According to a report on CNET News.com, Microsoft today will reveal that its upcoming server virtualization software, Virtual Server 2005 R2, will be made available to customers for free. The current version costs either $99 or $199, depending on the number of supported processors. Virtual Server 2005 R2 will allow corporations to run guest operating systems in special software-based virtual machines under the host server. It will compete with products such as VMWare Server, which will also be made available for free.

Also new from the Microsoft camp is a sudden resurgence in Linux support. When Microsoft initially developed its Virtual PC and Virtual Server products, both of which are based on technology acquired from Connectix, the first thing the software giant did was remove any official support for running Linux virtual machines. Now, however, after a few years of customer complaints, Linux support is back, and Microsoft says that it has even developed methods for more easily installing popular Linux distributions in Virtual Server-based virtual machines. The company will even support customers that wish to run Windows and Linux virtual machines side-by-side on the same hardware.

"We’ve made a long-term commitment to make sure that non-Windows operating systems can be run in a supported manner, both on top of Virtual Server and our future virtualization products," says Windows Server director of product marketing Zane Adam. Additionally, Microsoft is working to build virtualization services directly into the next Windows Server version, currently codenamed Longhorn Server and due in 2007.

Microsoft's Virtual Server moves are timed to coincide with the start of LinuxWorld in Boston this week. Though Microsoft is a staunch opponent of Linux, the company has been opening up to various Linux interoperability and migration scenarios over the past few years.