of Jan Boje

Jan Boje

  • 47 Posts
  • 0 Reply Likes


Thanks to all I will do some reading and testing on your suggestion, any comment to my picture from my dashboard

my problem is that I have to balance coverage and Througput.
I can see when I got about 20-30 devices on one accespoint; I have a lot of retry  it is on the 2.4 GHz
as you can see on the picture
Photo of Nick Lowe

Nick Lowe, Official Rep

  • 2491 Posts
  • 451 Reply Likes
You are unlikely to be balancing those things at all through as you have one access point per classroom. You will, in the vast majority of cases, just get less throughput due to interference/contention under load while gaining no extra coverage within the classrooms.
(Edited)
Photo of Crowdie

Crowdie, Champ

  • 972 Posts
  • 272 Reply Likes
If your students are using iPads then a transmit power of 15 dBm seems to work the best with most wireless vendors.  This should have been allowed for in the initial site survey.

As you had the vision to deploy 802.11ac access points having one access point per classroom, unless the classrooms are very large, seems a little excessive.  I have deployed a number of schools and if I need one access point per classroom for client density I tend to use the AP121 2x2:2 802.11n access point as its signal doesn't propagate as far as the AP330 3x3:3 802.11n or AP370 802.11ac access points.

Therefore, I tend to agree with Nick and Andrew that you may have a wireless design issue here and you are, most likely, experiencing CCC issues as Nick suggested.