Strange Sendmail Sessions

[Chris Stone]

On Thu, 2006-10-12 at 16:21 -0400, Stephen Conway wrote:
> I have a problem where I am getting a lot of sendmail sessions opening up
> similar to below:
> 
> 0:00 sendmail: k9CJgJRU012733 c647683-42.impsat.com.co [64.76.83.42] (may be
> forged): DATA
> 0:00 sendmail: k9CJlhwE014949 movaris-nxds1-89.hicap.alink.net
> [67.131.237.89]: DATA
> 
> A bunch of these keep coming in from various different networks, but they
> all stay around and eventually my MAX Daemon Children vaule is reached.  The
> question is, can this be a network issue where these sessions are not
> completing?  Also, how can I get sendmail to kill these old sessions after X
> minutes or something?

Started seeing this myself on my MailScanner servers (3 of them)
yesterday. What I've done to mitigate the 'damage' is adding the
following in my sendmail_in.mc file:

FEATURE(`access_db',`hash -T<TMPF> -o /etc/mail/access.db')dnl
FEATURE(delay_checks)dnl
FEATURE(`blacklist_recipients')dnl
FEATURE(`ratecontrol',`nodelay',`terminate')dnl
FEATURE(`conncontrol',`nodelay',`terminate')dnl

And then in my access file:

# connections control and throttling
ClientConn:                     5
ClientRate:                     15

Has helped a lot.


Chris


-- 
Chris Stone <axisml at gmail.com>
AxisInternet, Inc.