Refer to the exhibit. An engineer must restrict some subnets to have access to the WLC. When the CPU ACL function is enabled. No ACLs in the drop-down list are seen. What is the cause of the problem?

CPU ACLs apply globally to all traffic destined to the WLC's CPU regardless of which interface it arrives on - there is no requirement to add a Management-interface-specific rule for an ACL to appear in the drop-down.

The WLC's CPU ACL selection drop-down is dynamically populated only from ACLs already defined under Security > Access Control Lists; if that list is empty, the drop-down has nothing to display, and the engineer must first create at least one ACL in that section before the CPU ACL feature can be applied.

No special flag or type designation is needed when creating an ACL for CPU ACL use; any standard ACL created under the Access Control Lists tab automatically becomes selectable in the CPU ACL drop-down.

Cisco WLC fully supports CPU ACL configuration through the web-based GUI under the Security tab, so CLI-only access is not required and is not the cause of the empty drop-down.