we can change the domain that Aruba APs use to look for the controller by using an AP provisioning profile. First, establish your DNS lookup and make sure it works. Next, go to the ap group that you want to have the DNS lookup applied to (Configuration> Wireless> AP Configuration...edit your ap-group). Expand AP and go down to provisioning, which is usually blank. Change the provisioning profile from N/A to new, and then enter your fqdn that you want written to the ap's flash.
If you click on Apply, the hostname.domain.com will be immediately written to the access point's flash and it will be rebooted. When the access point comes back up, it will look for hostname.domain.com, instead of Aruba-Master.
It is definitely worth testing to get the flow right, but you could apply a slightly different provisioning profile to ap-groups depending on the fqdn you want written to the ap's flash. I would test with an empty ap-group first, so that a typo does not render all of your access points unusable. If you DO make a typo, the AP will forever try to find the controller at the fqdn of your typo.
You will then have to (1) Remove the AP provisiong profile from that ap-group, then (2) put the AP on the same VLAN as a controller so it could possibly find it, through broadcasts, to undo the typo..
Positives: - Easily write a different FQDN to the flash of an AP. Don't have to edit your DHCP scope.
Negative: What's written in flash can only be removed if you have a console cable, OR the AP contacts a controller, where it can be removed through the provisioning process...