Re: Which Spam Block List to use for a network?
On Wed, 23 Jun 2004 18:23, Blu <firstname.lastname@example.org> wrote:
> Well yes. Maybe I oversimplified. What I do is a callback to the MX of
> the envelope sender to see if it accepts mail to him/her. If not, the
> mail is rejected with an explicative 550.
You aren't the only one who does that. I have found one other person who does
that and who happens to have their mail server in an address range that's
black-listed. So when I sent mail to them their mail server made a call-back
to mine, my server rejected that and their mail server then generated a 55x
code that tried to summarise the code from mine. Then my mail server took
that and made it into a bounce message.
The resulting message was something that I could not decipher even though I
have 10 years of experience running Internet mail servers! All I could do
was post a message to a mailing list I knew the person was subscribed to and
inform them that their server was borked in some unknown way.
What would the average Internet user do in such a situation?
The typical 55x message about a DNSBL rejection is clear enough that most
people can get some idea of what to do (IE phone the person, use a different
mail server, etc).
The call-back idea may be good if you have a domain totally full of clueless
morons who only receive mail from skilled administrators who have experience
in dealing with call-back systems. But if you have average people exchanging
email with other average people (the common case) then it will make things
worse not better.
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