For the past few weeks, our businesses mail server has been intermittently freezing. I've ready through multiple fixes and applied some of them, but I am lost and must ask for help.
Our mail server runs our staff email, (RoundCube and Squirrelmail) and a WordPress install for our Intranet. We are running Ubuntu 10.04, Sendmail, Dovecot, Apache2 and PHP 5.3.2. I have updated all installs to the latest versions that are supported by Ubuntu.
At different times throughout the day, our system CPU use will jump to 100% (of both processors) while monitoring them using HTOP. The output of HTOP always lists these entries as the offending processes, with higher CPU use, of course:
5892 www-data 20 0 64404 25092 6816 S 0.0 0.6 0:01.71 /usr/sbin/apache2 -k start
I am also monitoring Apache using the mod_status module.
I have attached a screenshot of my Server Status page during one of the freezes. The /email entries are RoundCube and the /intranet entries are Wordpress.
I was hoping someone who has more knowledge of Linux/Apache would be willing to help me out.