Re: draft-ietf-usefor-usepro-02

["Charles Lindsey" <chl@xxxxxxxxxxxxxxxx>]

In <41C2AA2D.2F14@xxxxxxxxxxxxxxxxx> Frank Ellermann <nobody@xxxxxxxxxxxxxxxxx> writes:

>Charles Lindsey wrote:

>> The best means for preventing loops is to ensure that
>> Message-IDs are propagated correctly.

>Unfortunately that's not the case.  Loops cause two kinds of
>problems:  dupes and nopes.  Saving the Message-ID is only a
>part of a possible solution.  In your examples it would be
>better to have a "do NOT reimport to Usenet" flag instead of
>the Message-ID.

I don't think there is any reason to forbid "reimport to Usenet" as such
(for example, it may come back into Usenet in a different group and with a
different message-id).  What is important is to deal with it properly when
it comes back to the place where it was gatewayed out of usenet in the
first place.

>Here's a scenario where your strategy fails miserably:

>you -> A - B - C -> me
>       |   |
>       a   b
>       |   |
>       other

>I never see some of your articles in group ABC.test, they do
>not exist on server C (= "nope").  A, B, C, the gateways a
>and b, and the other net followed your strategy, they kept
>the Message-ID, but it didn't work as expected.

But you have not explained to me why it never got to server C, or indeed
exactly what a "nope" is. Please could you describe your scenario in more
detail.


>> we need a last-ditch backup, for use only in these really
>> nasty situations.

>No, the last ditch backup is "do not gateway if you don't know
>what you are doing".

Have you ever met a gateway admin who would admit that he "didn't know
what he was doing" :-). No, I think it is up to admins to decide when
the place he is supposed to be gatewaying to is just too bizarre that he
should give up the attempt. So long as it doesn't cause loops and so long
as the people on the other side of his gateway can accept what he sends,
he should be allowed to try.


>"Save the Message-ID somehow, maybe in the body" is completely
>misleading, because it's simply not good enough.

Well we are not actually recommending that in our draft. However, I would
not preclude that there might be some sufficiently bizarre "other medium"
where such a thing made good sense.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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