Author: Chris Edwards Date: To: exim-users Subject: Re: [exim] Exim 4.68 defeats spammers!
On Sat, 1 Sep 2007, Mark Rigby-Jones wrote:
| In this particular case, they were - in fact they were even opening
| multiple simultaneous connections (until I dropped
| smtp_accept_max_per_host from 4 to 1 for off-net hosts) and re-
| connecting quite aggressively each time a connection was timed out.
| This, from numerous (dozens, certainly) different IP addresses to
| multiple mail servers on our side. After I made those changes, the
| number of concurrent connections began to drop down from being nailed
| up to the limit as it had been since the attack started, allowing
| legitimate emails to get through.
