Configure /Reconfigure DB Control in RAC

Login in to one the cluster node and run the below command to drop the existing configuration.

$ emca -deconfig dbcontrol db -repos drop

sqlplus "/as sysdba"
DROP USER sysman CASCADE;

DROP PUBLIC SYNONYM setemviewusercontext;

DROP ROLE mgmt_user;

DROP PUBLIC SYNONYM mgmt_target_blackouts;

DROP USER mgmt_view;

Configure db console:

emca -config dbcontrol db -repos create -cluster

Start dbconsole:

$ emctl start dbconsole

Check the DB Control configuration on the cluster:

$emca -displayConfig dbcontrol -cluster