Refer to the exhibit.

The issue described in the scenario occurs because when creating an Access Control List (ACL) to be used for managing traffic to the Wireless LAN Controller’s (WLC) CPU, it must be explicitly defined as a CPU ACL. If this specification is not made during the creation process, the ACL will not appear in the drop-down list when enabling the CPU ACL function. This is necessary because CPU ACLs are used to protect the WLC against potential Denial-of-Service (DoS) attacks by filtering incoming packets directed at the management interface before they are processed by the CPU. References: CCNP Enterprise Wireless Design ENWLSD 300-425 and Implementation ENWLSI 300-430 Official Cert Guide