You can configure a resource of type CVMCluster in the CVM service group as shown in the sample definition. Also, review the extensive main.cf that includes the CVMCluster resource.
See Sample VCS configuration files for SF Oracle RAC.
CVMCluster cvm_clus (
Critical = 0
CVMClustName = RACCluster1
CVMNodeId = { galaxy = 0, nebula = 1 }
CVMTransport = gab
CVMTimeout = 200
)