[Mailman-Users] Lists stop working

[Mark Sapiro]

Stephen J. Turnbull wrote:
>
>Fairly early in message processing, Mailman logs to either logs/post
>(showing that the post was accepted) or to logs/vette (indicating that
>the post was held or rejected, and why).


One minor point here. The post log entry is not written until the
message is delivered by SMTPDirect.


>When the post is delivered,
>there will be an entry in logs/smtp for each batch of deliveries
>(usually one per remote host, or one per user if personalization or
>VERP is being used).


Actually, if nothing goes wrong, there will be only one entry in the
smtp log covering all deliveries. If things go wrong there will be
perhaps multiple entries in both smtp and smtp-failure logs.


In spite of the minor corrections above, Stephen's advice is excellent.

To elaborate on Rolf's question about how Mailman processes a post.
Assuming a standard configuration where the MTA delivers to the
mail/mailman wrapper.

1) The MTA pipes the message to the wrapper which passes it to the
scripts/post script which in turn places it in the qfiles/in queue.
Nothing is logged in Mailman, but the MTA normally logs the delivery.

2) IncomingRunner picks up the queue entry from qfiles/in and passes it
through a pipeline of handlers (GLOBAL_PIPELINE - defined in
Defaults.py, possibly modified in mm_cfg.py - unless the list defines
a pipeline attribute to override it). The initial handlers check
header_filter_rules, look for an Approved: header and possibly
generate an autoresponse. The next set of handlers checks for
moderation and other holds and does content filtering, emergency
moderation and topic flagging. Any of these handlers can raise
exceptions to request IncomingRunner to discard, reject or hold the
message at that point. Discards and holds are logged in the vette log.
Rejects are not logged, but result in a reject message to the poster.
Any other exceptions cause the message to be moved to qfiles/shunt and
the exception is logged in the error log.

The next set of handlers determines the recipient addresses and
possibly removes and/or modifies some message headers.

Then handlers add the message to lists/<listname>/digest.mbox if the
list is digestable (and possibly trigger a digest on size), add the
message to qfiles/archive for processing by ArchRunner, possibly add
the message to qfiles/news for processing by NewsRunner, update the
list's last_post_time, send an acknowledgement to the poster if
requested, and add the message to qfiles/out for processing by
OutgoingRunner.

3) ArchRunner picks up the queue entry from qfiles/archive and adds it
the the list's archive.

4)NewsRunner picks up the queue entry from qfiles/news and delivers it
to Usenet.

5)OutgoingRunner picks up the queue entry from qfiles/out and calls
SMTPDirect to deliver it to the outgoing MTA via SMTP. SMTPDirect logs
posts to the post log and logs a bit more detail to the smtp log. Any
SMTP failures are logged to the smtp-failure log and treated as
bounces or queued for retry as appropriate.

6) Any unanticipated exceptions in any of the runners cause the message
to be moved to qfiles/shunt and the exception to be logged in the
error log.

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