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Re: Extreme times call for extreme measures?

2004-10-06 14:31:29
Jon Bertrand wrote:

One of the measures is to block direct-MX connections from dsl, cable
and dial-up networks.  In your case, the reverse DNS entry for your
server's IP address is "h-66-166-42-108.dnvtco56.covad.net".  We block
all connections from ".covad.net".  This does not effect the normal
Covad mail servers.

  3) Change the DNS - wow, is this a common thing to do?

So, is this a common thing? Is this idea gaining ground?

Not sure about common ground, as I just cover my neck if the woods. But I
certainly do the same. Your PTR would be rejected at my server, with the
following exceptions:

1): You are an authenticated user (SASL/DRAC).

2): You are whitelisted (local policy).

3): You announced yourself with a HELO name, not indicate of a dynamic PTR
name (I use a custom regex for that), and the A record lookup of your HELO
includes your IP, of course. :) My rationale is, that if you bothered to get
a domain name for your IP address, then both these are true: your IP address
is likely static (or "static-ish"), and you are not an "owned" zombie. The
latter could actually still be the case, but I have yet to see a spammer
register a domain name for a zombie IP address (or do I?)

You may, indeed, change your PTR; or get your friendly ISP to change it for
you. :) That would certainly help you.

- Mark

        System Administrator Asarian-host.org

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