On 24 Nov 2015, at 13:47, David Jones wrote:
Could this be dependent on the MTA used? I am using Postfix
which puts in Received headers like this:
Received: from econnect.dmsgs.com (unknown [8.224.216.57])
That IP has a PTR record but it doesn't match the SMTP HELO of
econnect.dmsgs.com so Postfix is putting in the 'unknown' causing
the RDNS_NONE hit on more than just no rDNS.
Incorrect. The HELO name (econnect.dmsgs.com) is not involved at all in
why Postfix puts 'unknown' inside the parentheses.
Postfix puts "unknown" there because the PTR resolves to
smtp-55-unassigned.dmsgs.com but smtp-55-unassigned.dmsgs.com has no A
record resolving back to 8.224.216.57. It appears that the people
running DNS for 216.224.8.in-addr.arpa and dmsgs.com (apparently Digital
Messaging Solutions, Inc. of Tuscon AZ, USA) have screwed up. Many
nearby IPs also allocated to them have PTRs that resolve to names that
have As resolving back to the IP, so presumably they aren't entirely
incompetent...
