Lindsay Haisley writes:
I'm having some problems on my courier mail server today what are
probably dictionary spam attacks on one or more of the domain names I
host. The network connections table fills up with dozens of partially
completed SMTP network sessions and after a while the SMTP server just
locks up and won't accept any more connections.
To solve this I'm ramping down some of the default timeouts which can be
spec'd in files such as esmtptimeout and others like it. The doc for
esmtptimeout states the file contains a single text number which
specifies the timeout in seconds unless a "m" or "h" is appended to it
to specify minutes or hours. Does this format also apply to other
similar files such as esmtptimeouthelo and esmtptimeoutdata?
Yes, but these specific settings are for outgoing esmtp. For incoming esmtp,
the settings are esmtptimeout and esmtptimeoutdata.
I'd also like to have the option to drop SMTP connections outside of the
LAN for which the IP address of the connecting host has no PTR record
and won't reverse resolve to a name. Is there any way to do this in
Courier?
No, not directly. The only thing you can do is to take the qmail approach,
and have couriertcpd invoke your wrapper, that checks TCPREMOTEIP and
TCPREMOTEHOST, and the invokes courieresmtpd itself.
5 messages in net.sourceforge.lists.courier-usersRe: [courier-users] timeouts and ptr ...
