Controllerless Networks

Hello,

I currently have 8 IAP 205 access points. How many of them should have the preferred option checked? I didn't know if only the one access point that I want to be the preferred master should be checked so that it's the master. Or if they should all be checked so they are all available to take over in the event that the master goes down? 

Thanks in advance! 

You do not need to enable preferred master on any IAP.  Some people want their Virtual Controller AP to be predictable, so they would enable preferred master on that specific AP.

http://community.arubanetworks.com/t5/Controller-less-WLANs/How-to-enforce-an-member-Instant-AP-as-a-master-in-the-cluster/ta-p/181668