Cause
An attempt was made to set SCAN_INSTANCES or CACHE_INSTANCES using the ALTER SYSTEM command while the database was mounted in exclusive mode.
An attempt was made to set SCAN_INSTANCES or CACHE_INSTANCES using the ALTER SYSTEM command while the database was mounted in exclusive mode.
SCAN_INSTANCES / CACHE_INSTANCES may not be set unless running Oracle Real Application Clusters mounted in CLUSTER_DATABASE mode.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12700.htm
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