On Mon, 5 Feb 2001 15:37:56 -0500 (EST), woods@??? (Greg A.
Woods@??? (Greg A. Woods)) wrote:
>[ On Monday, February 5, 2001 at 20:27:45 (+0100), Marc Haber wrote: ]
>> Nevertheless, customers demand it. And for some other customers, we
>> are only mailgate because the customers are clueful enough to not let
>> an Exchange talk directly to the outside world.
>
>"customers?"
>
>If you're offering your downstream IP access customers a secondary MX
>server, then you're getting everything you "deserve" :-)
Yes. But I want to lessen the pain ;)
>"Doctor, Doctor! ... " "Don't do that!" :-)
People demand it. So we do it.
>Now on the othe hand if you're blocking direct connectivity to a
>customer's mailer in order to protect it from the "Big Bad
>Internet(tm)", or the customer is doing that of their own accord, then
>you are, for *all* intents and purposes the primary MX and you should
>make sure your mailer is advertised as such in the DNS
Of course. I didn't start in this business yesterday. If the
customer's mail server isn't directly reachable, then the only MX
listed in the DNS are ours.
>and that it is
>configured properly to deal with this scenario.
Define "configured properly". We have adopted the hubbed_hosts setup
from the FAQ 0301(B), but we don't have (read: don't want to have) a
list of valid addresses on our downstream hosts. So, we deliver to our
downstream, and if that machine decides to refuse an address, fine.
But I don't really want to see that kind of bounce - it should go to
the sender, but not to our postmaster mailbox.
>You should never ever
>advertise a primary MX that's unreachable from the Internet (it might
>work, but it's enormously the wrong way to do things).
I know. Do I really make the impression of being _that_ stupid?
>that it's quite easy to configure your mailer to ensure that all mail
>accepted for your customers' domains is forwarded directly to your
>customers' mailers, regardless of whether it's a bounce or not. If your
>customers' mailers are returning bounces to you in that scenario then
>*they* have a configuration error and you can stomp on their e-mail
>service (i.e. cut it right off) until they agree to fix their
>configuration errors, software, whatever.
We are talking about different things here.
Let's see:
|customer.example.com IN MX 10 mx.we.example.com
mx.we.example.com has "errors_copy = *@* postmaster" and a
hubbed_hosts saying
|*.customer.example.com: mx.customer.example.com bydns_a
Mail comes in for the internet for foobar@??? from
sender@???. mx.we.example.com accepts mail,
spools it, delivers it to mx.customer.example.com.
mx.customer.example.com says "500 unknown local part foobar in
<foobar@???>. mx.we.example.com generates bounce to
sender@???, copies to
postmaster@???. This is the scenario I am talking about.
>Of course you could simply charge your customers appropriately for
>handling their <postmaster> mailbox too.
Yes, they are getting charged for that anyway. But I am looking for a
way to hide bounces for causes that I know that I am not the cause
for.
Greetings
Marc
--
-------------------------------------- !! No courtesy copies, please !! -----
Marc Haber | " Questions are the | Mailadresse im Header
Karlsruhe, Germany | Beginning of Wisdom " | Fon: *49 721 966 32 15
Nordisch by Nature | Lt. Worf, TNG "Rightful Heir" | Fax: *49 721 966 31 29
