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POSTFIX(1)                  General Commands Manual                 POSTFIX(1)

       postfix - Postfix control program

       postfix [-Dv] [-c config_dir] command

       This command is reserved for the superuser. To submit mail, use the
       Postfix sendmail(1) command.

       The postfix(1) command controls the operation of the Postfix mail
       system: start or stop the master(8) daemon, do a health check, and
       other maintenance.

       By default, the postfix(1) command sets up a standardized environment
       and runs the postfix-script shell script to do the actual work.

       However, when support for multiple Postfix instances is configured,
       postfix(1) executes the command specified with the
       multi_instance_wrapper configuration parameter.  This command will
       execute the command for each applicable Postfix instance.

       The following commands are implemented:

       check  Warn about bad directory/file ownership or permissions, and
              create missing directories.

       start  Start the Postfix mail system. This also runs the configuration
              check described above.

              Like start, but keep the master(8) daemon running in the
              foreground, and enable master(8) "init" mode when running as PID
              1.  This command requires that multi-instance support is
              disabled (i.e. the multi_instance_directories parameter value
              must be empty).

              When running Postfix inside a container, see MAILLOG_README for
              logging to stdout. Postfix logs to syslog by default, which
              requires a) running a syslogd process inside the container, or
              b) mounting the container host's /dev/log socket inside the
              container (example: "docker run -v /dev/log:/dev/log ..."), and
              c) a distinct Postfix "syslog_name" prefix that identifies
              logging from the Postfix instance.

       stop   Stop the Postfix mail system in an orderly fashion. If possible,
              running processes are allowed to terminate at their earliest

              Note: in order to refresh the Postfix mail system after a
              configuration change, do not use the start and stop commands in
              succession. Use the reload command instead.

       abort  Stop the Postfix mail system abruptly. Running processes are
              signaled to stop immediately.

       flush  Force delivery: attempt to deliver every message in the deferred
              mail queue. Normally, attempts to deliver delayed mail happen at
              regular intervals, the interval doubling after each failed

              Warning: flushing undeliverable mail frequently will result in
              poor delivery performance of all other mail.

       reload Re-read configuration files. Running processes terminate at
              their earliest convenience.

       status Indicate if the Postfix mail system is currently running.

       set-permissions [name=value ...]
              Set the ownership and permissions of Postfix related files and
              directories, as specified in the postfix-files file.

              Specify name=value to override and update specific main.cf
              configuration parameters. Use this, for example, to change the
              mail_owner or setgid_group setting for an already installed
              Postfix system.

              This feature is available in Postfix 2.1 and later.  With
              Postfix 2.0 and earlier, use "$config_directory/post-install

              Rotate the logfile specified with $maillog_file, by appending a
              time-stamp suffix that is formatted according to
              $maillog_file_rotate_suffix, and by compressing the file with
              the command specified with $maillog_file_compressor.  This will
              not rotate /dev/* files.

              This feature is available in Postfix 3.4 and later.

       tls subcommand
              Enable opportunistic TLS in the Postfix SMTP client or server,
              and manage Postfix SMTP server TLS private keys and
              certificates.  See postfix-tls(1) for documentation.

              This feature is available in Postfix 3.1 and later.

       upgrade-configuration [name=value ...]
              Update the main.cf and master.cf files with information that
              Postfix needs in order to run: add or update services, and add
              or update configuration parameter settings.

              Specify name=value to override and update specific main.cf
              configuration parameters.

              This feature is available in Postfix 2.1 and later.  With
              Postfix 2.0 and earlier, use "$config_directory/post-install

       The following options are implemented:

       -c config_dir
              Read the main.cf and master.cf configuration files in the named
              directory instead of the default configuration directory.  Use
              this to distinguish between multiple Postfix instances on the
              same host.

              With Postfix 2.6 and later, this option forces the postfix(1)
              command to operate on the specified Postfix instance only.  This
              behavior is inherited by postfix(1) commands that run as a
              descendant of the current process.

       -D (with postfix start only)
              Run each Postfix daemon under control of a debugger as specified
              via the debugger_command configuration parameter.

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

       The postfix(1) command exports the following environment variables
       before executing the postfix-script file:

              This is set when the -c command-line option is present.

              With Postfix 2.6 and later, this environment variable forces the
              postfix(1) command to operate on the specified Postfix instance
              only.  This behavior is inherited by postfix(1) commands that
              run as a descendant of the current process.

              This is set when the -v command-line option is present.

              This is set when the -D command-line option is present.

       When the internal logging service is enabled (by setting a non-empty
       maillog_file parameter value) the postfix(1) command exports settings
       that are used by child processes before they have processed main.cf or
       command-line settings.

              The name of the public postlog service endpoint.

              The hostname to prepend to internal logging.

       The following main.cf configuration parameters are exported as
       environment variables with the same names:

       config_directory (see 'postconf -d' output)
              The default location of the Postfix main.cf and master.cf
              configuration files.

       command_directory (see 'postconf -d' output)
              The location of all postfix administrative commands.

       daemon_directory (see 'postconf -d' output)
              The directory with Postfix support programs and daemon programs.

       html_directory (see 'postconf -d' output)
              The location of Postfix HTML files that describe how to build,
              configure or operate a specific Postfix subsystem or feature.

       mail_owner (postfix)
              The UNIX system account that owns the Postfix queue and most
              Postfix daemon processes.

       mailq_path (see 'postconf -d' output)
              Sendmail compatibility feature that specifies where the Postfix
              mailq(1) command is installed.

       manpage_directory (see 'postconf -d' output)
              Where the Postfix manual pages are installed.

       newaliases_path (see 'postconf -d' output)
              Sendmail compatibility feature that specifies the location of
              the newaliases(1) command.

       queue_directory (see 'postconf -d' output)
              The location of the Postfix top-level queue directory.

       readme_directory (see 'postconf -d' output)
              The location of Postfix README files that describe how to build,
              configure or operate a specific Postfix subsystem or feature.

       sendmail_path (see 'postconf -d' output)
              A Sendmail compatibility feature that specifies the location of
              the Postfix sendmail(1) command.

       setgid_group (postdrop)
              The group ownership of set-gid Postfix commands and of
              group-writable Postfix directories.

       Available in Postfix version 2.5 and later:

       data_directory (see 'postconf -d' output)
              The directory with Postfix-writable data files (for example:
              caches, pseudo-random numbers).

       Available in Postfix version 3.0 and later:

       compatibility_level (0)
              A safety net that causes Postfix to run with
              backwards-compatible default settings after an upgrade to a
              newer Postfix version.

       meta_directory (see 'postconf -d' output)
              The location of non-executable files that are shared among
              multiple Postfix instances, such as postfix-files,
              dynamicmaps.cf, and the multi-instance template files
              main.cf.proto and master.cf.proto.

       shlib_directory (see 'postconf -d' output)
              The location of Postfix dynamically-linked libraries
              (libpostfix-*.so), and the default location of Postfix database
              plugins (postfix-*.so) that have a relative pathname in the
              dynamicmaps.cf file.

       Available in Postfix version 3.1 and later:

       openssl_path (openssl)
              The location of the OpenSSL command line program openssl(1).

       Other configuration parameters:

       import_environment (see 'postconf -d' output)
              The list of environment variables that a privileged Postfix
              process will import from a non-Postfix parent process, or
              name=value environment overrides.

       syslog_facility (mail)
              The syslog facility of Postfix logging.

       syslog_name (see 'postconf -d' output)
              A prefix that is prepended to the process name in syslog
              records, so that, for example, "smtpd" becomes "prefix/smtpd".

       Available in Postfix version 2.6 and later:

       multi_instance_directories (empty)
              An optional list of non-default Postfix configuration
              directories; these directories belong to additional Postfix
              instances that share the Postfix executable files and
              documentation with the default Postfix instance, and that are
              started, stopped, etc., together with the default Postfix

       multi_instance_wrapper (empty)
              The pathname of a multi-instance manager command that the
              postfix(1) command invokes when the multi_instance_directories
              parameter value is non-empty.

       multi_instance_group (empty)
              The optional instance group name of this Postfix instance.

       multi_instance_name (empty)
              The optional instance name of this Postfix instance.

       multi_instance_enable (no)
              Allow this Postfix instance to be started, stopped, etc., by a
              multi-instance manager.

       Available in Postfix version 3.4 and later:

       maillog_file (empty)
              The name of an optional logfile that is written by the Postfix
              postlogd(8) service.

       maillog_file_compressor (gzip)
              The program to run after rotating $maillog_file with "postfix

       maillog_file_prefixes (/var, /dev/stdout)
              A list of allowed prefixes for a maillog_file value.

       maillog_file_rotate_suffix (%Y%m%d-%H%M%S)
              The format of the suffix to append to $maillog_file while
              rotating the file with "postfix logrotate".

       postlog_service_name (postlog)
              The name of the postlogd(8) service entry in master.cf.

       Prior to Postfix version 2.6, all of the following files were in
       $config_directory. Some files are now in $daemon_directory or
       $meta_directory so that they can be shared among multiple instances
       that run the same Postfix version.

       Use the command "postconf config_directory" or "postconf
       daemon_directory" to expand the names into their actual values.

       $config_directory/main.cf, Postfix configuration parameters
       $config_directory/master.cf, Postfix daemon processes
       $daemon_directory/postfix-script, administrative commands
       $daemon_directory/post-install, post-installation configuration
       $meta_directory/dynamicmaps.cf, plug-in database clients
       $meta_directory/postfix-files, file/directory permissions

       postalias(1), create/update/query alias database
       postcat(1), examine Postfix queue file
       postconf(1), Postfix configuration utility
       postdrop(1), Postfix mail posting utility
       postfix(1), Postfix control program
       postfix-tls(1), Postfix TLS management
       postkick(1), trigger Postfix daemon
       postlock(1), Postfix-compatible locking
       postlog(1), Postfix-compatible logging
       postmap(1), Postfix lookup table manager
       postmulti(1), Postfix multi-instance manager
       postqueue(1), Postfix mail queue control
       postsuper(1), Postfix housekeeping
       mailq(1), Sendmail compatibility interface
       newaliases(1), Sendmail compatibility interface
       sendmail(1), Sendmail compatibility interface

       Postfix configuration:
       bounce(5), Postfix bounce message templates
       master(5), Postfix master.cf file syntax
       postconf(5), Postfix main.cf file syntax
       postfix-wrapper(5), Postfix multi-instance API

       Table-driven mechanisms:
       access(5), Postfix SMTP access control table
       aliases(5), Postfix alias database
       canonical(5), Postfix input address rewriting
       generic(5), Postfix output address rewriting
       header_checks(5), body_checks(5), Postfix content inspection
       relocated(5), Users that have moved
       transport(5), Postfix routing table
       virtual(5), Postfix virtual aliasing

       Table lookup mechanisms:
       cidr_table(5), Associate CIDR pattern with value
       ldap_table(5), Postfix LDAP client
       lmdb_table(5), Postfix LMDB database driver
       memcache_table(5), Postfix memcache client
       mysql_table(5), Postfix MYSQL client
       nisplus_table(5), Postfix NIS+ client
       pcre_table(5), Associate PCRE pattern with value
       pgsql_table(5), Postfix PostgreSQL client
       regexp_table(5), Associate POSIX regexp pattern with value
       socketmap_table(5), Postfix socketmap client
       sqlite_table(5), Postfix SQLite database driver
       tcp_table(5), Postfix client-server table lookup

       Daemon processes:
       anvil(8), Postfix connection/rate limiting
       bounce(8), defer(8), trace(8), Delivery status reports
       cleanup(8), canonicalize and enqueue message
       discard(8), Postfix discard delivery agent
       dnsblog(8), DNS allow/denylist logger
       error(8), Postfix error delivery agent
       flush(8), Postfix fast ETRN service
       local(8), Postfix local delivery agent
       master(8), Postfix master daemon
       oqmgr(8), old Postfix queue manager
       pickup(8), Postfix local mail pickup
       pipe(8), deliver mail to non-Postfix command
       postlogd(8), Postfix internal logging service
       postscreen(8), Postfix zombie blocker
       proxymap(8), Postfix lookup table proxy server
       qmgr(8), Postfix queue manager
       qmqpd(8), Postfix QMQP server
       scache(8), Postfix connection cache manager
       showq(8), list Postfix mail queue
       smtp(8), lmtp(8), Postfix SMTP+LMTP client
       smtpd(8), Postfix SMTP server
       spawn(8), run non-Postfix server
       tlsmgr(8), Postfix TLS cache and randomness manager
       tlsproxy(8), Postfix TLS proxy server
       trivial-rewrite(8), Postfix address rewriting
       verify(8), Postfix address verification
       virtual(8), Postfix virtual delivery agent

       syslogd(8), system logging

       Use "postconf readme_directory" or "postconf html_directory" to locate
       this information.
       OVERVIEW, overview of Postfix commands and processes
       BASIC_CONFIGURATION_README, Postfix basic configuration
       ADDRESS_REWRITING_README, Postfix address rewriting
       SMTPD_ACCESS_README, SMTP relay/access control
       CONTENT_INSPECTION_README, Postfix content inspection
       QSHAPE_README, Postfix queue analysis

       The Secure Mailer license must be distributed with this software.

       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

       TLS support by:
       Lutz Jaenicke
       Brandenburg University of Technology
       Cottbus, Germany

       Victor Duchovni
       Morgan Stanley

       SASL support originally by:
       Till Franke
       SuSE Rhein/Main AG
       65760 Eschborn, Germany

       LMTP support originally by:
       Philip A. Prindeville
       Mirapoint, Inc.

       Amos Gouaux
       University of Texas at Dallas
       P.O. Box 830688, MC34
       Richardson, TX 75083, USA

       IPv6 support originally by:
       Mark Huizer, Eindhoven University, The Netherlands
       Jun-ichiro 'itojun' Hagino, KAME project, Japan
       The Linux PLD project
       Dean Strik, Eindhoven University, The Netherlands