Best Way to Block Relaying Attempts

From: Steve Lowe <Steve.Lowe_at_aurora.edu>
Date: Thu, 02 Jan 2003 13:45:07 -0600 (CST)

Good afternoon

Like many system managers, we struggle with the best way to block
relaying attempts against our MAIL server. At the moment, we have
very strict rules in our sendmail configuration which results in
the error messages below my signature.

But, what is the best way to effectively block this IP address?
We trapped over 300+ attempts in one 24 hour period. Our network
manager is checking his PIX Firewall configuration. But, if I have
to do it on the MAIL server, do we have any other options except
sendmail?

Thanks in advance.

 -- Steve Lowe
    Information Services
    Aurora University


-----------------------LOG MESSAGES----------------------------

Jan 2 13:12:17 mail sendmail[239369]: ruleset=check_relay,
arg1=24-196-110-112.jvl.wi.charter.com, arg2=24.196.110.112,
relay=24-196-110-112.jvl.wi.charter.com [24.196.110.112], discard

Jan 2 13:12:17 mail sendmail[239369]: h02JCHOZ239369: ruleset=check_rcpt,
arg1=<mrscruella_at_yahoo.com>, relay=24-196-110-112.jvl.wi.charter.com
[24.196.110.112], reject=550 5.7.1 <mrscruella_at_yahoo.com>... Relaying denied

Jan 2 13:12:17 mail sendmail[239369]: h02JCHOZ239369:
from=<pbeallis_at_aurora.edu>, size=0, class=0, nrcpts=0, proto=SMTP, daemon=MTA,
relay=24-196-110-112.jvl.wi.charter.com [24.196.110.112]
Received on Thu Jan 02 2003 - 19:50:19 NZDT

This archive was generated by hypermail 2.4.0 : Wed Nov 08 2023 - 11:53:44 NZDT