Multi data sources provide failover and load balancing for connection
      requests between two or more data sources. Before you create a multi
      data source, you should create the data sources that the multi data
      source will manage, and deploy them to same targets that you want to
      deploy the multi data source to. Note that the underlying databases must
      have some kind of data synchronization or replication. WebLogic Server
      does not handle that replication.
      The main steps for
      configuring JDBC multi data sources are: