POSTCONF(1)

NAME
postconf - Postfix configuration utility

SYNOPSIS
postconf [-dhnv] [-c config_dir] [parameter ...] postconf [-aAmlv] [-c config_dir] postconf [-ev] [-c config_dir] [parameter=value ...] postconf [-#v] [-c config_dir] [parameter ...] postconf [-btv] [-c config_dir] [template_file]

DESCRIPTION
The postconf(1) command displays the actual values of configuration parameters, changes configuration parameter values, or displays other configuration information about the Postfix mail system. Options:

-a  List the available SASL server plug-in types. The SASL plug-in type is selected with the smtpd_sasl_type configuration parameter by specifying one of the names listed below.

    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 client plug-in types. The SASL 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 delivery status notification (DSN) messages, with $name expressions replaced by actual values. To override the built-in message text, specify a template file at the end of the command line, or specify a template file in main.cf with the bounce_template_file parameter. To force selection of the built-in message text templates, specify an empty template file name (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.

-d  Print default parameter settings instead of actual settings.

-e  Edit the main.cf configuration file. The file is copied to a temporary file then renamed into place. Parameters and values are specified on the command line. Use quotes in order to protect shell metacharacters and whitespace.

-h  Show parameter values only, not the ``name = '' label that normally precedes the value.

-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 remote files.

    dotlock
        An application-level locking method. An application locks a file named filename by creating a file named filename.lock. The application is expected to remove its own lock file, as well as stale lock files that were left behind after abnormal 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 syntax depends on the lookup table type as described in the DATABASE_README document.

    btree
        A sorted, balanced tree structure. This is available on systems with support for Berkeley DB databases.

    cdb A read-optimized structure with no support for incremental updates. This is available on systems with support for CDB databases.

    cidr
        A table that associates values with Classless Inter-Domain Routing (CIDR) patterns. This is described in cidr_table(5).

    dbm An indexed file type based on hashing. This is available on systems with support for DBM databases.

    environ
        The UNIX process environment array. The lookup key is the variable name. Originally implemented for testing, someone may find this useful someday.

    hash
        An indexed file type based on hashing. This is available on systems with support for Berkeley DB databases.

    ldap (read-only)
        Perform lookups using the LDAP protocol. This is described in ldap_table(5).

    mysql (read-only)
        Perform lookups using the MYSQL protocol. This is described in mysql_table(5).

    pcre (read-only)
        A lookup table based on Perl Compatible Regular Expressions. The file format is described in pcre_table(5).

    pgsql (read-only)
        Perform lookups using the PostgreSQL protocol. This is described in pgsql_table(5).

    proxy (read-only)
        A lookup table that is implemented via the Postfix proxymap(8) service. The table name syntax is type:name.

    regexp (read-only)
        A lookup table based on regular expressions. The file format is described in regexp_table(5).

    sdbm
        An indexed file type based on hashing. This is available on systems with support for SDBM databases.

    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.

    tcp (read-only)
        Perform lookups using a simple request-reply protocol that is described in tcp_table(5). This feature is not included with the stable Postfix release.

    unix (read-only)
        A limited way to query 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.

-n  Print parameter settings that are not left at their built-in default value, because they are explicitly specified in main.cf.

-t [template_file]
    Display the templates for delivery status notification (DSN) messages. To override the built-in templates, specify a template file at the end of the command line, or specify a template file in main.cf with the bounce_template_file parameter. To force selection of the built-in templates, specify an empty template file name (in shell language: ""). This feature is available with Postfix 2.3 and later.

-v  Enable verbose logging for debugging purposes. Multiple -v options make the software increasingly verbose.

-#  Edit the main.cf configuration file. The file is copied to a temporary file then renamed into place. The parameters specified on the command line are commented-out, so that they revert to their default values. Specify a list of parameter names, not name=value pairs. There is no postconf command to perform the reverse operation. This feature is available with Postfix 2.6 and later.

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 program. 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 configuration files.

bounce_template_file (empty)
    Pathname of a configuration file with bounce message templates.

FILES
/etc/postfix/main.cf, Postfix configuration parameters

SEE ALSO
bounce(5), bounce template file format
postconf(5), configuration parameters

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