Wireless Access

Hello,

 

I have some stationary computers that are losing their connection to the AP.   It has the latest firmware on it.

If your clients are running Intel 7260 cards, you might take a look at this thread.  It has quite a bit of information about the issues that peopel are seeing with those specific cards.  

 

If it's not that, adding a bit more detail might help diagnose the issue.  What AP's?  What clients?

Hello,

 

I'm going onsite tomorrow to see if I can gather any info.  They are all AP225s.   The workstations are 90% macbooks pro and air.   My guess is no station is more than two years old.  I don't know if the macbooks have any intel nics in them as I usually support PCs.

boe,

 

Recent macbook pros have Broadcom NICs in them, NOT Intel nics.  If you are having problems, you should open up a TAC case in parallel, so that they can give you ideas about what needs to be done prior to your visit.

boe,

 

If you  can ssh into the controller, please post the output of "show ap radio-summary"

Thanks I just Puttied in and that is not an option on my units - there is Show ap, ap-alert, ap-env, app-services, aps.

 

I can do show radio  (not sure if that is close enough)

 

94:b4:0f:c8:87:fc  IAP6# show radio

2.4 GHz:
Legacy Mode:disable
Single Chain Legacy:disable
Beacon Interval:100
802.11d/802.11h:disable
Interference Immunity Level:2
Channel Switch Announcement Count:0
MAX Distance:600
Channel Reuse Type:disable
Channel Reuse Threshold:0
Background Spectrum Monitor:disable
Max Tx Power:0
Min Tx Power:0
5.0 GHz:
Legacy Mode:disable
Single Chain Legacy:disable
Beacon Interval:100
802.11d/802.11h:disable
Interference Immunity Level:2
Channel Switch Announcement Count:0
MAX Distance:600
Channel Reuse Type:disable
Channel Reuse Threshold:0
Background Spectrum Monitor:disable
Standalone Spectrum Band:5ghz-upper
Max Tx Power:0
Min Tx Power:0

 

I do notice the TX power - I think mine are set for 12 to max not sure what this is saying.

try "show ap arm history"

Interface :wifi0
ARM History
-----------
Time of Change       Old Channel  New Channel  Old Power  New Power  Reason
--------------       -----------  -----------  ---------  ---------  ------
2015-10-30 13:55:57  36+          132+         24         24         Q
2015-10-30 13:53:48  100+         36+          24         24         M
2015-10-30 13:47:24  108+         100+         24         24         I
2015-10-30 11:22:51  60+          108+         24         24         I
2015-10-30 11:18:36  36+          60+          24         24         Q
2015-10-30 11:16:33  132+         36+          24         24         I
2015-10-30 10:57:27  36+          132+         24         24         Q
2015-10-30 10:55:20  140+         36+          24         24         M
2015-10-30 06:49:17  36+          140+         24         24         Q
2015-10-30 06:47:10  100+         36+          24         24         M
2015-10-30 06:39:39  140+         100+         24         24         I
2015-10-30 02:59:53  149+         140+         24         24         I
2015-10-30 02:51:59  157+         149+         24         24         M
2015-10-30 01:31:04  157+         157+         Max        24         P-
Interface :wifi1
ARM History
-----------
Time of Change       Old Channel  New Channel  Old Power  New Power  Reason
--------------       -----------  -----------  ---------  ---------  ------
2015-10-30 01:33:36  6            6            15         12         P-
2015-10-30 01:32:37  6            6            18         15         P-
2015-10-30 01:31:57  6            6            21         18         P-
2015-10-30 01:31:46  6            6            24         21         P-
2015-10-30 01:31:05  6            6            Max        24         P-
I: Interference, R: Radar detection, N: Noise exceeded, Q: Bad Channel Quality E: Error threshold exceeded, INV: Invalid Channel, G: Rogue AP Containment, M: Empty Channel, P+: Increase Power, P-: Decrease Power, 40INT: 40MHZ intol detected on 2.4G, NO40INT: 40MHz intol cleared on 2.4G, OFF: Turn off Radio, ON: Turn on Radio

It seems like your ARM power is too high.  You need to go into ARM and set the Minimum and max to 9 and 15 respectively.  Click on RF> Advanced and then change the parameters like in the highlighted portion of this screenshot:

Thanks - I had tried that a few days ago but it didn't seem to help so I put it back.  I'll set it back again.

If you look at the ARM history you'll see that a lot of channel-switches are occuring (by ARM), those can be disruptive.

 

Questions:

 

- Are there muching AP's on the same channel active?

- What is the noise-floor the AP's are reporting?

 

If you have lots AP's on the same channel (at least for 5GHz), you could consider moving to 20MHz channels (instead of 40MHz as it seems to be know).

Hello,

 

Where do I check the noise floor?

 

We have a dozen APs so yes they are all on 1, 6 or 11.   There isn't a lot of switching between channels but there is some.

Can you let me know where to go to change from 20 to 40hz?

---

@boe wrote:

Hello,

 

Where do I check the noise floor?

 

We have a dozen APs so yes they are all on 1, 6 or 11.   There isn't a lot of switching between channels but there is some.

Can you let me know where to go to change from 20 to 40hz?

---

The noise should be a column on the AP display in the GUI.

 

You can change from 40 to 20 by going to RF> Advanced and Change "Wide Channel Bands" to "None".  Did you change the "Min Transmit Power" on that page to 9?

 

Thanks,

 

In the RF Dashboard section I see

All access points - utilization, noise and errors with only 1 green bar at the bottom of each.

 

In RF advanced, ARM, I see

Band steering mode - prefer 5GHz

Airtime fairness - fair access

Client match - enabled

CM Calculating interval 3 sec

CM neighboring match 75%

CM threshold 5

SLB mode Channel,

min transmit 3

Max 21

Client Aware disabled

Scanning Enabled

Wide Channel bands and my choices are 5GHz, none, all, 2.4GHz

I have 80MHz support and my choices are disabled, enabled

 

RADIO

2.4GHz band

legacy only diabled

802.11d/802.11h disabled

beacon interval 100ms

Interference immunity level 2

Channel switch announcement 0

Background spectrum monitoring disabled

Custom Arm power range (unchecked)

 

5GHz band

legacy only disabled

802.11d/802.11h disabled

beacon interval 100ms

Interference immunity level 2

Channel switch announcement 0

Background spectrum monitoring disabled

Custom Arm power range (unchecked)

Why is max transmit as high as 21?  That causes roaming issues an disconnects..

 

On the SSID portion of that SSID, do you have "Broadcast Filter ARP" enabled?

 

 

Someone recommended I set a max earlier to help with the disconnects.  I'm happy to try anything to stop the clients from having issues.

 

Currently ARP broadcast filtering is set for disabled - would you suggest enabling it?

 

Currently I have

Broadcast filtering disabled

DTIM interval 1 beacon

Multicast transmission optimization disabled

Dynamic multicast optimization disabled

DMO Channel utilization threshold 90%

 

Transmit Rates

2.4GHz min 12, max 54

5GHz min 12, max 54

They recommended a max of 15 or 18. Power is logarothmic, so the power at 18 is half that of 21. 15 is a quarter of that.

I tried setting it to 18 and the clients complained they had even more issues.

I would open a tac case in parallel, because it seems we are not getting the full picture.

Thanks - I've opened a case... Trying to get any info at all from the client e.g. computer name, when they drop, are they stationary or moving...

 

In the mean time would you suggest turning on arp filtering?

Broadcast filter ARP both suppresses broadcasts and does proxy ARP.  Unwanted Broadcasts decrease performance considerably, especially if you have wired and wireless clients in the same VLAN.

Good to know.

 

The Wired and Wireless are on seperate vlans.