How Clustering Actually Works

A node is a server within the cluster. Windows 2000 Advanced Server supports two-node clustering, and Windows 2000 Datacenter Server supports up to four-node clustering. Windows 2003 Enterprise Edition supports up to eight-node clustering.

As you can see in Figure 4.1, the heartbeat is a private network set up between the nodes of the cluster that checks to see whether a server is up and running. This occurs at regular intervals known as time slices. If the heartbeat is not functioning, a failover is initiated, and another node in the cluster will take over for the failed node. In addition to the heartbeat private network, at least one public network must be enabled so external connections can be made to the cluster. ...

Get Microsoft® SQL Server High Availability now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.