What’s New in VMM 2008 R2

Live Migration: Seen through the VMM console, this enables administrators to move a virtual machine between clustered hosts in a way that is completely transparent to the users connected to the virtual machine. This allows administrators greater flexibility in responding to planned downtime and provides higher machine availability. The basic requirements for Live Migration are that all hosts must be part of a Windows Server 2008 R2 failover cluster and host processors must be from the same manufacturer. Additionally all hosts in the cluster must have access to shared storage. No changes are required to existing virtual machines, network, or storage devices in moving from Quick Migration to Live Migration other than upgrading to  Windows Server 2008 R2 and VMM 2008 R2.

Hot addition/removal of Storage: Allows the addition and removal of storage to virtualized infrastructure without interruption. Additionally, "live” management of virtual hard disk (VHDs) or iSCSI pass through disks, allows administrators to take advantage of additional backup scenarios and readily use mission critical and storage-intensive applications.

New optimized networking technologies: VMM 2008 R2 supports two new networking technologies – Virtual Machine Queue (VMQ) and TCP Chimney – providing increased network performance while creating less of a CPU burden. NICs that support VMQ, create a unique virtual network queue for each virtual machine on a host that can pass network packets directly from the hypervisor to the virtual machine. This increases throughput as it bypasses much of the processing normally required by the virtualization stack. With TCP Chimney, TCP/IP traffic can be offloaded to a physical NIC on the host computer reducing CPU load and improving network performance.

Clustered Shared Volumes (CSV): Provides a single, consistent storage space that allows hosts in a cluster to concurrently access virtual machine files on a single shared logical unit number (LUN). CSV eliminates the previous one virtual machine per LUN restriction and coordinates the use of storage with much greater efficiency and higher performance. CSV enables the Live Migration of virtual machines without impacting other virtual machines sharing the same LUN. Enabling CSV on failover clusters is straightforward; many storage configuration complexities prior to CSV have now been eliminated.

SAN migration into and out of clustered hosts: This allows virtual machines to migrate into and out of clusters using a SAN transfer, which saves the time required for copying the virtual machine file over the network.

Expanded Support for iSCSI SANs: Previously, only one LUN could be bound to a single iSCSI target whereas now – with support now built into VMM 2008 R2 – multiple LUNS can be mapped to a single iSCSI target. This provides broader industry support for iSCSI SANs allowing customers more flexibility in choosing storage providers and iSCSI SAN options.

Storage Migration: Quick Storage Migration enables migration of a VM’s storage both within the same host and across hosts while the VM is running with a minimum of downtime, typically less than 2 minutes. VMM 2008 R2 also supports VMware storage vMotion which allows the storage of a VMware VM to be transferred while the VM remains on the same host with no downtime.

Rapid Provisioning:  Allows administrators to take advantage of SAN provider technologies to clone a LUN containing a VHD and present it to the host while still utilizing the VMM template so the OS customization and IC installation can be applied.

Support for third party CFS: For users requiring a true clustered file system, VMM 2008 R2 supports third party file systems by detecting CFS disks and allows for deploying multiple VMs per LUN.

Support for Veritas Volume Manager VMM 2008 R2 recognizes Veritas Volume Manager disks as a cluster disk resource.

Maintenance Mode: Allows administrators to apply updates or perform maintenance on a host server by safely evacuating all virtual machines to other hosts on a cluster. Maintenance mode can be configured to use Live Migration to move the virtual machines or can put the workloads into a saved state to be safely reactivated when maintenance or upgrades are complete. Maintenance mode is enabled for all supported hypervisor platforms on Windows Server 2008 R2.

Support of disjoint domains: Reduces the complexity of reconciling host servers with differing domain names in Active Directory and DNS. In these situations, VMM 2008 R2 automatically creates a custom service principal name (SPN) configured in both AD and DNS allowing for successful authentication.

Use of defined port groups with VMware Virtual Center: On installation, VMM 2008 R2 will present available port groups for VMM’s use with VMware vCenter thus allowing administrators to maintain control over which port groups are used.

Queuing of Live migrations:  This feature enables users to do multiple Live Migrations without needing to keep track of other Live Migrations that are happening within the cluster. Detects when a Live Migration will fail due to another Live Migration already in progress and queues the request for later.

Host compatibility checks: VM migration requires host hardware to be compatible; this feature provides a deep check for compatibility using Hyper-V and VMware compatibility check APIs. Administrators can check if the source host is compatible with the destination host before performing a migration and finding out the VM cannot start on the new host.  A related feature makes a VM compatible by turning off certain CPU features which makes the VM compatible with the hosts in the cluster.