* Digging into Windows Server 2003 virtual server
One of the exciting features in Windows Server 2003 is the “virtual server.” This technology allows multiple operating systems (or multiple instances of one operating system) to run on a single hardware platform. Among the reasons you might want to run virtual servers are: cost savings on hardware (i.e., fewer boxes); consolidation of “real estate” and management (i.e., reduced headcount); and legacy applications (i.e., those that require an older operating system).
Using one hardware platform means fewer monitors, keyboards, network cards, power supplies, disk drives and most other hardware associated with servers. Today’s server hardware can support the large amounts of RAM and drive space that virtual servers might need, so why buy extra boxes that you don’t need?
Extra boxes which, by the way, need electrical supplies, cooling and heating and (I hope it goes without saying) locking server rooms. Since “server room” is often a euphemism for closet, too many boxes can quickly cause heat problems not to mention the problem of where to stack them. More server rooms mean additional management personnel – or, more probably, more work with no increase in staffing.
Legacy applications, in this case, refers to earlier Windows platforms but also Macintosh and Unix services. The concept is still the same, though: fewer boxes taking less space and needing fewer managers.
Just as Microsoft sought out expert help when it first launched Terminal Services (licensing the technology from Citrix rather than developing it), it saw no need to re-invent virtual technology which was already present in the marketplace. Instead, Gates & Co. licensed the virtual machine technology of Connectrix.
Connectrix is no Johnny-come-lately, either. It got started in the “virtual” business in 1988 with a product called, appropriately, “Virtual.” This was among the first virtual memory products (now a part of almost all operating systems) to swap portions of RAM to disk to give the appearance of lots more RAM than you actually had. In 1997, it introduced the first virtual machine, an application for the Macintosh platform that allowed users to run Windows programs on the Mac OS. Virtual PC for the Mac is still available, as is Virtual PC for Windows along with Virtual Server, but all will now be maintained and sold by Microsoft.
With Windows 2003, virtual server technology is but one of three suggested methods for consolidating services. The others are hardware partitioning and workload management. Hardware partitioning is a method to house multiple physical servers within a single box by dedicating a portion of the CPU, RAM and disk to different applications running on different instances of the operating system. Blade servers, for example, are an extension of this method. Workload management is the term applied to the technology involved with SQL Server 2000 that allows multiple instances of the database engine to run on a single hardware platform under one instance of the operating system.
Each of these technologies has a place in an enterprise network. Hardware partitioning can reduce the number of single points of failure, for example. Workload management offers much of the advantage of virtual servers but is only useful if the application and/or service is designed to use the technology (such as SQL Server 2000). But if you want to run Windows Server 2003 yet still have an application that requires NT 4 Server, then a virtual server arrangement offers your best choice.
Read “Server Virtualization in the Enterprise” (https://www.microsoft.com/windowsserver2003/techinfo/overview/virtualization.mspx) then decide how this technology can best be put to use in your organization.
