Andreas Barth writes:
Looking into details, his mail provider sent out lots of auto aways notices marked with Auto-Submitted: auto-replied (vacation)
Should we not exclude these as being counted as bounce?
First of all, until recently Mailman 3 wasn't doing any bounce processing at all. Depending on your version, it's possible that Mailman had nothing to do with it.
Now, are these going to the bounce address, or to the list? If they're going to the bounce address, I doubt they're being recognized as standard delivery status notifications. I think they're probably still counted as bounces if sent to a LIST-bounces address, but they should also be sent to the list owner as "unrecognized bounces". This decision isn't something Mailman should be doing because it depends on context and guessing what the subscriber wants. Really, this is an owner problem, not a Mailman problem.
On the other hand, if they are going to the list itself, I don't think we treat those as bounces at all.
It's not obvious what *we* should do. If Mailman continues sending posts to the user, it can fill his or her mailbox with mail that is in many cases available in archives. Not a good idea. In fact, typically the reason vacationers get unsubscribed is because their mailboxes fill up, and they generate real bounces. Or a moderator got tired of vacation messages to the list, and nuked the subscription. Are you sure one of those is not what happened here?
I don't understand how the user managed to get automatically unsubscribed unless you have aggressive bounce settings on the mailing list(s) or they were gone for quite a while. What should happen is after the first few bounces they will be disabled, and then checks for reactivation will be sent once a day or so. It should take at least two weeks, and often longer, to unsubscribe a user. If you live where people habitually take month-long vacations, you should change your settings to account for that.
Finally, if the user doesn't want to get unsubscribed while they're on vacation, they can set themselves to no-mail. They should also be able to resubscribe themselves; deleting a subscription for excessive bouncing doesn't delete the user's login account.
Steve