Cause
The database was started in parallel mode. To change the DBID, the database must be mounted exclusively.
The database was started in parallel mode. To change the DBID, the database must be mounted exclusively.
Shut down the database and start it in exclusive mode.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/nidus.htm
https://community.oracle.com/message/10289599
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