Warning: require_once(DB.php): failed to open stream: No such file or directory in /opt/app-root/src/scripts/kds_base.php on line 2

Fatal error: require_once(): Failed opening required 'DB.php' (include_path='.:/opt/app-root/src:/opt/rh/rh-php70/root/usr/share/pear') in /opt/app-root/src/scripts/kds_base.php on line 2