WLC 5520 OS upgrade in HA

[Herman2018]

Hi, we have one pair of cisco WLC 5520 in HA setup, now need to upgrade from 8.5 to the latest version OS, can anyone please help advise the detailed steps of this upgrade? thanks in advance!

[Kasun Bandara · Accepted solution]

@Herman2018 check this article.

https://networkproguide.com/how-to-upgrade-cisco-5520-wlc-3802-ap-software/

[Herman2018]

thanks a lot @Kasun Bandara  for your hep!

[Mark Elsen]

 - FYI : https://www.cisco.com/c/en/us/td/docs/wireless/controller/technotes/8-7/High_Availability_DG.html#pgfId-83293

 M.

[Herman2018]

Thanks a lot @Mark Elsen @Leo Laohoo for your kind advice and help!

[Leo Laohoo]

Read the Release Notes. 

The complete instruction is there. 

There are also vital information that can be crucial to the success (or failure) of the upgrade.  

If there are any question(s), then ask here.

[Rich R]

And refer to the TAC recommended link below for selecting the version to upgrade to.
Also check the compatibility matrix to make sure all your APs will be supported on the new version.
If all new(ish) APs then 8.10.185.0 is current latest.  If you have older APs then you might need to look at 8.5.182.7.

[Herman2018]

@Rich R , thank you so much for your advice! 

[Rich R]

You're welcome @Herman2018