That would be a reasonable supposition --srs
> On 28-Feb-2016, at 8:53 AM, Mark Jeftovic <[email protected]> wrote: > > >> On 2016-02-27 9:59 PM, Suresh Ramasubramanian wrote: >> A domain with a null mx may well originate email but will absolutely not >> receive email - so mail gets trashed at your end as well without staying >> endlessly on your mall queues >> >> You can possibly correlate that mx with the behavior of domains that are >> sending you mail.. Though a domain rather than IP bl may make sense. > > Sorry, I realized after I sent that I needed to clarify that what I'm > observing are MTAs attempting to deliver email to addresses at IP of the > A record for the domain, ignoring the presence of its NULL MX. > > So the originating MTAs are ignoring the NULL MX and attempting to > deliver to the A hostname, leading me to surmise they are spambots or > zombies. > > - mark > >> --srs >> >>> On 28-Feb-2016, at 8:07 AM, Mark Jeftovic <[email protected]> wrote: >>> >>> >>> What is an MTA supposed to do with a message addressed to a domain with >>> a NULL MX? >>> >>> RFC 7505 talks about domains with a NULL MX should not originate email >>> (in their sender envelopes, etc) but what about the converse? >>> >>> I'm looking at some logs and seeing attempts to deliver email to lots of >>> domains with NULL MX enabled (that have been so for years) and wondering >>> if I can safely mine these logs and add all the originating MTA IPs to >>> an internal RBL. >>> >>> I think I can. I think I will. >>> >>> - mark >>> >>> -- >>> Mark Jeftovic, Founder & CEO, easyDNS Technologies Inc. >>> Company Website: http://easydns.com >>> Read my blog: http://markable.com >>> +1-416-535-8672 ext 225 >>> >>> _______________________________________________ >>> mailop mailing list >>> [email protected] >>> https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop > > -- > Mark Jeftovic, Founder & CEO, easyDNS Technologies Inc. > Company Website: http://easydns.com > Read my blog: http://markable.com > +1-416-535-8672 ext 225 _______________________________________________ mailop mailing list [email protected] https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop
