Storage tiering has largely been a manual or semi-automatic process to date, but the momentum behind sub-LUN automated tiering in block-based storage systems could start to drive greater interest in solid-state drives (SSDs).

In this tutorial on automated tiering, we outline the sub-LUN offerings the major storage vendors are promoting alongside their SSD options. We also explore five questions users need to consider as they evaluate sub-LUN tiering options. Finally, we spotlight the case study of an early adopter, Princeton Radiology Associates P.A., and its use of Dell Compellent Technologies Inc.'s Data Progression auto-tiering software to illustrate some of the reasons why policy-based control and monitoring tools can be so important.