Incoming SMTP in the year 2017 and absence of DKIM

Grant Taylor gtaylor at
Wed Nov 29 21:35:43 UTC 2017

On 11/29/2017 02:13 PM, John Levine wrote:
> A mailing list sending with bad rDNS or bad SPF is a pretty cruddy 
> mailing list.

s/mailing list sending/sending server/


> Normal lists put their own bounce address in the 
> envelope so they can handle the bounces, so their own SPF applies.

Yep.  V.E.R.P. is a very powerful thing.  (B.A.T.V. is an interesting 
alternative, but I never messed with it.)

> No idea why you think rDNS for a list's MTA is any harder than anyone 
> else's MTA.

I don't.

I'm saying that I've heard arguments over the last 15 years from people 
that (FC)rDNS and SPF (independently) are things that will break some 
portion of email.  -  I believe that these are simply technologies that 
the email industry has adopted and now considers to be Best Practice, if 
not actual requirements that MUST be done.

IMHO, Mailing List Managers are simply a different form of MUA that 
utilizes the same email infrastructure (MTAs.)  Thus, MLMs are subject 
tot he same requirements as "individual email" (as referred to earlier.)

Grant. . . .
unix || die

P.S.  I'm strongly of the opinion that if a MLM alters the message in 
ANY capacity, that it is actually generating a new message.  Thus the 
MLM is the new author.  It's just using content strongly based on emails 
that came into it.  -  But that's a different discussion that lasted 
days on the mailman mailing list.

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