MCSA/MCSE Self-Paced Training Kit (Exam 70-284): Implementing and Managing MicrosoftВ® Exchange Server 2003 (Pro-Certification)

Network Load Balancing and the Cluster Service both increase the availability of application services but in different ways.

Network Load Balancing scales to 32 servers, and the Cluster Service scales to 8 servers.

The Cluster Service requires two network adapters: one for the public network and one for private intra-node communication.

Network Load Balancing does not require special hardware, whereas the Cluster Service requires an external shared disk resource for a multi-node cluster.

A cluster service account should be configured prior to creating the cluster and granted the Exchange Full Administrator role after installing Exchange Server 2003.

Exchange Server 2003, Enterprise Edition, is required for clustering.

Typically, front-end cluster servers use Network Load Balancing, while back-end clusters use the Cluster Service.

The recommended use of Exchange Server 2003 in a clustered environment is in an active/passive configuration.