greylist whitelist for broken mail systems

Gary Mills mills@cc.UManitoba.CA
Fri Jan 9 16:59:14 UTC 2004

Since we started running a DCC greylist here, our spam has gone way
down.  However, we have received a few complaints from people who
could no longer send e-mail to our users.  Our sendmail logs showed
that their mail system sent the message once, and never retried it.
I've added some entries to the grey_whitelist file for each greylist
server to allow their broken mail systems to bypass greylisting.

Here's my current no-retry.wh file, which is included in grey_whitelist:

# Broken mail servers that do not retry after temporary
#	SMTP failures

# ZipLip Server 4.1
ok	substitute helo

# MERAK 3.10.110
ok	substitute helo

# GroupWise Internet Agent 6.5.1
ok	substitute helo

# IA Mail Server Version: 3.2.2
ok	substitute helo


With the exception of the last entry, the descriptions are taken from
their SMTP banner.  The last one is for the outgoing mail server of a
travel agency, and is taken from their Received header.  When I add
entries, I advise the sender to get their mail system fixed, but I
don't expect many to do so.

-Gary Mills-    -Unix Support-    -U of M Academic Computing and Networking-

More information about the DCC mailing list

Contact by mail or use the form.