for controller based APs to be managed by Aruba Central, they need to be converted to AOS10 APs.
AP-305 is not one of the APs that is supported.
Here is the Supported Devices for AOS 10.x
https://www.arubanetworks.com/techdocs/AOS10_3_OLH/Content/aos10x/overview/supported-devices.htm------------------------------
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Any opinions expressed here are solely my own and not necessarily that of HPE or Aruba.
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