Virtualization in the Wintel space first became prevalent with VMware's introduction of its VMware GSX Server in 2001. Then, Microsoft launched Virtual Server in 2004. Today, there are several other virtualization solutions available and virtualization is making substantial inroads in the small-to-midsized business (SMB) market beyond its early toeholds in the enterprise market.
I'll be honest. I don't have a lot of direct professional experience with virtualization. Sure, I know the basics of using Virtual Server. It's an invaluable way to have multiple sandboxes on your primary "work" machine. But I don't have a lot of experience using Virtual Server to host multiple virtual machines (VMs) running SQL Server in production on a single physical machine. Server-consolidation needs drove the earliest rounds of virtualization for production. Initially, most customers consolidating in this way were looking to consolidate dozens—and often hundreds—of SQL servers, each running on a separate machine, into a substantially smaller number of "big iron" data center–style servers. In general, most SMB customers I've run across over the years have tended to use virtualization as a means of effectively handling certain development and testing needs when they didn't have enough physical servers. However, I haven't seen much SQL Server–based Virtual Server usage for SMB production applications. I think the general consensus has been that the management of virtual servers is hard, but managing a smaller number of physical servers is actually easier. And for the most part, SMBs believe it's easier to manage and control SQL Server performance if you have an instance of SQL Server installed on a physical machine rather than in a virtualized environment.
However, I've been seeing a lot of press coverage about virtualization usage in the SMB space lately, although not necessarily around virtualized SQL Server and database usage. In addition, Microsoft is making substantial improvements to its virtual server technology that will ship as part of the upcoming Windows Server 2008.
Is SQL Server in a virtual world poised to move beyond the massively large data center and development, testing, and quality assurance roles in the SMB space? I don't expect a rapid move in this direction because the management tools for both Microsoft's and other vendors' virtualization products still aren't quite up to snuff. But the technology is alluring. My sense is that customers want virtualization to work and want to adopt it. Who wouldn't prefer to have just one or perhaps a handful of servers hosting dozens of servers? I'm curious. What do you think are the main impediments to adopting virtualization technology in the SMB space today? Do you think virtualization is poised to become a widely adopted technology, or will it remain a somewhat niche solution for the foreseeable future?