Warning: mysqli_connect(): php_network_getaddresses: getaddrinfo failed: Name or service not known in /var/www/html/configall.php on line 3

Warning: mysqli_connect(): (HY000/2002): php_network_getaddresses: getaddrinfo failed: Name or service not known in /var/www/html/configall.php on line 3
ERROR: Could not connect. php_network_getaddresses: getaddrinfo failed: Name or service not known