Clustering SQL Server
BizTalk Server relies heavily on SQL Server for data persistence. To provide high availability for the BizTalk Server databases, create a server cluster by using Windows Server Clustering to configure two database computers that are running SQL Server. This server clustering provides redundancy and fault tolerance for the BizTalk Server databases. Unlike load-balanced clustering, where a group of computers function together to increase availability and scalability, server clustering typically involves a pair of database computers in an active/passive configuration so that one computer provides backup resources for the other.
The following figure shows a BizTalk Server database tier with high availability through active/passive server clustering.
If the active database computer encounters errors or fails, the passive computer becomes active and assumes control over the database resources until the failed computer is repaired. The database service fails over and restores data connections to the new active computer and enables the BizTalk application to continue functioning.
For information about clustering SQL Server, see your SQL Server documentation.