Understanding and Installing Hyper-V Integration Services

Hyper-V Integration Services are a set of processes that may be installed into supported guest operating systems to improve the performance and usability of that guest operating system running within a Hyper-V virtual machine. In some areas, the Hyper-V Integration Services are analogous to the VMware Tools package used to improve the interaction of guest operating systems with the VMware virtualization infrastructure. This chapter will cover guest operating systems for which Integration Services are available, provide an overview of functions performed by the services and provide details on how to install the services on a supported guest operating system.

An Overview of Hyper-V Integration Services

As previously mentioned, Hyper-V Integration Services provide a number of performance and usability enhancing features for Hyper-V based guest operating systems. These services are as follows:

• Time Synchronization Service - Synchronizes the time between the child and parent partitions. Essentially serves to avoid system time drift between the guest operating system running in a child partition and the Hyper-V parent partition.

• Heartbeat Service - The heartbeat service allows the parent partition to detect when a virtual machine has locked up or ceased to function in some other way. The parent partition sends heartbeat messages to the guest operating system in the child partition. It is then the job of the Heartbeat Service installed on the guest as part of the Integration Services to send a response to each of these messages from the parent partition. When the parent partition fails to receive responses from the child partition, it assumes the the Heartbeat Service, and therefore the guest operating system on which it running has encountered problems, and logs the event accordingly.

• Shutdown Service - Allows the guest operating system to be shut down cleanly using the Hyper-V Management interfaces, thereby avoiding the necessity to log into the guest and manually initiate the shutdown procedure. For example, when an administrator selects the Shutdown action for a virtual machine from with Hyper-V Manager, the parent partition communicates with the Shutdown Service running on the guest operating system to notify it of the request. The Shutdown Service then initiates the guest operating system's shut down process by making standard Windows Management Instrumentation (WMI) calls.

• Key/Value Pair Exchange - The purpose of the Integration Services key/value pair exchange functionality is to provide a means to set, delete, and enumerate specific information about the virtual machine and guest operating system configuration running in a child partition. In this way, the parent partition can request to set specific data values in the guest operating system, or retrieve the data to expose it to third-party management or other tools.

Key/value pair data is stored in the following guest operating system registry locations:

• HKLM\Software\Microsoft\Virtual Machine\Auto

• HKLM\Software\Microsoft\Virtual Machine\External

• HKLM\Software\Microsoft\Virtual Machine\Guest\Parameters

By default, the child partition exposes the data stored in HKLM\Software\Microsoft\Virtual Machine\Auto to the parent partition upon request. These include:

   * OSMajorVersion - The major version number of the guest operating system.
   * OSMinorVersion - The minor version number of the guest operating system.
   * OSBuildNumber - The build number of the guest operating system.
   * OSVersion – The version of the guest operating system (e.g, 5.0.2195).
   * OSPlatformId – The guest operating system platform (Win9x, NT4 or later)
   * CSDVersion – The latest Service Pack installed in the guest operating system.
   * ServicePackMajor – The major version number of the latest Service Pack installed in the guest operating system.
   * ServicePackMinor - The minor version number of the latest Service Pack installed in the guest operating system.
   * SuiteMask – The product suites available on the system.
   * ProductType – The product type installed on the system (Workstation, Server, DC)
   * OSName – The name set in HKLM\Software\Microsoft\Windows NT\CurrentVersion\ProductName.
   * ProcessorArchitecture – A processor architecture identifier (Intel, Itanium, AMD, unknown)
   * FullyQualifiedDomainName - The fully qualified DNS name that uniquely identifies the guest operating system. This name is a combination of the DNS host name and the DNS domain name. If this is a node in a cluster, then it is the fully qualified DNS name of the cluster virtual server.

The parent partition provides the values in HKLM\Software\Microsoft\Virtual Machine\Guest\Parameters to the child partition. These include:

   * HostName -The domain name system (DNS) name set in the parent partition operating system. If the system is a cluster node, then this is the DNS name of the cluster virtual server.
   * PhysicalHostName - The non-fully qualified name set in the parent partition operating system.
   * PhysicalHostNameFullyQualified - The fully qualified name set in the parent partition operating system.
   * VirtualMachineName - The name of the virtual machine used by the virtualization stack.