Outgoing through


I have my postfix configured to send outgoing mail through port 587 (submission) but in the log I only get[12341]: DKIM verify - none; message-id=<3b0f402c738b18a8a222fb3cf…
when I send a message.
And I think that’s why my mails aren’t being signed.

Is this normal? When sending mails shouldn’t I see in log dkimproxy.**out **message instead of

I realised that if I put outgoing mails through port 25 it appears dkimproxy.out line in the log with the message signed. But when I test DKIM it says that I’m not signing the mail.

Any clue?


Your terminology is slightly wrong here. Postfix does not send outgoing mail on port 587 - it accepts mail on 587. This mail is then relayed to an MTA on port 25.

Anyway, that aside, I believe the answer to your problem is a slight over-sight. Please make sure you have this line in $postfix/

587 inet n - - - - smtpd
-o content_filter=dksign:[]:10027

postfix reload

That should do the trick.

Christopher J. Buckley