WLC upgrade AP ?

[Network Pro]

Hi 

I would like to upgrade my controller to 7.4.x.x and i have about 1500 AP's - just wondering once i upgrade the controller and reboot wil all my 1500 AP's have their software upgraded at the same time ? what is the process the AP's will upgrade their software ? can i schedule it at a later time for them to upgrade or schedule it batch by batch ?

Thanks

[Network Pro]

sorry about this, think i pressed the button twice !

any thoughts on this please ?

[Scott Fella]

There is a feature on v7.0, pre-image download, you can review it here:

http://www.cisco.com/c/en/us/td/docs/wireless/controller/7-0/configuration/guide/c70/c70mfw.html#wp1132291

This only works on access points with 32mb of flash, so the older access points like the 1242, 1131, it will not work.  What you do is upload the image to the WLC and issue the pre-download.  This way when you reboot the WLC, the downtime is minimized because the access points have the image already.  If you don't have supported ap's, then it will take a while.  How long, I couldn't tell you but to be safe, I would say an hour, depending on where the aps are located geographically due to WAN throughput.

-Scott 

[Network Pro]

Thanks Scott - so do i have to click on preload image on each and every AP or is there a simpler way to pre - image the AP

also how many concurrent upgrades can the wlc7500 handle ? and how long does it take for each ap to upgrade the software if i were to go by the wlc reboot method ?

Thanks

[Scott Fella]

First, make sure you upload the image to the WLC and on the GUI, go to the Wireless tab then Global Configuration.  Toward the bottom, there is a button "Download Primary".  Click that and then go back to the Wireless tab and wait.  You will see if you scroll to the right, that the access points either are downloading the image, successfully downloaded or failed.  You can do this way ahead of time and just let it run overnight if you wish.  Depending on your WAN, it could take a while.

When you decide to reboot the WLC, I say around 5-10 before the ap's come back.  They have to join the wlc and then they will be forced to reboot and come back up.

-Scott

[Network Pro]

Hi Scott,

so please correct me if i am wrong

first way: update the firware on the wlc and when the AP's reload they get the new firmware - i understand for 5508 the concurrent upgrades is 500 AP's so what will happen to the rest ?

second way - pre-image the AP's with firmware version before i upgrade the WLC and on reboot the AP's, the ap will reload with new firmware version ? is there a way i can pre-image all 1500 AP's on cli rather than going on GUI and clicking on "Download Primary"

Another Scenario - we have resilliant controllers so when we upgrade the primary WLC and reload wlc then wont all AP's rejoin the back up controller running the older version ?