[Rspamd-Users] Disable DKIM signature for mailing lists

[Arno Welzel]

Ihor Antonov:

> A lot of mailing lists forward emails and thus ruin my DKIM signature.
> My Inbox fills in with MAILER-DAEMON reports about DKIM signature 
> mismatch when, all of them from recipients who got my message through 
> some mailing list.

The problem: using DKIM on its own is not really useful without DMARC.
Usually you want to combine DKIM with DMARC, so a receiving mail server
will not accept mails from your domain without a valid DKIM signature,
or at least it will treat those mails as "spammy".

So if you omit DKIM signatures for certain mailing lists, you also
violate DMARC as spammers would do, when they fake your sender address
to get their spam delivered.

The real fix is not to avoid DKIM for specific recipients but to ask the
mailing list maintainers to set up their lists in a way to deal with it.

Also see here:
<https://begriffs.com/posts/2018-09-18-dmarc-mailing-list.html>