The Skinny on Hyper-V R2 (a.k.a. Hyper-V 2.0)

April 9th, 2009 by Andy B.

At this year’s WinHEC 2008 event, Microsoft announced several new features coming in Hyper-V R2, promising to deliver the final pieces of an enterprise level OS virtualization to compete with VMware as a cloud hosting platform. New features in Windows 2008 R2, Hyper-V R2 and SCVMM 2008 include:

Live Migration

A much sought after feature in any virtualization product is live migration – the ability to move running VMs from one host to another without interruption of service. In order to achieve this, a shared file system is needed and Hyper-V R2 answers the call with a new feature called “clustered shared volumes.”

Management of live migrations is best performed under the watchful eye of System Center Virtual Machine Manager 2008, which can provide additional features such as live migration via policy. Upgrading will also be easy, you only need to update to Hyper-V R2 – no other infrastructure updates are needed.

Logical Processor Support

This new version boasts support for 32 logical processors per host, which is twice the supported number of Hyper-V 1.0.

Hot add remove storage

Add or remove virtual and pass-through disks to a running VM without requiring a reboot. (VHD and SCSI disks only – storage controllers and pass-through IDE disks cannot be hot added). This feature allows for storage growth in VMs without downtime – a major factor in achieving maximum uptime in business critical environments.

Dynamic Memory

In Hyper-V 1.0, physical memory was hard allocated to the VMs, but in 2.0 the pool of memory is dynamically allocated and removed based VM usage with no service interruption. Dynamically allocating memory to VMs can drastically improve host consolidation rates.

Hyper-V 2.0 VMs are configured with an initial RAM setting (how much the machine boots with) as well as minimum and maximum RAM values. Hyper-V then adds RAM using the Hot-Add function, and removes it using a balloon driver (for supported OSes).