I am working on migrating our existing 1142 and 3502 AP's from WISM1's to our new 5760 controllers by floor/vlan and I'm not sure what I'm missing. I changed option 43 for the vlan of AP's to be migrated and rebooted the AP's however they continue to join the old controller. The WISM is running 7.0.230 code and the 5760 is running 3.3.0 XE code. New AP's out of the box joing without any issue. I haven't yet had a chance to console into an AP to see what is happening.
Option 43 won't force AP to go & register a particular controller. It will simply annonce your 5760 to your AP, but AP always keep record of previously known WLC.
You have to change Prmary, Secondary controller information under AP High Availability tab in order to specify primary & secondary controller for those AP. Try it & see whether AP goes & register to your 5760.
Since brandnew AP does not have any previously known WLC info, it will go & register with your 5760 without this primary & secondary info.
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