Hyper-V Features

Now that we’ve gone over both the scenarios and architecture of Hyper-V, let’s dive into some of the features of Microsoft’s virtualization platform:

32-bit (x86) and 64-bit (x64) VMs Hyper-V provides support for both 32-bit as well as 64-bit VMs. This lets users provision both architectures on the same platform, easing the transition to 64-bit and providing legacy 32-bit operating systems.

Large memory support (64 GB) within VMs With support for up to 64 GB of RAM, Hyper-V scales out to run the vast majority of enterprise-class workloads. Hyper-V can also use up to a total of 1 terabyte (TB) of RAM on the host.

SMP virtual machines Symmetric Multi Processor (SMP) support allows VMs to recognize and utilize four virtual processors. As a result, server applications running in a Hyper-V VM take full advantage of the host system’s processing power.

Integrated cluster support for quick migration and high availability (HA) Windows Server 2008 Hyper-V and HA go hand in hand. It’s easy to create a failover cluster of VM hosts that your VMs can live on. After you set up the failover cluster, you can quickly and easily move a VM from one host to the other from the Failover Cluster Manager or from other management tools (such as System Center Virtual Machine Manager).

Volume Shadow Service integration for data protection Hyper-V includes a Volume Shadow Services (VSS) provider. As we discussed earlier, in the list of scenarios, VSS lets backup applications prepare the system for a backup without requiring the applications (or VMs) to be shut down.

Pass-through high-performance disk access for VMs When a physical volume is connected directly to the VM, disk I/O–intensive workloads can perform at their peak. If the Windows Server 2008 system can see the volume in the Disk Management control panel, the volume can be passed through to the VM. Although you’ll see faster performance with pass-through disk access, certain features (such as snapshots, differencing disks, and host-side backup) that you get from using a VHD file aren’t available with pass-through disks.

VM snapshots Snapshots let administrators capture a point in time for the VM (including state, data, and configuration). You can then roll back to that snapshot at a later point in time or split from that snapshot to go down a different path. The snapshot is a key feature for the test and development scenario, because it lets users easily maintain separate points in time. For example, a user may install an operating system inside a VM and take a snapshot. The user can perform a number of tasks and then take a second snapshot. Then, the user can return to either of those snapshots later, saving configuration time and effort.

New hardware-sharing architecture (VSP/VSC/VMBus) By using the new VMBus communication protocol for all virtual devices, Hyper-V can provide higher levels of performance than were previously seen with Microsoft virtualization products.

Robust networking: VLANs and NLB Virtual Local Area Network (VLAN) tagging—also referred to as the IEEE standard 802.1q—provides a secure method for multiple networks to use the same physical media. Hyper-V supports VLAN tagging (802.1q) on the virtual network interfaces and specifies a VLAN tag for the network interface. Network Load Balancing (NLB) support in Hyper-V allows VMs to participate in an NLB cluster. An NLB cluster is different from a failover cluster, such as those used for VM quick migration. NLB clusters are configured with front-end nodes that handle all incoming traffic and route it to multiple servers on the back-end.

DMTF standard for WMI management interface The Distributed Management Task Force (DMTF) is a standards body that provides a uniform set of standards for the management of IT environments. Microsoft has worked closely with the DMTF to ensure that all the management interfaces for Hyper-V adhere to the standards, allowing management tools from multiple vendors to manage the system.

Support for full or Server Core installations Hyper-V can run on a full installation of Windows Server 2008 as well as the Server Core option. We’ll discuss Server Core in more depth later.


Advantages over Virtual Server
Windows Server 2008 Hyper-V has a number of advantages over Virtual Server 2005 R2 SP1:

• Support for SMP and 64-bit VMs. Virtual Server was limited to 32-bit uni-processor virtual machines.
• Support for more than 3.6 GB of RAM per VM.
• Support for mapping a logical unit number (LUN) directly to a VM.
• Increased performance from VSP/VSC architecture.
• Hyper-V management via a MMC-based interface instead of the web-based console.

However, it’s impossible for users who have only 32-bit hardware in their environment to move to Hyper-V (because it’s a feature of the 64-bit version of Windows Server 2008).

Source of Information : Sybex Windows Server 2008 Hyper-V Insiders Guide to Microsofts Hypervisor