Multiplex Control Files In 11gR2 RAC/ASM.

1) Add location to the control_files parameter.

[oracle@rac1 ~]$ export ORACLE_SID=orcl1
[oracle@rac1 ~]$ sqlplus / as sysdba

SQL*Plus: Release 11.2.0.1.0 Production on Sun Aug 18 11:22:46 2013

Copyright (c) 1982, 2009, Oracle.  All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.2.0.1.0 - Production
With the Partitioning, Real Application Clusters, Automatic Storage Management,                                                    OLAP,
Data Mining and Real Application Testing options

SQL> show parameter control_files;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
control_files                        string      +DATA/orcl/controlfile/current
                                                 .260.823159575, +FRA/orcl/cont
                                                 rolfile/current.256.823159577




SQL> alter system set control_files='+DATA/orcl/controlfile/current.260.823159575', 
'+FRA/orcl/controlfile/current.256.823159577', '+DATA', '+FRA' scope=spfile;

2) Stop the database and start it in nomount mode.

[oracle@rac1 ~]$ srvctl stop database -d orcl
[oracle@rac1 ~]$ srvctl start database -d orcl -o nomount


3) Create the control file using RMAN by pointing to an actual existing controlfile.

[oracle@rac1 ~]$ rman target /

Recovery Manager: Release 11.2.0.1.0 - Production on Sun Aug 18 11:38:56 2013

Copyright (c) 1982, 2009, Oracle and/or its affiliates.  All rights reserved.

connected to target database: ORCL (not mounted)


RMAN> restore controlfile from '+DATA/orcl/controlfile/current.260.823159575';

Starting restore at 18-AUG-2013 11:39:31
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=1 instance=orcl1 device type=DISK

channel ORA_DISK_1: copied control file copy
output file name=+DATA/orcl/controlfile/current.260.823159575
output file name=+FRA/orcl/controlfile/current.256.823159577
output file name=+DATA/orcl/controlfile/current.270.823779575
Finished restore at 18-AUG-2013 11:39:39

4) Stop the database and start it in normal mode.

[oracle@rac1 ~]$ srvctl stop database -d orcl
[oracle@rac1 ~]$ srvctl start database -d orcl


SQL> select open_mode,name from v$database;

OPEN_MODE            NAME
-------------------- ---------
READ WRITE           ORCL


+DATA/orcl/controlfile/current.260.823159575
+FRA/orcl/controlfile/current.256.823159577
+DATA/orcl/controlfile/current.269.823780197
+FRA/orcl/controlfile/current.271.823780199