If you have a Mobility Master(MM) all your existing licenses (AP,PEF,RFP) will need to be transferred to the MM using the HPE portal , the MM will be your license server.
For the AP registration configure VRRP for your two controllers and you can point your Aruba-master to that VIP or DHCP option 43
If your controllers are clustered then the AP will only use the VRRP VIP using the initial setup and after it is provisioned the AP will use the node list all your controllers in the cluster
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