responding to DMARC breakage

Sun Apr 13 01:34:22 UTC 2014

On Sat, Apr 12, 2014 at 9:12 AM, Miles Fidelman
<mfidelman at meetinghouse.net> wrote:
> - Yahoo (operationally) and the DMARC authors are intentionally
> un-responsive (as are hotmail, comcast, a few others; gmail, I note is not
> bouncing mail)
>
> How do we respond as operators, beyond late-night, ad-hoc patches to list
> software, that only partially resolve the problem?

In the face of intentional unresponsiveness:  blacklisting.

Start contacting  Yahoo.com subscribers and explain the situation to
these users,  and inform the users that,  for the time being:
yahoo.com e-mail addresses can no longer participate in the mailing
lists, because of Yahoo's new policy:   And make some suggestions of
good alternatives to using Yahoo mail.

Then use mail filters to block messages to mailing  list addresses
with From: header yahoo.com  (which cause the problem),  next
suspend subscriptions for   @yahoo.com users,   and configure mailing
list software so that new @yahoo.com based e-mail addresses cannot
subscribe or post to the lists.

--
-JH