How to build a virtual Exchange test lab

You won’t need many physical servers to run your virtual Exchange test lab, but you will need at least one host machine. Your own laptop will work fine; just make sure it has plenty of memory. The number of VMs you’ll require to create your virtual lab will vary based on your testing requirements and how closely you plan to mimic your Exchange production environment.

At a minimum, you should have the following:

• Two Exchange VMs - These can be used in a variety of combinations. Place one of the servers in a virtual demilitarized zone (DMZ) and use it as an edge transport server.
• Active Directory and a domain name system (DNS) server.
• Shared storage (storage area network [SAN]/network-attached storage [NAS]) - This can be a virtual storage appliance (VSA) running as a virtual machine. If you use this configuration, you don't need a physical SAN/NAS solely for your test lab -- more on that later.
• Exchange client – This can be something as simple as a Windows 7 virtual desktop running Microsoft Outlook.

Virtual Exchange test lab formats
You can create a few different Exchange test labs using virtualization:

• A large Exchange lab. You will need two physical servers and a small SAN/NAS (such as an Iomega IX4-200D). Each physical server will run either VMware ESXi or Microsoft Hyper-V. If each server has eight GB of memory or more, you could potentially get more than 10 VMs on each server. With this configuration, you can test Exchange in a virtual environment and will still have enough room to add more VMs to your lab.
• Using this format you can also test vSphere features like vMotion, distributed resource scheduler (DRS) and VMware high availability. Similarly, if you use Hyper-V, you can test Live Migration.
• A medium Exchange lab. You will need one physical server running ESXi or Hyper-V and have the option to use a SAN/NAS. While this setup is too small to test advanced virtualization features with Exchange, you’ll still have plenty of capacity to run several Exchange-related VMs.
• Running ESXi or Hyper-V will result in good performance and capacity, but if you choose to offload the storage onto a dedicated SAN/NAS, you'll get better performance and will have plenty of room for VM snapshots.
• A small Exchange lab. If all you have is a single PC or laptop, you can still create a useful and inexpensive virtual Exchange test lab. To do so, you need a Windows OS and VMware Workstation or Virtual PC on your machine. With this configuration, you can run three or more VMs depending on the amount of RAM available on your machine.
• You also have the option to consolidate your Exchange VMs beyond recommended best practices, although you may experience slow performance.

Virtual Exchange test lab hardware and software checklist
Here are some hardware and software recommendations for a virtual Exchange lab:

• Physical server. Make sure that your physical server has a 64-bit CPU that supports Intel virtualization technology or AMD virtualization. I recommend getting as much memory on that server as possible (at least eight or more GB).
• Examples of servers to consider are the Dell T610 or the HP Proliant ML110. Even if you're going for the small Exchange test lab and using a desktop PC or laptop, the CPU and memory recommendations remain the same.
• Storage. As I mentioned earlier, if you go with the large lab you will need to purchase a small NAS/SAN. If you go with the medium lab, it is optional. Either way, storage doesn't have to cost a fortune. You can buy a network file system (NFS) or iSCSI-capable NAS/SAN for under $1,000. My Iomega IX4-200D works well in my own lab.

• Hypervisor. You must use either VMware vSphere or Microsoft Hyper-V on the server. Administering your hypervisor with VMware vCenter or Microsoft System Center Virtual Machine Manager (SCVMM) is ideal, but optional. You can get away with VMware's free ESXi (the VMware vSphere hypervisor) or free Hyper-V (Hyper-V Server 2008).
• If you want to test more advanced virtualization features, you'll need to check out commercial hypervisors like the full 60 day vSphere evaluation. If you choose to run your Exchange VMs on your desktop or laptop (small lab), you can buy VMware Workstation or use the free Microsoft Virtual PC, depending on which hypervisor you’re using.

• Exchange software. If you’re an Exchange admin, you already have Exchange. If not, you can obtain a 120-day evaluation of Exchange. Alternately, you can purchase a TechNet subscription and run Exchange in your lab indefinitely. Another option is to download already installed Exchange 2010 virtual machines. However, they only run under Hyper-V or Virtual PC. Finally, you'll also need the Windows Server OS that you will install Exchange on.

The benefits of a virtual Exchange test lab
After getting your virtual Exchange test lab pieces in place you'll be able to learn about and test Exchange in ways that aren’t possible in a production environment. For example:

• Snapshots. You can take a snapshot of Exchange VMs, make configuration changes -- or installations -- check the results and then "snap-back" to the point in time before you made the change.

• Cloning. You can clone virtual machines and duplicate entire Exchange virtual machines. This lets you quickly duplicate Exchange VMs and even duplicate your lab environment.

• Replicate your actual Exchange environment. Let's say you’ve already virtualized Exchange. You can now restore backups of those VMs in a private virtual network and make changes to your Exchange infrastructure in your lab environment.

Even if you haven't virtualized Exchange, you can perform a one-time physical-to-virtual conversion of your Exchange infrastructure to virtualize it. From there, you can take snapshots of those VMs and test configuration changes on virtual machines that are identical to your production servers.

About the Author
David Davis is the author of the best-selling VMware vSphere video training library from Train Signal. He has written hundreds of virtualization articles on the Web, is a vExpert, VCP, VCAP-DCA, and CCIE #9369 with more than 18 years of enterprise IT experience. His personal Website is VMwareVideos.com.