When optimizing infrastructure, storage virtualization for small business is a key consideration given the significant differences in performance and cost of the various options. However, before embarking on the road to comparisons, it is important to consider these three things first:

• Direct Attached Storage does not lend itself to some of the requirements of a virtualized environment  
• One of the benefits of virtualization is the ease with which recovery can be done
• Storage infrastructure should be accessible by more than one server

This leads us down the path of either Network Attached Storage (NAS) or a Storage Area Network (SAN). Nas is a single storage device that may be shared by multiple servers and a SAN is a network of storage devices that may be shared by multiple servers.  Generally for larger storage requirements, a SAN may be more appropriate.

What is interesting is price/performance tradeoff of various options:

Moving from SATA drives to SAS drives significantly improves performance (seek times better than 2x), but come at a substantial price premium.  It is not until the SAN, though, that true storage virtualization is possible.  This provides the maximum headroom and flexibility by allowing dynamic allocation of storage rather than the "stranded" storage that often arises in the traditional approach.

Because of this, if storage growth and flexibilty is important, it is often worth the investment to start with a true storage virtualization strategy as a foundation to other intitiatives. In addition, here are 5 things you should consider before Virtualizing.