I have a support case open right now, running IAP 8.4, If you enable Aruba GRE VPN back to an MD, then also have a Mest Portal and Mesh Point on the network, and enable Per-AP VPN, it seems to create a loop to the MD client VLAN and floods the network. A simple lab with two IAPs in Mesh mode took down our production controller user network. TAC was able to replicate this pretty quickly.
When running Mesh, is Aruba GRE, supported? What about Per-AP VPN? And does the loop prevention mechanisims not work with GRE tunnels?