Author: Tim Jackson Date: To: exim-users Subject: Re: [Exim] Ignoring bounce messages to alias - How?
Hi David, on Fri, 06 Feb 2004 13:59:00 +0000 you wrote:
> On Fri, 2004-02-06 at 13:49 +0000, Tim Jackson wrote:
> > The main one that I see is that if someone sends mail from elsewhere
> > using an address handled by your server, and that mail causes a
> > bounce, the bounce will be lost even though it's "legit".
> That's actually trivial to fix by offering SMTP-AUTH.
Sure, as long as:
a) you do indeed offer SMTP AUTH
b) all your users know that you offer it, know how to use it and know that
their mail will be unreliable if they don't. They also know how to
identify and work around transparent SMTP proxies, and you've opened
up a separate port on your relay to help them do that.
c) your users are never in a situation where they can't use it. E.g. in
a situation where they can only do outbound SMTP to a given machine, or
using a device that doesn't support it (the SMTP AUTH support in some
software, especially on some mobile devices, is limited or
non-existent)
[I'm trying to be pragmatic here: in an ideal world, we probably could
just say "use SMTP AUTH" and be done with it]
On a university-size user base (even in Aberystwyth), I suspect this may
be non-trivial to achieve. Although you could of course again decide as a
matter of policy that the limited number of problems caused by the above
cases are outweighed by the benefits.
Offering webmail is another solution to limit the above problems, and many
people seem to prefer using it, so that's another possible "solution".