Philip Hazel writes:
>
[...]
>
> What I'd like to ask for views on is whether this new style should be
> the default or not. It would be an incompatible change, but would affect
> only those sites that had set one of the rejection options. I have a
> feeling it will be the more useful setting and I would like to make it
> the default.
However, note in particular that it is incompatible in the following way.
Back in August, Nigel asked for
Nigel> 2. Ability to put exim into refuse mode.
Nigel> This can be done by killing the SMTP listeners, but the ability to
Nigel> tell the daemon to either refuse connections, or to give them a status
Nigel> that tells them to push off!
and Philip suggested
Philip> sender_host_reject = * already exists for this purpose.
With the new suggested default this means "reject all incoming messages" (an
extreme isolationist attitude!) rather than "refuse all incoming connections".
MTAs, including Exim, don't take 4xx or 5xx errors in the initial or HELO
responses to refer to any particular message, because none has yet been
mentioned. [Indeed, it isn't clear what the difference between a 4xx and 5xx
is at this stage: maybe 5xx is a hint that you should wait longer before
attempting another connection, but in practice MTAs, again including Exim,
do not distinguish them.]
Chris Thompson Cambridge University Computing Service,
Email: cet1@??? New Museums Site, Cambridge CB2 3QG,
Phone: +44 1223 334715 United Kingdom.
