This article explains how to trigger the AP image preload on the controller to minimize the downtime during the controller upgrade.
Feature Notes : The AP image preload allows the Access points (AP) to download the new image from the controller where it is terminated before the controller actually starts running the new version, hence reduces the downtime for the controller upgrade.
We can allow all the APs terminated on the controller or custom list of AP groups or individual APs to preload the image.
If a new AP associates to the controller when the preload feature is active, based on the AP group or AP name if it appears in the preload list the AP will start preload its image.
Environment : This feature is only supported on the 3600, 7200 Series and M3 controllers and applies to controllers running OS version 6.3 or later.
Network Topology : Standalone Master, Master-local
Configuration Steps :
1. The controller should be upgraded first and before reboot, we need to trigger the AP image preloading in the same partition where the controller is upgraded.
(Aruba7240) #show image version———————————-Partition : 0:0 (/dev/usb/flash1) **Default boot**Software Version : ArubaOS 6.3.1.3 (Digitally Signed – Production Build)Build number : 42233Label : 42233Built on : Tue Feb 11 12:31:53 PST 2014———————————-Partition : 0:1 (/dev/usb/flash2)Software Version : ArubaOS 6.3.1.2 (Digitally Signed – Production Build)Build number : 41362Label : 41362Built on : Wed Dec 18 17:12:20 PST 2013
(Aruba7240) #show ap image-preload-statusAP Image Preload Parameters
—————————
Item Value
—- —–
Status Inactive——————
-To enable the AP image preload using the CLI, use the following command on the enable mode:
(Aruba7240) #ap image-preload activate ?
all-aps Activate image preload for all registered APs.
specific-aps Activate image preload for specific APs as specified
by ‘ap image-preload ap-group’ and/or ‘ap
image-preload ap-name’(Aruba7240) #ap image-preload activate all-aps partition 0
2. Once the controller is rebooted, the APs will reboot along with the controller and come up with less downtime as the image is already preloaded.
The ap image-preload will go to inactive state automatically after the controller reboots.3. For the controller’s next upgrade, again we need to upgrade the controller first and then need to trigger the AP image preload.
Note: The ap image preload must be inactive and should be triggered only after the controller image upgrade.
Verification : The same can be verified using the following commands:
(Aruba7240) #show ap image-preload-status
AP Image Preload Parameters
—————————
Item Value
—- —–
Status Active
Mode All APs
Partition 1
Build 41362
Max Simultaneous Downloads 10
Start Time 2014-03-18 12:05:04AP Image Preload AP Status Summary
———————————-
AP Image Preload State Count
———————- —–
Preloaded 1
TOTAL 1AP Image Preload AP Status
————————–
AP Name AP Group AP IP AP Type Preload State Start Time End Time Failure Count Failure Reason
——- ——– —– ——- ————- ———- ——– ————- ————–
MasterAP Master 10.10.10.252 105 Preloaded 2014-03-18 12:05:04 2014-03-18 12:06:15 0(Aruba7240) #show ap image-preload-status-summary
AP Image Preload Parameters
—————————
Item Value
—- —–
Status Active
Mode All APs
Partition 1
Build 41362
Max Simultaneous Downloads 10
Start Time 2014-03-18 12:05:04AP Image Preload AP Status Summary
———————————-
AP Image Preload State Count
———————- —–
Preloaded 1
TOTAL 1(Aruba7240) #show ap image versionAP Image Versions On Controller——————————-6.3.1.2([email protected])#41362 Wed Dec 18 16:16:17 PST 2013Access Points Image Version—————————AP Running Image Version String Flash (Production) Image Version String Flash (Provisioning/Backup) Image Version String Matches Num Matches Num Mismatches Bad Checksums Bad Provisioning Checksums Image Load Status— —————————- ————————————— ———————————————— ——- ———– ————– ————- ————————– —————–10.10.10.252 6.3.1.2([email protected])#41362 Wed Dec 18 16:16:17 PST 2013 6.3.1.3(p4build@port-royal)#42233 Tue Feb 11 11:29:58 PST 2014 6.1.3.4-3.1.0.0(p4build@cyprus)#35320 Sat Sep 15 13:43:44 PDT 2012 Yes 1 0 0 0 DoneTotal APs:1