Product and Software: This article applies to all Aruba controllers and ArubaOS versions.
It's a limitation of inside broadcom switch chipset.
The switch chipset has only 2 GE and only max 2 trunk ports.
One GE and trunk port is used by the Sibyte datapath processor. Another GE is on A800. So, there is only one trunk port for the controller.
For A200, there is no switch chipset. Both interfaces are attached to the Sibyte directly. So, we can do trunk on both FE and GE port.
For A2400, A5000/6000, they are using different switch chipset which does not have this limitation. So, they have no trunk limitation.