1#++ 2# NAME 3# master 5 4# SUMMARY 5# Postfix master process configuration file format 6# DESCRIPTION 7# The Postfix mail system is implemented by small number of 8# (mostly) client commands that are invoked by users, and by 9# a larger number of services that run in the background. 10# 11# Postfix services are implemented by daemon processes. These 12# run in the background under control of the \fBmaster\fR(8) 13# process. The master.cf configuration file defines how a 14# client program connects to a service, and what daemon 15# program runs when a service is requested. Most daemon 16# processes are short-lived and terminate voluntarily after 17# serving \fBmax_use\fR clients, or after inactivity for 18# \fBmax_idle\fR or more units of time. 19# 20# All daemons specified here must speak a Postfix-internal 21# protocol. In order to execute non-Postfix software use the 22# \fBlocal\fR(8), \fBpipe\fR(8) or \fBspawn\fR(8) services, or 23# run the server under control by \fBinetd\fR(8) or equivalent. 24# .PP 25# After changing master.cf you must execute "\fBpostfix reload\fR" 26# to reload the configuration. 27# SYNTAX 28# .ad 29# .fi 30# The general format of the master.cf file is as follows: 31# .IP \(bu 32# Each logical line defines a single Postfix service. 33# Each service is identified by its name and type as described 34# below. When multiple lines specify the same service name 35# and type, only the last one is remembered. Otherwise, the 36# order of master.cf service definitions does not matter. 37# .IP \(bu 38# Empty lines and whitespace-only lines are ignored, as are 39# lines whose first non-whitespace character is a `#'. 40# .IP \(bu 41# A logical line starts with non-whitespace text. A line that 42# starts with whitespace continues a logical line. 43# .PP 44# Each logical line consists of eight fields separated by 45# whitespace. These are described below in the order as they 46# appear in the master.cf file. 47# 48# Where applicable a field of "-" requests that the built-in 49# default value be used. For boolean fields specify "y" or 50# "n" to override the default value. 51# .IP "\fBService name\fR" 52# The service name syntax depends on the service type as 53# described next. 54# .IP "\fBService type\fR" 55# Specify one of the following service types: 56# .RS 57# .IP \fBinet\fR 58# The service listens on a TCP/IP socket and is accessible 59# via the network. 60# 61# The service name is specified as \fIhost:port\fR, denoting 62# the host and port on which new connections should be 63# accepted. The host part (and colon) may be omitted. Either 64# host or port may be given in symbolic form (host or service 65# name) or in numeric form (IP address or port number). 66# Host information may be enclosed inside "[]", but this form 67# is not necessary. 68# .sp 69# Examples: a service named \fB127.0.0.1:smtp\fR or \fB::1:smtp\fR 70# receives 71# mail via the loopback interface only; and a service named 72# \fB10025\fR accepts connections on TCP port 10025 via 73# all interfaces configured with the \fBinet_interfaces\fR 74# parameter. 75# 76# .sp 77# Note: with Postfix version 2.2 and later specify 78# "\fBinet_interfaces = loopback-only\fR" in main.cf, instead 79# of hard-coding loopback IP address information in master.cf 80# or in main.cf. 81# .IP \fBunix\fR 82# The service listens on a UNIX-domain socket and is accessible 83# for local clients only. 84# 85# The service name is a pathname relative to the Postfix 86# queue directory (pathname controlled with the \fBqueue_directory\fR 87# configuration parameter in main.cf). 88# .sp 89# On Solaris systems the \fBunix\fR type is implemented with 90# streams sockets. 91# .IP \fBfifo\fR 92# The service listens on a FIFO (named pipe) and is accessible 93# for local clients only. 94# 95# The service name is a pathname relative to the Postfix 96# queue directory (pathname controlled with the \fBqueue_directory\fR 97# configuration parameter in main.cf). 98# .IP \fBpass\fR 99# The service listens on a UNIX-domain socket, and is accessible 100# to local clients only. It receives one open connection (file 101# descriptor passing) per connection request. 102# 103# The service name is a pathname relative to the Postfix 104# queue directory (pathname controlled with the \fBqueue_directory\fR 105# configuration parameter in main.cf). 106# .sp 107# On Solaris systems the \fBpass\fR type is implemented with 108# streams sockets. 109# 110# This feature is available as of Postfix version 2.5. 111# .RE 112# .IP "\fBPrivate (default: y)\fR" 113# Whether or not access is restricted to the mail system. 114# Internet (type \fBinet\fR) services can't be private. 115# .IP "\fBUnprivileged (default: y)\fR" 116# Whether the service runs with root privileges or as the 117# owner of the Postfix system (the owner name is controlled 118# by the \fBmail_owner\fR configuration variable in the 119# main.cf file). 120# .sp 121# The \fBlocal\fR(8), \fBpipe\fR(8), \fBspawn\fR(8), and 122# \fBvirtual\fR(8) daemons require privileges. 123# .IP "\fBChroot (default: y)\fR" 124# Whether or not the service runs chrooted to the mail queue 125# directory (pathname is controlled by the \fBqueue_directory\fR 126# configuration variable in the main.cf file). 127# .sp 128# Chroot should not be used with the \fBlocal\fR(8), 129# \fBpipe\fR(8), \fBspawn\fR(8), and \fBvirtual\fR(8) daemons. 130# Although the 131# \fBproxymap\fR(8) server can run chrooted, doing so defeats 132# most of the purpose of having that service in the first 133# place. 134# .sp 135# The files in the examples/chroot-setup subdirectory of the 136# Postfix source archive show set up a Postfix chroot environment 137# on a variety of systems. See also BASIC_CONFIGURATION_README 138# for issues related to running daemons chrooted. 139# .IP "\fBWake up time (default: 0)\fR" 140# Automatically wake up the named service after the specified 141# number of seconds. The wake up is implemented by connecting 142# to the service and sending a wake up request. A ? at the 143# end of the wake-up time field requests that no wake up 144# events be sent before the first time a service is used. 145# Specify 0 for no automatic wake up. 146# .sp 147# The \fBpickup\fR(8), \fBqmgr\fR(8) and \fBflush\fR(8) 148# daemons require a wake up timer. 149# .IP "\fBProcess limit (default: $default_process_limit)\fR" 150# The maximum number of processes that may execute this 151# service simultaneously. Specify 0 for no process count limit. 152# .sp 153# NOTE: Some Postfix services must be configured as a 154# single-process service (for example, \fBqmgr\fR(8)) and 155# some services must be configured with no process limit (for 156# example, \fBcleanup\fR(8)). These limits must not be 157# changed. 158# .IP "\fBCommand name + arguments\fR" 159# The command to be executed. Characters that are special 160# to the shell such as ">" or "|" have no special meaning 161# here, and quotes cannot be used to protect arguments 162# containing whitespace. 163# .sp 164# The command name is relative to the Postfix daemon directory 165# (pathname is controlled by the \fBdaemon_directory\fR 166# configuration variable). 167# .sp 168# The command argument syntax for specific commands is 169# specified in the respective daemon manual page. 170# .sp 171# The following command-line options have the same effect for 172# all daemon programs: 173# .RS 174# .IP \fB-D\fR 175# Run the daemon under control by the command specified with 176# the \fBdebugger_command\fR variable in the main.cf 177# configuration file. See DEBUG_README for hints and tips. 178# .IP "\fB-o \fIname\fR=\fIvalue\fR" 179# Override the named main.cf configuration parameter. The 180# parameter value can refer to other parameters as \fI$name\fR 181# etc., just like in main.cf. See \fBpostconf\fR(5) for 182# syntax. 183# .sp 184# NOTE 1: do not specify whitespace around the "=". In parameter 185# values, either avoid whitespace altogether, use commas 186# instead of spaces, or consider overrides like "-o 187# name=$override_parameter" with $override_parameter set in 188# main.cf. 189# .sp 190# NOTE 2: Over-zealous use of parameter overrides makes the 191# Postfix configuration hard to understand and maintain. At 192# a certain point, it might be easier to configure multiple 193# instances of Postfix, instead of configuring multiple 194# personalities via master.cf. 195# .IP \fB-v\fR 196# Increase the verbose logging level. Specify multiple \fB-v\fR 197# options to make a Postfix daemon process increasingly verbose. 198# SEE ALSO 199# master(8), process manager 200# postconf(5), configuration parameters 201# README FILES 202# .ad 203# .fi 204# Use "\fBpostconf readme_directory\fR" or 205# "\fBpostconf html_directory\fR" to locate this information. 206# .na 207# .nf 208# BASIC_CONFIGURATION_README, basic configuration 209# DEBUG_README, Postfix debugging 210# LICENSE 211# .ad 212# .fi 213# The Secure Mailer license must be distributed with this software. 214# AUTHOR(S) 215# Initial version by 216# Magnus Baeck 217# Lund Institute of Technology 218# Sweden 219# 220# Wietse Venema 221# IBM T.J. Watson Research 222# P.O. Box 704 223# Yorktown Heights, NY 10598, USA 224#-- 225