    BOUNCE(5)                                                            BOUNCE(5)

    NAME
           bounce - Postfix bounce message template format

    SYNOPSIS
           bounce_template_file = /etc/postfix/bounce.cf

           postconf -b [template_file]

    DESCRIPTION
           The  Postfix  bounce(8)  server  produces  delivery status notification
           (DSN) messages for undeliverable mail, delayed mail, successful  deliv-
           ery 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_tem-
           plate_file configuration parameter.

           This document describes the general procedure to create a  bounce  tem-
           plate  file,  followed  by the specific details of bounce template for-
           mats.

    GENERAL PROCEDURE
           To create a customized bounce template file, create a temporary copy of
           the file /etc/postfix/bounce.cf.default 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 con-
           figuration directory and specify in main.cf something like:

           /etc/postfix/main.cf:
               bounce_template_file = /etc/postfix/bounce.cf

    TEMPLATE FILE FORMAT
           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   ver-
           ify_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  (tem-
           plate_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
               EOF

           The  usage and specification of bounce templates is subject to the fol-
           lowing restrictions:

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

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

           o      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 bounce.cf.default in
           the Postfix configuration directory.

    TEMPLATE HEADER FORMAT
           The first portion of a bounce template consists  of  optional  template
           headers.   Some become message headers in the delivery status notifica-
           tion; 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:

           Charset:
                  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
                  notification.

           Subject:
                  The subject in the message header of the delivery status notifi-
                  cation that is returned to the sender.

           Postmaster-Subject:
                  The subject that will be used in Postmaster copies of undeliver-
                  able  or delayed mail notifications. These copies are sent under
                  control of the notify_classes configuration parameter.

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

           o      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:".

           o      Template message headers must not span multiple lines.

           o      Template message headers do not support $parameter expansions.

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

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

           delay_warning_time_suffix
                  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.

           maximal_queue_lifetime_suffix
                  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.

           mydomain
                  Expands into the value of the mydomain  parameter.   With  "smt-
                  putf8_enable  = yes", this replaces ACE labels (xn--mumble) with
                  their UTF-8 equivalent.

                  This feature is available in Postfix 3.0.

           myhostname
                  Expands into the value of the myhostname parameter.  With  "smt-
                  putf8_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:

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

           o      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 tem-
                  plate when it sends a delivery status notification.

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

    LICENSE
           The Secure Mailer license must be distributed with this software.

    HISTORY
           The Postfix bounce template format was originally developed by  Nicolas
           Riendeau.

    AUTHOR(S)
           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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