Keld Simonsen:
> What is happening is that the postfix server receives the message
> on port 25, via ESMTP, then delivers it via the the alias file to
> a list of recipients, recorded in the file /some/file/in/the/filesystem,
> which is included via a line in /etc/postfix/aliases :
For submission with SMTP, the VERP_README document has different
instructions (send "MAIL FROM:<senderaddress> XVERP=+="). If it is
not possible to configure the non-Postfix SMTP client this way,
then the options are:
1) Use a "simple" content filter that invokes the Postfix sendmail
command with the -XV option. This filter copies the message content
without modification. See also the FILTER_README file.
/etc/postfix/master.cf:
smtp inet n - n - - smtpd
-o content_filter=filter:
filter unix - n n - - pipe
user=nobody argv=/some/where/filter -f ${sender} ${recipient}
/some/where/filter:
#!/bin/sh
# Usage: /some/where/filter -f sender recipient..
/usr/sbin/sendmail -XV "$@"
Don't forget to "chmod a+rx /some/where/filter".
2) Use an SMTP-based content filter (per FILTER_README or
SMTPD_PROXY_README instructions) that modifies the MAIL FROM
command by appending the "VERP=+=" parameter. This filter copies
the message without content modification.
3) With Postfix 2.7 or later, use the smtpd_command_filter feature
to modify incoming "MAIL FROM" commands and append the "VERP=+="
parameter.
/etc/postfix/main.cf:
smtpd_authorized_verp_clients = 1.2.3.4
smtpd_command_filter = pcre:/etc/postfix/command_filter.pcre
/etc/postfix/command_filter.pcre
/^MAIL\s+FROM:(listsender.*)/ MAIL FROM:$1 VERP=+=
Wietse