Mail delivery of macports-changes disabled for Gmail users

[Rainer Müller]

Hello,

if you are using Gmail or a Google hosted mail service for your domain,
your subscription to the macports-changes mailing list was likely
disabled on 2019-02-22 by mailman due to "excessive or fatal bounces".

If you still want to receive the mailing list, but are currently not
getting the emails, you have to take manual action. Please follow the
link below to the mailman options. After logging in, check that the
option "Mail delivery" is Enabled for your account.

https://lists.macports.org/mailman/options/macports-changes


The technical cause of this was an email being rejected by Google due to
a strict DMARC policy for the From address. The way Google handled this
was correct as this mail was in fact not originating from a source
whitelisted by the domain owner of the From address.

Although we configured all our lists on mailman exactly for this reason
with dmarc_moderation_action="Munge From" [1], we now discovered that
this setting is an action that only applies to mails going through the
moderation queue. However, as posting to macports-changes is meant to be
restricted, legitimate mails are pre-approved. As we have learned now,
skipping the moderation unfortunately also skips the DMARC munging that
was supposed to prevent such bounces.

In order to prevent this from happening again, I would like to no longer
sent mails with the author's address as From, but use a generic From
address and merely the author to CC. Unless someone else comes up with a
better idea, I will look into applying this in the next days.

Rainer

[1] https://www.gnu.org/software/mailman/mailman-admin/sender-filters.html