This error message means that the controller received a discovery request through a broadcast IP address that has a source IP address (given), which is not in any configured subnets on the controller. It also means that the controller dropped the packet. This typically happens when the u trunks all allowed VLANs instead of restricted them to wireless VLANs.
Please allow only specific vlans.
Complete these steps in order to resolve this problem:
1.If the controller is on another subnet, the APs must be primed for the controller IP address, or the APs must receive the controllers IP address using any one of the discovery methods.
2.The switch is configured to allow some VLANs that are not on the controller. Restrict the allowed VLANs on the trunks.