Re: Which Spam Block List to use for a network?
On Wed, Jun 23, 2004 at 08:32:17AM +0200, Adrian 'Dagurashibanipal' von Bidder wrote:
> On Wednesday 23 June 2004 03.27, Blu wrote:
> > > > In my server, my policy is to reject mail from hosts which are
> > > > blocking me.
> > [...] blocking mail which cannot be
> > answered blocks a lot of forged sender spam too, something like 80%
> > here, being conservative.
> You did say two different things here.
> I block mail which can't be answered, too, by requiring the send domains
> to exist. After an upgrade to postfix 2.1 I will consider verifying the
> user part of sender addresses, too, if greylisting doesn't get the spam
> down far enough.
Well, if a host blocks mail from me, mail from that host is in fact
unanswerable mail. It is just a subset of mail which can't be answered.
> I've never had my mail rejected by some mailserver, yet, but I don't
> think I would just block mail from mailservers blocking me - when my
> block produces false positives, I'm glad if people tell me (the 550
> message tells them how to contact me by email without being blocked.)
> So I like to extend the same courtsy to the operator of the other box.
> As was said in this thread by somebody, it's all about enabling
> communication, and not about making it impossible. And blocking spam
> just keeps email a useful medium.
My 550 tells people that it is HIS host which is blocking mail from mine
and that I will accept mail from them as soon they stop blocking me.
I run a number of public service servers and in the past, from the
perspective of an user of a server which blocks mail from mine, the
mails were being blackholed at my host. They never got an answer or even
a bounce. Now, at least they know what is going on and know that the
problem is their side, not mine.
Finally, I keep postmaster always open, a thing that a lot of this happy
blocking servers does not.