Security Incidents mailing list archives

Re: ***SPAM*** Re: Massive SPAM Increase {-2.6} {-2.6}


From: benfell () raven cybernude org
Date: Mon, 16 Oct 2006 10:04:30 -0700

On Fri, 13 Oct 2006 22:52:12 -0500, Paul Schmehl wrote:
--On October 13, 2006 10:46:34 PM -0400 Valdis.Kletnieks () vt edu wrote:

I'm not sure what you mean by "split inbound and outbound", but any 
outbound MX host *should* be listed in DNS.  You only list one - 
smtp.vt.edu.  192.82.162.213 is reversible, so it would get points for 
being honest about its IP/hostname, but it would lose points for not being 
listed in DNS as an MX.  The overall score would determine if the mail was 
rejected, but I doubt that it would be.

Wrong.  Completely wrong.  Any UNIX-like box with qmail can be configured
to send mail out.  My laptop, for example.  But my domains only receive mail
at the servers designated as MX hosts in DNS.

Your idea that an outbound mail host should be listed in DNS indicates a
complete misunderstanding of the purpose of an MX record.  These records
indicate to other MTAs where they should deliver mail *to*, not where they
should accept mail from.



-- 
David Benfell, LCP
benfell () parts-unknown org
---
Resume available at http://www.parts-unknown.org/

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