On Wed, 10 Oct 2007, Graeme Fowler wrote:

| Given that you've explained three times now what you're doing, and I
| still can't see where you're generating your blacklist, I can see a flaw
| here. If a user sends a message to, for example, a person the BBC with a
| sender address of [EMAIL PROTECTED], and the person at the BBC
| responds, will that mean the BBC's outbound MX farm will end up
| blacklisted?

Hi,

As you know, Alun's talking about SMTP connections to hosts which are not 
supposed to receive external mail.  My reading is there are two cases:

- Where the recipient email address corresponds to some host 
  under *.aber.ac.uk, then the attempt will simply be rejected cleanly 
  with no further penalty.

- Only where the recipient address corresponds to something external 
  (ie. a relay attempt) will the connecting IP be added to blacklist, 
  to be used by the main MXs etc.

The former case is an innocent mistake, whereas the latter is normally 
malicious.

In my view the idea of such a responder is a good idea.  Sites who don't 
have a linux firewall (or who don't wish to run such stuff on their linux 
firewall itself) could do similar with a some sort of policy-based network 
routing rules and a dedicated responder machine.

-- 
## List details at http://lists.exim.org/mailman/listinfo/exim-users 
## Exim details at http://www.exim.org/
## Please use the Wiki with this list - http://wiki.exim.org/

Reply via email to