Force AP to register with another controller

[xuanhuymai]

All,

I have 2 WLCs. One with newer IOS version than the other. All of APs are currently register with older IOS version WLC and of course have the older IOS version. My goal is to force all the APs re-download and re-register with newer IOS WLC. If I don't free up the WLC before IOS upgrade; wireless network will be interrupt and of course I would like to avoid as much as possible. I tried these:

On each AP and under High Availabilty tab; I changed the Primary Controller to the newer IOS WLC ip address; then reset or clear all the configuration; but after came up; APs still register to the older IOS controller.

On DHCP scope option 43; I only have the newer IOS WLC ip address and then reset the AP; it does not work as well.

I guess APs refer the controller that has same version of IOS; regardless of the High Availability setting or the ip address of the controller in the DHCP scope.

Any thought?

[weterry]

If you clear the config from the AP, it wont have the high availability config anymore (but then Option 43 should be helping it out).

Anyhow, the best approach is set the primary name and IP of the WLC you want, and either turn on AP fallback, or reboot the AP. If that AP is not joining the Primary WLC, then you have some kind of problem....  Because that is as easy as the procedure goes...

Perhaps you could console into an AP and record what output happens when you do this?

And better yet, if I were supporting this, I'd be looking to see "debug ip udp" from the console of the AP to see exactly what packets are sent and recieved (a packet capture from the AP switchport would work just as well).

[Scott Fella · Accepted solution]

This is pretty simple. A couple other things is to make sure you don't have master controller enabled on the WLC with the old code. Verify that your mobility between the two WLC is up, AP fallback on both WLC is enabled. If everything is setup as mentioned, change the primary WLC on the AP to the WLC with the new code and either wait a couple minutes or just reboot the AP. You do not need option 43 or dns for this.

Sent from Cisco Technical Support iPhone App

[xuanhuymai]

Leolaohoo,

I changed the ip address and Primary controller name under High Availability; but it did not work.

But, with Scott Fella's method, it works just fine. I just need to set the newer code controller as master, then reset APs in other controllers. No downtime needed. Thank Scott.

[Scott Fella]

One thing to note if the AP's didn't join unless you set the WLC as master WLC, is to make sure the Primary Controller name is correct.  This entry is case sensitive.  Glad you got it working.

[Leo Laohoo]

On each AP and under High Availabilty tab; I changed the Primary Controller to the newer IOS WLC ip address

Only the IP address?  Hmmm ... Are you, by any chance, running 4.X firmware?

[Comm Team]

The solution provided by Scott Fella worked for me as well. Setting the WLC as Master Controller helped to move the APs.