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

NAME

       master - Postfix master process

SYNOPSIS

       master [-c config_dir] [-e exit_time] [-D] [-t] [-v]

DESCRIPTION

       The master daemon is the resident process that runs Postfix daemons on demand: daemons to send or receive messages via the network, daemons
       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. The exception to this rule is the resident Postfix queue manager.

       The  behavior  of the master daemon is controlled by the master.cf configuration file. The table specifies zero or more servers in the UNIX
       or INET domain, or servers that take requests from a FIFO. Precise configuration details are given in the master.cf file, and in the manual
       pages of the respective daemons.

       Options:

       -c config_dir
	      Read the main.cf and master.cf configuration files in the named directory instead of the default configuration directory.

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

       -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.

       -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 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 termi-
	      nates.  This is useful for an emergency shutdown. Normally one would terminate only the master (postfix stop) and allow running pro-
	      cesses to finish what they are doing.

DIAGNOSTICS

       Problems are reported to syslogd(8).

BUGS

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

       The  following  main.cf parameters are especially relevant to this program. See the Postfix main.cf file for syntax details and for default
       values. Use the postfix reload command after a configuration change.

Miscellaneous
       import_environment

       export_environment
	      Lists of names of environment parameters that can be imported from (exported to) non-Postfix processes.

       mail_owner
	      The owner of the mail queue and of most Postfix processes.

       command_directory
	      Directory with Postfix support programs.

       daemon_directory
	      Directory with Postfix daemon programs.

       queue_directory
	      Top-level directory of the Postfix queue. This is also the root directory of Postfix daemons that run chrooted.

Resource controls
       default_process_limit
	      Default limit for the number of simultaneous child processes that provide a given service.

       max_idle
	      Limit the time in seconds that a child process waits between service requests.

       max_use
	      Limit the number of service requests handled by a child process.

       service_throttle_time
	      Time to avoid forking a server that appears to be broken.

FILES

       /etc/postfix/main.cf: global configuration file.
       /etc/postfix/master.cf: master process configuration file.
       /var/spool/postfix/pid/master.pid: master lock file.

SEE ALSO

       qmgr(8) queue manager
       pickup(8) local mail pickup
       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)