def _configure_root_logger(self):
        """Initialise logging system"""
        root_logger = logging.getLogger()
        root_logger.setLevel(logging.DEBUG)
        if self.args.verbose:
            handler = logging.StreamHandler(sys.stdout)
        else:
            handler = logging.handlers.RotatingFileHandler(
                common.LOG_FILE,
                maxBytes=common.MAX_LOG_SIZE,
                backupCount=common.MAX_LOG_COUNT
            )
            handler.setLevel(logging.INFO)
        handler.setFormatter(logging.Formatter(common.LOG_FORMAT))
        root_logger.addHandler(handler)
Initialise logging system