Lots of people have wildcard TXT records which mean that if you look up a DMARC record you get an SPF record. They get the delivery they’d get with no DMARC record on the systems I know about and it doesn’t seem to annoy them enough to make them stop, which is reasonable evidence it doesn’t make a difference they can perceive elsewhere.
Elizabeth > On Apr 24, 2022, at 11:38 AM, John R Levine <[email protected]> wrote: > > Someone I know asked me what sort of bad things could happen if one > published a broken DMARC record. Obviously, if your record is bad people > won't follow your policies and you won't get your reports, but anything else? > Have you ever heard of MTAs burping on a bad DMARC record? > > I've looked at the C OpenDMARC and perl Mail::DMARC libraries and they both > seem pretty sturdy: fetch a TXT record and if they find one, look for the > tags they want and ignore everything else. > > As an experiment, I added 32K of junk to the _dmarc.johnlevine.com TXT record > and as far as I can tell, it's made no difference. I still get the same > reports saying the same things. DNS libraries need to use TCP to fetch it > but they all seem able to do that. > > Regards, > John Levine, [email protected], Taughannock Networks, Trumansburg NY > Please consider the environment before reading this e-mail. https://jl.ly > > _______________________________________________ > dmarc mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/dmarc _______________________________________________ dmarc mailing list [email protected] https://www.ietf.org/mailman/listinfo/dmarc
