[Mailman-Users] shunting

[Mark Sapiro]

Imre Gergely wrote:
>
>after solving this, i figured, on my lists nobody ever uses digest mode, so i
>just disabled it on all lists, then deleted digest.mbox. i guess with this
>setup, if a list gets a broken message which mailman can't handle, it will be
>shunted and that's it, the rest of the list and messages won't be affected,
>am i right?


Yes.


>and what happens with the archiving? the message gets archived before, or
>after a successful delivery? in another words, is there a chance that a
>broken message will be archived?


Most of these problems that stop a list involve the digest.mbox. What
happens is digest.mbox contains a message that throws an exception in
Scrubber. When digest.mbox reaches digest_size_threshold, we try to
create both a MIME and plain text digest and finally generate the
recipient list for each digest and queue it to be sent.

If Scrubber (which is invoked to flatten the message for the plain
digest) throws an exception in this process, pre Mailman 2.1.7 this
caused the message to be shunted and the list would effectively stop
as this all occurs before archiving and regular delivery, and the
whole thing repeats with each new message.

By setting the list digestable to No, digest processing is skipped so
the problem doesn't occur.

In Mailman 2.1.7 and later, all exceptions, even unanticipated ones, in
the send_digests process are caught and logged as an error, so list
processing other than sending of digests doesn't stop.

As far as archiving is concerned, Scrubber will also be invoked on the
broken message in order to flatten it for the archive. It will throw
some exception which will be caught in ArchRunner and the message will
be shunted, but in this case, it only affects the one message and only
the archive, not delivery.

-- 
Mark Sapiro <msapiro at value.net>       The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan