Oracle Solution for Error ora-12808

ORA-12808: cannot set string_INSTANCES greater than number of instances string

What triggered the Error:

An attempt was made to set SCAN_INSTANCES or CACHE_INSTANCES using the ALTER SYSTEM command to a value larger than the number of available instances.

What should we do to fix it:

See the accompanying message for the current allowable maximum value, or set SCAN_INSTANCES / CACHE_INSTANCES to ALL.