Cisco WLC 5508 to 5520 Migration

[nick.smethurst1]

Hello Everyone,

I am looking for some advice on the best way to migrate from a single 5508 to a 5520 (I know this is an old bit of kit but it's only temporary solution to enable us to replace a number of AP's before migrating again to a newer WLC)

We have the 5520 on the network with configuration added albeit a different management IP and a later version of code. The plan for migration is disconnect the 5508 and change the 5520 IP to that of the 5508 that's in production. Should the AP's recognize it's a different controller with the same IP and then re-register with the 5520?

Having never done this before, any advice whether this should work? or if there is a better way of doing this?

[marce1000]

  - Well , I think they must at least reboot (the APs) ; also take care of https://www.cisco.com/c/en/us/td/docs/wireless/compatibility/matrix/compatibility-matrix.html
    make sure that all current APs are compatible with the software being used on the 5520

   + Have a checkup of the 5520 controller's configuration using WirelessAnalyzer input (procedure) for AireOs controllers
     and feed the output from that into   Wireless Config Analyzer
                                                 (ABOVE CORRECTED FROM INITIAL REPLY!)

  M.

[Flavio Miranda]

Hi @nick.smethurst1 

 It would be very important to keep the exactly same version on 5520 as the 5508, this would avoid unecessary code download and install on the AP.  The AP will reach the 5520 and will register just fine and the downtime will be minimum if they dont need to download and install a new software.

  Of course, a safer approach would be add both WLC to the network and migrate on per AP basis. 

[marce1000]

   @Flavio Miranda  : I would like to add to your remarks in the following context :
                                https://www.cisco.com/c/en/us/support/docs/wireless/wireless-lan-controller-software/200046-tac-recommended-aireos.html
                                 For the  5520 this comes down to using 8.10.196.0 (preferred)
                                 If there is an image upgrade 'to pay for' on the APs I consider it acceptable (I think it won't
                                 take that long)   because
                                 the aireos controllers are being phased out and using  the last-advised release is recommended
                                                                 (just my thoughts)

  M,.

[Rasika Nayanajith]

If both WLC on the network safer approach would be migrating APs from one WLC to another. You can move few APs and test your SSIDs first. If everything is good you can do bulk migration by changing AP primary (new WLC) and secondary (old WLC) settings via old WLC CLI.
Even the WLC versions differ, this method will give you full confidence how long single AP will down during the migration.

HTH
Rasika
*** Pls rate all useful responses ***

[Haydn Andrews]

Make sure you take into account the field notice for MIC certificates, you may need to roll the clock back on the 5520 depending on version running currently on the 5508 and use the mic ignore command

[Rich R]

Exactly as Haydn - you didn't mention what software versions you have running on the WLCS @nick.smethurst1 
Refer to the field notices below to make sure you don't get caught out.
And as Marce said - check the APs are compatible with the software version in the Compatibility Matrix.