A much asked question these days, is Exchange supported in a virtualized environment? As in many cases, the answer is “it depends”. Microsoft supports virtualized Exchange under the following conditions:

• Hardware virtualization software used is one of the following products:
  • For Exchange 2007 or Exchange 2010: Windows Server 2008, Windows Server 2008 R2 with Hyper-V, Hyper-V Server 2008 or Hyper-V Server 2008 R2;
  • For Exchange 2003: Virtual Server 2005 R2;
  • In general, any validated 3rd party hypervisor (check for ESX, XenServer versions etc.). Click here for the list.
• Exchange guest
  • Exchange 2003 SP2 (or later)
    • Virtual Machine Additions and Virtual Machine PCI SCSI driver required;
    • Exchange 2003 clusters aren’t supported;
  • Exchange 2007 SP1 (or later)
    • is running on Windows Server 2008;
    • support for Windows Server 2008 R2 expected with Exchange Server 2007 SP3 (no date announced yet);
    • No Unified Messaging role (due to real-time requirements by UM role);
    • Meets all of the Exchange 2007 SP1 specific requirements (here).
  • Exchange 2010
    • is running on Windows Server 2008 SP2 or Windows Server 2008 R2;
    • No Unified Messaging role (due to real-time requirements by UM role);
    • Meets all of the Exchange 2010 specific requirements (here);
    • HA features (DAG) aren’t supported in combination with virtualization clustering or high-available solutions.
  • Earlier versions of Exchange than Exchange 2003 are not supported