[Rhodes22-list] Rhodes22 Mailman list and DMARC issues

[Michael Weisner]

This posting is not about sailing.  If you are interested in the mechanics of the mail delivery via “da list” you may find this posting worth the time to read.  If not, just hit DELETE and wait for mail about sailing.

 

The lack of a sender’s name in the From line of the Rhodes22-list is not a bug.  It is the direct result of trying to comply with the DMARC email rules.

 

In an attempt to reduce the quantity of spam, ISPs have created hurdles for mailing lists using DMARC (Domain-based Message Authentication, Reporting & Conformance) standards.  It adds a reporting function that allows senders and receivers to improve and monitor protection of the domain from fraudulent email.

 

To prevent issues with DMARC which caused automated member unsubscribing from “da list” due to ISP rejected emails in the past, John removed the sender information, making “da list” anonymous.  This worked and we were able to continue to send and receive emails as a list.

 

The current list server was built with a new and improved version of the mailman list manager (2.1.18) which attempts to fix the DMARC issue.  The developers of the mailman software have published the following:

 

DMARC is a standard developed as a technique to reduce email spam and phishing.  Unfortunately, it has negative consequences for mailing lists, essentially breaking long established mailing list norms, standards, and behaviors.   Yahoo! recently began publishing a DMARC policy for rejecting all messages that fail the signature tests, and every mailing list with Yahoo! members started seeing bounces from these members.  This has caused the Mailman community of members, list administrators, and developers enormous pain.

 

Mitigating the effects of the DMARC reject policy are difficult.  All known mitigation techniques break some user expectations and/or degrade the user experience.  Still, it's incumbent on the Mailman developers to try to reduce the pain our users feel, and to provide some options for site and list administrators who find themselves caught in the middle.   This page attempts to capture the Mailman developers' current thinking about the problem.

 

Solutions are difficult and complicated.  The DMARC authors essentially acknowledge that adopting DMARC requires changing mailing list habits.  You cannot continue to run your mailing list the way you always have, in DMARC compatible way.  Mailman 2.1.16 was the first version that added some workarounds for DMARC rejections, with refinements ongoing in subsequent releases.

 

As a result, I have changed the list configuration from “anonymous”  to “Rewrite the From: header with the posters name 'via the list' and the list's address and merge the poster's address into Reply-To:” in an effort to restore some of the sender’s information.  If it works, great!  if I start getting a lot of rejected emails due to DMARC, I will set us to anonymous again.  This is a test.

 

Mike

s/v Windlass ('91)

Nissequogue River, NY

 

-----Original Message----- Sent: Wednesday, April 13, 2016 9:54 PM
Robert,

 

The lack of transparent names is kind of unique to this list.  It’s not a feature, it’s a bug.

 

{clip}

 

Peter Nyberg

Coventry, CT

No Boat Yet (but next week, according to the current plan)

 

 

> On Apr 13, 2016, at 8:55 PM, The Rhodes 22 Email List < <mailto:rhodes22-list at rhodes22.org> rhodes22-list at rhodes22.org> wrote:

> 

> Thanks for the info and encouragement.  I an new to the list and did 

> not realize that names or user names did not appear.

> 

> Robert