I have a question which is not about the configuration but about the question what is right and what not.
Organisation A (OrgA) has a Mailserver which is responsible for
example.org. The Head of OrgA is also Head of Company B (CompB,
example.com). Now the it guys from OrgA used their Postfix aliases file to forward all mails for
Should look like this:
cat /etc/postfix/aliases Head.Boss:Head.Boss@example.com
Now a worker of CompanyC writes an email to
Head.Boss@example.org which gets "redirected" to
Head.Boss@example.com. In that case the Mailserver of OrgA acts as simple mail relay, right? If CompanyC provides a SPF record and CompanyB checks this one there should be a failure because the mailserver of OrgA does not match with the SPF of the sender CompanyC.
Is it a good manner to redirect mails to external addresses like that? Or shouldn't that matter because there is no DMARC Record which tells to drop messages not matching the SPF?