Microsoft Virtual Server is a visualization solution that helps to create virtual machines on the Windows XP, Windows Vista and Windows Server 2003 operating Systems. It was originally developed by Connectix and later acquired by Microsoft before it was released. Windows Virtual PC’s are related desktop visualization software package of Microsoft. Virtual machines are generally created and managed through an IIS an interface that is web based or it is created by Windows client application tool namely VMRCplus.
Microsoft Windows Server virtualization which was previously termed as codenamed Viridian is a hypervisor based technology that is a part of Windows Server Longhorn. It helps to provide a scalable secure and highly available virtualization platform. It is the main aim of Microsoft to provide the best operating software platform for virtualization.
The current version that is being used is the Microsoft Virtual Server 2006 R2 SPI. Linux guest operating system support is the new feature found in R2 SP1. The new features also include Virtual Disk Pre compactor, SMP, x85-64. It also includes Host OS support which has the ability to mount virtual hard drives on the host OS and other additional operating system including the Windows Vista. The current version provides a volume shadow copy writer that greatly helps in live backups of the guest OS on a Windows Server 2003 or its Host. It also provides a utility to mount images.
Microsoft acquired its unreleased version of the Virtual Server from Connectix in the month of February 2003. The first release of Virtual 2005 came in two editions namely the Standard and the Enterprise. The enterprise version was able to support more processors. Microsoft Virtual Server R2 SPI was able to support both Intel VT IVT) and AMD Virtualization (AMD-V).
Microsoft Virtual Server has its own limitations. Though the Virtual Server 2005 R2 can run on hosts with x86-64 processors, it will not be able to run x64 guests that require x86-64 processors. Though it is able to use SMP it does not virtualize it. The Windows hypervisor is a thin layer of software between the OS and the hardware which allows multiple operating systems to run simultaneously on a host computer unmodified. It helps to provide simple partitioning functions and helps to maintain strong isolation between partitions. It is secure architecture as it does not involve any third party device drivers.
Windows Server virtualization provides an ideal platform for key virtualization scenarios, which include production server consolidation, business continuity management, software test and development of a dynamic data center. It offers scalability, high performance as it supports guest multi processing support and 64 bit host and guest support. It offers reliability and security through its hypervisor architecture. It offers flexibility and manageability as it supports features like live migration of virtual machines from one physical host to another. It also offers dynamic addition of virtual resources and integration with System Virtual Machine Manager.
Microsoft Virtual Server R2 is the current version available for shipping and also available as a free download.