Re: Access DB question

* Per Hedeland wrote:
In article <fb47h5$af7$1@xxxxxxxxxxxxxxxxxxxx> NPG
<nathan@xxxxxxxxxxxxxxxx> writes:
* Per Hedeland wrote:
No. Bouncing it is wrong. Dropping it is wrong. Rejecting it in the SMTP
session where you (i.e. the MX) receive it is right. Which means that
you need to know whether the primary will reject it without asking at
that point.
I see, so
Bouncing it is wrong because I have already taken responsibility for it.

No, bouncing it is wrong because that can be backscatter. If it wasn't
for the &%@)(%)@#?* spammers, it would be perfectly fine, and it was
what every mail system on the planet did before the age of spam. It is
also perfectly fine as far as the RFCs are concerned - one point where
they differ from reality.


So it is a case of the bad guys ruining a good thing for everyone due to
their misuse of it.

Dropping it is wrong because there is a chance that it might have been a
legitimate ( but misaddressed ) message.

Yes. Or maybe your spam filters did a false positive - your "fault" of
course, but without the blackholing MX, the legitimate sender would have
received a bounce to that effect, and could try changing the content
and/or tell you to fix your filters and/or use some other means of
communication.


Correct

I see, the receiver should Accept it, and then deliver it, or should
reject it.

In the age of spam, yes.

Co-located (virtual) server isn't economically feasible, or what?

Basically, yes.
We are a small company, not a backbone provider. :-)

Actually, I think such services are pretty cheap these days as long as
your processing and bandwidth needs are moderate.


I'll definitely look around. Recommendations are welcome.

Well, discussion can be useful even if no (participant) minds are
changed. I would really be interested in hearing a good motivation (or
*any* motivation) for having a backup MX of the form you expect, since I
can't see that it buys you anything other than a significantly increased
risk of losing mail when your primary is down.
All we would lose is what the primary wouldn't accept anyway.

But that is obviously not an argument for having a backup, only a claim
that it wouldn't actually cause any harm. And that claim is even
invalid, because:

Senders would lose their bounces if their mail went through the backup
MX. ( Their typo, their problem. )

No, you should assume that the sender and recipient both have an
interest in reliable delivery of legitimate mail. The lost mail might
have been something very important for one of your users to receive -
after a while he gets p*ssed off at the sender for not sending it and
calls him up to complain - at which point the sender claims that he
*did* send it, and might even be able to produce log entries showing
your MX accepting it. Now who will your user be p*ssed off at?


Point Scored.

Of course I will probably
try to shoot down your arguments, but you're free to not change your
mind because of that.:-)
:-)

I'm still waiting for any actual pro arguments.:-)


You are not going to get any.
Our DNS has spoken :-)

--Per Hedeland
per@xxxxxxxxxxxx
.

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