Re: MTA (DMARC)

[Reco <recoverym4n@enotuniq.net>]

	Hi.

On Sat, Jul 10, 2021 at 05:49:44AM -0400, Polyna-Maude Racicot-Summerside wrote:
> >> Here what I got from the Debian mailing list server
> >> Got some idea ?
> > 
> > Your MTA signs these headers:
> > 
> > Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:Cc:References:To:From:Subject:Sender:Reply-To:
> >         Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date:
> >         Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:
> >         List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive;
> > 
> > Of those at least these headers are modified by the list software:
> > 
> >         Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id:
> >         List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive;
> > 
> > Thus DKIM checks of your e-mails are bound to fail.
> > 
> I am currently using the email provided by my shared hosting.

That only means that the current setup of that MTA is unsuitable for the
list.
If you do not control it so you cannot change it - that can only mean
three things:

1) You'll continue to receive DMARC reports each time you send a e-mail
to the list, and they will show failed DKIM checks.

2) Your e-mails that are resent by bendel.d.o will fail DKIM checks, so
you have no guarantees that your e-mails will be received by all
subscribers of this list.

3) And last, but not least - it's up to the receiver MTA do decide what
to do with such broken e-mails - mark them as spam, deny receiving them,
or deliver to the intended addressee.


> For me it's somewhat complex to manage the setup of a email server,

These things require some learning indeed.


> even if I do also rent a bare metal server in a data center.

Whenever an MTA is running on a bare metal, some sort of virtualized
environment or even in a container is hardly relevant.

Reco