Every day, an increasing number of organizations are considering Exchange 2010 virtualization projects, largely because virtual environments are easier to provision, maintain and protect. And while any of the "big three" hypervisors from Citrix Systems, Microsoft and VMware can adequately support Exchange Server 2010, IT administrators should take a close look at VMware. Its vSphere product has been around the longest, has the biggest...
share of the virtualization market and provides advanced features worthy of a world-class hypervisor.
Why VMware vSphere for Exchange 2010 virtualization?
VMware's vSphere has been successfully virtualizing Tier-1 applications like Microsoft Exchange before Hyper-V was even created. Longevity alone doesn't make it a better choice, but the flexibility, reliability and maturity of its features are the reasons it's become the favorite among many Exchange administrators.
For more on virtualizing Exchange
Check out our Exchange Server virtualization 101 guide
My company first virtualized Exchange 2007 on VMware ESX Server when Microsoft didn't recommend virtualizing Exchange at all. We moved from a single physical server running Exchange 2003, supporting 2,000-plus users, to four Exchange 2007 virtual machines running on VMware in a distributed resource scheduler cluster across multiple hosts.
Our Exchange Server virtualization project made Exchange more available, resolved performance issues and gave IT flexibility like being able to use virtual machine snapshots and vMotion. That was more than four years ago and the virtualized Exchange deployment is still running today, with no server downtime.
Of course, every situation is different. Run a cost and feature comparison from your own perspective to ensure vSphere is the right choice. In some situations, licensing costs or bundled pricing could make Microsoft or Citrix tools a better option.
The cost of vSphere for Exchange 2010 virtualization
Cost is a major consideration of course, but don't make it the lone factor when choosing a hypervisor. Free or small-business versions of vSphere, XenServer and Microsoft Hyper-V are typically unsuited for virtualizing Exchange Server 2010. Compare the list prices for the Enterprise editions of Microsoft Hyper-V and VMware vSphere:
- Microsoft Hyper-V -- Windows Enterprise 2008 R2 will cost you around $3,999.
- VMware vSphere -- vSphere Enterprise Plus will cost you around $3,495.
Sticker shock aside, let's look beyond price and consider licensing. A Windows Server Enterprise 2008 R2 license lets you run four Windows virtual machines (VMs) at no additional cost but lacks the advanced features of VMware vSphere.
VSphere Enterprise Plus doesn't include any Windows guest OS licenses, though it does include features such as storage distributed resource scheduler (SDRS), hot-add virtual CPU (vCPU) and RAM, eight-way virtual symmetric multiprocessing (vSMP), storage and network I/O control as well as several advanced-memory management techniques.
When you consider that Windows gives you four Windows OS licenses, but vSphere gives you more advanced features, the value for what you pay is similar. Microsoft Hyper-V costs less, but you also get less.
Think about the scope of your decision. Chances are you're not just choosing a virtualization platform to virtualize Exchange; you'll also want the same homogeneous hypervisor in your data center.
If you haven't done any server consolidation yet, you may really be choosing the hypervisor for your entire data center, not just Exchange Server 2010. In this case, a Windows shop may make a strong cost case for Hyper-V, while some shops may be willing to have heterogeneous hypervisors (VMware and Hyper-V) to save money.
VMware vSphere features for Exchange 2010 virtualization
VMware vSphere is unrivaled when it comes to advanced features. Here are a few of the big ones:
- VMotion. This feature lets admins move running VMs from one host to another. This prevents downtime and enables distributed resource scheduler (DRS).
- Distributed resource scheduler. The DRS ensures that VMs get the CPU and memory they require to keep applications performing optimally.
- Storage VMotion. Storage VMotion lets admins move virtual machine disk files (VMDKs) for a running VM from one storage array (or logical unit number) to another.
- VMware High Availability (VMHA). VMHA restarts VMs that were on a failed host or restart VMs when the operating system hangs.
- Storage Distributed Resource Scheduler (SRDS). The SDRS relocates the virtual disk files of a running VM when that storage is performing poorly or running out of disk space.
VMware vendor ecosystem
The vendor ecosystem and user-community support are factors worth considering when choosing a hypervisor.
A strong ecosystem brings innovation via strong community feedback about a product. Strong products also bring resources like blog posts, community forums, user groups and passionate administrators who want to share their success.
Editor's note: Watch for part two of this virtualizing Exchange Server 2010 with VMware vSphere series.
ABOUT THE AUTHOR
David Davis is the author of the VMware vSphere video training library from Train Signal (including the new vSphere 5 video training course). With more than 18 years of enterprise experience, Davis has written hundreds of virtualization-related articles for the Web and is a vExpert, a VMware Certified Professional, a VMware Certified Advanced Professional-Datacenter administration, and Cisco Certified Internetwork Expert #9369. His personal website is VMwareVideos.com.