Support for server clustering between Windows Server 2003 and Virtual Server 2005 R2

This article discusses the support for server clustering between Microsoft Windows Server 2003 and Microsoft Virtual Server 2005 R2. Additionally, this article discusses a guest cluster deployment scenario and a host cluster deployment scenario.

Server clustering and Virtual Server 2005 R2

You can combine the Windows Server 2003 server cluster feature with the Virtual Server 2005 R2 product to create virtualized failover cluster environments for high availability. Virtual Server 2005 R2 is supported in either a “host cluster” configuration or in a “guest cluster” configuration. The following list describes the terminology that is used in this article:

• Guest
  This is an operating system instance that is running in a virtual machine.
• Host
  This is an operating system on which the Virtual Server 2005 R2 application runs. This generally represents a physical computer.
• Guest clustering
  This is a cluster where member nodes are guests in a virtual machine.
• Host clustering
  This is a cluster where member nodes are physical hosts.

Guest cluster

In this configuration, the virtual machines are nodes of a cluster. Applications are clustered for high availability within the guest operating system. These applications run on the cluster failover from guest to guest. The virtual machines do not relocate to different hosts in this configuration. The following list describes the requirements and the settings for the guest cluster configuration:

• Only guest-to-guest clustering is supported. That means this configuration cannot have a cluster that consist of a physical node and node running in a virtual machine.
• The host must be running Windows Server 2003.
• All guest computers must be running Windows Server 2003 with Service Pack 1 (SP1), Enterprise Edition, Windows Server 2003 with SP1, Datacenter Edition, or a later version.
• The Windows Server Catalog must qualify and must list host hardware as a complete iSCSI cluster solution.
• You must be using Virtual Server 2005 R2 or a later version.
• Microsoft iSCSI Software Initiator 2.0 or a later version must be installed on the guest cluster.
• If hosts have nodes that are running in a virtual machine, the hosts cannot be clustered.
• Each guest cluster requires three emulated NICs. These NICs are public, private, and iSCSI SAN.
• Nodes that are running in a virtual machine of the same cluster may reside on the same hosts or on different hosts.
• Multiple virtual machine nodes from different clusters may reside on the same host.
• The virtual machine configuration and the data files such as .vhd and .vmc must reside on the local hard disks of the hosts. The virtual machine configuration and the data files do not fail over.

Host cluster

In this configuration, the Virtual Server 2005 R2 application is clustered similarly to any other clustered application on a typical server cluster. The virtual machines become units of failover that can be moved from node to node in the cluster. The following list describes the requirements and the settings for the host cluster configuration:

• The host cluster must be running Windows Server 2003, Enterprise Edition or Windows Server 2003, Datacenter Edition.
• Hosts are standard nodes in a cluster.
• The Windows Server Catalog must qualify and must list the complete cluster solution the same as any other cluster.
• Any storage media type such as parallel SCSI, fiber channel, iSCSI, or SAS may be used for shared storage.
• The guest cluster can run any operating system.
• The virtual machine configuration and the data files such as .vhd and .vmc reside on the shared hard disks in the cluster.

For more information about how to create a host cluster, visit the following Microsoft Web site:For more information about iSCSI support for a Microsoft Windows Server 2003 failover cluster, visit the following Microsoft Web site: For more information about policy for using other virtualization software, click the following article number to view the article in the Microsoft Knowledge Base: