Wireless Access

We are trying to use Mode-Aware ARM to reduce CCI in our deployment.

show ap arm history ap-name returns output like:

ARM History
-----------
Time of Change       Old Channel  New Channel  Old Power  New Power  Reason  Result
--------------       -----------  -----------  ---------  ---------  ------  ------
2017-09-13 11:51:48  0            1            0          12         ON      Configured
2017-09-13 11:51:44  11           0            6          0          OFF     Not accepted

We've seen messages that say both 'Not accepted' and 'Overridden' when ARM tries to disable the 2.4 GHz radio.

I haven't been able to find documentation that indicates a setting in the arm or rf profile that would prevent mode-aware ARM from turning the radio off. Profiles can be viewed in the attached text file.

This is using ArubaOS 6.5.3.2 on a 7240 controller.

Thanks in advance!

Attachment(s)

arubaARM.txt   11 KB 1 version

Having the exact same issue running 6.5.3.1, coming from 6.4.4.9 where it worked perfectly.  Have an open TAC case for this.

ARM mode aware is very unpredictable.  Back in the day, it would be an easy way to turn off 2.4ghz access point radios if you really had too much coverage.  Frequently it would turn off too many access points and leave you without coverage in areas that you would need it.  It supposedly would detect an "edge" access point in your network and not turn it off, assuming you would need that on.  It would be slow to turn access points back on dynamically if coverage was reduced.  It never really worked the way it was intended and is more trouble that it is worth.

In the present day it would be far better to just lower the power on the 2.4ghz band by lowering the ARM min and max TX power.  If you wanted to manipulate ARM mode aware it is controlled by manipulating the Ideal Coverage Index, the Acceptable Coverage Index and the free channel index.  Unfortunately, that will also change how your access points are distributed, and what channels they are on.  I would never advise changing those parameters from the defaults in a typical environment, however.

Please see the ARM supplement here:  https://community.arubanetworks.com/aruba/attachments/aruba/unified-wired-wireless-access/7592/1/ARM%20Doc%20Supplement.pdf for more technical information about ARM.

Thank you for your reply.  We have a very dense deployment built for 5 GHz capacity and our 2.4 is way over baked.

It's disappointing that the solution is to turn off the feature.  The promise of a dynamic channel plan delivered via ARM was a big reason that we paid a premium for the Aruba solution.

With power levels, the best practice is to give ARM a range of 6 dBm to work with.  At that point, you've practically set a static TX power. 

At least it does do a good job of changing channels to avoid CCI, because if it didn't, we'd be all the way back to static channel plans.

If we now need to go back and manually turn off half of our 2.4GHz radios, we are one step closer to a static channel plan, and we have 2 AP groups to manage per residential building - Not the end of the world, but not really ideal, either.

We are working with our VAR and SE to move a case through TAC - we are told that it's been escalated to development.

I do appreciate your time and well thought out response/workaround.  None of this is intended to be sarcastic, mean, or a personal attack (you do a great job providing a lot of help on these forums!) - but it is my honest perspective as a customer who's been told 'That feature doesn't work, don't use it.'

My view is not that the feature doesn't work;  It has limitations and might not be appropriate for what you are trying to use it for.  Maybe tac or professional services can come up with a plan that satisfies the needs and the performance of your deployment.

In addition to the radios not disabling I'm also finding that the EIRP levels are not reducing even though the ARM history shows that it reduced it to 3.  For example, one of my AP-groups in a dense convedntion center environment right now has a mix of old AP-105s and recently installed AP-335s, the ARM profile has a Min 3 Max 6 transmit EIRP and the 335s are stuck at a 7.6 EIRP.  This information has been added to my TAC case which as of yet is not resolved, escalated to engineering.

(TX-Master-Primary-1) #show ap active | include EX-E

EX-E-PRE-1         TX-EX-E            10.42.202.154  0            AP:HT:11/7.6/24.0    0            AP:VHT:36/15.0/28.5    335      A2da   11d:22h:34m:39s  N/A

EX-E-8             TX-EX-E            10.42.202.96   0            AP:HT:1/7.6/25.0     0            AP:VHT:40/15.0/28.5    335      A2da   11d:23h:19m:55s  N/A

EX-E-PRE-2         TX-EX-E            10.42.203.77   0            AP:HT:1/7.6/25.0     2            AP:VHT:52/15.0/25.0    335      A2da   8d:19h:4m:28s    N/A

EX-E-2             TX-EX-E              10.42.202.93   0            AP:HT:11/7.6/24.0    0            AP:VHT:112/15.0/25.0   335      A2da   11d:23h:20m:50s  N/A

EX-E-1              TX-EX-E            10.42.202.102  0            AP:HT:6/7.6/25.6     3            AP:VHT:132/15.0/24.5   335      A2da   11d:23h:18m:42s  N/A

EX-E-7              TX-EX-E            10.42.202.97   0            AP:HT:1/7.6/25.0     0            AP:VHT:136/15.0/24.5   335      A2da   11d:23h:19m:34s  N/A

EX-Marble-Cubby      TX-EX-E              10.42.202.161  0            AP:HT:1/7.6/25.0     0            AP:VHT:132/15.0/24.5   335      A2da   11d:22h:33m:54s  N/A

EX-E-5             TX-EX-E            10.42.202.99   0            AP:HT:11/7.6/24.0    0            AP:VHT:108/15.0/25.0   335      A2da   11d:23h:19m:14s  N/A

EX-E-4             TX-EX-E            10.42.202.94   0            AP:HT:1/7.6/25.0     0            AP:VHT:149/15.0/28.5   335      A2da   11d:23h:20m:22s  N/A

TX-LS-Bridge-FedEx  TX-EX-E            10.42.202.192  0            AP:HT:6/6.7/24.7     0            AP:VHT:60/15.0/25.0    225      A2da   37d:8h:6m:14s    N/A

EX-E-6              TX-EX-E              10.42.202.95   0            AP:HT:6/7.6/25.6     0            AP:VHT:64/15.0/25.0    335      A2da   11d:23h:20m:19s  N/A

EX-E-3              TX-EX-E              10.42.202.101  0            AP:HT:11/7.6/24.0    0            AP:VHT:48/15.0/28.5    335      A2da   11d:23h:18m:50s  N/A

(TX-Master-Primary-1) #show ap-group TX-EX-E

AP group "TX-EX-E"

------------------

Parameter                                Value

---------                                -----

Virtual AP                               Gaylord-Conventions-AP-Profile

Virtual AP                               iGET

Virtual AP                               WPA2_8-VAP

802.11a radio profile                    EX_RadioA

802.11g radio profile                    EH_RadioG

Ethernet interface 0 port configuration  default

(TX-Master-Primary-1) #show rf dot11g-radio-profile EH_RadioG

802.11g radio profile "EH_RadioG"

---------------------------------

Parameter                                      Value

---------                                      -----

Radio enable                                   Enabled

Mode                                           ap-mode

Adaptive Radio Management (ARM) Profile        EH_ARM_g

(TX-Master-Primary-1) #show rf arm-profile EH_ARM_g

Adaptive Radio Management (ARM) profile "EH_ARM_g"

--------------------------------------------------

Max Tx EIRP                                                                  6 dBm

Min Tx EIRP                                                                  3 dBm

 recently installed AP-335s, the ARM profile has a Min 3 Max 6 transmit EIRP and the 335s are stuck at a 7.6 EIRP

it may be the case that the lowest possible conducted power the AP can go to (non negative, probably 2 or 3dBm), plus the built in antenna gain adds up to 7.6dBm EIRP (which includes the gain). You can take a look in the 'show ap debug driver-log ap-name <ap>' to see if that's the case (look for some line that shows the conducted, ant gain and power, sorry I don't have the ability to generate a sample as I post this).