New installation cannot connect to MySQL database

Just downloaded this app for an evaluation
Using Centos, installed Apache, PHP and the Plugins, and MySQL demon
Unpacked the zip file under the document root
Opened the first time installation page to configure, tweaked the PHP setting as recommended
I cannot save the configuration as it is failing to connect to the MySQL server

SQLSTATE[HY000] [2003] Can't connect to MySQL server on '127.0.0.1' (13)
dsn = mysql:host=127.0.0.1;port=3306

On the CLI I can connect to the MySQL server using the root user and the password I configured for it (not the default)
I can see via the client that it is running on the default port 3306
It does not look like there is a database for this application (what would it's name be) and I assume the configuration process I am trying to do creates it?

Is there something else I need to setup or configure? Where should I be looking for the problem?
The application is producing no logs yet and the MySQL log has no relevent information about attempted logins.
 

Hi,

I had exactly the same issue few day ago and I solve it by using a localhost as host name, not 127.0.0.1.
Reason for it is in fact that mysql on CentOS is storing root user as root@localhost and using 127.0.0.1 will not find a match.

As babynus wrote, mysql root user is root@localhost.