Microsoft Strongly Hints At Linux Support in Virtual Server 2005
by Alex Woodie
Companies should be able to run X86-based Linux, Unix, and NetWare operating systems on their Wintel machines using new virtualization software that Microsoft expects to ship later this year. Microsoft Virtual Server 2005, which was made available for download in Release Candidate form last week, will come in standard and enterprise versions and will "run most major X86 operating systems," Microsoft says, although the software will be optimized for Microsoft Windows server operating systems.
As Microsoft's mission creeps higher and higher into the enterprise, one of the key pieces notably absent from its Windows Server System is virtualization technology that allows multiple instances of an operating system to run on the same machine. Such virtualization technology has been commonplace for years on high-end Unix and IBM mainframe and OS/400 platforms, and other proprietary midrange machines, and now Microsoft is on the verge of shipping its own virtualization capability.
Last year, Microsoft bought Connectix, which at the time had a virtualization product for PCs and was about to enter beta testing for a server version, called Virtual Server (see "Microsoft Buys Connectix for Virtual Machine Partitioning"). Microsoft originally intended to get the server version of that software, which it called Virtual Server 2004, to market by the end of 2003. Obviously, that never happened, but the distribution of Virtual Server 2005 RC 1 indicates Microsoft is close to shipping a finished product.
As any company that has reined in a sprawling server farm can attest to, there are very good economic reasons to deploy virtualization technology. On established midrange and mainframe platforms, virtualization technology is enabling huge server consolidation and application migration projects, where dozens or hundreds of smaller servers (often Intel servers running Windows or Linux workloads) are consolidated on very large SMP boxes. This can drastically cuts administration costs, and often also decreases hardware and licensing fees. It also drives up utilization rates on servers as workloads are balanced across processors and throughout a daily and weekly cycle. Virtual machine technology also holds the potential to centralize software testing and development onto a single box, supporting multiple versions of a single operating system and even multiple, incompatible operating systems on that machine. This is the area Microsoft is targeting with its first release of Virtual Server 2005.
Microsoft Virtual Server 2005 will come in two flavors: Standard Edition, which will support servers with up to four processors, and Enterprise Edition, which will support the largest 32-way Windows servers. Supported host environments include Windows Server 2003 (Standard, Enterprise, and Datacenter editions); Windows Server Small Business Server 2003 (Standard and Premium editions); and Windows XP Professional (although it cannot be used for production and is intended only for testing). Supported guest environments include Windows NT 4.0 Server SP4 through SP6; Windows 200 Server SP2 through SP4; Windows Server 2003; and "most major X86 operating systems," Microsoft says.
Connectix supported non-Windows operating systems written for X86 systems, including Linux, Solaris, Novell NetWare, and OS/2 operating systems, and it appears very likely that Microsoft Virtual Server 2005 will, too. In its Virtual Server 2005 white paper, Microsoft touts the product's capability to "run most major X86 operating systems," although guest virtual machine environments will be optimized for Microsoft's own fare: Windows Server 2003, Windows 2000 Server, and Windows NT 4.0 Server. It makes perfect sense for Microsoft to support Linux, as well as other competitive X86-based operating systems, such as NetWare. Allowing a Windows server to manage other environments keeps Windows firmly in control of the data center, while providing a protected environment for migrating other workloads to Windows and thoroughly testing them.
As with any virtualization technology, Virtual Server lets users create certain rules that allow the software to govern how memory and CPU resources are to be dolled out. Microsoft recommends at least 256 MB of memory for each guest environment with Virtual Server 2005, while the maximum amount of memory that is to be available to each guest environment can be set (although never reached, if other partitions need them first). The upper limit for the number of guest partitions is dictated by the amount of resources available on the server. The software also allows users to set rules governing allotment of CPU resources, by either "weight" or "capacity." Setting by weight enables users to prioritize the way CPU resources are allocated to virtual machines, Microsoft says, while setting by capacity lets users assign minimum and maximum percentages to be consumed by the virtual machine.
Virtual Server 2005 will run on servers in 32-bit mode using Intel's Celeron, Pentium III, Pentium 4, and Xeon processors, or the Opteron, Athlon, and Duron processors from Advanced Micro Devices. Notably absent from the list is Intel's 64-bit Itanium processor. Microsoft says it is evaluating its 64-bit strategy for future editions of the software; it seems a no-brainer that when the future 64-bit version of Windows for 64-bit Xeons and Opterons is ready this fall, Virtual Server 2005 will be able to support partitions on this iron. The primary competitor to Microsoft Virtual Server in the Windows market is VMware's GSX Server and ESX Server, which is now owned by storage specialist EMC, and this week GSX Server gained 64-bit support on 64-bit Xeons and Opterons. VMware is, however, holding back on Itanium.
Microsoft says that Virtual Server 2005 will be released as a final product later this year. The Release Candidate version is intended primarily to allow third-party developers to test their software against it. Pricing for Virtual Server 2005, which is expected to be very aggressive, will be announced along with the final product later this year, Microsoft says. To read more about Virtual Server 2005, or to download the Release Candidate, go to Microsoft's Web site.