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Date: Thu, 30 Jan 1997 17:28:56 -0800
From: Jim Shankland <jas@flyingfox.COM>
Message-Id: <199701310128.RAA18024@saguaro.flyingfox.com>
To: allenh@wtrt.net, freebsd-isp@FreeBSD.org
Subject: Re:  Simple sendmail question
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> Email is working ok on my server.  I have one question/problem.
> When someone sends mail to a nonexistant address, I get the
> famous "config error: mail loops back to me" error message.
> Mail to/from valid addresses work fine.  Is this normal?  Or, is
> there something in the config file that needs tweaking?

You're using a wildcard MX, right?  So if someone sends mail
to foobarola.wtrt.net, it ends up on your mail host.  But your
mail host tries to deliver to foobarola.wtrt.net, which doesn't
really exist, so it falls back to the wildcard MX, and tries
to deliver to itself, and barfs.

Solution:  Either lose the wildcard MX (my personal preference),
or make sendmail on your mail server strip off any host stuff
to the left of wtrt.net before processing, so that, e.g.,
"joebob@foobarola.wtrt.net" gets rewritten to "joebob@wtrt.net"
before it attempts delivery.

Jim Shankland
Flying Fox Computer Systems, Inc.