""> MASTER(8) MASTER(8) NAME master - Postfix master process SYNOPSIS master [-Dtv] [-c config_dir] [-e exit_time] DESCRIPTION The master daemon is the resident process that runs Post- fix 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. Exceptions to this rule are the resident queue manager and the resident address verification server. The behavior of the master daemon is controlled by the 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 file, and in the manual pages of the respective daemons. Options: -c config_dir Read the and configuration files in the named directory instead of the default con- figuration directory. -e exit_time Terminate the master process after exit_time sec- onds. Child processes terminate at their conve- nience. -D After initialization, run a debugger on the master process. The debugging command is specified with the debugger_command in the global configu- ration file. -t Test mode. Return a zero exit status when the mas- 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 configura- tion files. If a service has been removed from the file, its running processes are termi- nated 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 terminates. This is useful for an emergency shutdown. Normally one would ter- minate 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 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 Changes to are never picked up automatically. Use the postfix reload command after a configuration change. RESOURCE AND RATE CONTROLS daemon_timeout (18000s) How much time a Postfix daemon process may take to handle a request before it is terminated by a built-in watchdog timer. default_process_limit (100) The default maximal number of Postfix child pro- cesses that provide a given service. max_idle (100s) The maximum amount of time that an idle Postfix daemon process waits for the next service request before exiting. max_use (100) The maximal number of connection requests before a Postfix daemon process terminates. service_throttle_time (60s) How long the Postfix master(8) waits before forking a server that appears to be malfunctioning. MISCELLANEOUS CONTROLS config_directory (see 'postconf -d' output) The default location of the Postfix and 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 dae- mon program is invoked with the -D option. inet_interfaces (all) The network interface addresses that this mail sys- tem receives mail on. import_environment (see 'postconf -d' output) The list of environment parameters that a Postfix process will import from a non-Postfix parent pro- cess. 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 pro- cess. 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 direc- tory. syslog_facility (mail) The syslog facility of Postfix logging. syslog_name (postfix) The mail system name that is prepended to the pro- cess name in syslog records, so that "smtpd" becomes, for example, "postfix/smtpd". FILES /usr/local/etc/postfix/, global configuration file. /usr/local/etc/postfix/, master server configuration file. /var/spool/postfix/pid/, master lock file. SEE ALSO qmgr(8), queue manager verify(8), address verification postconf(5), configuration parameters 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)