No virtual switching (via Frontplane Stacking = VSF or via Backplane Stacking) is supported on Aruba 2530/2540.
To deploy VSF you need at least Aruba 2930F or bigger Aruba 5400R zl2 with v3 zl2 Modules.
Backplane stacking (dedicated Hardware Stacking module and Stacking Cables) instead applies to Aruba 2930M and Aruba 3810M only.