I keep getting this message randomly in various operations (logging out, saving a change, pulling up a contact). Sometimes the operations work flawlessly for hours. Other times they crash, always with the message below.

The system goes down for several minutes and the next user to try to log in winds up in the same spot logged into the app where the user crashed out.

Any idea what could be causing this. It's a recent install (last week or so) and it has been happening right from the start.

Fatal error: session_start(): Failed to initialize storage module: user (path: /tmp) in /hsphere/local/home/intassag/sugarcrm.sh76.com/SugarSuite/index.php on line 181

OS Linux
MySQL
Appache
PHP
MySql
SugarCRM
All current non-beta releases