A grid link data source uses fast connection failover to:
Provide rapid failure detection.
Abort and remove invalid connections from the connection pool.
Perform graceful shutdown for planned and unplanned Oracle RAC node outages. The data source allows in-progress transactions to complete before closing connections. New requests are load balanced to an active Oracle RAC node.
Adapt to changes in topology, such as adding a new node.
Distribute runtime work requests to all active Oracle RAC instances.
Refer to “Fast Connection Failover” in the Oracle Database JDBC Developer's Guide and Reference at: http://docs.oracle.com/cd/B19306_01/java.102/b14355/fstconfo.htm.