initial alias file

Leland J. Steinke steinkel at PA.NET
Thu Jan 16 16:52:14 GMT 2003


Patterson S.R. wrote:

>
> If that all sounds exceedingly complex, then I'd just live with the
> problem if I were you!
>

It was really quite easy for us to do with postfix running on the border
email scanning gateways.  We push a hash of valid email addresses out to
the border every hour.  Postfix verifies recipient addresses against
this hash as it becomes aware of them.  It tarpits invalid recipients
(by a couple of seconds), so we have some protection against dictionary
attacks.

When we initially tried to implement border mail gateways for filtering,
without the valid email hash, the number of messages bouncing back and
forth between our real mail server and the gateways caused them all to
melt down.  It was not at all pretty.

I suppose I should sign the guest book and give a rough average of
emails processed!


Leland



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