Anyone on this list that knows the mail admins/contacts for
centurylink.net and embarqmail.com? This mail server has legit email
for centurylink.net and embarqmail.com plus a lot of other spam coming
out of it.
It's listed on a number of RBLs making this very hard to allow ham
through and block spam.
http://multirbl.valli.org/lookup/206.152.134.66.html
The PTR and A records for this IP are mail.onyx.syn-alias.com which is
also a bit odd since the SMTP HELO is smtp.centurylink.net. These don't
have to match but it's best if they did to help prove ownership and
trustworthiness.
https://pastebin.com/YidWCqp8
I have had a customer of ours request whitelisting of centurylink.net
and embarqmail.com email based on this problem and it's causing
problems. It can't be whitelisted due to a lot of junk coming from it
so I had to make some custom local rules to do this.
It would be best if the centurylink.net and embarqmail.com mail didn't
egress onto the Internet from an IP that was listed on so many RBLs.
SOLUTION: Setup a new mail relay with FCrDNS and the SMTP HELO matching
and get SPF and DKIM working properly for centurylink.net and
embarqmail.com so the rest of the Internet can properly filter/allow
this email.
--
David Jones
