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 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 config-
uration 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 tem-
porary 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 verifica-
tion. 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 $myhostname.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to postmaster.
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
The mail system
EOF
The usage and specification of bounce templates is subject
to the following restrictions:
o No special meaning is given to the backslash char-
acter or to leading whitespace; these are always
taken literally.
o Inside the << context, the "$" character is spe-
cial. To produce a "$" character as output, specify
"$$".
o Outside the << context, lines beginning with "#"
are ignored, as are empty lines, and lines consist-
ing 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 format-
ting of that notification. Headers not specified in a tem-
plate 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:
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 charac-
ters only, and must not contain ASCII null charac-
ters.
TEMPLATE MESSAGE TEXT FORMAT
The second portion of a bounce template consists of mes-
sage text. As the above example shows, template message
text may contain main.cf $parameters. Besides the parame-
ters 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_life-
time parameter, expressed in the time unit speci-
fied by suffix. See above under delay_warning_time
for possible suffix values.
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: tem-
plate 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 devel-
oped by Nicolas Riendeau.
AUTHOR(S)
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA
BOUNCE(5)