Cause
The number specified on the OPEN_MOUNTS parameter in the parameter file exceeds the maximum allowed (255).
The number specified on the OPEN_MOUNTS parameter in the parameter file exceeds the maximum allowed (255).
Change the value of this parameter so that it reflects the actual number of possible open mounts to secondary databases. This must be less than 255.
Try the following links for this error:
http://docs.oracle.com/cd/E16655_01/server.121/e26079/e12300.htm
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