Virtual PC was nice for Windows power users. But for developers and systems adminstrators testing against specific OS images and doing similar business-oriented tasks, Virtual Server 2005 is the only thing out of Redmond that might make us stray from VMware. Fortunately, after slipping a couple of ship dates, Microsoft released Virtual Server late last year to semi-enthusiastic hand clapping from its customers.
But Microsoft never rests on one software version for too long - especially these days. Most times, the first upgrade in any Microsoft product lifecycle is called "R2" (Release 2), and so it is for Virtual Server 2005, which had its R2 release announced a couple of weeks ago. And true to form, Microsoft isn't kidding around, incorporating what it sees as the best of its competitors' features with the power it has over the OS.
For Virtual Server 2005 R2, this means changes in several areas. The two that I like best are support for native x64 hosting and, especially, PXE boot support. Being able to do a pixie boot off a central Virtual Server is a huge plus for any of us in the test lab business, and it's now going to get its own dedicated hardware in my lab.
Test lab folks will also like the fact that there's now room for guest operating systems. Unfortunately, that means only Linux. That also means only Red Hat and Suse for now - and for now really means next month, not later this month, when R2 is fully released.
You will also find higher-end upgrades, such as the ability to support the clustering of virtual machines across iSCSI and SANs. That means you can cluster two or three physical machines and run a whole bunch of hosts over that; but, far cooler, it means you can cluster a bunch of virtual machines together, whether or not they're on the same physical box.
To make this easier, Microsoft had to upgrade its virtual machine migration capabilities. If you are running a pile of servers, connected together to form a virtual hosting landscape, then that hardware must be updated, modified, and maintained over time. To keep virtual machines from going down during that time, Virtual Server now does machine migration from one host to the next at less than 10 seconds per 128MB (assuming a 1GbE iSCSI interconnect medium). Redmond picked 128MB here because the company now has documentation that shows folks how to strip down Windows XP Pro to fit into 128MB such that a few hundred VM instances of the OS won't eat up too much hardware.
Managing virtual clients
Another key feature down that alley is its capability to change virtual hard disks dynamically. Prior to R2, these disks were fixed. Now, they can grow as you load more apps on them and even alert administrators when a single disk gets too large. Redmond is still working on the capability for those same images to shrink as you remove applications.
Managing all these virtual clients has also become easier. Microsoft still has a way to go to make its console match the ease of VMware's, but it's on its way. PXE boot is a big step forward, and Redmond has also released a Virtual Server Management Pack for Microsoft Operations Manager that allows management of host and virtual machines from the same interface.
Microsoft has also upgraded its licensing scheme. By far the nastiest complaint users have had about the original version was that it was an unconscionable money-making scheme.
For developers who were trying to use Virtual Server to test hundreds of OS images, this was a nightmare because each OS image required a license, regardless of whether or not it was running.
Microsoft got sane here and dropped this to concurrent user licensing, such that you can have as many images as you want; you need active licenses only for as many instances as will be running at any one time. Hey, sanity! Take a whiff and remember it.
But wait, there's more. Redmond has also dropped the overall price of Virtual Server for the standard R2 edition and the Enterprise R2 edition. And there's still more! Every copy of Windows Server 2003 Enterprise Edition also comes with four virtual instance licenses, which means you can be running as many as four different virtual instances of W2k3 Server EE at any one time - for free. (Well, relatively speaking anyway.)
Overall, Virtual Server 2005 R2 puts this platform much closer to VMware's venerable throne at the top of the virtual machine heap. It still needs broader guest OS support, but its price point and new management tools are really starting to make the grade.