Warning: session_start(): Cannot find save handler 'redis' - session startup failed in /var/www/markets.traderfox.com/htdocs/include/prepend.php on line 21

Fatal error: Uncaught Error: Call to undefined function mysqli_connect() in /var/www/markets.traderfox.com/htdocs/include/class/DbHandler.class.php:51 Stack trace: #0 /var/www/markets.traderfox.com/htdocs/include/class/DbHandler.class.php(41): DbItem->connect() #1 /var/www/markets.traderfox.com/htdocs/include/class/DbHandler.class.php(17): DbItem->__construct(Array) #2 /var/www/markets.traderfox.com/htdocs/include/class/Db.class.php(10): DbHandler::getDb(Array) #3 /var/www/markets.traderfox.com/htdocs/include/class/Db.class.php(16): Db::create() #4 /var/www/markets.traderfox.com/htdocs/include/prepend.php(61): require('/var/www/market...') #5 [internal function]: tdf_autoload('Db') #6 /var/www/markets.traderfox.com/htdocs/include/class/Stock.class.php(600): spl_autoload_call('Db') #7 /var/www/markets.traderfox.com/htdocs/include/class/Stock.class.php(669): Stock::getStocks(Array, false, false, false, 1, true) #8 /var/www/markets.traderfox.com/htdocs/nachrichten/index.php(35): Stock::getStockById(15116592, false, false) #9 in /var/www/markets.traderfox.com/htdocs/include/class/DbHandler.class.php on line 51