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Question Undelivered Mail Returned to Sender

yabado

Regular Pleskian
My server is getting hammered with spam and for some reason the server still sends bounce messages with subject "Undelivered Mail Returned to Sender" even though everything is set to Reject.

Why is it still sending these emails. Causes tons of backscatter.

Running Linux , Cloudlinux and 12.5.x
 
Where exactly have you set "everything to Reject"? The only place I'd know of is the catch-all control for undefined mail addresses. "Reject" in that case does not mean "silently swallow", but return a REJECT information to the sender. If you do not want to receive mail on a specific domain at all, you can uncheck "Activate mail service on this domain" on the catch-all control page.
 
I have it set on each domains Mail Settings for the "What to do with mail for non-existent users" option. The options are Bounce, Forward and Reject.
Are you saying that Reject STILL sends a bounce message?

I just want a way to have ALL mail sent to non-existent users ( entire server, all domains ) just goes away, no email response, just dies.

Is there a way to do this?
 
The normal solution to do that is to send all incoming mails to /dev/null or to deny incoming mail service in general. As the first does not work on Plesk, because Plesk complains about invalid mail format if you try to forward mail to /dev/null, I suggest to deactivate mail service by unchecking "Activate mail service on this domain".
 
The normal solution to do that is to send all incoming mails to /dev/null or to deny incoming mail service in general. As the first does not work on Plesk, because Plesk complains about invalid mail format if you try to forward mail to /dev/null, I suggest to deactivate mail service by unchecking "Activate mail service on this domain".
Thanks for taking time to reply, but that is not a realistic option. If anyone else has a way to prevent this from happening please chime in.

There has to be a direct postfix config I can add to get this done.
 
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