Hyper-V lives! Is Microsoft ready to prove it has what it takes in the virtualization arena? As I mentioned last week, Sun is on board: Read this quote from Sun's Senior Director of xVM, Vijay Sarathy. However, the company challenged Microsoft to answer some serious questions about its virtualization technology -- such as how Hyper-V can compete with the open source Xen-based alternatives and whether a Windows-only virtualization technology can hack it in today's increasingly heterogeneous datacenters.

Sun's questions are valid ones, and the answers should be of interest to anyone contemplating embracing virtualization. After all, the debate as to who offers the most reliable, most cost-effective, and most feature-rich virtualization platform is just beginning and promises a long run. I mentioned last week that I would reach out to Microsoft, as well as experts on virtualization, for some responses to Sun's queries. Would they step up to the mic?

Yes, they would.

I received responses from Patrick O'Rourke, group product manager within Microsoft's Core Infrastructure Marketing, Server and Tools Business. In addition, Greg Shields, co-founder and IT guru with Concentrated Technology weighed in. He has extensive experience in systems administration, engineering, and architecture specializing in Microsoft, virtualization, and systems management technologies.

Following are the questions posed by Sun, as well as the responses from O'Rourke and Shields.

Live migration is an important feature for customers to handle unplanned outages, as Sun and VMware have demonstrated through inclusion of live migration capabilities in their hypervisors. How will Hyper-V meet customers' migration needs without live migration?

O'Rourke: Virtualization and high availability go hand-in-hand. If you're virtualizing today without high availability, then you should reevaluate that strategy. Windows Server 2008 Enterprise and Datacenter editions provide Hyper-V and integrated failover clustering at no additional charge. In the case of unplanned downtime, VMotion can't live migrate because there is no warning. Instead you must have VMware HA configured, and the best it can do is restart the affected virtual machines on other nodes, which is the same as what is provided with Windows Server 2008 Hyper-V and integrated Failover Clustering. And nearly three weeks ago at TechEd North America, Bob Muglia announced that live migration will be in the next version of Hyper-V.

For more on this, see Microsoft senior program manager for Hyper-V Jeff Woolsey's three-part blog post, "Hyper-V Quick Migration and VMware Live Migration": part one, part two, and part three.

Shields: See this post and the resulting comments for my position on VMotion's efficacy.