Confusing PDO-only problem : Can't connect through socket/Access denied/Can't connect to server (shared host)

Question

So the problem changed from what it was, i'll leave the original question below to prevent bad reviews on answers like I had after someone editing his question I answered :

So I am working on a (really lame) shared hosting which has PDO installed, but it doesn't work. With default parameters

<?php
try {
    $dbh = new PDO('mysql:host=localhost;dbname=THE_DB_NAME', 'THE_USER', 'THE_PASSWORD');
    echo 'Connected to database';
    }
catch(PDOException $e)
    {
    echo $e->getMessage();
    }
?>

it throws this message :

SQLSTATE[HY000] [2002] Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

With a simple mysql_connect, it works.

And the socket path seems correct (both phpinfo and this query :

show variables like 'socket';

confirm.

Localhost redirects to 10.103.0.14 (this data comes from mysql_get_host_info() and in phpMyAdmin)

In the PDO, if i replace localhost by 127.0.0.1 i will get

SQLSTATE[HY000] [2003] Can't connect to MySQL server on '127.0.0.1' (111) 

And if i replace localhost by 10.103.0.14 :

Access denied for user 'USER_NAME'@'10.103.0.14' (using password: YES

Both IP adress (127.0.0.1 and 10.103.0.14) work with mysql_connect.

So apparently the problem comes from the PDO connection.

Does somebody knows where this could come from, or/and any way to fix it ?

Some server datas :

The PHP Version : 5.2.10 You can see the server's phpinfo : http://web.lerelaisinternet.com/abcd.php?v=5 No command line possible. (i know it should be the tech suport's job, but they're reaaaaaly slow)

Thanks

Previous question :

How to find the mysql.sock on a shared host (tricky way needed...)

So today's problem is : The PDO connection doesn't work on a shared host, and it's supposed to (it's installed on the server). Just a basic PDO connection :

<?php
try {
    $dbh = new PDO('mysql:host=localhost;dbname=THE_DB_NAME', 'THE_USER', 'THE_PASSWORD');
    echo 'Connected to database';
    }
catch(PDOException $e)
    {
    echo $e->getMessage();
    }
?>

throws this message :

SQLSTATE[HY000] [2002] Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)

A regular mysql connection :

mysql_connect("localhost", "THE_USER", "THE_PWD") or die(mysql_error()); 
mysql_select_db("24DLJLRR1") or die(mysql_error());;
echo 'Connected to database <br/>';

works fine.

So apparently it cannot find the .sock. I think specifying the correct address should work, i tried some "classic" mysql path that I found on internet, without success. The phpinfo says it is at this adress (/var/lib/mysql/mysql.sock) (The PHP Version is 5.2.10) You can see the server's phpinfo : http://web.lerelaisinternet.com/abcd.php?v=5

So i am trying to figure out where the hell it is !!! I tried to look in the phpMyAdmin interface, but i couldn't find the info, plus it seems that phpMyAdmin connects to a different server (it has a different IP adress, and trying to connect to it with php gives a "Wrong password" error). The mysql_connect also connects to this adress, i think it redirects to a different server with some internal password/login.

Well if you have any idea of how to obtain this info (the provider's technical support is "fixing the problem"... it's been 1 month...). Also maybe the problem comes from somewhere else, but the same stuff works on other shared hosts...

The need of PDO is because I use the Symfony framework with Doctrine for this website, and the Doctrine plugin needs PDO... I don't want to redo the website from scratch !

Thanks for your help !

Answer 1

This was already marked as answered, but not really solved (without changing databases). So, just in case someone like me also experiences this problem...

The easiest way to fix this is to first get the socket path (either by looking in the php.ini file or by using: phpmyadmin or the console (or construct it in mysql or mysqli)

...to run the following query (anything but PDO):

show variables like 'socket';       //as mentioned by symcbean

THEN, in the PDO connection string, change it to use the socket instead of a hostname:

$dbc = new PDO("mysql:unix_socket=/var/run/mysqld/mysqld.sock;dbname=$DBName", $User, $Password, array(PDO::ATTR_PERSISTENT => true)); // using persistent connections

This worked for me.

Answer 2

FWIW, I had this issue and changed my host from 'localhost' to '127.0.0.1'.

I have no clue why localhost wasn't working, but that did the trick.

Odd thing is, we have tons of servers and it works on almost every one using 'localhost'

Answer 3

Is your server running with SeLinux enabled (enforcing)? If it is, try running as root:

# setsebool -P httpd_can_network_connect on

Answer 4

Can you try 127.0.0.1 as the server name instead of localhost?

IIRC, with some mySQL drivers / adapters, this decides whether the socket is used for establishing the connection or not.