Author: Dave C. Date: To: Toralf Lund CC: Exim Mailing List Subject: Re: [Exim] Frozen delivery failure notifications (invalid sender)
- again
On Wed, 25 Sep 2002, Toralf Lund wrote:
> > On Tue, 24 Sep 2002, Toralf Lund wrote:
> >
> > > What if I set up an account or alias so that the address would be
> > valid,
> > > and add auto reply, "vacation" style (with a long or possibly infinite
> > > reply interval) with a message that would explain it all, and encourage
> > > people to block messages from this address?
> >
> > Where would the vacation reply be sent ?
> > It would go to an address which is failing - that is why your existing
> > message gets frozen.
> Not quite. The message is a bounce to the sender address the abuser is
> using (users002@??? in my case), which is not valid, and the
> message is therefore frozen. Also, it is sent because the target address
And the best solution is, as stated previously, at *SMTP* session time,
after the
RCPT TO: <users002@???>
that the bouncing host is issuing, respond with a 5xx code, eg
550 Invalid recipient
That way the messages dont ever enter your server. If you cant or wont
do this, then you will get the frozen double-bounces stuck on your
server.
You can use ignore_errmsg_errors, if you want, or clear them by hand.
> of the original message, i.e. the spam, isn't valid, either. The sender of
> the bounce, however, ought to be valid - it is typically
> postmaster@<target domain for spam>.
Ack! No! Bounces should be sent with a NULL sender (Eg, <>), to avoid
loops. All proper MTA's implement this correctly, although a few crappy
commercial ones do it wrong.
> But like someone else said, perhaps the postmaster in question wouldn't
> want additional noise from me about this.
