For more information about setting up a Disaster Recovery environment, see these documents:
The Oracle Fusion Middleware Disaster Recovery Guide (http://download.oracle.com/docs/cd/E14571_01/doc.1111/e15250/intro.htm#BABHCEJJ)
The Oracle Data Guard documentation at http://www.oracle.com/technology/deploy/availability/htdocs/DataGuardOverview.html
Oracle Fusion Middleware DR Solution Using NetApp Storage at http://www.netapp.com/us/library/technical-reports/tr-3672.html
The Disaster Recovery guide for the RDBMS that you use.