We have two separate RTs (request trackers) configured on one server. They both are configured to send the emails through sendmail. We are trying to configure now SPF and DMARC records for these DNS names. What we achieved for now is that SPF passes but DMARC fails. If I understood correctly the reason for DMARC fail is that From header of the email is set to [email protected] while Envelope From header is set to [email protected]. server.dns.name is added in the SPF record as the trusted one, so SPF passes.

Is there an option in sendmail to set Envelope From header the same as From? In other words we need it to be set dynamically to [email protected] or [email protected].

What I have currently found is using masquerade feature, but if I understood correctly only one DNS can be used there.

Or is there an option for DMARC to pass with the current difference in the domains in From headers?

1 Answer 1


You probably don't want to make your DMARC fit around bad data.

Sounds like you are using SMTP from RT. IIRC RT recommend a CLI invocation for outgoing mail - then you can easily set up a pipeline with (say) awk or Perl to rewrite the header FROM address, and then pass this on to sendmail -t -i (IIRC sendmail -f only forces the envelope from address).

  • RT is from Best Practical. I have found an option in the config file: # Set($SendmailBounceArguments , '-f "<>"');. Haven't tried it yet, but I guess this is what's needed. However, I was told one more surprise one of the RTs has queus with two different domains: so from one request tracker the emails are sent from support@domain1 and from support@domain2. And I've got no ideas how to rule this case....
    – Julia Mala
    Commented Aug 3, 2023 at 17:54
  • Isn't that what I just explicitly said won't solve the problem?
    – symcbean
    Commented Aug 3, 2023 at 20:59
  • my bad, sorry. you're right. gonna try your idea
    – Julia Mala
    Commented Aug 4, 2023 at 7:52

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .