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Occasional Contributor II
Posts: 66
Registered: ‎08-09-2012

Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

[ Edited ]

I'm having an issue with low goodput numbers at an office locatioin. The office is setup with two 3400 Series Mobility Controllers with several Aruba AP225 connected. Both the controllers and APs are connected to dedicated switches and isolated from wired users.

 

Controllers are running OS version 6.4.1.0 and average 250 to 450 clients daily.

 

Most of the clients are connected at 5Ghz band with ac Radio/Client PHY 80 Mhz and Radio 80 Mhz/ Client 40Mhz.

 

I've noticed that several client workstations show very low Goodput numbers. I believe the issue is related to a driver issue with the workstation. But, I want to confirm that a config on the controller isn't causing the issue.

 

I have several other controllers in the field with the same configs. None of the others appear to be experiencing the same low goodput from client workstations.

 

Any suggestions/advice for possible root causes for issue? mobility controller configuration? workstation Wireless NIC driver?

Anthony
Community Administrator
Posts: 2,254
Registered: ‎12-03-2013

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

[ Edited ]

Have you made a correlation with AP location and the location of the clients? Could they at the edge of the cell?

 

Low Goodput = < 24 Mb data rate 

 

 

 

CWNA, ACMP, Security +
Occasional Contributor II
Posts: 66
Registered: ‎08-09-2012

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

Thanks for the response. The only factor that seems to be contributing to the low goodput is the frame types..specifically the conversion process.

 

The 3400 controller w/ AP225s is not converting bcast and mcast frame types into unicast correctly. I have 4 other controllers installed in different offices. The same workstations are used at all 4 offices. None of the other sites are experiencing the same issue.

 

I checked and verified: Convert Broadcast ARP request to unicast is enabled. Drop Broadcast and Unknown Multicast is not selected on each controller.  

 

 

Anthony
Guru Elite
Posts: 20,773
Registered: ‎03-29-2007

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

anthony.i.brice,

 

That "low goodput" number could be due to contention (the presence of other devices).  Both of those screenshots show less than 2% of the traffic to the client is dropped, which is typically very good.



Colin Joseph
Aruba Customer Engineering

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Occasional Contributor II
Posts: 66
Registered: ‎08-09-2012

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

I agree. The less than 2% is a good number. Our environment exists of two main wireless NIC: Broadcom 11a and Intel Dual Band AC 7260.

 

However, if you look at the Channel Busy % , the site with AP225 posts Channel Busy % above 50% consistently, which triggers massive fluatuations in speed. Basically, the speed drops from 866Mbps to 720Mbps to 124Mbps to 24Mbps in less than 2 minutes. No movement in laptop position. Client SNR is 45db. Laptop is connected to the same AP..no roaming. 

 

In contrast, the site with AP135s post Channel Busy %'s below 20%. The speed of the same client machine remains 300Mbps. No fluatations in speed with the addition of more applications or Lync usage.

Anthony
Guru Elite
Posts: 20,773
Registered: ‎03-29-2007

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

You could try using 40 or even 20 MHz channels in those locations to improve that. It requires almost ideal conditions and short distance to maintain 866 or even 720. It is not as hard to achieve 300, so the speed might be a little misleading.

Is channel busy across all channels in the 5ghz?


Colin Joseph
Aruba Customer Engineering

Looking for an Answer? Search the Community Knowledge Base Here: Community Knowledge Base

Occasional Contributor II
Posts: 66
Registered: ‎08-09-2012

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

The Channel Busy appears to be evenly distributed across the 80Mhz Channels 149, 161, 153,157.

 

I noticed that the AP Regulatory Domain default profile did not have a channel group selected. It was listed as N/A. 

 

So, I set the Valid 802.11a 80Mhz Channel Group to 149-161.

Anthony
Guru Elite
Posts: 20,773
Registered: ‎03-29-2007

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

You should revert (change back) your settings in the regulatory domain profile, because those do not control the width of your channels directly.

 

To change from 80 mhz to 40 mhz, you should change the under the 5ghz radio, you should change the ARM profile.  Uncheck 80 mhz support and leave "allowed bands" as a-only:

arm-40-mhz.png

 

 

To change to 20 mhz channels, in your ARM profile under the 5ghz radio, Uncheck 80 mhz support and make "Allowed Bands" None:

 

arm-20-mhz.png



Colin Joseph
Aruba Customer Engineering

Looking for an Answer? Search the Community Knowledge Base Here: Community Knowledge Base

Occasional Contributor II
Posts: 66
Registered: ‎08-09-2012

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

Thanks for the suggestions. I'll revert the regulatory domain profile back to the default.

 

I already have Allowed Bands for 40Mhz Channels set to "A-only". However, I see that 80Mhz Support was enabled. I'll deselect the 80Mhz Support option in the ARM Profile.

 

Thanks for the suggestion. I'll give that a try.

Anthony
Occasional Contributor II
Posts: 66
Registered: ‎08-09-2012

Re: Issue w/ Low Goodput Numbers on 3400 Series Controller/AP225s

Finished with the config changes. I did see a decrease in the Channel Busy % on 5Ghz Band. So far, the speeds seems to have settle down and remain consistent on both 11n and 11ac client test workstations.

 

Also, I've seen a much improved Goodput numbers. Much more frame types are falling into Ucast then before.

 

However, I did notice that the max speed of the 11ac client has changed from 866Mbps to 400Mbps, which is probably a result of disabling 80Mhz Support on the RF Profile. What are your suggestions on how to maintain the availability and benefits of 80Mhz and allow the 11ac clients the capability of leveraging the higher speeds?

Anthony
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