[Mailman-Users] Limited posting

[J C Lawrence]

On Tue, 02 Oct 2001 12:08:51 -0700 
arandall  <Amanda> wrote:
> Jim Kutter wrote:

>> That brings me to another question - what's an accurate method of
>> counting the number of bounces? I was grepping the bounce log and
>> counting the number of bounces for my newsletter. That will only
>> work however if I wipe the bounce log every few days - and even
>> then I won't get a very accurate count... Also - as far as stats
>> go, in the smtp log, is that a fair count for how many messages
>> really got sent?

> Hmm. This (the bounce-counting) is one of the reasons I ended up
> ripping Mailman into many component pieces and then ended up
> custom-writing something completely different for the newsletters
> themselves. If you find a clean and accurate way to do that using
> Mailman, let me know. :-)

Without using VERP its actually impossible. 

  -- Mailman attempts to determine subscriber address by parsing the
  bounce.  This is cheaper than VERP, but is also error prone.

  -- There is not a 1:1 mapping between bounce messages and sent
  messages.  A single send message may generate multiple bounce
  messages from intermediate MTA's if they are unable to deliver it
  quickly.  Further, given a history of sending mail, you may
  receive multiple bounce messages all from previous mailings (prior
  to your last) with no way to reliably distinguish them from
  bounces in response to your current mailing.

Bounce counting under Mailman does give numbers, but they are
unreliable and shouldn't be used for anything other than SWAGs.  To
get "real" bounce counts you'd not only have to use VERP across your
subscriber base, but also VERP across your mailings so that every
message you send not only has a unique return address for each
subscriber, but also has a unique and trackable return address for
each message sent to each subscriber.

This is doable, but is not entirely trivial.  Its quite outside of
Mailman's base area of interest.

-- 
J C Lawrence
---------(*)                Satan, oscillate my metallic sonatas.
claw at kanga.nu               He lived as a devil, eh?
http://www.kanga.nu/~claw/  Evil is a name of a foeman, as I live.