I noticed today that gmail has been putting almost all email from phabricator.wikimedia.org into the spam folder. When looking at such mails, I notice the following header:
Received-SPF: fail (google.com: domain of email@example.com does not designate 2620:0:861:102:10:64:16:8 as permitted sender) client-ip=2620:0:861:102:10:64:16:8;
This would indicate phabricator.wikimedia.org needs a DNS entry specifying an SPF policy that allows mx1001.wikimedia.org to send emails on behalf of it. If I'm understanding correctly, which I might not be.
(Not sure what tags or subsribers are best, so guessing. My apologies for guessing wrong.)
2620:0:861:102:10:64:16:8 has a PTR set to phab1001.eqiad.wmnet.