High spam mail traffic -> max mysql connections
I'm running into a problem and am looking for a good solution to fix this.
Eventually everybody running ispconfig3 will run into this problem!
After doing a clean Debian install and fresh ispconfig 3 installation (18.104.22.168)
i've added some domains, domains of which i know are attractive to send mail to.
The problem I'm running into is the MySQL connections.
All mails that get send to the server need a MySQL connection to check if it's black-,white-listed, filter rules, alias settings etc etc.
So what happens when your server gets hammered by spammers .. max MySQL connections .. and your sites will show blank pages, display MySQL errors etc .. I've set the max connections up to 250 now, and set the timeout for MySQL connections a lot lower (i think it was 120 or 180sec).
Doesn't work, I'm still running into max connections.
I'm using RBL (zen.spamhaus.org), but it looks like there are still connections being made, in a high tempo.