Quoting spiralofhope (spiralofh...@spiralofhope.com): > If an email address successfully receives a few emails but then gets > automatically unsubscribed later, could this be why?
That would be a possible reason (but not on this mailing list since the implementation of DMARC migitation a bit over a year ago). GNU Mailman records the fact of it incrementing a subscriber's 'bounce score' (and eventually disabling subscription delivery, and then as a later stage unsubscribing, if bounce score remains persistently[0] high) into log file /var/log/mailman/bounce, which is world-readable for command-line users on the Mailman server. However, that log doesn't include the reason for the 'bounce', in part because Mailman is a bit of a dunce about such things[1], so researching the exact reason then requires also that a site admin look through the logs for the MTA associated with Mailman. > (Or would problematic settings means that no emails would ever be > received in the first place?) Your question's a bit vague. (a) If Mailman cannot reach a would-be subscriber by mail, then the person will be, by definition, unable to complete the three-way handshake process required to subscribe. (b) As a reminder, the typical scenario you are discussing (as quoted near the top of this post) involves adverse consequences _not_ primarily to the subscriber whose domain has an aggressive DMARC policy, but rather some other subscribers. Illustration: Imagine two subscribers to Dng; call them Gmail User and Yahoo User. One day, Yahoo User posts a valid posting to a Dng thread. Mailman receives it, and attempts to re-mail copies out through its local MTA to each Dng subscriber of record, including Gmail User. Because GMail enforces at the time of receipt the declared DMARC policies of what is asserted to be the source domain of an arriving mail, and because yahoo.com has an r=reject DMARC policy and its declared roster of authorised origins for yahoo.com mail doesn't include Dng's MTA host, Gmail 55x-rejects Gmail User's copy. He/she never sees Yahoo User's posting. Worse, Mailman takes note of the 55x rejetion, and increments GMail User's bounce score, in effect sanctioning Gmail User for Yahoo User's domain's (IMO) problem-causing antiforgery procedures. After a few such incidents, Gmail User gets his/her delivery disabled and eventually unsubscribed. Back in the latter half of 2018, this happened a few times and I observed people complaining to Golinux, who was in fact not in a position to read the MTA logs, hence they were complaining to the wrong party and basically shouting at the clouds. (IMO, it really didn't help that a whole lot of folks here are desktop computer users afflicted with what I call helpdesk mentality, where one imagines problems get solved by people complaining rather than doing relevant analysis.) [0] There's some logic to expire out a user's bounce score after something like a month. [1] E.g. Mailman doesn't even try to parse 45x and 55x DSNs the outbound MTA receives when the MTA attempts to deliver a particular subscriber's copy of a mailing list posting. Mailman just notes in its log that a 'bounce' event occurred and increments the user's bounce score, irrespective of what caused the non-acceptance. _______________________________________________ Dng mailing list Dng@lists.dyne.org https://mailinglists.dyne.org/cgi-bin/mailman/listinfo/dng
