> Date: Saturday, June 16, 2018 05:25:05 -0500 > From: Johnny Hughes via CentOS <centos at centos.org> > > On 06/15/2018 05:18 PM, Richard wrote: >> >> >> I believe this is a DMARC issue. Yahoo, among other places, has set >> their dmarc records to p=reject: >> >> dig +short txt _dmarc.yahoo.com >> "v=DMARC1; p=reject; pct=100; rua=mailto:dmarc_y_rua at yahoo.com;" >> >> So, if your mail hosting provider enforces dmarc,(gmail does) and >> you get mail from a list that doesn't rewrite the headers, and >> people from places like yahoo post to the list, you'll likely get >> some form of warning about being being kicked off the mailing list >> every now and then. The frequency depends on how often people from >> p=reject places post, and what the settings are for bounce >> handling of the mailing list in question. >> >> I believe that the current version of mailman can be configured to >> do the necessary header rewrites. Some lists I'm on only do the >> rewrites for headers of posts coming from p=reject sites (much >> less annoying than having them all rewritten). > > This is indeed what happened. An email from yahoo.com.uk caused > gmail to reject all the mails sent by that user because of the > yahoo DMARC settings. > > We have now set the mailing list to rewrite headers. That also has > set the From: of the email to the Mailing list and not the Original > Author. The author is moved to the CC: block and you can still > easily see who sent it and my email client (thunderbird) still does > things the same way (reply to list sends to the list, reply sends > to the original author). > > This should prevent the yahoo/gmail (or other dmarc) issues from > happening again. > > For others running mailings lists on CentOS with this issue, Red > Hat has back ported the 'dmarc_moderation_action' into the current > version of mailman that is used in RHEL and CentOS. You can follow > the instructions here for Mailman 2 (for version 2.1.18) even > though the version in CentOS is mailman-2.1.15-26.el7_4.1 > > we will be watching the list for the next few days to see if this > change is working as expected. If it id not working for other > email clients please let us know. > > Great job by Brian Stinson to figure all this out :) > > Thanks, > Johnny Hughes > Thank you - one less list I'll get kicked off of regularly. One note, I am seeing the author in the Reply-To: in the message headers, not in the visible Cc: as you indicate: From: Johnny Hughes via CentOS <centos at centos.org> Reply-To: Johnny Hughes <johnny at centos.org>, CentOS mailing list <centos at centos.org> so to see the address of the sender I have to either poke through the headers or initiate a reply. I don't think that this is email client specific.