Oracle Solution for Error ora-12321

ORA-12321: database (link name string) is not open and AUTO_MOUNTING=FALSE

What triggered the Error:

The secondary database that your instance is attempting to mount is not open and automatic mounting has not been enabled.

What should we do to fix it:

Manually mount and open the secondary database using ALTER DATABASE with the OPEN and MOUNT options. Alternately, to allow your instance to automatically mount and open secondary databases, set the AUTO_MOUNTING parameter in the parameter file to TRUE.

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