The figure shows how data sources and multi data sources connect three WebLogic server groups with three Oracle RAC instances.
Each group connects to one multi data source. Each multi data source connects to three data sources.
One data source under multi data source A connects to RAC 1 as a primary database and the other two data sources connect to RAC 2 and RAC 3 as backup databases. One data source under multi data source B connects to RAC 2 as a primary database and the other two data sources connect to RAC 1 and RAC 3 as backup databases. One data source under multi data source C connects to RAC 3 as a primary database and the other two data sources connect to RAC 2 and RAC 1 as backup databases.
The new data sources are those connecting multi data source A and B and C to RAC 3, and those connecting multi data source C to RAC 1 and RAC 2.