If you are using Oracle 10g, no Oracle RAC server resources are required. For more information, see Creating Resources for Interoperation With Oracle 10g by Using Sun Cluster Maintenance Commands.
You require one scalable resource group for each Oracle RAC database. Each resource group contains the Oracle RAC server resource that represents all instances of the database in the cluster. Ensure that this scalable resource group is mastered on all nodes where Oracle RAC is to run.