Warning: mysqli::__construct(): php_network_getaddresses: getaddrinfo for mysql_db failed: Name or service not known in /var/www/html/services/Access.php on line 10

Fatal error: Uncaught mysqli_sql_exception: php_network_getaddresses: getaddrinfo for mysql_db failed: Name or service not known in /var/www/html/services/Access.php:10 Stack trace: #0 /var/www/html/services/Access.php(10): mysqli->__construct('mysql_db', 'root', 'admin-db-pass', 'gaschtToGo') #1 /var/www/html/index.php(16): Access->__construct() #2 {main} thrown in /var/www/html/services/Access.php on line 10