Remote Qt Database connection

How to solve the error:

QSqlError("2003", "QMYSQL: Unable to connect", "Can't connect to MySQL server on '112.17.98.18' (111)")

When I try to connect to the remote database it shows the error given above. But when I connect to localhost it does not show any error.

My code is below. Please help if you can.

QSqlDatabase db = QSqlDatabase::addDatabase("QMYSQL");
        db.setHostName("112.17.98.18"); // fake ip ;
        db.setPort(3306);
        db.setDatabaseName("root");
        db.setUserName("root");
        db.setPassword(" ");
        db.open();