Wireless Access

Every once in a while I will see the noise floor on an AP (5GHz radio, 20MHz channels) increase from -95 to -75 and stay there for about 10 minutes.  Client SNR drops to an unacceptable level, resulting in poor call quality for the duration of the high noise.  I've poured through airwave stats and performed spectrum analysis during the times of high noise.  I can't find anything abnormal.  I'm not seeing higher levels of utilization, interference, increased interferers, CCI, ACI,retries, etc.  I'm really struggling with this one.  Any ideas?

 

These are AP-225s, 7210 controllers, running 6.4.

#7210
#AP225

Also, I may need a bit of an 802.11 lesson here.  I just recently caught the noise floor spike, but was able to correlate that with an increase in channel utilization on that AP.  A client started a large file transfer resulting in a lot of traffic.  What I don't understand is why this is classified as noise to the AP when it's traffic to/from it.  I thought noise was strictly a measurement of non-wifi interference and interference from other devices (not associated to that AP).

What command are you using to measure the noise, and what version of ArubaOS is this?

 

 

I'm observing from the GUI dashboard.

 

AOS 6.4.2.4

I would use the command:

show ap debug radio-stats ap-name <name of ap> radio 0 advanced | include Noise

Current Noise Floor                 97

 

hi thecompnerd

what version of 6.4 are you using exactly ?

regards

-jeff

6.4.2.4

noted... I need to resurrect a discussion with R&D about this, it has been seen before (it is a false reading). I'll get back to you over next few business days, or ping me at my forum name @ aruba.

regards

-jeff

Thanks Jeff. I remember seeing this as a bug a while ago.

The only supporting evidence I have is a spectrum recording while the noise
floor was high. I can provide that if it would be useful.