[opendmarc-users] What causes Authentication Results to be Ignored?

[Bryan K. Walton]

Our opendmarc setup is working quite nicely, and has been.  However, for
about 1% (or even less) of our incoming emails, opendmarc logs something
like the following in our mail log:

Nov 14 03:25:24 shenandoah opendmarc[10263]: 6BE516C0787 ignoring
Authentication-Results at 5 from psa004.howardforums.com

In this particular example, this host (psa004.howardforums.com) is NOT
in our IgnoreHosts file.

Now, as you can see below, the DKIM check failed.  

DMARC-Filter: OpenDMARC Filter v1.3.2 shenandoah.leepfrog.com 6BE516C0787
Authentication-Results: shenandoah.leepfrog.com; dmarc=none (p=none dis=none)
header.from=howardforums.com
Authentication-Results: shenandoah.leepfrog.com; spf=pass
smtp.mailfrom=xxxxxx at howardforums.com
DKIM-Filter: OpenDKIM Filter v2.11.0 shenandoah.leepfrog.com 6BE516C0787
Authentication-Results: shenandoah.leepfrog.com;
    dkim=fail reason="key not found in DNS" (0-bit key; unprotected)
    header.d=howardforums.com header.i=@howardforums.com
    header.b="WRUCaQqp";
    dkim-atps=neutral

But this email domain, howardforums.com doesn't have any DMARC records
(p=none, above).

Is opendmarc reporting that it is ignoring the DKIM
Authentication-Results?  Why is that even getting logged? (MilterDebug
is set to the defaul "0")

I should also add that some of these "ignoring . . ." log messages
happen on emails where DKIM and SPF were successful:

Nov 13 10:00:10 shenandoah opendkim[6297]: C88065DBC9: DKIM verification
successful
Nov 13 10:00:10 shenandoah opendmarc[31699]: C88065DBC9 ignoring
Authentication-Results at 4 from mail1-1.macewan.ca
Nov 13 10:00:10 shenandoah opendmarc[31699]: C88065DBC9: SPF(mailfrom):
xxxxxx at macewan.ca pass
Nov 13 10:00:10 shenandoah opendmarc[31699]: C88065DBC9: macewan.ca none

Thanks!
Bryan