Hyper-V Me (Yes, Even for Exchange)
Due to the release of Hyper-V R2, there has been a lot of buzz about using Microsoft’s Virtualization Platform to create virtual machines for everything in the datacenter from file servers to high-capacity databases. There are quite a few systems that are clearly ok to use virtualization with, but Exchange Server has always been one of those platforms where virtual tech has been a questionable course. Not the least of the reasons for this is that folks have been confused on if MSFT supports running Exchange in production on a virtual platform. So, I’ll spell out the current support stance as found on official MSFT sites only. Note: There are many blog postings that point one way or the other, so I have hunted down official MSFT sites to quote here (i.e. TechNET, MSDN, etc). While many blogs can be trusted (like the official Exchange Team Blog at http://msexchangeteam.com – and http://www.BeingExchanged.com of course), many of my readers have corporate policies about needing to see the documentation from a MSFT site directly; and so here it is:
Exchange 2000 and earlier:
Not supported for production environments. See the end of the TechNET article found here: Link to TechNET
Supported in production. Warnings are given that you must use Virtual Server (2005 R2 or higher) and that there are some performance limitation to be considered. Link to TechNET
Supported for production environments on Hyper-V, but with some limitations. You must be running Server 2008 as the Guest OS, and you have to be running Exchange 2007 SP1. Unified Messaging may not be run on a Hyper-V Guest. You cannot use both SCR and/or CCR and Hyper-V clustering at the same time. Finally, the virtual machine itself must meet all the hardware requirements (processors, RAM, etc) for Exchange 2007 Sp1. Link to TechNET
Supported for production environments on Hyper-V, with some restrictions: You must be running Server 2008 SP2 or R2 as the Guest OS, and Unified Communications Roles are not supported at all. As with 2007, the virtual machine you install Exchange into must meet all the hardware requirements for Exchange 2010. You will also need to choose between DAG availability or Hyper-V failover solutions, you cannot run both at once. Link to TechNET (see section on Hardware Virtualization)
In all supported versions, certain functions of the virtualization systems are not supported with Exchange Server. Specifically, dynamically expanding virtual disks are not allowed, you have to use pre-configured fixed-sized VHD’s for Exchange Server virtual machines. Likewise, you cannot leverage differencing or VSS snapshot disks if you’re running Exchange Server.
There are several rules about virtual hardware that you must follow as well, so read the related TechNET articles for guidance on things like disk types (SCSI, IDE, etc) and the like.
Hyper-V technology is bringing new opportunities to the virtualization technologies platform in the modern datacenter. By clarifying what is and is not supported in a virtual environment, Microsoft has begun the process of allowing customers to safely start using virtualization for the Exchange Server platform. Many users will still choose physical hardware for Exchange (either because they cannot meet one or more of the requirements, or just due to having hardware already provisioned), but these rules help clarify that options for virtualization exist and are supported.