An unexpected condition happened in the Grid Infrastructure Management Repository.
1) Examine the accompanying ORA-nnnnn error messages. If possible, correct the issue reported. 2) Issue a 'srvctl status mgmtdb' command to determine the status of the Grid Infrastructure Management Repository database. If it is not online, examine the database instance alert log to determine what happened. 3) If you are unable to determine or correct the problem, contact Oracle Support Services.
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Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/crsus.htm