Hi All,

System Center Virtual Machine Manager 2008 (VMM) is a comprehensive management solution for the virtualized data center, enabling increased physical server utilization, centralized management of virtual machine infrastructure, and rapid provisioning of new virtual machines by the administrator, delegated administrator, and authorized end users. VMM 2008 can manage hosts that are running Windows Server 2008 with Hyper-V, Virtual Server 2005 R2, and VMware ESX through VirtualCenter Server.

Recently, Windows Server 2008 released an R2 Beta version that included significant feature improvements to Hyper-V. To leverage these new platform enhancements and extend the feature set of VMM 2008, a corresponding Beta version of VMM 2008 R2 has been released. This topic provides an overview of the following significant new features that are included in VMM 2008 R2 Beta:

  • Windows Server 2008 R2 Beta Hyper-V host management
  • Enhanced support for shared storage and SAN transfers, including support for multiple virtual machines per logical unit number (LUN) by using clustered shared volumes.
  • Maintenance mode for hosts

More info in these posts from the team here and here.

Windows Server 2008 R2 Beta Hyper-V Host Management

With VMM 2008 R2 Beta, you can create and manage virtual machines running on Windows Server 2008 R2 Beta Hyper-V hosts. When you add a host that is running Windows Server 2008 R2 Beta and does not have Hyper-V enabled, VMM 2008 R2 Beta automatically enables the Hyper-V role on the host.

VMM 2008 R2 Beta supports the following new Windows Server 2008 R2 Beta features:

  • Live migration between Windows Server 2008 R2 Beta Hyper-V clustered hosts. With live migration, you can migrate a virtual machine from one node of a Windows Server 2008 failover cluster to another node in the same cluster. Because the virtual machine does not experience any downtime, the move is completely transparent to the users that are connected to the virtual machine.
  • Network optimization detection during virtual machine placement. VMM 2008 R2 Beta supports both Virtual Machine Queue (VMQ) and TCP Chimney, which are Windows Server 2008 R2 Beta features that improve network performance for virtual machines.
  • Network adapters that support the VMQ feature are able to create a unique network queue for each virtual network adapter and then connect that queue directly to the virtual machine’s memory. This connection routes packets directly from the hypervisor to the virtual machine, bypassing much of the processing in the virtualization stack.
  • Network adapters that support the TCP Chimney feature are able to offload the processing of network traffic from the networking stack. Both of these features increase network performance and reduce CPU utilization.
  • Hot addition and removal of virtual hard disks (VHDs). In Windows Server 2008 R2 Beta, Hyper-V allows users to add and remove VHDs from a virtual machine while it is running.

Enhanced Support for Shared Storage and SAN Transfers

VMM 2008 R2 Beta provides the following enhancements:

Clustered Shared Volume (CSV) Support

VMM 2008 R2 Beta supports the Windows Server 2008 R2 Beta clustered shared volume (CSV) feature. CSV enables all hosts on a Windows Server 2008 R2 Beta failover cluster to concurrently access virtual machine files on a single shared logical unit number (LUN). Because all nodes on the cluster can access a single shared LUN, virtual machines have complete transparency with respect to which nodes actually own a LUN. This enables live migration of virtual machines within the cluster because all nodes in the cluster can access any LUN.

SAN Migration into and out of Clustered Hosts

VMM 2008 R2 Beta supports the use of SAN transfers to migrate virtual machines and highly available virtual machines into and out of a cluster. When you migrate a virtual machine into a cluster by using a SAN transfer, VMM checks all nodes in the cluster to ensure that each node can see the LUN and automatically creates a cluster disk resource for the LUN. Even though VMM automatically configures the cluster disk resource, it does not validate it. You must use the Validate a Configuration Wizard in Failover Cluster Management to validate the newly created cluster disk resource. To migrate a virtual machine out of a cluster, the virtual machine must be on a dedicated LUN that is not using CSV.

Expanded Support for iSCSI SANs

VMM 2008 supports SAN transfers of virtual machines that use initiator-based iSCSI target connection, which allows only one LUN per iSCSI target. VMM 2008 R2 Beta adds support for masking-based target connections, which allows multiple LUNs per iSCSI target and expands VMM support for iSCSI SAN providers.

Maintenance Mode for Hosts

In VMM 2008 R2 Beta, you can start maintenance mode for a Windows-based host anytime you need to perform maintenance tasks on the host, such as applying updates or replacing a physical component.

When you start maintenance mode on a host in a Windows Server 2008 R2 Beta cluster with highly available virtual machines, you can do one of the following:

  • If the option is available, use live migration to evacuate all virtual machines to other hosts on the same cluster. If the migration fails for any virtual machine on the host, maintenance mode is not started on that host and VMM does not migrate back the virtual machines that have already migrated.
  • Place all virtual machines on the host into a saved state.

When you start maintenance mode on a stand-alone Windows-based host, a host within a Windows Server 2008 R2 Beta cluster, and any non-highly available virtual machines on a Windows Server 2008 R2 Beta host, VMM automatically places all virtual machines into a saved state.


When VMM places virtual machines into a saved state, any users of the virtual machines will experience a loss of service.

When you start maintenance mode on any host, VMM automatically does the following:

  • Blocks virtual machine creation operations on the host.
  • Excludes the host from the host ratings during placement.
  • Displays a host status of In Maintenance Mode in Host view of the VMM Administrator Console.

When you stop maintenance mode on a host, VMM allows virtual machine creation operations on the host, includes the host in the host ratings during placement, and displays a host status of OK in Host view of the VMM Administrator Console. However, VMM does not automatically do a live migration to move highly available virtual machines back onto the host in a Windows Server 2008 R2 cluster, and it does not restart any of the virtual machines on the host.

To start or stop maintenance mode, in Host view of the VMM Administrator Console, right-click a host, and then click the appropriate command.

Sign Up here!

The beta is a public download, available now - full software install or the pre-configured VHD from https://connect.microsoft.com/site/sitehome.aspx?SiteID=799 please sign in with your Windows Live ID

The pre-configured virtual hard disk (VHD) is a virtual machine with a pre-installed evaluation version of Virtual Machine Manager (VMM) 2008 R2 Beta that you can use to evaluate the product's features.  If you don't already have access to VMM on the Connect site you can get to it here by simply filling out a quick survey, which will help us better understand your virtualization needs.