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.

   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
          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

   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 and  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
          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 and 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.


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

   config_directory (see 'postconf -d' output)
          The default  location  of  the  Postfix  and
          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:

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

   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

   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 parameters that a Postfix process will
          import from a non-Postfix parent process.

   syslog_facility (mail)
          The syslog facility of Postfix logging.

   syslog_name (see 'postconf -d' output)
          The mail system name that is prepended to the  process  name  in
          syslog   records,   so   that   "smtpd"  becomes,  for  example,

   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.


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

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

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


   postalias(1), create/update/query alias database
   postcat(1), examine Postfix queue file
   postconf(1), Postfix configuration 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 file syntax
   postconf(5), Postfix 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 black/whitelist 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
   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



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