To guard against users uploading huge files, I've got this in my php.ini 
file:

; Maximum size of POST data that PHP will accept.
post_max_size = 10M


On a server running Ubuntu Linux. The PHP version:

root@ldc310:/etc/php5/cli# php -v
PHP 5.1.6 (cli) (built: Nov 28 2007 22:52:49)

I just uploaded a 28 meg file to the server. I have a PHP script that 
automatically resizes the images to less than a meg. However, I was 
(hoping) assuming that the upload should have failed, before the PHP 
script ever had the chance to resize the file. How do I limit how much 
our users can upload? I really don't want the users to have the power to 
upload 30 or 40 or 50 meg files.

The server does have Plesk installed, which I know, in times past, has 
found ways to undermine the settings in php.ini. For instance, for 
open_basedir, the value that gets written in the httpd.conf file, in 
each vhost directory, takes precedence over whatever I put in php.ini. 
But I've never seen Plesk undermine the importance of the post_max_size 
setting, nor can I imagine where Plesk might store such a conf setting 
if it did.

Any thoughts on what might be wrong? Are there other places some 
configuration data might be taking precedent?