From RAC to Standby RAC With Active Dataguard

I have oracle database 11.2.0.3 with RAC feature , with 2 node on oracle linux 6.4 : ol6-112-rac1 and ol6-112-rac2 I want to create active data guard with RAC feature from this database , these active dataguard with rac option has 2 node : ol6-rac1-guard,ol6-rac2-guard I want to use this document for creation active data guard from rac database to rac database : http://www.oracledba.org/11gR2/dr/11gR2_dataguard_RAC_to_RAC.html#Create_Physical_Standby I do the steps in this document , all of things is ok but in step " Start the Managed Recovery Process " after i want to switch log in primary , switch log is not occurred on standby database . After " tail of alert log " on standby database and executing " Switch log " on primary , this error is occurred : tail -f /ora01/app/oracle/diag/rdbms/racguard/racguard1/trace/alert_racguard1.log Wed Feb 17 04:37:57 2016 Media Recovery Waiting for thread 1 sequence 76 Error 12154 received logging on to the standby FAL[client, USER]: Error 12154 connecting to rac for fetching gap sequence This is my mistake , can any one help me ?