Those should be rejected during the smtp session, any bounce message should be generated by the sender's server. Maybe you are generating delivery failure messages for local users?<br /><br /><br />---- Original Message ----<br />From: "Chuck Tetlow" <chuck@tetlow.net><br />Sent: 9/27/2017 11:57:38 PM<br />To: "BlueOnyx General Mailing List" <blueonyx@mail.blueonyx.it><br />Subject: [BlueOnyx:21426] Re: localhost sending 14K emails in a month?<br /><br /><HTML>
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Probably "backscatter".
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<br />Someone sends a message to a random address on your server, and the server send back a error reply if that username/e-mail address doesn't exist. The addresses are compiled by using the book of names for babies, and other lists - all trying to guess valid e-mail address names. If it fails or bounces - no big deal to them. If it works, then they have a valid e-mail address they can sell for a few pennies.
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<br />Unfortunately, in the meantime - your server is kept busy sending out ridiculous numbers of error messages. And sometimes, can even get blacklisted for all those error messages.
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<br />Chuck
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<br /><font size="2"><b>---------- Original Message
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From: Lewis Gardner <lewisg@iglou.com>
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To: BlueOnyx General Mailing List <blueonyx@mail.blueonyx.it>
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Sent: Thu, 28 Sep 2017 00:01:17 -0400
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Subject: [BlueOnyx:21425] localhost sending 14K emails in a month?
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According to Usage Information, Email, Senders localhost on one of my
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5209R servers has sent 13,990 emails this month. Mostly during one week
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and one other day.
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Is there any reasonable explanation for this behavior?
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What to do?
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_______________________________________________
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Blueonyx mailing list
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Blueonyx@mail.blueonyx.it
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<a href="http://mail.blueonyx.it/mailman/listinfo/blueonyx" target="_blank">http://mail.blueonyx.it/mailman/listinfo/blueonyx</a>
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