Was ist VERP? Like I said, I've moved away from Mailman for my announce-only newsletter type lists, so it won't really help Mailman users to hear this, but just in case anyone's interested.... With regards to bounce numbers, we've developed a "pitchfork" approach (it has several prongs with which to attack the problem).
One, the mail-send script keeps two logs: one that notes the address of each message that was accepted for delivery by the local MTA, and one that notes the address of each message that was not accepted, for any reason (and in the case where there's an error code to log, it logs that too). So we know which ones were rejected right out of the gate. Two, if a message comes back to the originating *sender* address as an RFC822 type bounce message (gods, but those are rare these days) or as a message with some other regular expression that can reasonably be identified as a notification that mail was not delivered for whatever reason, the email address that appears in that message (top, bottom, wherever) is saved to another file for digestion at a point in the future. (Messages that don't fit these criteria and are not obviously administrative requests get dumped elsewhere for a human to eyeball.) Three, the file that contains those bounce addresses is masticated. If an address appears more than once, the extras are discarded; then those users are added to the master bounce file (if an entry does not exist for that email address) or their count is incremented by 1 (if an entry does exist). We can pretty much get away with discarding extras because the mailings go out a minimum of forty-eight hours apart - the same time frame set in our local qmail for returning a fatal delivery message. This approach wouldn't be quite as clean on a list that has more traffic. Anyway, that gives us the number of addresses to which mail was apparently bounced. It also gives us the ability to export a list every X days of email addresses which have bounced Y times (currently, about every five weeks for users bounced 8 or more times), so that we can then set a flag in the (full-fledged multi-purpose) user database that basically makes that user's subscription inactive. Is it 100% accurate? No; in fact I'm going bugnuts right now trying to find the hoser who decided that a message from "nobody@" whatever-dot-org with a blank subject that says "Sorry your message couldn't be delivered. You probably have the wrong address." (Literally.) without a forward of the original mail, an indication of who the intended recipient was, nothing useful in the headers... Without unsubscribing every single person at whatever-dot-org, I will probably never find out which address is bad. Gerf - I hate a surprising number of sysadmins out there... but anyway, I'd estimate we're reporting stats that are in the 85-90% accurate range. That's good enough to track trends and make the marketing weenies happy. One note about the suggestion of using a marketing-tracking approach of putting an image in your mail that lives on the website ... this will definitely skew your stats because of the significant number of people who don't have HTML-enabled mail clients. We actually run two lists for the newsletter - a text-based and an html-based - to accomodate, for example: older AOL clients, AOL users who have set preferences to block mail with embedded images, a significant number of people using Novell GroupWise (as the admin doesn't have to allow the components that provide a means of reading HTML-based mail, and frequently doesn't even know it can be done), older versions of Eudora, Claris, and other lightweight clients which are very common with hospitals and schools, and apparently some people who installed some funky "security patch" (ha) to Outlook (OE? I forget which). Nothing is as easy as it used to be... =) Amanda J C Lawrence wrote: > 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. > [EMAIL PROTECTED] He lived as a devil, eh? > http://www.kanga.nu/~claw/ Evil is a name of a foeman, as I live. ------------------------------------------------------ Mailman-Users maillist - [EMAIL PROTECTED] http://mail.python.org/mailman/listinfo/mailman-users
