1<!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" 2 "http://www.w3.org/TR/html4/loose.dtd"> 3<html> <head> 4<meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> 5<title> Postfix manual - master(5) </title> 6</head> <body> <pre> 7MASTER(5) MASTER(5) 8 9<b>NAME</b> 10 master - Postfix master process configuration file format 11 12<b>DESCRIPTION</b> 13 The Postfix mail system is implemented by small number of (mostly) 14 client commands that are invoked by users, and by a larger number of 15 services that run in the background. 16 17 Postfix services are implemented by daemon processes. These run in the 18 background under control of the <a href="master.8.html"><b>master</b>(8)</a> process. The <a href="master.5.html">master.cf</a> con- 19 figuration file defines how a client program connects to a service, and 20 what daemon program runs when a service is requested. Most daemon pro- 21 cesses are short-lived and terminate voluntarily after serving <b><a href="postconf.5.html#max_use">max_use</a></b> 22 clients, or after inactivity for <b><a href="postconf.5.html#max_idle">max_idle</a></b> or more units of time. 23 24 All daemons specified here must speak a Postfix-internal protocol. In 25 order to execute non-Postfix software use the <a href="local.8.html"><b>local</b>(8)</a>, <a href="pipe.8.html"><b>pipe</b>(8)</a> or 26 <a href="spawn.8.html"><b>spawn</b>(8)</a> services, or run the server under control by <b>inetd</b>(8) or 27 equivalent. 28 29 After changing <a href="master.5.html">master.cf</a> you must execute "<b>postfix reload</b>" to reload 30 the configuration. 31 32<b>SYNTAX</b> 33 The general format of the <a href="master.5.html">master.cf</a> file is as follows: 34 35 <b>o</b> Empty lines and whitespace-only lines are ignored, as are lines 36 whose first non-whitespace character is a `#'. 37 38 <b>o</b> A logical line starts with non-whitespace text. A line that 39 starts with whitespace continues a logical line. 40 41 <b>o</b> Each logical line defines a single Postfix service. Each ser- 42 vice is identified by its name and type as described below. 43 When multiple lines specify the same service name and type, only 44 the last one is remembered. Otherwise, the order of <a href="master.5.html">master.cf</a> 45 service definitions does not matter. 46 47 Each logical line consists of eight fields separated by whitespace. 48 These are described below in the order as they appear in the <a href="master.5.html">master.cf</a> 49 file. 50 51 Where applicable a field of "-" requests that the built-in default 52 value be used. For boolean fields specify "y" or "n" to override the 53 default value. 54 55 <b>Service name</b> 56 The service name syntax depends on the service type as described 57 next. 58 59 <b>Service type</b> 60 Specify one of the following service types: 61 62 <b>inet</b> The service listens on a TCP/IP socket and is accessible 63 via the network. 64 65 The service name is specified as <i>host:port</i>, denoting the 66 host and port on which new connections should be 67 accepted. The host part (and colon) may be omitted. 68 Either host or port may be given in symbolic form (see 69 <b>hosts</b>(5) or <b>services</b>(5)) or in numeric form (IP address 70 or port number). Host information may be enclosed inside 71 "[]"; this form is necessary only with IPv6 addresses. 72 73 Examples: a service named <b>127.0.0.1:smtp</b> or <b>::1:smtp</b> 74 receives mail via the loopback interface only; and a ser- 75 vice named <b>10025</b> accepts connections on TCP port 10025 76 via all interfaces configured with the <b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a></b> 77 parameter. 78 79 Note: with Postfix version 2.2 and later specify 80 "<b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a> = loopback-only</b>" in <a href="postconf.5.html">main.cf</a>, instead of 81 hard-coding loopback IP address information in <a href="master.5.html">master.cf</a> 82 or in <a href="postconf.5.html">main.cf</a>. 83 84 <b>unix</b> The service listens on a UNIX-domain stream socket and is 85 accessible for local clients only. 86 87 The service name is a pathname relative to the Postfix 88 queue directory (pathname controlled with the 89 <b><a href="postconf.5.html#queue_directory">queue_directory</a></b> configuration parameter in <a href="postconf.5.html">main.cf</a>). 90 91 On Solaris 8 and earlier systems the <b>unix</b> type is imple- 92 mented with streams sockets. 93 94 <b>unix-dgram</b> 95 The service listens on a UNIX-domain datagram socket and 96 is accessible for local clients only. 97 98 The service name is a pathname relative to the Postfix 99 queue directory (pathname controlled with the 100 <b><a href="postconf.5.html#queue_directory">queue_directory</a></b> configuration parameter in <a href="postconf.5.html">main.cf</a>). 101 102 <b>fifo</b> (obsolete) 103 The service listens on a FIFO (named pipe) and is acces- 104 sible for local clients only. 105 106 The service name is a pathname relative to the Postfix 107 queue directory (pathname controlled with the 108 <b><a href="postconf.5.html#queue_directory">queue_directory</a></b> configuration parameter in <a href="postconf.5.html">main.cf</a>). 109 110 <b>pass</b> The service listens on a UNIX-domain stream socket, and 111 is accessible to local clients only. It receives one open 112 connection (file descriptor passing) per connection 113 request. 114 115 The service name is a pathname relative to the Postfix 116 queue directory (pathname controlled with the 117 <b><a href="postconf.5.html#queue_directory">queue_directory</a></b> configuration parameter in <a href="postconf.5.html">main.cf</a>). 118 119 On Solaris 8 and earlier systems the <b>pass</b> type is imple- 120 mented with streams sockets. 121 122 This feature is available as of Postfix version 2.5. 123 124 <b>Private (default: y)</b> 125 Whether or not access is restricted to the mail system. Inter- 126 net (type <b>inet</b>) services can't be private. 127 128 <b>Unprivileged (default: y)</b> 129 Whether the service runs with root privileges or as the owner of 130 the Postfix system (the owner name is controlled by the 131 <b><a href="postconf.5.html#mail_owner">mail_owner</a></b> configuration variable in the <a href="postconf.5.html">main.cf</a> file). 132 133 The <a href="local.8.html"><b>local</b>(8)</a>, <a href="pipe.8.html"><b>pipe</b>(8)</a>, <a href="spawn.8.html"><b>spawn</b>(8)</a>, and <a href="virtual.8.html"><b>virtual</b>(8)</a> daemons require 134 privileges. 135 136 <b>Chroot (default: Postfix</b> ><b>= 3.0: n, Postfix</b> <<b>3.0: y)</b> 137 Whether or not the service runs chrooted to the mail queue 138 directory (pathname is controlled by the <b><a href="postconf.5.html#queue_directory">queue_directory</a></b> config- 139 uration variable in the <a href="postconf.5.html">main.cf</a> file). 140 141 Chroot should not be used with the <a href="local.8.html"><b>local</b>(8)</a>, <a href="pipe.8.html"><b>pipe</b>(8)</a>, <a href="spawn.8.html"><b>spawn</b>(8)</a>, 142 and <a href="virtual.8.html"><b>virtual</b>(8)</a> daemons. Although the <a href="proxymap.8.html"><b>proxymap</b>(8)</a> server can run 143 chrooted, doing so defeats most of the purpose of having that 144 service in the first place. 145 146 The files in the examples/chroot-setup subdirectory of the Post- 147 fix source show how to set up a Postfix chroot environment on a 148 variety of systems. See also <a href="BASIC_CONFIGURATION_README.html">BASIC_CONFIGURATION_README</a> for 149 issues related to running daemons chrooted. 150 151 <b>Wake up time (default: 0)</b> 152 Automatically wake up the named service after the specified num- 153 ber of seconds. The wake up is implemented by connecting to the 154 service and sending a wake up request. A ? at the end of the 155 wake-up time field requests that no wake up events be sent 156 before the first time a service is used. Specify 0 for no auto- 157 matic wake up. 158 159 The <a href="pickup.8.html"><b>pickup</b>(8)</a>, <a href="qmgr.8.html"><b>qmgr</b>(8)</a> and <a href="flush.8.html"><b>flush</b>(8)</a> daemons require a wake up 160 timer. 161 162 <b>Process limit (default: $<a href="postconf.5.html#default_process_limit">default_process_limit</a>)</b> 163 The maximum number of processes that may execute this service 164 simultaneously. Specify 0 for no process count limit. 165 166 NOTE: Some Postfix services must be configured as a sin- 167 gle-process service (for example, <a href="qmgr.8.html"><b>qmgr</b>(8)</a>) and some services 168 must be configured with no process limit (for example, 169 <a href="cleanup.8.html"><b>cleanup</b>(8)</a>). These limits must not be changed. 170 171 <b>Command name + arguments</b> 172 The command to be executed. Characters that are special to the 173 shell such as ">" or "|" have no special meaning here, and 174 quotes cannot be used to protect arguments containing white- 175 space. To protect whitespace, use "{" and "}" as described 176 below. 177 178 The command name is relative to the Postfix daemon directory 179 (pathname is controlled by the <b><a href="postconf.5.html#daemon_directory">daemon_directory</a></b> configuration 180 variable). 181 182 The command argument syntax for specific commands is specified 183 in the respective daemon manual page. 184 185 The following command-line options have the same effect for all 186 daemon programs: 187 188 <b>-D</b> Run the daemon under control by the command specified 189 with the <b><a href="postconf.5.html#debugger_command">debugger_command</a></b> variable in the <a href="postconf.5.html">main.cf</a> config- 190 uration file. See <a href="DEBUG_README.html">DEBUG_README</a> for hints and tips. 191 192 <b>-o {</b> <i>name</i> = <i>value</i> <b>}</b> (long form, Postfix >= 3.0) 193 194 <b>-o</b> <i>name</i>=<i>value</i> (short form) 195 Override the named <a href="postconf.5.html">main.cf</a> configuration parameter. The 196 parameter value can refer to other parameters as <i>$name</i> 197 etc., just like in <a href="postconf.5.html">main.cf</a>. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for syntax. 198 199 NOTE 1: With the "long form" shown above, whitespace 200 after "{", around "=", and before "}" is ignored, and 201 whitespace within the parameter value is preserved. 202 203 NOTE 2: with the "short form" shown above, do not specify 204 whitespace around the "=" or in parameter values. To 205 specify a parameter value that contains whitespace, use 206 the long form described above, or use commas instead of 207 spaces, or specify the value in <a href="postconf.5.html">main.cf</a>. Example: 208 209 /etc/postfix/<a href="master.5.html">master.cf</a>: 210 submission inet .... smtpd 211 -o smtpd_xxx_yyy=$submission_xxx_yyy 212 213 /etc/postfix/<a href="postconf.5.html">main.cf</a> 214 submission_xxx_yyy = text with whitespace... 215 216 NOTE 3: Over-zealous use of parameter overrides makes the 217 Postfix configuration hard to understand and maintain. 218 At a certain point, it might be easier to configure mul- 219 tiple instances of Postfix, instead of configuring multi- 220 ple personalities via <a href="master.5.html">master.cf</a>. 221 222 <b>-v</b> Increase the verbose logging level. Specify multiple <b>-v</b> 223 options to make a Postfix daemon process increasingly 224 verbose. 225 226 Other command-line arguments 227 Specify "{" and "}" around command arguments that contain 228 whitespace (Postfix 3.0 and later). Whitespace after "{" 229 and before "}" is ignored. 230 231<b>SEE ALSO</b> 232 <a href="master.8.html">master(8)</a>, process manager 233 <a href="postconf.5.html">postconf(5)</a>, configuration parameters 234 235<b>README FILES</b> 236 <a href="BASIC_CONFIGURATION_README.html">BASIC_CONFIGURATION_README</a>, basic configuration 237 <a href="DEBUG_README.html">DEBUG_README</a>, Postfix debugging 238 239<b>LICENSE</b> 240 The Secure Mailer license must be distributed with this software. 241 242<b>AUTHOR(S)</b> 243 Initial version by 244 Magnus Baeck 245 Lund Institute of Technology 246 Sweden 247 248 Wietse Venema 249 IBM T.J. Watson Research 250 P.O. Box 704 251 Yorktown Heights, NY 10598, USA 252 253 Wietse Venema 254 Google, Inc. 255 111 8th Avenue 256 New York, NY 10011, USA 257 258 MASTER(5) 259</pre> </body> </html> 260