Microsoft announced today that Windows Server 2008 R2 Hyper-V will be able to run CentOS, the popular free Linux distribution for Web servers. CentOS is one of the top three most popular Linux distributions for Web servers, and could account for as much as 9% of the Web whose host OS information is available, according to a 2010 study.

Therefore, said Sandy Gupta, General Manager of Marketing for Microsoft's Open Solutions Group, support for CentOS was the most frequently requested interoperability addition from the community of hosters and service providers.

Previously, SUSE Linux Enterprise Server 10/11 and Red Hat Enterprise Linux 5.2+ were the only Linux distributions officially supported on Microsoft's server virtualization platform.

With this update, available immediately, mixed Windows + CentOS infrastructure can be merged under Windows Server Hyper-V just as it could with SUSE or Red Hat.