Quoting from the Centrify official announcement:
Centrify Corporation, a leading provider of Microsoft Active Directory-based auditing, access control and identity management solutions for non-Microsoft platforms, today announced it has joined the Citrix XenServer Technology Provider Program and has added support for the Citrix XenServer platform version 4 in its flagship solution, Centrify DirectControl.
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Using DirectControl, XenServer administrators can now seamlessly leverage Microsoft Active Directory to centrally control access to their XenServer deployment and use DirectControl’s cross-platform extensions to Microsoft Group Policy to globally manage key security and configuration settings on those servers.
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Centrify DirectControl 4 is available now and supports Citrix XenServer 4.0.1 Express, Standard and Enterprise editions. Pricing for DirectControl for XenServer begins at $350 per XenServer, with similar pricing for Linux virtual guests…