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

Exchange 2003:

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

Exchange 2007

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

Exchange 2010:

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)

Common notes:

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.

MTC Part Two

Back at the Microsoft Technology Center here in NYC for another day of hands-on Exchange 2007 setup work.  We're presenting tomorrow on both Exchange and SharePoint protection with Double-Take Software (see disclaimer below), and today I got to finalize the environment and test failover and failback.  Of course, failover and failback worked perfectly, but I was really impressed with the new Hyper-V systems that we're using to create and run the demos.

So far they've handled all of the Exchange stuff the exact same way as physical servers, including the failover and failback processes that call for Active Directory and WMI updates along with starting and stopping Exchange services on one or both machines.  Since the system is automated, the changes happen rapidly.  On physical servers, this doesn't pose a problem, but sometimes virtual machines (sharing processors and RAM) can get bogged down.  That has not been the case here, with the Hyper-V VM's staying responsive and moving fluidly through the entire process.

Granted, you probably wouldn't put the DC/DNS Server and both the production and failover Exchange servers on the same Hyper-V host in a production environment.  But, it is nice to know that it can be done.

Hyper-V is relatively easy to use if you're familiar with the current virtualization tools on the market from a variety of vendors.  For Exchange 2007 on Server 2003, the VM's behave exactly the same as a physical box would with the same software set - as you would expect from a VM tool.  What is different is the speed at which they reboot.  Even with Exchange 2007's extended boot-up time, the average reboot took only 1-2 minutes, as compared to 3-5 minutes for physical boxes and other VM platforms.  This could just be a quirk of the environment we're building in, but that's still a fast boot up.

In terms of configuration, the GUI interface for Hyper-V allows for the standard set of server definition variables.  You select file locations for the definition files and the virtual hard disks, set the amount of RAM, processors, etc, and then boot the VM.  For these servers, we used cloned Windows 2003 Enterprise installs taken from other VM's already built, but you can boot from a virtual CD-ROM or any physical boot media the host can see attached to itself.

From there, as expected, the server behaves much like a physical box, loading the OS and rebooting as required.  Once you're up and running on a Supported OS, you can install the Hyper-V Integration Services via a virtual CD-ROM.  This enhances mouse and keyboard integration and opens up several dozen options - such as the ability to share folders between the host and the guest.

Networking options follow the standard set of VM options, including the ability to create Host-Only networks that can't see the outside world, or bridge physical adapters from the host to the guests.  This is especially helpful for Exchange, as you could create a Host-Only network between the Mailbox role servers and the Hub/Transport and CAS role servers, while giving the latter another interface to the outside world.

We're using a combination of virtual disks and physical disks, so I did not get a chance to play around with the Snapshot features - which require that all volumes be on virtual disks to function properly.  I've done snaps of Exchange 2007 servers with other tools with a good success record, and I was hoping to try it with Hyper-V too.  That'll have to wait for next time.

Oh, before I forget, though we'll be in the Grand Central Briefing Center, this MTC has an Envisioning Center as well.   It's a theater-like room that showcases all the latest (and even some upcoming) Microsoft products.  And sure enough, they have a working Surface unit that I got to play with.

You can find more info on what Surface is (and I really suggest checking it out) at this link.

Tooting our own horn time!

Double-Take Software's virtual systems tools (Virtual Recovery Assistant, Double-Take for Virtual Systems and Double-Take for Virtual Infrastructure) are up for Readers' Choice awards at SysCon!  As most of my readers know, I work for Double-Take Software, so I am jazzed about another potential award for us.  Back to the Exchange stuff shortly, but in the meantime, you can find out more and vote here:

Virtualization Readers Choice Awards sponsored by Sys-Con

Link to voting at http://virtualization.sys-con.com/general/vote.htm

Here are the categories we were nominated in:

· Best Application Virtualization – Double-Take and VRA

· Best P2V Migration – VRA

· Best Virtualization Platforms high Availability – VRA, Double-Take for VMware Infrastructure, Double-Take

Hyper-V-active Exchange

As most folks have already seen, Hyper-V - the newest Microsoft Virtual Server Solution - released to market yesterday.  This is a pretty big step forward for MSFT, adding a datacenter-ready virtualization solution to the Server 2008 platform.

I'm doing a little research now on the Exchange front with Hyper-V, but I was able to get an un-named source (ooooh spooooky) from MSFT to confirm that some MSFT Exchange 2007 servers at their facilities are running on Hyper-V, so support on that platform will most likely be forthcoming.  More info on this front as I can get my hands on it.

From the limited contact I've had with the betas, I can safely say that this product is a different animal than Virtual Server 2005.  The overall performance in both the Host and Guest components has ratcheted up by a factor of multiples, The management interface is also re-designed to allow for more fine-tuned control over the vitalized systems, and cluster support means the ability to move VM's between hosts is built-in.

We're still in the very early stages of this technology, so expect more reports as I run into it more and more in the field.  Within a short period of time, I'm also going to get to put Exchange 2007 through its paces on Hyper-V, and I'll be happy to report on that too!

It goes without saying that Double-Take is going to be supporting Hyper-V in the very near future with some amazing tool sets.  If course we can already replicate and fail over Exchange from Physical or Virtual (of any flavor) into a Hyper-V VM, but keep your eyes peeled to find out what new stuff we're working on over here especially for the Hyper-V platform.