[opendmarc-users] Setting up with multiple domains

[A. Schulze]

Mick:

> I have 4 domains that each receive email through the same postfix  
> MTA instance,

In the reporting model of DMARC the /destination domain/ isn't the  
information.
A receiving MTA report about /sender domains/.

So if you are an MX for numerous domains it does not matter if it's exact one
or 100k. Aggregate reports tell:

    "We received a message from host 2001:db8:: claim to be 'example.com'.
     That message was validated using SPF and DKIM.
     The result for each check was ...
     Our action was [pass|quarantine|reject]"

(Hope, I miss nothing ...)

-> Don't hesitate start sending aggregated reports!

Andreas