Warning: mysqli::__construct(): php_network_getaddresses: getaddrinfo failed: Name or service not known in /var/www/html/index.php on line 15

Warning: mysqli::__construct(): (HY000/2002): php_network_getaddresses: getaddrinfo failed: Name or service not known in /var/www/html/index.php on line 15
Failed to connect to MySQL: php_network_getaddresses: getaddrinfo failed: Name or service not known