I saw some people using email addresses like yahoo, AOL, mail.ru to
post messages to the lists (such as debian-user, postfix-user etc).
I am thinking those addresses which have the strictest DKIM setup are
not suitable to send a list mail, they will be blocked by many
recipients (list members).
For example, yahoo has this DMARC setting:
v=DMARC1; p=reject; pct=100; rua=mailto:d@rua.agari.com;
ruf=mailto:d@ruf.agari.com;
And Mail.ru:
v=DMARC1;p=reject;rua=mailto:dmarc_rua@corp.mail.ru
And zoho.com:
v=DMARC1; p=reject; sp=reject; fo=0;
rua=mailto:dmarcaggregation@zoho.com;
ruf=mailto:dmarcaggregation@zoho.com
The all have "p=reject" rules which mean when DKIM (most modern email
providers have this enabled) break at the recipient end, this mail
will be rejected by the recipient MTA.
As we know DKIM will fail due to:
1. SPF fail (for the From: address in header) - this will 100% happen
regardless list server implements SRS or not.
2. DKIM fail (for header address as well) - this will most probably
happen since some list servers change the message content by adding a
signature etc.
So we should choose a email address which at least has no "p=reject"
in their DKIM policy.