Consolidating your IT resources is usually a key factor in lowering your total cost of ownership (TCO), as well as simplifying the IT environment, which is as complex as it gets. But consolidation for consolidation's sake might not be the best idea. Each IT infrastructure is different and careful analysis is a must to compare consolidation's advantages with total costs, including equipment and personnel costs. The other factor that needs to be considered is the rate of data growth and how it will impact your present and proposed budgets.
Conventional wisdom calls for incorporation of storage area network (SAN) consolidation, network-attached storage (NAS) consolidation, consolidation of tiered resources, and server consolidation. Critical applications aggregated into a SAN can improve service levels, but with a cost trade-off in terms of capital expense and human resource investments. Additionally, what kind of operational performance do your less-critical but still-important applications require?
If you invest in a costly connectivity strategy or already have one on board, these important applications will be lower in your pecking order and suffer a lower return on investment. Implementing a SAN based on iSCSI might improve the ROI picture for those applications. If your NAS devices are spread through countless departments or business units, consolidating them and other general purpose file servers should improve productivity.
Server consolidation certainly makes sense; aggregating applications onto a smaller number of higher-performance hardware with fatter pipes. Naturally, you need to have your data paths well in mind and make sure the consolidation fits into your disaster recovery plan. But storage consolidation, into SAN, NAS, or both, requires a before-and-after type of analysis. And most importantly, you must calculate where your management software leverages. Hardware is just so much metal unless your server and storage management software contribute to the TCO improvement you envision by consolidating resources.