Wireless Access

Hi All, 

Just stumbled on to what I am thinking is a big issue for us. It appears that around a third or half of our AP105 are only using 5ghz instead of using both 2.4 and 5. 

I can't seem to find any information why this is as they are all in the same APgroup/AP profile etc. 

Any thoughts??? hopefuly I missed something obvious......

What info do you guys need from me?

Thanks,

Make sure you don't have any ap-specific profiles

Make sure you do not have ARM Mode Aware On.

Mode aware Arm is indeed on and makes sense. But it presumably turning off the radios for a reason ie interference.

Is it reccomended to be turned OFF?

Thanks for the fast response!

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@fimlewis wrote:

Mode aware Arm is indeed on and makes sense. But it presumably turning off the radios for a reason ie interference.

 

Is it reccomended to be turned OFF?

 

Thanks for the fast response!

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Mode Aware ARM is turning access points off because there is more than enough "coverage" in the area for the SSIDs that you are serving.  Is there a reason why you have it on, in the first place?  Turning it on is not a best practice; The knob was created so that you could easily and quickly turn off radios where you seem to have too much coverage and in turn it would decrease interference.  What it cannot detect reliably is if an access point is on the edge of coverage an NEEDS to be on.  It will turn it off and create a coverage hole.

What kind of construction do you have and how many feet apart are your access points?  In a typical non-concrete structure you typically want them 60 feet apart and staggered from floor to floor...

Mode Aware ARM will disable 2.4GHz if it deems there is enough coverage across the channels (based upon what it is hearing around it from valid APs).  I have only turned it on twice; in both cases we reverted back due to it being too aggressive and leaving some spotty areas on 2.4.   I'd recommend you leave it off unless you feel that your AP deployment is too dense and interfering with eachother.    I'd prefer to turn off lower data rates if possible to decrease the cell size of each AP on the 2.4 radio.

For reference, the following summarizes Mode Aware ARM:

The first problem in mode aware ARM is to detect edge APs, i.e. APs that are in the edge of the building. This is important to ensure that edge APs are not turned off by ARM. This will automatically cause non-edge APs to be turned off if coverage is very high. The AP edge status is determined by the controller based on information received during ARM update messages from APs. This is done based on number of valid APs seen by each AP. The AP with the least number of valid APs seen is classified as an edge AP

• Converting APs to APMs
  • If no active clients AND
  • not an edge AP AND
  • tx-power closer to arm-min than arm-max AND
  • coverage is greater than acceptable on all channels on the band without itself

then transition to APM

• Converting APMs to APs
  • If empty channel available (no interfering APs) OR
  • zero coverage channel available
  • tx-power closer to arm-min than arm-max AND
  • Min covered channel has coverage less than acceptable OR
  • Classified as Edge AP then transition to AP

Hi Guys, 

Thanks for the defn. 

So with it ON I am getting really odd preformance ie for one floor with 7 AP's only one is serving 2.4 and over 30 users are connecting to it. Since our laptops are only 2.4 this is causing some horrible preformance. 

So I will turn it off.

Our main building is 5 floors and each floor has baout 6-7 WAPs and they are spread apart by about 40ft. 

Your other option is to turn down the ARM MAX TX power to 12, turn off ARM mode awareand see if things improve.

Hi Guys, 

Thanks for the tips. 

Mode Aware off

2.4ghz set to 9

5 ghz set to 15

Seems to be making a huge difference and helping with roaming.

After more searching came across increasing "Cell Size Reduction".  Thoughts?

Thanks,