Atrivo/Intercage: Now Only 1 Upstream

David Schwartz davids at
Wed Sep 17 14:25:51 CDT 2008

> I occasionally get in to an argument with a customer who is trying to
> get mail from someone after a spam run came out of a google mail server
> and landed it on a DNSBL. The argument presented to me always boils down
> to "Google could never do anything wrong" or "Google is too big to do
> anything wrong" and I should immediately stop recommending any DNSBL
> that would dare to block Google.
> ~Seth

A more rational version of this argument would be that blocking Google's
mail servers will obviously have large amounts of collatarel damage. Any
DNSBL that blocks Google's mail servers, other than perhaps in sufficiently
serious situations to justify this level of collatarel damage, shouldn't be

You should provide a way for customers to opt out of your blacklists. Many
people are perfectly happy to run their own spam filtering software and
retain the capability to skim (or analyze) their spam.

If you provide a way for your customer to do this, point them to it. If not,
that is a failing on your part. (Though of course it's always possible you
have cost/benefit arguments that justify not providing that service.)

Some people would really like email to be as reliable as possible, even if
that means they have to wade through a lot of spam. At least this gives them
ability to whitelist sources that are important to them personally.

David Schwartz
<davids at>

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