ORA-16757: unable to get this property''s value
Cause: The Data Guard broker failed to get the value for the specified property, possibly because the specified property''s value is not available for the current database role.
Action: If the specified property''s value is not available for the database''s current role, please specify this property for a database for which it is available. Otherwise, check the Data Guard broker log for more details.
Error Type: ORA