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<DIV><FONT face=Arial size=2>Hi Bob,</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Perhaps I am missing something here, but with my Postfix
setup (which is based on two instances of Postfix + amavisd-new + Cyrus),
messages are checked against a user database at the outer postfix, and rejected
during the SMTP connection for invalid recipients, before lmtp/etc. even sees
it. For me, this requires that user logins/authentication be handled
through a MySQL database, but is this an option for you? </FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>It avoids almost all of the backscatter issues... though
may not be the best setup for everyone.</FONT></DIV>
<DIV><FONT face=Arial></FONT> </DIV>
<DIV><FONT face=Arial>Take care,</FONT></DIV>
<DIV><FONT face=Arial>Anthony</FONT></DIV>
<DIV> </DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=bob3bob3@suddenlink.net href="mailto:bob3bob3@suddenlink.net">Bob
Bob</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A
title=info-cyrus@lists.andrew.cmu.edu
href="mailto:info-cyrus@lists.andrew.cmu.edu">Cyrus Maillist</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Friday, July 13, 2007 10:52
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Method to drop unknown user
messages to black hole</DIV>
<DIV><BR></DIV>Postfix & Cyrus<BR><BR>Have been finishing off the server
ready for accepting external smtp<BR>connections. No more
fetchmail...<BR><BR>I note that in todays spam environment more and more
administrators are<BR>choosing to black hole any messages with invalid
recipients. In a<BR>standard postfix setup this is pretty easy with
luser_relay. When<BR>however you use lmtp, local delivery really only looks at
/etc/aliases<BR>until it passes through to cyrus.<BR><BR>My first question is
a general one. Do you all choose to send<BR>reject/nonexistent user messages
or just black hole them? Rejecting is<BR>obviously the simplest solution but I
am concerned about being<BR>blacklisted from sending garbage back out. There
are ways of course to<BR>stop backscatter happening but I am also concerned
that there are valid<BR>bounces being created that the (real) sender needs to
know about. I'd<BR>like to hear what your solutions have been.<BR><BR>My
second question is how to you accomplish a black hole with cyrus? I<BR>had
thought that a "global" sieve script would do it but note that this<BR>is user
specific. I see nothing specific in lmtp that points to that either.<BR><BR>I
note this has been discussed previously but I didn't find an
actual<BR>resolution beyond allowing auto mailbox creation!<BR><BR>Thoughts
appreciated<BR><BR>Bob<BR>----<BR>Cyrus Home Page: <A
href="http://cyrusimap.web.cmu.edu/">http://cyrusimap.web.cmu.edu/</A><BR>Cyrus
Wiki/FAQ: <A
href="http://cyrusimap.web.cmu.edu/twiki">http://cyrusimap.web.cmu.edu/twiki</A><BR>List
Archives/Info: <A
href="http://asg.web.cmu.edu/cyrus/mailing-list.html">http://asg.web.cmu.edu/cyrus/mailing-list.html</A><BR></BLOCKQUOTE></BODY></HTML>