The Microsoft Exchange Server version 5.5 Enterprise Edition includes many enhancements that provide support for Microsoft Cluster Server version 1.0. Clustering your Microsoft Exchange Server computers ensures that messaging services remain uninterrupted even if one of the clustered servers fails. For example, if the processor in a clustered Microsoft Exchange Server computer fails, another server in the cluster is available in its place. Users on the failed server do not see a change in their e-mail service. They can continue to send and receive mail, and browse public folders as usual.
Note Clustering is supported only in the Microsoft Exchange Server Enterprise Edition.
Clustering is also convenient if you need to update a server or add new hardware without interrupting service to users. Services can fail over to another server in the cluster so the other server takes over the functions of the server you are upgrading.
This section describes procedures for planning, installing, and administering Microsoft Exchange Server in a cluster environment. It assumes that you are familiar with Microsoft Cluster Server operations and concepts. For more information about clustering, see your Microsoft Cluster Server documentation.
The following Microsoft Exchange Server components are not supported in a cluster environment:
Note For more information about using the Microsoft Exchange Server X.400 Connector using TCP/IP in a cluster environment, see the Microsoft Knowledge Base article Q169113: "Using an X.400 Connector with the Transmission Control Protocol/Internet Protocol (TCP/IP) in a Cluster Environment," at the Microsoft Technical Support Web site (http://www.microsoft.com/support).