Re: DMARC methods in mailman

Philip Homburg <> Wed, 21 December 2016 16:09 UTC

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Subject: Re: DMARC methods in mailman
From: Philip Homburg <>
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In-reply-to: Your message of "Wed, 21 Dec 2016 07:22:13 -0800 ." <>
Date: Wed, 21 Dec 2016 17:09:32 +0100
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Cc: S Moonesamy <>
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>At 04:10 21-12-2016, Philip Homburg wrote:
>>Just to be clear, is this an option that individual subscribers of the mailin
>>list can set?
>No.  You can view the options available to individual subscribers at 

The point of my proposal was to make an option per subscriber.

The most sane way to deal with systems that reject or otherwise discard mail
that fails DMARC checks is to rewrite the From.

However, for other people, is a regression for various reasons.

So the only sensible way forward is to have a per subscriber option. 

>>Or are you saying that at the moment 40% of the subscribers of IETF 
>>lists reject
>>or otherwise not receive mail from DMARC protected senders?
>The 40% was statistics about one IETF mailing list only.  Messages 
>from the mailing list to those (40%) subscribers would not be 
>rejected as some of the mail providers are not advertising a 
>"p=reject".  A number of the mail providers in that 40% will not 
>deliver messages from the mailing list to the subscribers as they are 
>advertising a "p=quarantine".

So is that one mailing list typical, or just a bunch of people who like to 
reject mail?

But apart from that, you are saying that for at least that one list, if
you send a mail to the list with a 'p=reject' then 40% of the subscribers are
not going to see that message.