POSTCONF(1) General Commands Manual POSTCONF(1)
NAME
postconf - Postfix configuration utility
SYNOPSIS
Managing main.cf:
postconf [-dfhHnopqvx] [-c config_dir] [-C class,...] [parameter ...]
postconf [-epv] [-c config_dir] parameter=value ...
postconf -# [-pv] [-c config_dir] parameter ...
postconf -X [-pv] [-c config_dir] parameter ...
Managing master.cf service entries:
postconf -M [-foqvx] [-c config_dir] [service[/type] ...]
postconf -M [-ev] [-c config_dir] service/type=value ...
postconf -M# [-v] [-c config_dir] service/type ...
postconf -MX [-v] [-c config_dir] service/type ...
Managing master.cf service fields:
postconf -F [-fhHoqvx] [-c config_dir] [service[/type[/field]] ...]
postconf -F [-ev] [-c config_dir] service/type/field=value ...
Managing master.cf service parameters:
postconf -P [-fhHoqvx] [-c config_dir] [service[/type[/parameter]] ...]
postconf -P [-ev] [-c config_dir] service/type/parameter=value ...
postconf -PX [-v] [-c config_dir] service/type/parameter ...
Managing bounce message templates:
postconf -b [-v] [-c config_dir] [template_file]
postconf -t [-v] [-c config_dir] [template_file]
Managing TLS features:
postconf -T mode [-v] [-c config_dir]
Managing other configuration:
postconf -a|-A|-l|-m [-v] [-c config_dir]
DESCRIPTION
By default, the postconf(1) command displays the values of main.cf con-
figuration parameters, and warns about possible mis-typed parameter
names (Postfix 2.9 and later). The command can also change main.cf con-
figuration parameter values, or display other configuration information
about the Postfix mail system.
Options:
-a List the available SASL plug-in types for the Postfix SMTP
server. The plug-in type is selected with the smtpd_sasl_type
configuration parameter by specifying one of the names listed be-
low.
cyrus This server plug-in is available when Postfix is built
with Cyrus SASL support.
dovecot
This server plug-in uses the Dovecot authentication
server, and is available when Postfix is built with any
form of SASL support.
This feature is available with Postfix 2.3 and later.
-A List the available SASL plug-in types for the Postfix SMTP
client. The plug-in type is selected with the smtp_sasl_type or
lmtp_sasl_type configuration parameters by specifying one of the
names listed below.
cyrus This client plug-in is available when Postfix is built
with Cyrus SASL support.
This feature is available with Postfix 2.3 and later.
-b [template_file]
Display the message text that appears at the beginning of deliv-
ery status notification (DSN) messages, expanding $name expres-
sions with actual values as described in bounce(5).
To override the bounce_template_file parameter setting, specify a
template file name at the end of the "postconf -b" command line.
Specify an empty file name to display built-in templates (in
shell language: "").
This feature is available with Postfix 2.3 and later.
-c config_dir
The main.cf configuration file is in the named directory instead
of the default configuration directory.
-C class,...
When displaying main.cf parameters, select only parameters from
the specified class(es):
builtin
Parameters with built-in names.
service
Parameters with service-defined names (the first field of
a master.cf entry plus a Postfix-defined suffix).
user Parameters with user-defined names.
all All the above classes.
The default is as if "-C all" is specified.
This feature is available with Postfix 2.9 and later.
-d Print main.cf default parameter settings instead of actual set-
tings. Specify -df to fold long lines for human readability
(Postfix 2.9 and later).
-e Edit the main.cf configuration file, and update parameter set-
tings with the "name=value" pairs on the postconf(1) command
line.
With -M, edit the master.cf configuration file, and replace one
or more service entries with new values as specified with "ser-
vice/type=value" on the postconf(1) command line.
With -F, edit the master.cf configuration file, and replace one
or more service fields with new values as specified with "ser-
vice/type/field=value" on the postconf(1) command line. Cur-
rently, the "command" field contains the command name and command
arguments. This may change in the near future, so that the "com-
mand" field contains only the command name, and a new "arguments"
pseudofield contains the command arguments.
With -P, edit the master.cf configuration file, and add or update
one or more service parameter settings (-o parameter=value set-
tings) with new values as specified with "service/type/parame-
ter=value" on the postconf(1) command line.
In all cases the file is copied to a temporary file then renamed
into place. Specify quotes to protect special characters and
whitespace on the postconf(1) command line.
The -e option is no longer needed with Postfix version 2.8 and
later, as it is assumed whenever a value is specified (empty or
non-empty).
-f Fold long lines when printing main.cf or master.cf configuration
file entries, for human readability.
This feature is available with Postfix 2.9 and later.
-F Show master.cf per-entry field settings (by default all services
and all fields), formatted as "service/type/field=value", one per
line. Specify -Ff to fold long lines.
Specify one or more "service/type/field" instances on the post-
conf(1) command line to limit the output to fields of interest.
Trailing parameter name or service type fields that are omitted
will be handled as "*" wildcard fields.
This feature is available with Postfix 2.11 and later.
-h Show parameter or attribute values without the "name = " label
that normally precedes the value.
-H Show parameter or attribute names without the " = value" that
normally follows the name.
This feature is available with Postfix 3.1 and later.
-l List the names of all supported mailbox locking methods. Postfix
supports the following methods:
flock A kernel-based advisory locking method for local files
only. This locking method is available on systems with a
BSD compatible library.
fcntl A kernel-based advisory locking method for local and re-
mote files.
dotlock
An application-level locking method. An application locks
a file named filename by creating a file named file-
name.lock. The application is expected to remove its own
lock file, as well as stale lock files that were left be-
hind after abnormal program termination.
-m List the names of all supported lookup table types. In Postfix
configuration files, lookup tables are specified as type:name,
where type is one of the types listed below. The table name syn-
tax depends on the lookup table type as described in the DATA-
BASE_README document.
btree A sorted, balanced tree structure. Available on systems
with support for Berkeley DB databases.
cdb A read-optimized structure with no support for incremental
updates. Available on systems with support for CDB data-
bases.
This feature is available with Postfix 2.2 and later.
cidr A table that associates values with Classless Inter-Domain
Routing (CIDR) patterns. This is described in cidr_ta-
ble(5).
This feature is available with Postfix 2.2 and later.
dbm An indexed file type based on hashing. Available on sys-
tems with support for DBM databases.
environ
The UNIX process environment array. The lookup key is the
environment variable name; the table name is ignored.
Originally implemented for testing, someone may find this
useful someday.
fail A table that reliably fails all requests. The lookup table
name is used for logging. This table exists to simplify
Postfix error tests.
This feature is available with Postfix 2.9 and later.
hash An indexed file type based on hashing. Available on sys-
tems with support for Berkeley DB databases.
inline (read-only)
A non-shared, in-memory lookup table. Example: "inline:{
key=value, { key = text with whitespace or comma }}".
Key-value pairs are separated by whitespace or comma; with
a key-value pair inside "{}", whitespace is ignored after
the opening "{", around the "=" between key and value, and
before the closing "}". Inline tables eliminate the need
to create a database file for just a few fixed elements.
See also the static: map type.
This feature is available with Postfix 3.0 and later.
internal
A non-shared, in-memory hash table. Its content are lost
when a process terminates.
lmdb OpenLDAP LMDB database (a memory-mapped, persistent file).
Available on systems with support for LMDB databases.
This is described in lmdb_table(5).
This feature is available with Postfix 2.11 and later.
ldap (read-only)
LDAP database client. This is described in ldap_table(5).
memcache
Memcache database client. This is described in mem-
cache_table(5).
This feature is available with Postfix 2.9 and later.
mongodb
MongoDB database client. This is described in mongodb_ta-
ble(5).
This feature is available with Postfix 3.9 and later.
mysql (read-only)
MySQL database client. Available on systems with support
for MySQL databases. This is described in mysql_table(5).
pcre (read-only)
A lookup table based on Perl Compatible Regular Expres-
sions. The file format is described in pcre_table(5).
pgsql (read-only)
PostgreSQL database client. This is described in pgsql_ta-
ble(5).
This feature is available with Postfix 2.1 and later.
pipemap (read-only)
A lookup table that constructs a pipeline of tables. Ex-
ample: "pipemap:{type_1:name_1, ..., type_n:name_n}".
Each "pipemap:" query is given to the first table. Each
lookup result becomes the query for the next table in the
pipeline, and the last table produces the final result.
When any table lookup produces no result, the pipeline
produces no result. The first and last characters of the
"pipemap:" table name must be "{" and "}". Within these,
individual maps are separated with comma or whitespace.
This feature is available with Postfix 3.0 and later.
proxy Postfix proxymap(8) client for shared access to Postfix
databases. The table name syntax is type:name.
This feature is available with Postfix 2.0 and later.
randmap (read-only)
An in-memory table that performs random selection. Exam-
ple: "randmap:{result_1, ..., result_n}". Each table query
returns a random choice from the specified results. The
first and last characters of the "randmap:" table name
must be "{" and "}". Within these, individual results are
separated with comma or whitespace. To give a specific re-
sult more weight, specify it multiple times.
This feature is available with Postfix 3.0 and later.
regexp (read-only)
A lookup table based on regular expressions. The file for-
mat is described in regexp_table(5).
sdbm An indexed file type based on hashing. Available on sys-
tems with support for SDBM databases.
This feature is available with Postfix 2.2 and later.
socketmap (read-only)
Sendmail-style socketmap client. The table name is
inet:host:port:name for a TCP/IP server, or unix:path-
name:name for a UNIX-domain server. This is described in
socketmap_table(5).
This feature is available with Postfix 2.10 and later.
sqlite (read-only)
SQLite database. This is described in sqlite_table(5).
This feature is available with Postfix 2.8 and later.
static (read-only)
A table that always returns its name as lookup result. For
example, static:foobar always returns the string foobar as
lookup result. Specify "static:{ text with whitespace }"
when the result contains whitespace; this form ignores
whitespace after the opening "{" and before the closing
"}". See also the inline: map.
The form "static:{text} is available with Postfix 3.0 and
later.
tcp (read-only)
TCP/IP client. The protocol is described in tcp_table(5).
texthash (read-only)
Produces similar results as hash: files, except that you
don't need to run the postmap(1) command before you can
use the file, and that it does not detect changes after
the file is read.
This feature is available with Postfix 2.8 and later.
unionmap (read-only)
A table that sends each query to multiple lookup tables
and that concatenates all found results, separated by
comma. The table name syntax is the same as for pipemap.
This feature is available with Postfix 3.0 and later.
unix (read-only)
A limited view of the UNIX authentication database. The
following tables are implemented:
unix:passwd.byname
The table is the UNIX password database. The key is
a login name. The result is a password file entry
in passwd(5) format.
unix:group.byname
The table is the UNIX group database. The key is a
group name. The result is a group file entry in
group(5) format.
Other table types may exist depending on how Postfix was built.
-M Show master.cf file contents instead of main.cf file contents.
Specify -Mf to fold long lines for human readability.
Specify zero or more arguments, each with a service-name or ser-
vice-name/service-type pair, where service-name is the first
field of a master.cf entry and service-type is one of (inet,
unix, fifo, or pass).
If service-name or service-name/service-type is specified, only
the matching master.cf entries will be output. For example,
"postconf -Mf smtp" will output all services named "smtp", and
"postconf -Mf smtp/inet" will output only the smtp service that
listens on the network. Trailing service type fields that are
omitted will be handled as "*" wildcard fields.
This feature is available with Postfix 2.9 and later. The syntax
was changed from "name.type" to "name/type", and "*" wildcard
support was added with Postfix 2.11.
-n Show only configuration parameters that have explicit name=value
settings in main.cf. Specify -nf to fold long lines for human
readability (Postfix 2.9 and later). To show settings that differ
from built-in defaults only, use the following bash syntax:
LANG=C comm -23 <(postconf -n) <(postconf -d)
Replace "-23" with "-12" to show settings that duplicate built-in
defaults.
-o name=value
Override main.cf parameter settings. This lets you see the ef-
fect changing a parameter would have when it is used in other
configuration parameters, e.g.:
postconf -x -o stress=yes
This feature is available with Postfix 2.10 and later.
-p Show main.cf parameter settings. This is the default.
This feature is available with Postfix 2.11 and later.
-P Show master.cf service parameter settings (by default all ser-
vices and all parameters), formatted as "service/type/parame-
ter=value", one per line. Specify -Pf to fold long lines.
Specify one or more "service/type/parameter" instances on the
postconf(1) command line to limit the output to parameters of in-
terest. Trailing parameter name or service type fields that are
omitted will be handled as "*" wildcard fields.
This feature is available with Postfix 2.11 and later.
-q Do not log warnings for deprecated or unused parameters.
This feature is available with Postfix 3.9 and later.
-t [template_file]
Display the templates for text that appears at the beginning of
delivery status notification (DSN) messages, without expanding
$name expressions.
To override the bounce_template_file parameter setting, specify a
template file name at the end of the "postconf -t" command line.
Specify an empty file name to display built-in templates (in
shell language: "").
This feature is available with Postfix 2.3 and later.
-T mode
If Postfix is compiled without TLS support, the -T option pro-
duces no output. Otherwise, if an invalid mode is specified, the
-T option reports an error and exits with a non-zero status code.
The valid modes are:
compile-version
Output the OpenSSL version that Postfix was compiled with
(i.e. the OpenSSL version in a header file). The output
format is the same as with the command "openssl version".
run-version
Output the OpenSSL version that Postfix is linked with at
runtime (i.e. the OpenSSL version in a shared library).
public-key-algorithms
Output the lower-case names of the supported public-key
algorithms, one per-line.
This feature is available with Postfix 3.1 and later.
-v Enable verbose logging for debugging purposes. Multiple -v op-
tions make the software increasingly verbose.
-x Expand $name in main.cf or master.cf parameter values. The expan-
sion is recursive.
This feature is available with Postfix 2.10 and later.
-X Edit the main.cf configuration file, and remove the parameters
named on the postconf(1) command line. Specify a list of parame-
ter names, not "name=value" pairs.
With -M, edit the master.cf configuration file, and remove one or
more service entries as specified with "service/type" on the
postconf(1) command line.
With -P, edit the master.cf configuration file, and remove one or
more service parameter settings (-o parameter=value settings) as
specified with "service/type/parameter" on the postconf(1) com-
mand line.
In all cases the file is copied to a temporary file then renamed
into place. Specify quotes to protect special characters on the
postconf(1) command line.
There is no postconf(1) command to perform the reverse operation.
This feature is available with Postfix 2.10 and later. Support
for -M and -P was added with Postfix 2.11.
-# Edit the main.cf configuration file, and comment out the parame-
ters named on the postconf(1) command line, so that those parame-
ters revert to their default values. Specify a list of parameter
names, not "name=value" pairs.
With -M, edit the master.cf configuration file, and comment out
one or more service entries as specified with "service/type" on
the postconf(1) command line.
In all cases the file is copied to a temporary file then renamed
into place. Specify quotes to protect special characters on the
postconf(1) command line.
There is no postconf(1) command to perform the reverse operation.
This feature is available with Postfix 2.6 and later. Support for
-M was added with Postfix 2.11.
DIAGNOSTICS
Problems are reported to the standard error stream.
ENVIRONMENT
MAIL_CONFIG
Directory with Postfix configuration files.
CONFIGURATION PARAMETERS
The following main.cf parameters are especially relevant to this pro-
gram.
The text below provides only a parameter summary. See postconf(5) for
more details including examples.
config_directory (see 'postconf -d' output)
The default location of the Postfix main.cf and master.cf config-
uration files.
bounce_template_file (empty)
Pathname of a configuration file with bounce message templates.
FILES
/etc/postfix/main.cf, Postfix configuration parameters
/etc/postfix/master.cf, Postfix master daemon configuration
SEE ALSO
bounce(5), bounce template file format
master(5), master.cf configuration file syntax
postconf(5), main.cf configuration file syntax
README FILES
Use "postconf readme_directory" or "postconf html_directory" to locate
this information.
DATABASE_README, Postfix lookup table overview
LICENSE
The Secure Mailer license must be distributed with this software.
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
POSTCONF(1)
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