Convert RAC instance to SINGLE instance DATABASE

converting RAC instance to SINGLE instance database
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In this article, see how the rac instance database is converted into single instance database
step1:stop instance 2 from any node
step 2:change the parameter cluster_database
step 3: [optional]
removing information from clusterware

[root@rac1 bin]# ./srvctl stop instance -i test2 -d test
[root@rac1 bin]# ./srvctl remove instance -i test2 -d test
Remove instance test2 from the database test? (y/[n]) y
[root@rac1 bin]#



[oracle@rac1 ~]$ . oraenv
ORACLE_SID = [oracle] ? test1
The Oracle base for ORACLE_HOME=/u01/new/oracle/product/11.1.0/db_1 is /u01/new/oracle
[oracle@rac1 ~]$ sqlplus '/as sysdba'

SQL*Plus: Release 11.1.0.6.0 - Production on Wed Dec 9 11:10:25 2009

Copyright (c) 1982, 2007, Oracle. All rights reserved.


Connected to:
Oracle Database 11g Enterprise Edition Release 11.1.0.6.0 - Production
With the Partitioning, Real Application Clusters, OLAP, Data Mining
and Real Application Testing options

SQL> startup
ORA-01081: cannot start already-running ORACLE - shut it down first
SQL> show parameter cluster_database

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
cluster_database boolean TRUE
cluster_database_instances integer 2
SQL>
SQL> alter system set cluster_database=false scope=spfile;

System altered.

SQL> shu immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.

Total System Global Area 481267712 bytes
Fixed Size 1300716 bytes
Variable Size 167773972 bytes
Database Buffers 306184192 bytes
Redo Buffers 6008832 bytes
Database mounted.
Database opened.
SQL> show parameter cluster_database

NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
cluster_database boolean FALSE
cluster_database_instances integer 1
SQL>

removing the database information from clusterware
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[root@rac1 bin]# ./srvctl status database -d test
Instance test1 is not running on node rac1
[root@rac1 bin]# ./srvctl status database -d test
Instance test1 is not running on node rac1
[root@rac1 bin]# ./srvctl stop instance -i test1 -d test
[root@rac1 bin]# ./srvctl remove instance -i test1 -d test
Remove instance test1 from the database test? (y/[n]) y
[root@rac1 bin]# ./srvctl stop database -d test
[root@rac1 bin]#

regards,
rajeshkumar govindarajan