ERROR 256: DB connection error in PGV_DB::createInstance(): SQLSTATE[HY000] [2002] No route to host

Fatal error: DB connection error in PGV_DB::createInstance(): SQLSTATE[HY000] [2002] No route to host in /var/www/vhosts/satria.de/httpdocs/ged/includes/classes/class_pgv_db.php on line 405