Reallocate Enterprise Manager 11g Master Node in RAC 11gR2 ;

In this post, I am going to show you how to reconfigure the DB Console master node to a new existing node in the cluster. This is a 3 node Real Application Clusters environment. We are using Enterprise manager db console 11g to monitor the 3 nodes RAC as opposed to Oracle Enterprise Manager grid control or EM cloud Control.

First of all, you need to check the actual configuration; the following output is showing ca25db01 is the actual master enterprise manager node, and only the Enterprise manager agent is running on the remaining nodes; ca25db02 and ca25db03.

[oracle@ca25db01 ~]$ emca -displayConfig dbcontrol –cluster

STARTED EMCA at Nov 9, 2011 12:57:53 AM
EM Configuration Assistant, Version 11.2.0.0.2 Production
Copyright (c) 2003, 2005, Oracle.  All rights reserved.

Enter the following information:
Database unique name: cmsdb
Service name: cmsdb.oracle-class.com
Do you wish to continue? [yes(Y)/no(N)]: tes
Invalid input.
Do you wish to continue? [yes(Y)/no(N)]: Y
Nov 9, 2011 12:58:14 AM oracle.sysman.emcp.EMConfig perform
INFO: This operation is being logged at /opt/app/oracle/cfgtoollogs/emca/cmsdb/e                                                                                        mca_2011_11_09_00_57_53.log.
Nov 9, 2011 12:58:17 AM oracle.sysman.emcp.EMDBPostConfig showClusterDBCAgentMes                                                                                        sage
INFO:
****************  Current Configuration  ****************
 INSTANCE            NODE           DBCONTROL_UPLOAD_HOST
----------        ----------        ---------------------

cmsdb             ca25db01             ca25db01.oracle-class.com
cmsdb             ca25db02             ca25db01.oracle-class.com
cmsdb             ca25db03             ca25db01.oracle-class.com

Enterprise Manager configuration completed successfully
FINISHED EMCA at Nov 9, 2011 12:58:17 AM

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