PHP 5.3 Upgrade - Can't Connect to MySQL Server

I've done a bit of research on this today, but nothing seems to address this issue. I recently upgraded to PHP 5.3.3 from 5.1.6, as well as upgraded MySQL to 5.5 from 5.0. Afterwards, the following code generates an error saying "Can't connect to mysql database":

$connection =  mysql_pconnect($dbhost, $dbusername, $dbpassword);
if (!$connection) {
  //Can't connect
  die('Could not connect: ' . mysql_error());
  return;
}

And get the following error:

Warning: mysql_pconnect(): Can't connect to MySQL server on '199.59.157.103' (13) in /var/www/html/ws/Cust/customerWS_1_1.php on line 19 Could not connect: Can't connect to MySQL server on '199.59.157.103' (13)

I am able to connect to the remote host via the command line, and have tried everything from resetting the password to shutting down IP Tables. I'm kind of at a loss - so any help would be 开发者_如何学Cappreciated.

We had a similar problem with the same error message "Can't connect to mysql database" and maybe the following points will be also usefull:

• check mysql user privileges (in our case and with external connections we had the old server IP address (allow access) in the table) GRANT ALL PRIVILEGES ON tablename.* TO 'username'@'145.1.1.2'; -> reload privileges after changes (FLUSH PRIVILEGES;)

• disable the SELinux parameter. In new Plesk versions (>10?) this would be set enabled automatically... --> in /etc/selinux/config change the line that says:

  SELINUX=enforcing to SELINUX=disabled See further details: http://googolflex.com/?p=482

There is a PHP 5.3 mysql driver restriction related to old authentication scheme hash stored in the database by previous mysql server. This could cause a problem with stored passwords so the databases will be unaccessible with old passwords.

To solve the problem you should recreate the mysql users with the same login and same password.

When you say "I am able to connect to the remote host via the command line" do you mean, you are connecting to the MySQL server REMOTELY? Or that you are SSHing to your MySQL server and connecting to it from the MySQL server's command line? If the latter, it's possible that when you upgraded to MySQL 5.5 you accidentally stopped MySQL from binding / listening on a public IP. Check your my.cnf.

Otherwise: is your PHP code being run on the same server as your MySQL server? It's possible that your permissions could be off. MySQL permissions are very particular about connecting to the MySQL server via it's IP address if the client only has access to connect from 'localhost', and vice-versa.

First you should make sure that the connect parameters $dbhost, $dbusername and $dbpassword are correct. Assuming these are correct, you should check your mysql ini settings. I would assume that the bind-address is set to 127.0.0.1 or localhost, but not to a public IP address.

Also note that it's a security risk if you can connect to mysql from a public IP address. You may want to look into a solution that does not require such connection.