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Re: Response from Cyber Promotions (fwd)

  • From: Taner Halicioglu
  • Date: Mon Apr 21 13:54:06 1997

On Mon, 21 Apr 1997, Doug McIntyre wrote:

> But most of the bulk spammer programs out there don't follow MX
> records. They blast directly into the sendmail port of the primary
> machine, and if they can't do that, they leave it at that and move
> on.. Blocking spam sites directly at the sendmail level (with
> tcp_wrappers), does effectively block out bad domains. 

You sure about not following MX'?  There is a machine, '', but it
doesn't accept mail, and there's an MX pointing to out real mail machine,
yet we constantly get spam :-)

Otherwise everyone would've used this trick to avoid spam :)

Some of the sendmail rules listed at, like the
one that forces the MAIL FROM line to actually resolve, would probably
block a lot of spam, too.  But I was wondering if this requires the
address to have an A record, or will an MX suffice;  I know lots of people
that send as "[email protected]" where is an MX only...  I'm just
not familiar enough with sendmail rules to know how it works ;-)

If Cyberpromo were really trying to *cough* help, they would set all the
reply-to's in the spams to "[email protected]"  ;-)

yeah... right...

      D. Taner Halicioglu                     [email protected]
  Programmer/Engineer/Sysadmin            Internet Systems, Inc.
    Voice: +1 408 543 0313                 Fax: +1 408 541 9878
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