As of Service Pack 1, which just entered beta testing this week, Microsoft has committed to support Linux as one of the supported guest operating systems on its Virtual Server 2005 product. Microsoft has not said that Linux cannot run as guest with the current Virtual Server release. But currently, the list of sanctioned operating systems for which Microsoft provides support as "guests" is relegated to Microsoft operating systems. SP1 provides support for 64-bit host operating systems including 64-bit versions of Windows Server 2003 and Windows XP, significant performance enhancements, built-in support for network installations of guest operating systems (PXE boot), and several other features. Virtual Server 2005 SP1 beta is available to testers at http://beta.microsoft.com with the guest id "vssp1BetaTester" and the final version is slated for release by the end of the year.

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