..you are experienced with running Linux servers? I have a strange problem with one of my servers having a terribly slow upload speed via HTTP (like phpbb attachments for example). I've checked the php configuration and firewall settings with a fine toothed comb but to no avail, uploads via http are going about 5kb/s. On the FTP it goes about 1.5mb/s - so what gives? Any ideas?

Heres some things I've tried:

* Checked the ownership and permissions of the /tmp and the account's folders sending the data. I've tried fiddling with every type of ownership.
* I've tried all the PHP handlers available to me: suphp, cgi, fcgi and dso.
* I've tried reinstalling apache with several different configurations including the most basic.
* I've checked upload max size, memory limit, file max size and other php.ini options.
* I've checked the firewall, and even disabled the firewall to see if it was the problem - no change.
* I've checked htaccess files and anything that might influence the upload. I tried dummy folders with nothing else in them.
* I've tried several different upload scripts just incase it's that.
* I've tried fiddling about with the kernel and mounting /tmp as a file system.
* I've checked the dns settings.
* I've turned on/off security settings such as moddir, brute force etc.

Server is using PHP 5.3.2 on Centos 6.3 64bit.

Oh dear, seems the fault was at my end - A VPN I installed had somehow caused the http upload speeds on this particular system to grind to a halt!