[comp.mail.misc] How can I restrict/refuse an incoming SMTP connection?

mb@rex.cs.tulane.edu (Mark Benard) (08/26/90)

I have a problem with one particular host that is making SMTP connections
with us and then just hanging on, eating up lots of CPU time and eventually
making multiple connections which block our local sendmail from running the
queue.  Is there anything I can set in sendmail.cf or elsewhere to cause
connections from this host to be refused or to limit the time length of an
incoming SMTP session?

We are running U Toronto's sendmail on a Pyramid 9815.

Mark

jgk@osc.COM (Joe Keane) (08/29/90)

In my opinion this problem is better solved by calling up the site and telling
them to get their act together.  Chances are, if you're having the problem, so
are other people.

jeffe@sandino.austin.ibm.com (Peter Jeffe 512.823.4091) (09/01/90)

In article <4005@rex.cs.tulane.edu> mb@rex.cs.tulane.edu (Mark Benard) writes:
>I have a problem with one particular host that is making SMTP connections
>with us and then just hanging on, eating up lots of CPU time and eventually
>making multiple connections which block our local sendmail from running the
>queue.  Is there anything I can set in sendmail.cf or elsewhere to cause
>connections from this host to be refused or to limit the time length of an
>incoming SMTP session?

I can't think of any way to restrict connections from that host (without
hacking the code), but you can certainly use the r option to set the read
timeout.  E.g., doing "Or5m" will timeout the server's read after 5 minutes
and cause it to die.  Look for the timeout syslogs to tell you when it
happens (and with whom).

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