1. Identify the location of the current controlfile:

SQL> select name from v$controlfile;

NAME
--------------------------------------------------------------------------------
/u01/control01.ctl'

2. Shutdown the database and start the instance:

SQL> shutdown normal
SQL> startup nomount

3. Use RMAN to move the controlfile to ASM :

$ rman nocatalog
RMAN>connect target
RMAN>restore controlfile to '<DISKGROUP_NAME>' from '<OLD_PATH>';
e.g.
RMAN> restore controlfile to '+DG1' from '/u01/control01.ctl';

4. On the ASM instance, identify the name of the controlfile using ASMCMD:

$asmcmd
ASMCMD> find -t CONTROLFILE +DG1 *

Find

Purpose:
Displays the absolute paths of all occurrences of the specified name (with wildcards) in a specified directory and its subdirectories.


Syntax and Description:
find [-t type] dir name


This command searches the specified directory and all subdirectories below it in the directory tree for the supplied name. name can be a directory name or a filename, and can include wildcard characters. dir may also include wildcards. In the output of the command, directory names are suffixed with the slash character (/) to distinguish them from filenames.

You use the -t flag to find all the files of a particular type (specified as type). For example, you can search for control files by specifying type as CONTROLFILE. Valid values for type are the following:

CONTROLFILE
DATAFILE
ONLINELOG
ARCHIVELOG
TEMPFILE
BACKUPSET
DATAFILE
PARAMETERFILE
DATAGUARDCONFIG
FLASHBACK
CHANGETRACKING
DUMPSET
AUTOBACKUP
XTRANSPORT

Note:
These are the values from the type column of the V$ASM_FILE view.

Changing the current directory to the diskgroup where the controlfile was created will speed the search.

Output:
ASMCMD> find -t CONTROLFILE +DG1 *
+DG1/ORCL/CONTROLFILE/current.261.639419131
ASMCMD>

Note the name assigned to the controlfile.

5. On the database Instance:

* Modify init.ora or spfile, replacing the new path to the init parameter control_files.
* if using init<SID>.ora, just modify the control_files parameter and restart the database.
* If using spfile,

1]SQL>startup nomount the database instance
2]SQL>alter system set control_files='+DG1/ORCL/CONTROLFILE/current.261.639419131' scope=spfile;
3]SQL>shutdown immediate

6. Start the instance.

Note:
In-order to have Multiple Copies/ Multiplexed Version of the controlfiles, repeat steps 3-5