Virtual migration enhancements: In Windows 8 Server, you don't have to have a clustered Hyper-V configuration to migrate among servers, called share-nothing live migration. Today's Hyper-V lets you move a virtual machine only from one server to another if they are on the same CSV (clustered shared volume). But the version in Windows 8 Server lets you move a virtual machine from one server to another without using shared storage; instead, you can use the local storage of each system, so essentially Hyper-V doesn't require a SAN, but virtual machines can be stored on file servers. Keep in mind that this isn't a replacement for high-availability options with live migration -- this capability is intended for use in planned moves, not failovers. (Note that VMware has a product that does the same thing: the extra-cost vSphere Storage Appliance.)
Multiple concurrent live migration: In Windows Server 2008 R2, Hyper-V could perform just a live migration, which only allowed for a single migration move at a time. By contrast, vSphere could perform simultaneous moves. But in Windows 8 Server, there is apparently no limit to the number of concurrent migrations you can perform in Hyper-V.
Performance improvements: These include a new Hyper-V ODX (offload data transfer) engine that will help reduce the CPU usage during data transfers if the back-end shared storage subsystem supports ODX. It allows the copying processing power to be handled by the storage, so the CPU is not involved as much on the virtual system. Windows 8 Server's Hyper-V also can map a virtual machine to specific CPU cores to ensure dedicated resources are always available for that virtual machine.
Virtual machine copy recovery: The Hyper-V Replica feature allows you to have a copy of the virtual machines sitting on another system so that if the first one dies you can bring the copy up and be good to go. This is great for server failover, but it also works for complete site failover without breaking the bank. (Note that VMware has a similar capability called vSphere Replication in its extra-cost vCenter Site Recovery Manager.)
Windows 8 Server's Hyper-V sounds very compelling, doesn't it? Of course, I need to remember that Windows 8 Server is still in the pre-beta "developer preview" phase, with a public release not slated until late 2012, so nothing is definitive. Still, it's obvious that Microsoft is doing everything it can to make up ground in the competition with VMware. For its part, VMware hasn't stopped creating and tweaking its products, either, so you can expect VMware will have some new features to boast about as the Windows 8 Server release nears.
Still, my money has been and continues to be on Microsoft Hyper-V. I use it daily, have seen it grow over the past few years, and have confidence that Version 3 in Windows 8 Server will see an even greater fan base as even VMware apostles start to appreciate its lower cost and expanded functionality.
This article, "Why Hyper-V in Windows 8 Server could finally beat VMware," was originally published at InfoWorld.com. Read more of J. Peter Bruzzese's Enterprise Windows blog and follow the latest developments in Windows at InfoWorld.com. For the latest business technology news, follow InfoWorld.com on Twitter.