Autor: Alan J. Flavell Data: Para: Exim users list Asunto: Re: [exim] Anti SPAM Exim configuration
On Wed, 15 Dec 2004, Tony Finch wrote:
> I've found that defer_ok is pretty much required for callouts to be
> usable.
If you're doing callouts as a matter of course, then that's certainly
the case, I agree.
However, with the selective strategy that we're using, changing to
defer_ok would defeat the effectiveness of many of the callouts which
are successfully fending-off spam.
> Without it you end up losing too much desirable email from
> incompetently configured web servers. The disadvantage of this is
> that it's often incompetent web servers which are the sources of
> spam
Just so. Which I'd say is where a selective strategy can pay off.
> So perhaps this kind of callout
> failure would be worth an extra SpamAssassin point,
Yes, I've no argument against that option.
> but it causes too much trouble to propagate the result into an SMTP
> error.
As I say: that depends on how one is using callouts. I'm not saying
you haven't made a defensible choice[1]: I'm just saying there are
other viable approaches, and each has their good and bad points.
No offence intended - all the best
[1] however, there are some who certainly -will- argue that you have
no right to consume third-party resources in that way, merely on the
excuse that some third-parties' domains are being faked by spammers.