VMware GSX Server 3.1 includes experimental support for AMD Opterons, although not for guest operating systems Historically, VMware has been the top choice for x86 server virtualization. VMware provides an abstraction layer on top of a host OS, permitting multiple virtual server installations (called “guests”) on a single host system. The VMware GSX Server product is a robust server solution, providing multi-user remote console access, health and resource monitoring, and access to more RAM than the Workstation product.GSX Server 3.1 adds support for Microsoft Longhorn Beta and Solaris x86 Versions 9 and 10. More importantly, it’s VMware’s first release to include nascent 64-bit support, giving it a leg up on its new competition: Microsoft’s recently acquired Virtual PC.Installing guest operating systems under the new version was as straightforward as ever. The multi-user console support is great and the management tools have come a long way, although the Web-based management interface seemed to have some library linking issues under 64-bit Red Hat Linux. This release also includes VirtualCenter 1.1, a Windows-based application for managing virtual machines across multiple host OS platforms. Overall, the software installed and ran beautifully on a four-CPU 2.2Ghz Opteron 848 server loaded with the 64-bit version of Red Hat Advanced Server 3.0. Guest operating systems can only use a single processor under GSX Server, however, and you’ll want to disable Hyper-Threading because guests can only make use of a single thread on Hyper-Threading CPUs. What’s more, although the new version can support multiple 32-bit guest operating systems, we’ll have to wait to run 64-bit code as a guest OS.To be fair, VMware’s official statement is that 64-bit support for GSX Server 3.1 is experimental. As such, although the product is stable enough for production applications, it’s probably best suited for development and QA purposes.— Paul Venezia Technology Industry