def METHOD_NAME(data_dirs_list):
    try:
        for data_dir in data_dirs_list:
            logger.info('Backing up pg_hba.conf for %s' % data_dir)
            # back it up
            os.system('cp %s/pg_hba.conf %s/%s'% (data_dir, data_dir, PG_HBA_BACKUP))
    except Exception as ex:
        raise Exception('Failed to backup pg_hba.config file %s' % ex)