1 <!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" 2 "https://www.w3.org/TR/html4/loose.dtd"> 3 <html> <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 5 <link rel='stylesheet' type='text/css' href='postfix-doc.css'> 6 <title> Postfix manual - master(8) </title> 7 </head> <body> <pre> 8 MASTER(8) MASTER(8) 9 10 <b><a name="name">NAME</a></b> 11 master - Postfix master process 12 13 <b><a name="synopsis">SYNOPSIS</a></b> 14 <b>master</b> [<b>-Dditvw</b>] [<b>-c</b> <i>config</i><b>_</b><i>dir</i>] [<b>-e</b> <i>exit</i><b>_</b><i>time</i>] 15 16 <b><a name="description">DESCRIPTION</a></b> 17 The <a href="master.8.html"><b>master</b>(8)</a> daemon is the resident process that runs Postfix daemons 18 on demand: daemons to send or receive messages via the network, daemons 19 to deliver mail locally, etc. These daemons are created on demand up 20 to a configurable maximum number per service. 21 22 Postfix daemons terminate voluntarily, either after being idle for a 23 configurable amount of time, or after having serviced a configurable 24 number of requests. Exceptions to this rule are the resident queue man- 25 ager, address verification server, and the TLS session cache and 26 pseudo-random number server. 27 28 The behavior of the <a href="master.8.html"><b>master</b>(8)</a> daemon is controlled by the <a href="master.5.html"><b>master.cf</b></a> 29 configuration file, as described in <a href="master.5.html"><b>master</b>(5)</a>. 30 31 Options: 32 33 <b>-c</b> <i>config</i><b>_</b><i>dir</i> 34 Read the <a href="postconf.5.html"><b>main.cf</b></a> and <a href="master.5.html"><b>master.cf</b></a> configuration files in the named 35 directory instead of the default configuration directory. This 36 also overrides the configuration files for other Postfix daemon 37 processes. 38 39 <b>-D</b> After initialization, run a debugger on the master process. The 40 debugging command is specified with the <b><a href="postconf.5.html#debugger_command">debugger_command</a></b> in the 41 <a href="postconf.5.html"><b>main.cf</b></a> global configuration file. 42 43 <b>-d</b> Do not redirect stdin, stdout or stderr to /dev/null, and do not 44 discard the controlling terminal. This must be used for debug- 45 ging only. 46 47 <b>-e</b> <i>exit</i><b>_</b><i>time</i> 48 Terminate the master process after <i>exit</i><b>_</b><i>time</i> seconds. Child pro- 49 cesses terminate at their convenience. 50 51 <b>-i</b> Enable <b>init</b> mode: do not become a session or process group 52 leader; and similar to <b>-s</b>, do not redirect stdout to /dev/null, 53 so that "<a href="postconf.5.html#maillog_file">maillog_file</a> = /dev/stdout" works. This mode is 54 allowed only if the process ID equals 1. 55 56 This feature is available in Postfix 3.3 and later. 57 58 <b>-s</b> Do not redirect stdout to /dev/null, so that "<a href="postconf.5.html#maillog_file">maillog_file</a> = 59 /dev/stdout" works. 60 61 This feature is available in Postfix 3.4 and later. 62 63 <b>-t</b> Test mode. Return a zero exit status when the <b>master.pid</b> lock 64 file does not exist or when that file is not locked. This is 65 evidence that the <a href="master.8.html"><b>master</b>(8)</a> daemon is not running. 66 67 <b>-v</b> Enable verbose logging for debugging purposes. This option is 68 passed on to child processes. Multiple <b>-v</b> options make the soft- 69 ware increasingly verbose. 70 71 <b>-w</b> Wait in a dummy foreground process, while the real master daemon 72 initializes in a background process. The dummy foreground 73 process returns a zero exit status only if the master daemon 74 initialization is successful, and if it completes in a reason- 75 able amount of time. 76 77 This feature is available in Postfix 2.10 and later. 78 79 Signals: 80 81 <b>SIGHUP</b> Upon receipt of a <b>HUP</b> signal (e.g., after "<b>postfix reload</b>"), the 82 master process re-reads its configuration files. If a service 83 has been removed from the <a href="master.5.html"><b>master.cf</b></a> file, its running processes 84 are terminated immediately. Otherwise, running processes are 85 allowed to terminate as soon as is convenient, so that changes 86 in configuration settings affect only new service requests. 87 88 <b>SIGTERM</b> 89 Upon receipt of a <b>TERM</b> signal (e.g., after "<b>postfix abort</b>"), the 90 master process passes the signal on to its child processes and 91 terminates. This is useful for an emergency shutdown. Normally 92 one would terminate only the master ("<b>postfix stop</b>") and allow 93 running processes to finish what they are doing. 94 95 <b><a name="diagnostics">DIAGNOSTICS</a></b> 96 Problems are reported to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>. The exit status is 97 non-zero in case of problems, including problems while initializing as 98 a master daemon process in the background. 99 100 <b><a name="environment">ENVIRONMENT</a></b> 101 <b>MAIL_DEBUG</b> 102 After initialization, start a debugger as specified with the 103 <b><a href="postconf.5.html#debugger_command">debugger_command</a></b> configuration parameter in the <a href="postconf.5.html"><b>main.cf</b></a> configu- 104 ration file. 105 106 <b>MAIL_CONFIG</b> 107 Directory with Postfix configuration files. 108 109 <b><a name="configuration_parameters">CONFIGURATION PARAMETERS</a></b> 110 Unlike most Postfix daemon processes, the <a href="master.8.html"><b>master</b>(8)</a> server does not 111 automatically pick up changes to <a href="postconf.5.html"><b>main.cf</b></a>. Changes to <a href="master.5.html"><b>master.cf</b></a> are 112 never picked up automatically. Use the "<b>postfix reload</b>" command after 113 a configuration change. 114 115 <b><a name="resource_and_rate_controls">RESOURCE AND RATE CONTROLS</a></b> 116 <b><a href="postconf.5.html#default_process_limit">default_process_limit</a> (100)</b> 117 The default maximal number of Postfix child processes that pro- 118 vide a given service. 119 120 <b><a href="postconf.5.html#max_idle">max_idle</a> (100s)</b> 121 The maximum amount of time that an idle Postfix daemon process 122 waits for an incoming connection before terminating voluntarily. 123 124 <b><a href="postconf.5.html#max_use">max_use</a> (100)</b> 125 The maximal number of incoming connections that a Postfix daemon 126 process will service before terminating voluntarily. 127 128 <b><a href="postconf.5.html#service_throttle_time">service_throttle_time</a> (60s)</b> 129 How long the Postfix <a href="master.8.html"><b>master</b>(8)</a> waits before forking a server 130 that appears to be malfunctioning. 131 132 Available in Postfix version 2.6 and later: 133 134 <b><a href="postconf.5.html#master_service_disable">master_service_disable</a> (empty)</b> 135 Selectively disable <a href="master.8.html"><b>master</b>(8)</a> listener ports by service type or 136 by service name and type. 137 138 <b><a name="miscellaneous_controls">MISCELLANEOUS CONTROLS</a></b> 139 <b><a href="postconf.5.html#config_directory">config_directory</a> (see 'postconf -d' output)</b> 140 The default location of the Postfix <a href="postconf.5.html">main.cf</a> and <a href="master.5.html">master.cf</a> con- 141 figuration files. 142 143 <b><a href="postconf.5.html#daemon_directory">daemon_directory</a> (see 'postconf -d' output)</b> 144 The directory with Postfix support programs and daemon programs. 145 146 <b><a href="postconf.5.html#debugger_command">debugger_command</a> (empty)</b> 147 The external command to execute when a Postfix daemon program is 148 invoked with the -D option. 149 150 <b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a> (all)</b> 151 The local network interface addresses that this mail system 152 receives mail on. 153 154 <b><a href="postconf.5.html#inet_protocols">inet_protocols</a> (see 'postconf -d' output)</b> 155 The Internet protocols Postfix will attempt to use when making 156 or accepting connections. 157 158 <b><a href="postconf.5.html#import_environment">import_environment</a> (see 'postconf -d' output)</b> 159 The list of environment variables that a privileged Postfix 160 process will import from a non-Postfix parent process, or 161 name=value environment overrides. 162 163 <b><a href="postconf.5.html#mail_owner">mail_owner</a> (postfix)</b> 164 The UNIX system account that owns the Postfix queue and most 165 Postfix daemon processes. 166 167 <b><a href="postconf.5.html#process_id">process_id</a> (read-only)</b> 168 The process ID of a Postfix command or daemon process. 169 170 <b><a href="postconf.5.html#process_name">process_name</a> (read-only)</b> 171 The process name of a Postfix command or daemon process. 172 173 <b><a href="postconf.5.html#queue_directory">queue_directory</a> (see 'postconf -d' output)</b> 174 The location of the Postfix top-level queue directory. 175 176 <b><a href="postconf.5.html#syslog_facility">syslog_facility</a> (mail)</b> 177 The syslog facility of Postfix logging. 178 179 <b><a href="postconf.5.html#syslog_name">syslog_name</a> (see 'postconf -d' output)</b> 180 A prefix that is prepended to the process name in syslog 181 records, so that, for example, "smtpd" becomes "prefix/smtpd". 182 183 Available in Postfix 3.3 and later: 184 185 <b><a href="postconf.5.html#service_name">service_name</a> (read-only)</b> 186 The <a href="master.5.html">master.cf</a> service name of a Postfix daemon process. 187 188 Available in Postfix 3.6 and later: 189 190 <b><a href="postconf.5.html#known_tcp_ports">known_tcp_ports</a> (lmtp=24, smtp=25, smtps=submissions=465, submis-</b> 191 <b>sion=587)</b> 192 Optional setting that avoids lookups in the <b>services</b>(5) data- 193 base. 194 195 <b><a name="files">FILES</a></b> 196 To expand the directory names below into their actual values, use the 197 command "<b>postconf <a href="postconf.5.html#config_directory">config_directory</a></b>" etc. 198 199 $<a href="postconf.5.html#config_directory">config_directory</a>/<a href="postconf.5.html">main.cf</a>, global configuration file. 200 $<a href="postconf.5.html#config_directory">config_directory</a>/<a href="master.5.html">master.cf</a>, master server configuration file. 201 $<a href="postconf.5.html#queue_directory">queue_directory</a>/pid/master.pid, master lock file. 202 $<a href="postconf.5.html#data_directory">data_directory</a>/master.lock, master lock file. 203 204 <b><a name="see_also">SEE ALSO</a></b> 205 <a href="qmgr.8.html">qmgr(8)</a>, queue manager 206 <a href="verify.8.html">verify(8)</a>, address verification 207 <a href="master.5.html">master(5)</a>, <a href="master.5.html">master.cf</a> configuration file syntax 208 <a href="postconf.5.html">postconf(5)</a>, <a href="postconf.5.html">main.cf</a> configuration file syntax 209 <a href="postlogd.8.html">postlogd(8)</a>, Postfix logging 210 syslogd(8), system logging 211 212 <b><a name="license">LICENSE</a></b> 213 The Secure Mailer license must be distributed with this software. 214 215 <b>AUTHOR(S)</b> 216 Wietse Venema 217 IBM T.J. Watson Research 218 P.O. Box 704 219 Yorktown Heights, NY 10598, USA 220 221 Wietse Venema 222 Google, Inc. 223 111 8th Avenue 224 New York, NY 10011, USA 225 226 MASTER(8) 227 </pre> </body> </html> 228
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