bounce - Postfix bounce message template format


   bounce_template_file = /etc/postfix/

   postconf -b [template_file]


   The  Postfix  bounce(8)  server  produces  delivery status notification
   (DSN)  messages  for  undeliverable  mail,  delayed  mail,   successful
   delivery or address verification requests.

   By  default,  these notifications are generated from built-in templates
   with message headers and message text. Sites can override the  built-in
   information   by   specifying   a   bounce   template   file  with  the
   bounce_template_file configuration parameter.

   This document describes  the  general  procedure  to  create  a  bounce
   template  file,  followed  by  the  specific details of bounce template


   To create a customized bounce template file, create a temporary copy of
   the file /etc/postfix/ and edit the temporary file.

   To  preview  the  results of $name expansions in the template text, use
   the command

       postconf -b temporary_file

   Errors in the template will be reported to the  standard  error  stream
   and to the syslog daemon.

   While  previewing  the text, be sure to pay particular attention to the
   expansion of time value parameters that  appear  in  the  delayed  mail
   notification text.

   Once  the  result  is  satisfactory,  copy  the template to the Postfix
   configuration directory and specify in something like:

       bounce_template_file = /etc/postfix/


   The template file can specify templates for failed mail, delayed  mail,
   successful  delivery  or for address verification.  These templates are
   named   failure_template,    delay_template,    success_template    and
   verify_template,  respectively.  You can but do not have to specify all
   four templates in a bounce template file.

   Each template starts with "template_name = <<EOF" and ends with a  line
   that contains the word "EOF" only. You can change the word EOF, but you
   can't  enclose  it  in  quotes  as  with  the  shell   or   with   Perl
   (template_name = <<'EOF'). Here is an example:

       # The failure template is used for undeliverable mail.

       failure_template = <<EOF
       Charset: us-ascii
       From: MAILER-DAEMON (Mail Delivery System)
       Subject: Undelivered Mail Returned to Sender
       Postmaster-Subject: Postmaster Copy: Undelivered Mail

       This is the mail system at host $myhostname.

       I'm sorry to have to inform you that your message could not
       be delivered to one or more recipients. It's attached below.

       For further assistance, please send mail to postmaster.

       If you do so, please include this problem report. You can
       delete your own text from the attached returned message.

                          The mail system

   The  usage  and  specification  of  bounce  templates is subject to the
   following restrictions:

   *      No special meaning is given to the  backslash  character  or  to
          leading whitespace; these are always taken literally.

   *      Inside  the << context, the "$" character is special. To produce
          a "$" character as output, specify "$$".

   *      Outside the << context, lines beginning with "#" are ignored, as
          are empty lines, and lines consisting of whitespace only.

   Examples of all templates can be found in the file in
   the Postfix configuration directory.


   The first portion of a bounce template consists  of  optional  template
   headers.    Some   become   message  headers  in  the  delivery  status
   notification; some control the formatting of that notification. Headers
   not specified in a template will be left at their default value.

   The following headers are supported:

          The  MIME  character  set of the template message text.  See the
          "TEMPLATE MESSAGE TEXT FORMAT" description below.

   From:  The sender address in the message header of the delivery  status

          The  subject  in  the  message  header  of  the  delivery status
          notification that is returned to the sender.

          The  subject  that  will  be  used  in  Postmaster   copies   of
          undeliverable  or  delayed  mail notifications. These copies are
          sent  under  control   of   the   notify_classes   configuration

   The  usage  and specification of template message headers is subject to
   the following restrictions:

   *      Template message header names can be specified  in  upper  case,
          lower case or mixed case. Postfix always produces bounce message
          header labels of the form "From:" and "Subject:".

   *      Template message headers must not span multiple lines.

   *      Template message headers do not support $parameter expansions.

   *      Template message headers must contain ASCII characters only, and
          must not contain ASCII null characters.


   The  second  portion  of a bounce template consists of message text. As
   the above example shows, template  message  text  may  contain
   $parameters.  Besides  the  parameters that are defined in, the
   following parameters are treated specially depending on the suffix that
   is appended to their name.

          Expands  into  the  value  of  the delay_warning_time parameter,
          expressed in the time unit specified by suffix, which is one  of
          seconds, minutes, hours, days, or weeks.

          Expands  into the value of the maximal_queue_lifetime parameter,
          expressed in the time unit specified by suffix.  See above under
          delay_warning_time for possible suffix values.

          Expands   into  the  value  of  the  mydomain  parameter.   With
          "smtputf8_enable = yes", this replaces ACE  labels  (xn--mumble)
          with their UTF-8 equivalent.

          This feature is available in Postfix 3.0.

          Expands  into  the  value  of  the  myhostname  parameter.  With
          "smtputf8_enable = yes", this replaces ACE  labels  (xn--mumble)
          with their UTF-8 equivalent.

          This feature is available in Postfix 3.0.

   The  usage and specification of template message text is subject to the
   following restrictions:

   *      The template message text is not sent in  Postmaster  copies  of
          delivery status notifications.

   *      If  the  template  message  text  contains non-ASCII characters,
          Postfix requires that the Charset: template header  is  updated.
          Specify  an  appropriate  superset  of  US-ASCII.  A superset is
          needed because Postfix appends  ASCII  text  after  the  message
          template when it sends a delivery status notification.


   bounce(8), Postfix delivery status notifications
   postconf(5), configuration parameters


   The Secure Mailer license must be distributed with this software.


   The  Postfix bounce template format was originally developed by Nicolas


   Wietse Venema
   IBM T.J. Watson Research
   P.O. Box 704
   Yorktown Heights, NY 10598, USA

   Wietse Venema
   Google, Inc.
   111 8th Avenue
   New York, NY 10011, USA



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