First of all, this is on our new box, just recently installed and with just a couple of testdomains, and I think 5 mail accounts. The box is a Fedora Core 6 with Virtualmin Pro. I have done some comparing with our old server that is currently hosting about 40 domains and 200 mail accounts, this server is running Fedora Core 4 and Virtualmin Pro.
I did see this in the kernel log a few times: possible SYN flooding on port 110. Sending cookies. Is there somethin I can to do about this?
Does this have someting to do with all the Dovecot processes: dovecot 0.0 % pop3-login There was about 130 of these dovecot processes. (the server only have 5 mail accounts)
And the System info in Virtualmin did show 219 running processes... and also the CPU load averages on this server was about 3 times as high than on our old box that host abot 40 domains and a few hundred mail accounts, also the running processess was 96 on our old server.
I have temporarily shut down Dovecot on our new box.
Please let me know if you have any ideas or suggestions.