I recently installed a new 5520 WLC with 1500 AP licenses. I have 400+ APs currently associated to this controller and have been adding more. Recently, I have had issues with new APs joining this controller. Many instances I have seen the APs trying to connect to the controller, but after making the join request, it gets a send fatal message and then continues to go through the process of trying to join and getting a send fatal. The controller shows that the AP is trying to join, and it has the failed to delete database entry error. I have attached the output from the AP Join messages from the controller.
There is not a country code issue, and there are 1500 AP licenses on the device, so that should not be an issue. Any thoughts as to what is going on? thanks in advance.
