Can the controllers in a mobility domain run on different codes?

[Muhammed Adnan]

Dear Experts,

Can different 5500 WLCs in a mobility domain configured for N+1 redundancy run on different software versions? IMO there should not be any issues but still wanted to confirm.

I have a setup of six 5500 series wireless LAN controllers and over a thousand 1262 Wireless Access Points, all configured in same mobility group and with N+1 redundancy. 

The problem is, all of them are running on a software version that is already declared deffered by Cisco i.e 7.6.120.0. 

I am wanting to upgrade these WLCs as I have added 1572 APs  in my setup which require code 8.0, but owing to the criticality of site and its 24/7 operation, I would not be allowed to change the code on all in a single go.

Planning to upgrade atleast one wlc for now, and then in preceeding months to other WLCs. 

Please suggest, if my approch is safe.

Best Regards,

Adnan

[Sandeep Choudhary · Accepted solution]

HI Adnan,

In N+1 sceanrio:These WLCs are independent of each other and do not share configuration or IP addresses on any of their interfaces. Each WLC needs to be managed separately, can run a different hardware and a different software version.RegardsDont forget to rate helpful posts

[Muhammed Adnan]

Hi Sandeep,

Thank you very much for your prompt response :)

Thanks,

Adnan

[Scott Fella]

The only thong you must make sure of, is that you have the high availability set on the access points.  When you have different code versions running, because you need to upgrade, like your doing, you need to make sure AP's don't move around to the various controllers, which can cause you issues.  When I have to upgrade a customers controllers and its one at a time, then I would change the mobility group name and will not add any controllers to that new group and I would also remove the upgrade mobility information on the other controllers.  I dont' want any chance of AP's moving and upgrading.  However, you will not have redundancy until you upgrade antoher controller, you will not have roaming if you have AP's on the new and existing controllers in the same roaming area.  Keep this in mind.  You can also use mac friltering to only allow AP's that you have added the mac address to the controller to only join.  I have used this option also.

I would not use another controller as a backup, N+1, if the code version is different.

Here is a link to the compatibility for mobility:

http://www.cisco.com/c/en/us/td/docs/wireless/compatibility/matrix/compatibility-matrix.html#pgfId-149658

-Scott

[Muhammed Adnan]

Hello Scott,

Glad to see your response. 

Can you please elaborate a little more on your below point?

However, you will not have redundancy until you upgrade antoher controller, you will not have roaming if you have AP's on the new and existing controllers in the same roaming area.

If the WLC are running on different code in N+1 redundancy then clients would not be able to have inter-controller roaming? In that case, it is not as simple as is suggested by sandeepchoudhary21  

The site is having APs from different controllers scattered around, I fear I run into more bad than good :). Waiting for you more valuable inputs coming in