ORA-15021
        Parameter "parameter_name" is not valid in instance_name instance.
        - parameter_name: The user-supplied value.
- instance_name: The current instance being started.
        Cause
        The specified parameter was not valid or not supported when starting an instance of this type.
        Action
        Remove the specified parameter from the initialization parameter file and reissue the command.
        
     
    
    
        ORA-15021
        parameter "string" is not valid in string instance
        
        
        Cause
        The specified parameter was not supported when starting an instance of this type.
        Action
        Delete the specified parameter from the INIT.ORA file.
        
     
    
    
        ORA-15021
        parameter "string" is not valid in string instance
        
        
        Cause
        The specified parameter was not supported when starting an instance of this type.
        Action
        Delete the specified parameter from the INIT.ORA file.