The DellEMC VMAX3 includes an optional feature called FAST.X, which will virtualize external storage and use it as another tier. FAST.X differs from the earlier implementation of Federated Tiered Storage in that the external storage can be assigned as any tier.
All features of the VMAX are available with FAST.X. The number of host interfaces are reduced by the number of interfaces used to attach external storage.
The VMAX3 adds an additional integrity check called T10DIF to external volumes called eDisks created by VMAX3 on the external systems. Data may be migrated in the background from the external storage systems and may be directly accessed (passthru mode) for data in place.
Dell EMC VMAX3 FAST.X Product Brief Includes: