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BOUNCE(5)                     File Formats Manual                    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
       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
       formats.

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
       configuration 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
       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
           EOF

       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 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
       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:

       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
              notification that is returned to the sender.

       Postmaster-Subject:
              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
              parameter.

       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.

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
              "smtputf8_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
              "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.

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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