[Mimedefang] [MIMEDefang] Postfix add headers to outgoing mails

[M.Roessler at t-systems.com]

Hi folks, 

sorry for my very basic questions about this milter and the necessary configuration to bind to the MTA. 
I'm very new in this field, but i searched the whole week for a solution and look at so much howtos, threads and other stuff. Please help me with this.

My situation at the moment:

My main goal is to add two headers on outbound mails which are send over postfix.
First i try this with the postfix feature header_checks and the PREPEND action to add the 2 headers which we need.
It seems that fir this only one rule with PREPEND is allowed in the header_check file, cause of the mechanism postfix go through them.

Now my new approach is using a milter on postfix, who i've read should such a tool should be able to add more then one header in a mail.
I decided for MIMEDefang. I read some HowTo's to bind this extra linux service on my postfix server, hopefully done this correct.
After that i rewrote the whole /etc/mail/mimedefang-filter, but the headers will never be added.
I dont find a log file from mimedefang for debugging purposes and also dont see anything in the maillog when i append "-vvv" in postfix master.cf after this line:
"smtp      inet  n       -       n       -       -       smtpd"

(System is CentOS7)

Configuration files:

########
#main.cf#
################################
smtpd_milters = inet:127.0.0.1:10025
################################


########################
#/etc/mail/mimedefang-filter#
########################################################################

sub filter_end {
        if ( $Sender =~ /^<?noreply at domain-part.tld>?$/i ) {
                action_add_header("X-Auto-Response-Suppress", "DR,RN,NRN,OOF,AutoReply");
                action_add_header("Precedence", "list");
        }
}
1;
########################################################################


Kind regards,

Max Rößler

T-Systems Multimedia Solutions GmbH
Application Management & Cloud Services
Business Unit Application Management & Cloud Services
Max Rößler
System Engineer
Address: Riesaer Straße 7, 01129 Dresden, Germany
Postal address: Postfach 10 02 24, 01072 Dresden, Germany
+49 351 2820-7012 (Tel)
+49 160 7186124 (Mobil)
E-Mail:    Max.Roessler at t-systems.com
Internet:  http://www.t-systems-mms.com

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