Using Microsoft Cluster Server to create a virtual server (257932)

SUMMARY

With the Microsoft Cluster service (MSCS) you have the ability to bind multiple NetBIOS network names to one physical server. To do this, you can create a Network Name resource in Cluster Administrator, and then you can set a dependency on an IP Address resource. The Network Name resource creates a virtual server to which users connect.

To access a network application, or resource in a non-clustered environment, network clients must connect to a physical server (that is a specific computer on the network that is identified by a unique network name, and IP address). If that server fails, access to the application, or resource is lost.

Through server clusters, MSCS enables the creation of virtual servers. Unlike a physical server, a virtual server is not associated with a specific computer, and it can failover from one node to another like a group. It can also be made available, or taken offline dynamically without affecting other virtual servers, and resources that the server is making available. If the node that is hosting the virtual server fails, clients can still access its resources by using the same server name, but they will be redirected to a different node in the Cluster.

Although MSCS is designed to allow a system administrator to connect multiple servers in a high-availability Cluster, you can also use it on a single server to provide multiple "virtual servers" within one physical server, with minimal configuration required. This is referred to as a "Lonewolf," or single-node Server Cluster, in which each virtual server has its own name, and unique IP address associated with it. This can be useful in server consolidation, and in taking advantage of the enhanced features of clustering, such as dynamic-file shares for home directory shares.

For additional information about their limitations, click the following article number to view the article in the Microsoft Knowledge Base:

235529 Kerberos Support on Windows 2000-Based Server Clusters

MORE INFORMATION

To set up a virtual server, follow these steps:

Start Cluster Administrator (CluAdmin.exe), right-click it, and then click Configure Application.
Select the Create a new virtual server check box.
Select the Create a new resource group check box, or use an existing group.
Name the group for use within Cluster Administrator.
Enter the network name, which needs to be a unique NetBIOS name on the network. Do not use the same name for more then one resource on the same Cluster. The clients will use this name to connect to resources. It is important to not use the cluster name for client connections because it does not bind to the LAN Manager stack in the same way. For client connections, create new, independent virtual servers, such as:
\\%VirtualServer%\%ShareName%
In addition, enter in an IP address on which the network name is to be dependent. This is the IP address that will be associated with this network name in Windows Internet Naming Service (WINS), and dynamic Domain Name System (DDNS) registrations, and to which the users will connect.

NOTE: A Network Name resource should be dependent on only one IP Address resource, or else connectivity issues can occur.
Select No, I'll create a cluster resource for my application later, and then finish the Configure the Application wizard.
Right-click the newly created group, and then select Bring Online.
Test connectivity to the newly created Virtual Server:
1. Click Start, click Run, and then type \\%VirtualServer%. Verify that you can see the available resources.
  
  NOTE: Because there is only one LAN Manager stack on a particular server, you will be able to browse all resources that other virtual servers are publishing, and that are owned by that same node.For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
  170762 Cluster Shares Appear in Browse List under Other Names
2. Try to connect to the virtual server name from a remote location, and verify that the returned IP address is the desired one on which the resource is dependent.
3. Fail the group over to another node in the cluster, verify that it comes online, and verify all of the previous steps as well.
4. In addition, execute all of the above steps from a client on a remote network.
  
  NOTE: When a failover of a virtual server occurs, clients connect to the same network name, and IP address, but the media access control (MAC) address that is associated with the IP address now changes.For additional information, click the article number below to view the article in the Microsoft Knowledge Base:
  244331 MAC Address Changes for Virtual Server During a Failover