Wireless Access

 View Only
Expand all | Collapse all

5 GHz channels reporting incorrectly.

This thread has been viewed 29 times
  • 1.  5 GHz channels reporting incorrectly.

    Posted Feb 13, 2025 03:20 PM

    Don't trust Airmatch or reported values. Validate with other tools like Ekahau or Aruba UXI sensors!!

    First posted mid January 2025

    We have two clusters, each cluster has two 7240XM controllers. Cluster is L2 connected. Environment is managed by an active Mobility Conductor. We have a standby MC.Everything is running 8.10.0.14.  TAC Case open for issue noted below. We are advised by Aruba ERT engineer that they are escalating issue to a higher level engineering team. TAC has confirmed our findings during multiple remote session. HPE/Aruba has not sent anyone onsite.

    The issue:

            Airmatch is not honoring 5GHz channel assignment as defined in AP groups. In addition, and most worrisome, the channels reported by the MD, MC and Airwave may be incorrect. This is not restricted to any one specific AP group, cluster or location. We have multiple AP groups configured across out hospitals. Standard AP group settings allow all 5 GHz channels except channels 36,144,165. We only use 20 MHz channel width.

           We discovered Airmatch (or maybe some other protocol) is assigning channels 36 and 165. We suspect channel 144 is also being assigned but have not confirmed that with Ekahau or the Aruba UXI sensors. TAC has confirmed our findings. We can prove 100 % that an AP is using channel 36 (match BSSID) per UXI and Ekahau  whereas the Aruba infrastructure, MDs, MC and Airwave all report the AP is using another channel. Example, Aruba infrastructure may show the AP on channel 64.

           When we associate a Win11 device or a Vocera badge, we see channel 36 displayed on GUI of each yet the Aruba infrastructure shows the client is connected to the channel the Aruba infrastructure is reporting the AP is using, say channel 64 to use the example above.

    1/31/25 - After three weeks of troubleshooting and multiple remote sessions with multiple TAC Engineers,  this issue is being tracked via internal ticket# AOS-262499. 

    2/6/25 - Request by TAC. Uploaded ap tech support files from 3 additional access points that are reporting incorrectly.

    2/113/2025- How to confirm actual channel in use:

    Run below to find the channel reported to be in use. Note radio is reporting it is using channel 140

    show ap active ap-name <valid ap name>  - 

    Active AP Table
    ---------------
      Radio 0 Band Ch/EIRP/MaxEIRP/Clients 
            AP:5GHz-VHT:140/18.0/25.2/2         

    Run below command to find the channel the radio is actually using. In this case, radio 0 of the access point is actually using channel 36 while the channel reported by the mobility conductor and MDs report the radio is on channel 140. 


    show ap debug radio-info ap-name <valid ap name>    

    Radio Info Script
    ------------------
    aruba_dbg_radio_info_0 Start time: Wed Jan 29 11:58:41 EST 2025
    ---------------------------------------------------------------

    ====== wl-commands ======

    wl -i wifi0 cca_get_stats -i
    Using channel 36
    chan dur      ibss           obss           interf       time
    36  1002   85  8% Low       0  0% Low       0  0% Low    3521950
    36  1002  100  9% Low       1  0% Low       0  0% Low    3521949
    36  1002  197 19% Medium    2  0% Low       0  0% Low    3521948
    36  1002   97  9% Low       1  0% Low       0  0% Low    3521947
    36  1001   91  9% Low       1  0% Low       0  0% Low    3521946
    36  1003  100  9% Low       5  0% Low       0  0% Low    3521945
    36  1002  111 11% Low       2  0% Low       0  0% Low    3521944
    36  1002   70  6% Low       1  0% Low       0  0% Low    3521943
    36  1002   77  7% Low       1  0% Low       0  0% Low    3521942
    36  1002   75  7% Low       1  0% Low       0  0% Low    3521941
    Summaries:
    chan dur      ibss           obss             interf     num seconds
    36  1002      10% Low          0% Low          0% Low    10
    Recommended channel: 36



  • 2.  RE: 5 GHz channels reporting incorrectly.

    Posted 25 days ago
    Edited by Vignljv 25 days ago

    Latest update from HPE Support Case 5387240686 

    Hi Lenny,

    Greetings. We have got a response from our engineering team regarding the root cause and the fix version.

    Root cause: Due to an intermittent timing condition within the system, the channel assignment process can occasionally experience a discrepancy. This refinement to the system's internal synchronization logic ensures consistent channel allocation, effectively preventing the reported mismatch. Our testing confirms this resolves the observed behavior.

    Regarding the fix, this will be fixed in 8.10.0.17 version.

    As it will take a long time to release 8.10.0.17, I have requested for Cbuild for time being till the fix version is out. I am yet to get an update on the Cbuild. I will keep you posted once I get an update.