Failover query in RAC
11gR2(11.2) RAC TAF Configuration for Admin and Policy Managed Databases (Doc ID 1312749.1)


  
  Create Service
  


As you have already written.


  
  Start the service
  


No TNS entry needed on the server.


  
  Make a connection. 
  
  
  The client connect string does not require any special TAF parameters.
  A simple tnsnames.ora entry as shown below will do.


mysrvb = 
  (description =
   (address = (protocol=tcp)(host=secrac-scan)(port=1521))
   (connect_data=
    (service_name=mysrvb)
   ) 
  )


Of course, use the service that was defined with TAF.