In a project as complex as storage virtualization, selecting a vendor is one of the most important steps. Typically the decision will be strongly influenced by considerations such as pre-existing relationships and the installed base of equipment. But you'll be living with the results of your virtualization decisions for a long time to come, so there are several things you should consider in selecting the major vendors for your virtualization effort. IBM has put together a list that offers a good starting place.
For example, it's a good idea to see the virtualization environment actually working, either at the vendor's site or in a third party-installation. This should include actual demonstrations, benchmarking and other indications that this is a here-and-now solution, not something that's still being developed.
Testing is critical to a successful virtualization effort and the best time to start testing for things like interoperability is before you buy. You want to make sure that the virtualization products work well together and integrate smoothly with your existing infrastructure. Ideally you want an extensive test program to make sure that everything works at the expected performance levels. That takes a lot of testing.
In a similar vein, ask to see the vendor's road map for storage virtualization projects. Virtualization is anything but a one-time deal and both your requirements and the technology are going to be evolving. Of course road maps are speculative documents and generally firmly engraved in jelly, but you're much better off working with a vendor who is at least thinking about where they're going with virtualization than with one that's making it up as they go along. A good road map should include both technology and market considerations in a coordinated approach. Ideally you want a virtualization vendor who is in the game for the long haul, knows where they're going and whose future plans match your expected needs.
Related to the road map is a commitment to research and development. The company should be putting substantial resources into developing future generations of products and, ideally, showing a commitment to such expenditures over the history of the company.
Of course you want to avoid getting locked in to a vendor. That means you want to see demonstrated open standards capability as well as a corporate policy of commitment to open standards. It's important that your virtualization products work with products from other vendors.
IBM discusses all this in a document titled "Storage Vendor Selection Guidelines" on its Web site.
Rick Cook has been writing about mass storage since the days when the term meant an 80K floppy disk. The computers he learned on used ferrite cores and magnetic drums. For the last twenty years he has been a freelance writer specializing in storage and other computer issues.