Your MySQL is not running for some reason.
Have you installed some modules ?
To 'control' the MySQL daemon,
Usage : /etc/init.d/mysqld {start¦stop¦status¦condrestart¦restart}
Example : /etc/init.d/mysql status
to show if it's running
Try "restart" mysqld and then :
cat /var/log/mysqld.log
This should show you what's happening exactly
[%sig%]