Although the product has been available at various stages in its development, Microsoft has now finally and officially released their "thin" Microsoft Hyper-V Server 2008. Available as a server role in most editions of Windows Server 2008, Microsoft is also making available a new edition of Windows Server 2008 called Microsoft Hyper-V Server 2008. This Windows Server edition provides an entry-level foray into the world of Hyper-V, but does not provide all the bells and whistles that are available when the Hyper-V role is used with other Windows Server 2008 editions. Further, the licensing model for this Hyper-V Server is quite different than for Windows Server 2008.
Clarification: Microsoft Hyper-V Server 2008 is not Windows Server 2008 edition. It's a new, standalone product. Don't confuse this product with Windows Server 2008 editions on which you install the Hyper-V role.
Microsoft Hyper-V Server 2008 is not intended for large, complex deployments. In fact, Microsoft Hyper-V Server 2008 does not scale beyond four processors and 32GB of RAM, but the Hyper-V server itself can support up to 192 guests. The processors can be multicore units with up to four cores each, meaning that your Microsoft Hyper-V Server 2008 server can have up to 16 cores, making it more than suitable for smaller organizations or branch offices with simple virtualization or server consolidation needs. Guests built on Microsoft Hyper-V Server 2008 can be provided with up to four virtual processors each. Microsoft Hyper-V Server 2008 can support up to 128 guests on the single server. You are far more likely to run up against the 32GB RAM barrier long before you get to 128 guests.
One great benefit that Hyper-V - in all its forms, including this standalone server form - has over VMware ESX server is in the realm of hardware compatibility. Whereas VMware ESX has relatively limited hardware support, Hyper-V servers rely on underlying Windows drivers to work their magic, thus greatly expanding the set of supported hardware. For organizations undertaking serious virtualization projects, however, hardware compatibility is not generally an issue as Tier 1 vendors are common. In smaller organizations, however, Hyper-V's expanded hardware compatibility may be a great benefit.
I should point out the following:
- Microsoft Hyper-V Server 2008 is intended to compete directly with VMware ESX Server 3i
- The Hyper-V role under Windows Server 2008 Enterprise or Datacenter is intended to complete directly with the full VMware ESX Server
Keep these distinctions in mind as you compare the products.
On the management side, Microsoft Hyper-V Server 2008 ships only with command line-based management tools. If you want more robust GUI-based tools, you will need to acquire either System Center Virtual Machine Manager or the Hyper-V Manager MMC snap-in available for both Vista SP1 and Windows Server 2008.
As I've indicated, Microsoft Hyper-V Server 2008 is intended to be an entry-level product. As such, it does not support the high-end availability features that would be included when using the Hyper-V role on a full edition of Windows Server 2008 Enterprise. If you want clustering capability for high-availability, Microsoft Hyper-V Server 2008 is not the right product.
Microsoft Hyper-V Server 2008 does support some protection and limited availability features, including BitLocker encryption support and "Live Backup" which backs up guest virtual machines with no downtime. Both of those features are welcome in a free product, particularly Live Backup.
Just about any reasonable server can be purposed to Microsoft Hyper-V Server 2008, but the actual configuration depends on your need. The physical server itself must have at least one 2 GHz processor, 1 GB RAM, and 10 GB of disk space. Obviously, these requirements are for the server itself and would be wholly inadequate for any kind of guest workload. In addition to these base requirements, be mindful of the server requirements for each of your guests, which you must add on to these requirements.
On the storage front, if you can attach it to your server, Hyper-V can use it. From direct-attached storage to an iSCSI SAN to the highest end Fibre Channel, your server can make use of whatever you attach. Heck, you could even attach a 1TB USB drive to your server and use that if you wanted to. Even network attached storage is usable.
Licensing & cost
Microsoft Hyper-V Server 2008 is free! You can download it from Microsoft and install it without having to use a product key. Once installed, you will need to install guest machines and operating systems in order to make your Hyper-V server useful. Bear in mind that the Hyper-V installation does not include any guest machine licenses. A full Windows Server 2008 installation does includes guest Windows licenses, as outlined below.
- Microsoft Hyper-V Server 2008: All guest Windows Server virtual machines require a separate license.
- Windows Server 2008 Standard Edition: Includes the host plus one additional Windows Server virtual machine guest license. Additional guests must be separately licensed.
- Windows Server 2008 Enterprise Edition: Includes the host plus four additional Windows Server virtual machine guest licenses. Additional guests must be separately licensed.
- Windows Server 2008 Datacenter Edition: Includes the host plus unlimited Windows Server virtual machine guest licenses. Only non-Windows guests require separate licensing, if necessary.
You cannot upgrade from Microsoft Hyper-V Server 2008 to any edition of Windows Server 2008. If you outgrow the Microsoft Hyper-V Server 2008 system, you must migrate your virtual machines to a full Windows Server 2008 server using the provided management tools. Guests built on Microsoft Hyper-V Server 2008 are compatible with the Hyper-V role on a full Windows Server 2008 installation.
My question to you: If you are working in a small environment, will you give Microsoft Hyper-V Server 2008 a run for its money or will you go with the established product in the space: VMware ESX 3i.
Since 1994, Scott Lowe has been providing technology solutions to a variety of organizations. After spending 10 years in multiple CIO roles, Scott is now an independent consultant, blogger, author, owner of The 1610 Group, and a Senior IT Executive with CampusWorks, Inc. Scott is available for consulting, writing, and speaking engagements and can be reached at firstname.lastname@example.org.