AP staged upgrade WLC 9800

[sirajuddeen t p]

Hi Support team,

I have a requirement to replace current 5508 WLC HA cluster to 9800 WLC at customer DC. The access points are distributed in different countries and centrally managed from the DC WLC. As far as I know the APs will start upgrading as soon as they are registered to new WLC. Is there a way we can prevent this and do staged upgrade. I checked document "High Availability using Patching and Rolling AP Upgrade on Cisco Catalyst 9800 Wireless Controllers". Does it covers migration of APs to new WLC? or it is only possible for the APs currently active under the 9800 WLC?

It would be great help if there is a step by step approach you can share.

Thank you.

[Scott Fella]

My bad @sirajuddeen t p didn't read the other rpost you had on upgrades.  Here is my 2 cents.  I have always prefered N+1 and that is how I have been deploying 9800's and even AireOS.  SSO works fine, it just that you have to really understand SSO and the downtime to make changes or possible have to break SSO is why I prefer N+1.  I can tell you with N+1 and being part of the EFT on newer beta code that rolling upgrade has worked and works well.  This would be the same as SSO, except a few steps extra for N+1.  

What you can do if you have a vmware environment or hyper-v is to spin up a few 9800-CL's in SSO and in N+1 and just go through some of the steps to setup SSO and you can also start with a lower code version and upgrade slowly so you can be comfortable in explaining to your customer how to perform an upgrade or ISSU or installing a patch, etc.  

In the end, you need to make sure your customer is successful and you are not just deploying something and handing that over to them in which they have no idea how to support that.  

[sirajuddeen t p]

Thanks Scott for the advise. I will certainly follow the recommendation. I will go ahead with the N+1 design as per the below since the customer already placed order for two WLCs and additional WLC ordering is not possible at the moment.

[Scott Fella]

Well keep us posted on how it goes.

[marce1000]

              >...the ISSU document says it does not support between major release? 
 - In HA SSO the situation is different because there are two controllers which the APs can fallback on , so it can be done , BUT you must read release notes for targeted release and check if the (direct) upgrade path is possible from current controller version, (that check is always needed HA SSO or not)

 M.

[sirajuddeen t p]

Thanks Marce for the additional information.