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