Saturday, June 5, 2010

AP Image Pre-Download

Starting in WLC code version 6.0, new unified code images can be pre-downloaded to wireless access points to reduce network impact during the upgrade process. The current primary or backup boot images on the controller can be selected to pre-download to the access points.

In addition, each access point now holds a primary and backup image in flash to facilitate failover in the event of a corrupt image and for easier image swapping between multiple versions.

Currently, these features are only available through the controller CLI.

To configure AP image pre-download, perform the following from the controller CLI:


  1. View the current controller images

    show boot

    (cciewlc) >show boot
    Primary Boot Image............................... Code 6.0.188.0 (active)
    Backup Boot Image................................ Code 6.0.182.0
      

  2. View the current AP images:

    show ap image { all | ap-name }

    (cciewlc) >show ap image all

    Total number of APs.............................. 1
    Number of APs
            Initiated....................................... 0
            Predownloading.................................. 0
            Completed predownloading........................ 0
            Not Supported................................... 0
            Failed to Predownload........................... 0

                                            Predownload   Predownload
    AP Name     Primary Image  Backup Image Status        Version      Next Retry Time  Retry Count
    ----------- -------------- ------------ ------------- ------------ ---------------- ------
    CCIELWAP001 6.0.188.0      0.0.0.0      None          None         NA               NA

  3. Pre-download a new primary or backup image to an AP. Specify the controller’s current primary or backup image to pre-download to the AP:

     
    config ap image predownload { primary | backup }{ all | ap-name }

     
    Note – If the selected image is already present on the AP as its primary or backup image, the image will not be downloaded to the AP.

  4. View the progress of the image pre-download:

    show ap image { all | ap-name }

     
    (cciewlc) >show ap image all

    Total number of APs.............................. 10
    Number of APs
            Initiated....................................... 4
            Predownloading.................................. 5
            Completed predownloading........................ 1
            Not Supported................................... 0
            Failed to Predownload........................... 0

                                               Predownload     Predownload
    AP Name      Primary Image  Backup Image   Status          Version     Next Retry Time  Retry Count
    ------------ -------------- -------------- --------------- ----------- ---------------- ------
    CCIELWAP001  6.0.188.0      6.0.182.0      Complete        6.0.182.0   NA               NA         
    CCIELWAP002  6.0.188.0      0.0.0.0        Predownloading  6.0.182.0   NA               NA         
    CCIELWAP003  6.0.188.0      0.0.0.0        Predownloading  6.0.182.0   NA               NA         
    CCIELWAP004  6.0.188.0      0.0.0.0        Predownloading  6.0.182.0   NA               NA         
    CCIELWAP005  6.0.188.0      0.0.0.0        Predownloading  6.0.182.0   NA               NA         
    CCIELWAP006  6.0.188.0      0.0.0.0        Predownloading  6.0.182.0   NA               NA         
    CCIELWAP007  6.0.188.0      0.0.0.0        Initiated       6.0.182.0   NA               0          
    CCIELWAP008  6.0.188.0      0.0.0.0        Initiated       6.0.182.0   NA               0          
    CCIELWAP009  6.0.188.0      0.0.0.0        Initiated       6.0.182.0   NA               0          
    CCIELWAP010  6.0.188.0      0.0.0.0        Initiated       6.0.182.0   NA               0      

  5. Swap primary and backup images on an AP. The AP must be rebooted after swapping images for the new primary image to be used during runtime.

    config ap image swap { all | ap-name }
     


Also, watch for future enhancements to allow image staging off an existing access point or other local TFTP/FTP server. This can reduce image download times to access points by locally staging an image on an AP or server rather than traversing a low-bandwidth, high-latency WAN connection to download the image from a centralized controller.


Andrew

6 comments:

  1. Andrew,
    Thanks for sharing. There is always something new to learn for me.

    Regards,
    /steve williams

    http://www.sudonetworks.com

    ReplyDelete
  2. Thanks for sharing! This definitely helped me out

    ReplyDelete
  3. Nice article... thanks for sharing. Does anyone know if this is supported on the WLC2106? All docs I have been able to google only reference the 4400 and 5500 controllers

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  4. Hi Ken,
    It should also work on a 2106 WLC since this is a code enhancement in software. I have not attempted it on that platform, however, so I cannot be certain. If you test it, please let us know your results.

    Andrew

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  5. Thanks for sharing this.... in the middle of an upgrade now

    ReplyDelete