Cause
You are attempting to mount a secondary database that has already been mounted by your instance.
You are attempting to mount a secondary database that has already been mounted by your instance.
to mount it. To establish access, use the ALTER DATABASE <linkname> OPEN command to open the database.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12300.htm
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