DNS settings for DMARC

Hi there,

first of all: Thanks a lot for creating this awesome service! I’ve been running my box for a while now and so far it works like a charm.

Currently I am not using the box as a name server for my domain, mostly because of restrictions set by my provider. I have however taken a quick look at the DNS settings, as displayed on the Custom DNS page in the admin panel, especially the DMARC settings.

It looks to me like those are set to “quarantine” for both the domain and the MX, and to “reject” for the name servers.

As a regular user of various mailing lists (and a contributer to GNU Mailman), I am worried that these defaults might make it impossible for Mail-in-a-box users to post to any mailing lists (or at least those MLs which re-use the From:-Header of the original sender, which is probably a good part of all open source mailing lists).

So my questions are these:

  1. If I decide to use my box as a name server, is there an easy way to set the dmarc record to ‘none’, at least for the domain and the MX?

  2. Isn’t this something that should be selectable or at least mentioned during setup, so people are aware of the ramifications for their use of mailing lists?

Again, thanks for this incredible tool!

Florian Fuchs

1 Like


  1. No there’s no way to override it now.

  2. There are basically no installation options at all now. It’s the only way that I won’t go insane trying to support all sorts of different configurations.

Mail lists that cause trouble are not compliant with modern mail standards, so I don’t intend to work around them. Note that this isn’t about preserving From:, but preserving From: and altering the message — that’s what’s not permissible under DMARC.

There’s a related note that shows in the Mail Instructions page of the admin, and we could add something about mail lists there.

I have had issues with DMARC over the last week (first week of usage of Mail-in-a-box) gmail have put my emails in spam folder due to failing DMARC. The linux vger mailing lists alter the footer and add “X-Mailing-List:” header among others.

I was able to update custom dmarc record (_dmarc.domain.tld) from the admin panel now to the following:

v=DMARC1; p=none; rua=mailto:mailauth-reports@domain.tld

Remember to alter the email address or add an alias for the mailauth reports.

Thanks for this. An old post but helpful!