Mike Neil, General Manager for Virtualization Strategy at Microsoft, has wrote up an entry on the Windows Server Division WebLog explaining why Windows Server virtualization (codename Viridian) and Virtual Server 2005 R2 service pack 1 have both been delayed. The public beta of Windows Server virtualization will ship in the second half of 2007, not in the first half as previously disclosed while Virtual Server 2005 R2 SP 1 will be available in Q2, not Q1 as previously stated. In the interim, customers and partners will have the opportunity of downloading a Release Candidate later this month.
The delays are due to Windows Server virtualization being designed to scale across a much broader range of systems: 64bit processors, a much more dynamic VM environment with hot-add of processors, memory, disk and networking as well a greater scalability with more SMP support and memory. Also, Windows Server is being tuned for virtualization to run demanding enterprise IT workloads, even I/O intensive workloads. For the Virtual Server 2005 R2 delay, Neil explains that additional time is needed to test the new operating systems that will be supported with the service pack of Virtual Server R2 (SUSE Linux Enterprise Server 10, Solaris 10 and the recent CTP build of Windows Server "Longhorn"). Virtual Server R2 SP1 will work better on systems with more memory (up to 256 GB) and more cores. Support for hardware assisted virtualization in the form of Intel VT and AMD-V has also been added.
In less than a year, Microsoft has seen more than 15,000 downloads of the Linux add-ins for Virtual Server 2005 R2, which indicates strong interest to consolidate Linux workloads on Windows Server. The recently released Virtual PC 2007 has had over one million downloads in the first 38 days. Windows Server "Longhorn" remains on schedule: Beta 3 is expected this half and RTM in the second half of the year.
News source: Windows Server Division WebLog