MASTER(8)						      System Manager's Manual							 MASTER(8)

NAME

       master - Postfix master process

SYNOPSIS

       master [-Ddtv] [-c config_dir] [-e exit_time]

DESCRIPTION

       The master(8) daemon is the resident process that runs Postfix daemons on demand: daemons to send or receive messages via the network, dae-
       mons to deliver mail locally, etc.  These daemons are created on demand up to a configurable maximum number per service.

       Postfix daemons terminate voluntarily, either after being idle for a configurable amount of time, or after having serviced  a  configurable
       number  of  requests.  Exceptions  to  this rule are the resident queue manager, address verification server, and the TLS session cache and
       pseudo-random number server.

       The behavior of the master(8) daemon is controlled by the master.cf configuration file, as described in master(5).

       Options:

       -c config_dir
	      Read the main.cf and master.cf configuration files in the named directory instead of the default configuration directory.  This also
	      overrides the configuration files for other Postfix daemon processes.

       -D     After  initialization,  run  a  debugger	on the master process. The debugging command is specified with the debugger_command in the
	      main.cf global configuration file.

       -d     Do not redirect stdin, stdout or stderr to /dev/null, and do not discard the controlling terminal. This must be used  for  debugging
	      only.

       -e exit_time
	      Terminate the master process after exit_time seconds. Child processes terminate at their convenience.

       -t     Test mode. Return a zero exit status when the master.pid lock file does not exist or when that file is not locked.  This is evidence
	      that the master(8) daemon is not running.

       -v     Enable verbose logging for debugging purposes. This option is passed on to child processes. Multiple -v options  make  the  software
	      increasingly verbose.

       Signals:

       SIGHUP Upon  receipt  of a HUP signal (e.g., after "postfix reload"), the master process re-reads its configuration files. If a service has
	      been removed from the master.cf file, its running processes are terminated immediately.  Otherwise, running processes are allowed to
	      terminate as soon as is convenient, so that changes in configuration settings affect only new service requests.

       SIGTERM
	      Upon receipt of a TERM signal (e.g., after "postfix abort"), the master process passes the signal on to its child processes and ter-
	      minates.	This is useful for an emergency shutdown. Normally one would terminate only the master ("postfix stop") and allow  running
	      processes to finish what they are doing.

DIAGNOSTICS

       Problems are reported to syslogd(8).

ENVIRONMENT

       MAIL_DEBUG
	      After  initialization,  start a debugger as specified with the debugger_command configuration parameter in the main.cf configuration
	      file.

       MAIL_CONFIG
	      Directory with Postfix configuration files.

CONFIGURATION PARAMETERS

       Unlike most Postfix daemon processes, the master(8) server does not automatically pick up changes to  main.cf.  Changes	to  master.cf  are
       never picked up automatically.  Use the "postfix reload" command after a configuration change.

RESOURCE AND RATE CONTROLS

       default_process_limit (100)
	      The default maximal number of Postfix child processes that provide a given service.

       max_idle (100s)
	      The maximum amount of time that an idle Postfix daemon process waits for an incoming connection before terminating voluntarily.

       max_use (100)
	      The maximal number of incoming connections that a Postfix daemon process will service before terminating voluntarily.

       service_throttle_time (60s)
	      How long the Postfix master(8) waits before forking a server that appears to be malfunctioning.

       Available in Postfix version 2.6 and later:

       master_service_disable (empty)
	      Selectively disable master(8) listener ports by service type or by service name and type.

MISCELLANEOUS CONTROLS

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

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

       debugger_command (empty)
	      The external command to execute when a Postfix daemon program is invoked with the -D option.

       inet_interfaces (all)
	      The network interface addresses that this mail system receives mail on.

       inet_protocols (ipv4)
	      The Internet protocols Postfix will attempt to use when making or accepting connections.

       import_environment (see 'postconf -d' output)
	      The list of environment parameters that a Postfix process will import from a non-Postfix parent process.

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

       process_id (read-only)
	      The process ID of a Postfix command or daemon process.

       process_name (read-only)
	      The process name of a Postfix command or daemon process.

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

       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, "postfix/smtpd".

FILES

       To expand the directory names below into their actual values, use the command "postconf config_directory" etc.

       $config_directory/main.cf, global configuration file.
       $config_directory/master.cf, master server configuration file.
       $queue_directory/pid/master.pid, master lock file.
       $data_directory/master.lock, master lock file.

SEE ALSO

       qmgr(8), queue manager
       verify(8), address verification
       master(5), master.cf configuration file syntax
       postconf(5), main.cf configuration parameter syntax
       syslogd(8), system logging

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

																	 MASTER(8)