On Thu, 2010-04-22 at 20:54 -0400, Chris Meadors wrote:
> On 4/22/2010 8:37 PM, Ted Cooper wrote:
>
> > Unfortunately, it's very hard to tell the difference between a
> > callout and a bounce at rcpt time.
>
> If you do still get a lot of backscatter (I've not seen much these days,
> admins do seem to be getting a clue), you should look into BATV signing
> your outgoing messages. Then it is very easy to differentiate between a
> callout/valid bounce, and forged backscatter.
Unfortunately, I can't do BATV in all these cases as I am not always
responsible for the outbound queue.
Now days I usually only run the inbound mail filtering. The server in
question here is one of the last ones standing from the way I used to
run things. At some point it became impractical to run so many separate
filtering servers, each with its own setup. The outbound email is now
managed in house.
I could certainly encourage the in house setup to be changed, but it
can't be guaranteed for all and so I'm stuck without it.
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