[Toybox] Emails go nowhere

[Denys Nykula]

4 March 2020, 02:50:05 "Rob Landley" <rob at landley.net>:
> You're getting landley.net emails from_me_, but not dreamhost's own servers

No, according to the log, mailing list letters come from 64.90.62.195, which
is dreamhost. With a header, it asks recipient's server to display the letter as
though it comes from your domain. Following RFC 7208, recipient looks up your
domain records and checks if you allow the server from that network prefix to
send letters as you.

Your domain has no matching record, so a recipient's host complying to the
standard "SHOULD use an SMTP reply code of 550" to reject it as "not authorized
to use the domain in the given identity". The RFC about SPF was released 6 years
ago, mail providers allowed a grace term waiting for people to add the records,
which seems over.

Comparing at dnschecker.org/all-dns-records-of-domain.php the lists.landley.net
to musl's lists.openwall.com, I guess something like this is enough:

TXT	lists.landley.net	v=spf1 ip4:64.90.62.0/19 ?all	3599

But please ask dreamhost support for which precise records you should add. I
can't blindly suggest correct records without access to your account, and I
think an MX record is also needed (lists.landley.net isn't the same as
landley.net).