Correction to article in TechNet Newsflash June 5th
This article states that OCS is not supported in a virtualised environment. Since the initial draft of the article, the support stance changed. Some OCS Server roles can now be deployed in a virtualised environment:
Presence, Instant Messaging (including remote access, federation, and Public IM Connectivity) and Group Chat workloads are supported. The following server roles can be deployed virtually:
· Front-End Servers
· Back-End SQL Server 2008 64 bits
· Group Chat Channel Servers
· Group Chat Compliance Servers
· Edge Access Servers
The virtual machines must be running on Windows Server 2008 64 bits. Archiving Server and Monitoring Server (CDR Only) can be connected to a virtualized Enterprise pool, but they must run on a physical server. The virtualised deployment must meet the requirements of the Microsoft Server Virtualization Validation Program (SVVP) - https://www.windowsservercatalog.com/svvp.aspx?svvppage=svvp.htm
For more information, consult the OCS team blog - https://communicationsserverteam.com/archive/2009/05/13/488.aspx . A capacity planning whitepaper accompanies this announcement - https://www.microsoft.com/downloads/details.aspx?FamilyID=0a45d921-3b48-44e4-b42b-19704a2b81b0