Oracle Database Tips by Donald Burleson

Oracle10g Grid Computing with RAC
Chapter 15 - RAC Migration Topics

Manual Conversion Procedure

16. Configure the net service entries for the database and instances and address entries for the LOCAL_LISTENER for each instance and REMOTE_LISTENER in the tnsnames.ora file and then copy it to all nodes.
     

17. Create an SPFILE from the PFILE using the command:

CREATE SPFILE='Spfile_name' from pfile='pfile_name'

(the file names should be full path names)

18. If you are not using a cluster file system, then ensure that the SPFILE is on a raw device.
     

19. Now create a $ORACLE_HOME/dbs/initSID.ora file on UNIX-based systems or a %ORACLE_HOME%\database\initSID.ora file on Windows-based systems that contains the following entry:

spfile='spfile_path_name'

20. where spfile_path_name is the complete path name of the SPFILE.
     

21. Add the configuration for the RAC database and its instance-to-node mapping using SRVCTL (see Chapter 8 for the format).
     

22. Start the RAC database using SRVCTL (see Chapter 8 for the format).

Once the database has been started with SRVCTL, your conversion process is complete and the following SQL statement can be used to see the status of all the instances in your converted RAC database:

select * from v$active_instances

Conversion of a Single Instance on a Cluster Running from a RAC-Disabled Oracle Home

On UNIX/Linux-based systems, where re-link of the Oracle executables is possible, having a single-instance running from a RAC-disabled Oracle home installation is possible (if improbable) if a one-node cluster (with RAC) installation was performed, but later the RAC feature was disabled by unlinking it from the oracle binary before creating the single instance database. An alternative method is to select the "local", "non-cluster" selection on the Node Selection screen in OUI to create a non-RAC-enabled single-instance home on a cluster. Use the following technique to convert this special type of single-instance database into a RAC database:

1. On the cluster node where the single-instance database is running, create a duplicate template of the database as described in precious sections using DBCA.
    

2. Change the working directory to the lib subdirectory in the rdbms directory under the Oracle home.

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