Re: What I've been wondering about the DMARC problem

Theodore Ts'o <> Tue, 15 April 2014 03:23 UTC

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Date: Mon, 14 Apr 2014 23:23:13 -0400
From: Theodore Ts'o <>
To: Doug Barton <>
Subject: Re: What I've been wondering about the DMARC problem
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On Mon, Apr 14, 2014 at 08:04:15PM -0700, Doug Barton wrote:
> Simple ... from Yahoo!'s perspective the breakage is negligible, not
> serious. Traditional e-mail traffic to and from traditional e-mail lists
> (like this one) is simply not large enough to lose sleep over. Keep in mind,
> Yahoo! knew what breakage was going to occur before they threw the switch,
> and they threw the switch anyway.
> Again, I realize that it's hard for most IETF'ers to conceive of, but in
> this matter we are the ultimate anachronists.

The problem is that e-mail volume really is the wrong way to measure
"breakage".  After all, the vast majority of e-mail may be SPAM, but
that doesn't mean that those e-mail messages are the ones that any
users care about.

I've already had to send out message to my church's vestry (governing
board) explaining that people who are using Yahoo aren't going to be
able to send to the church mailing lists reliably, and that for now,
until I can get around to fixing the mailing list software (hint: not
during Holy Week), that their messages will be held for moderation
until someone can manually cut and paste it and send it on their

I've also explained that if they care, they should consider
complaining to Yahoo and/or switching e-mail providers.

If enough people do the same, maybe Yahoo will reconsider.  If not, so
long most of my e-mail community switches mail providers (i.e.,
treating as damage, and routing around it), I may not care
all that much.

In the maintime, if someone has had the time to hack together some
patches to mailman to write the from field of users to be  Please send them my way; I'll be most grateful.

		    	   	     	- Ted