You’ll want to read Isaac’s blog post about the RC milestone of Windows Server 2008 R2. His post focuses on 64 LP support and processor compatibility mode for live migration. Read the post here.

Here’s an excerpt:

64LP Support

We have seen processors grow from 1, 2, 4, and now 6 cores on a single processor, soon to hit 8.  Within the Windows Server 2008 R2 lifecycle, 64 logical processor servers will become commonplace (8 processors x 8 cores).  Virtualization is the natural fit for these next-gen servers, allowing them to consolidate a greater number of virtual machines on a single host. Hyper-V is in line with these hardware trends all with an eye towards bringing you greater VM density. The dev team has done a fantastic job in building and testing a platform that can scale.

Let’s take a quick look at the history of logical processor support for Hyper-V:

• Server 2008 Hyper-V                                         16 LP Support
• Server 2008 Hyper-V +update (KB95670)      24 LP Support
• Server 2008 R2 Hyper-V Original POR           32 LP Support
• Server 2008 R2 Hyper-V RC/RTM                   64 LP Support!

Processor Compatibility Mode for Live Migration 

Live Migration is the killer-feature in Windows Server 2008 R2!  Previous to the RC build of Windows Server 2008 R2, identical CPUs were needed across every node in the cluster in order to perform a live migration.  As we came closer to the RC milestone we got feedback from customers and partners asking, "What if I deploy additional nodes that contain newer processors with features not contained in the original nodes?"  Well, we’ve solved that problem due to tremendous effort by the Hyper-V development team.

Processor compatibility mode is very straightforward. It enables live migration across different CPU versions within the same processor family (i.e. Intel-to-Intel and AMD-to-AMD). However, it does NOT enable cross platform from Intel to AMD or vice versa. It works by abstracting the VM down to the lowest common denominator, in terms of instruction sets, which enables live migrations across a broader range of Hyper-V host hardware.

There are a few things to note: Processor compatibility mode is disabled by default but you can configure it on a per-VM basis. There are no specific hardware requirements other than the CPUs must support hardware assisted virtualization (i.e. Intel’s IVT and AMD’s AMD-V).

 

From http://blogs.technet.com/virtualization/archive/2009/05/12/hyper-v-in-ws08-r2-release-candidate-bringing-more-to-the-table.aspx

Alessandro

 

Hi Guys

In addition to all the new capabilities R2 Beta introduced here’s what is new in SCVMM 2008 R2 Release Candidate:

Storage Migration:
Enables migration of storage for a running VM. This is especially relevant as customers upgrade to Windows 2008 R2 as it allows them to easily migrate away from their existing one VM per LUN deployments and consolidate their VMs into a single CSV. For Hyper-V, this feature enables migration of a running VM?s storage both within the same host and across hosts with minimum downtime. For VMWare, this feature enables storage vMotion.

Rapid VM Provisioning:
Enables rapid creation of VMs without the need to copy VHDs over the network. Customers can now use storage technologies such as snap cloning to clone VHDs and then use the rapid provisioning feature to create VMs while continuing to take advantage of the VMM features to do OS customization and IC installation.

Host compatibility checks:
Enables checks for CPU features and enlightenment parity to ensure compatibility between a VM and a host prior to migration. A related feature to make a VM compatible with a host by limiting the use of certain CPU features is also enabled.

Queuing of Live migrations:
Enables users to do multiple live migrations within a cluster. VMM now detects the condition where live migrations fail due to collisions with in-progress live migrations and automatically performs queuing and retries in the background.

Support for 3rd party CFS:
Enables support for clustered file systems from ISVs that implement functionally similar to CSV (Clustered shared volumes). This feature allows for backwards support for CSV scenarios on Windows 2008.

Support for Custom Disk resource:
Enables support for Veritas volume manager by recognizing Veritas volume manager disks as a cluster disk resources.

To get assistance with the RC please participate in our public forums: http://social.technet.microsoft.com/Forums/en-US/category/virtualmachinemanager