1 1.1 tron <!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" 2 1.1.1.9 christos "https://www.w3.org/TR/html4/loose.dtd"> 3 1.1 tron <html> <head> 4 1.1.1.7 christos <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 5 1.1.1.8 christos <link rel='stylesheet' type='text/css' href='postfix-doc.css'> 6 1.1 tron <title> Postfix manual - master(8) </title> 7 1.1 tron </head> <body> <pre> 8 1.1 tron MASTER(8) MASTER(8) 9 1.1 tron 10 1.1.1.9 christos <b><a name="name">NAME</a></b> 11 1.1 tron master - Postfix master process 12 1.1 tron 13 1.1.1.9 christos <b><a name="synopsis">SYNOPSIS</a></b> 14 1.1.1.6 christos <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 1.1 tron 16 1.1.1.9 christos <b><a name="description">DESCRIPTION</a></b> 17 1.1.1.4 tron The <a href="master.8.html"><b>master</b>(8)</a> daemon is the resident process that runs Postfix daemons 18 1.1.1.4 tron on demand: daemons to send or receive messages via the network, daemons 19 1.1.1.4 tron to deliver mail locally, etc. These daemons are created on demand up 20 1.1.1.4 tron to a configurable maximum number per service. 21 1.1.1.4 tron 22 1.1.1.4 tron Postfix daemons terminate voluntarily, either after being idle for a 23 1.1.1.4 tron configurable amount of time, or after having serviced a configurable 24 1.1.1.4 tron number of requests. Exceptions to this rule are the resident queue man- 25 1.1.1.4 tron ager, address verification server, and the TLS session cache and 26 1.1.1.4 tron pseudo-random number server. 27 1.1 tron 28 1.1.1.4 tron 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 1.1.1.4 tron configuration file, as described in <a href="master.5.html"><b>master</b>(5)</a>. 30 1.1 tron 31 1.1 tron Options: 32 1.1 tron 33 1.1 tron <b>-c</b> <i>config</i><b>_</b><i>dir</i> 34 1.1.1.4 tron 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 1.1.1.4 tron directory instead of the default configuration directory. This 36 1.1.1.4 tron also overrides the configuration files for other Postfix daemon 37 1.1.1.4 tron processes. 38 1.1.1.4 tron 39 1.1.1.4 tron <b>-D</b> After initialization, run a debugger on the master process. The 40 1.1.1.4 tron debugging command is specified with the <b><a href="postconf.5.html#debugger_command">debugger_command</a></b> in the 41 1.1.1.4 tron <a href="postconf.5.html"><b>main.cf</b></a> global configuration file. 42 1.1.1.4 tron 43 1.1.1.4 tron <b>-d</b> Do not redirect stdin, stdout or stderr to /dev/null, and do not 44 1.1.1.4 tron discard the controlling terminal. This must be used for debug- 45 1.1.1.4 tron ging only. 46 1.1 tron 47 1.1 tron <b>-e</b> <i>exit</i><b>_</b><i>time</i> 48 1.1.1.4 tron Terminate the master process after <i>exit</i><b>_</b><i>time</i> seconds. Child pro- 49 1.1.1.4 tron cesses terminate at their convenience. 50 1.1.1.3 tron 51 1.1.1.6 christos <b>-i</b> Enable <b>init</b> mode: do not become a session or process group 52 1.1.1.6 christos leader; and similar to <b>-s</b>, do not redirect stdout to /dev/null, 53 1.1.1.6 christos so that "<a href="postconf.5.html#maillog_file">maillog_file</a> = /dev/stdout" works. This mode is 54 1.1.1.6 christos allowed only if the process ID equals 1. 55 1.1.1.6 christos 56 1.1.1.6 christos This feature is available in Postfix 3.3 and later. 57 1.1.1.6 christos 58 1.1.1.6 christos <b>-s</b> Do not redirect stdout to /dev/null, so that "<a href="postconf.5.html#maillog_file">maillog_file</a> = 59 1.1.1.6 christos /dev/stdout" works. 60 1.1.1.6 christos 61 1.1.1.6 christos This feature is available in Postfix 3.4 and later. 62 1.1.1.6 christos 63 1.1.1.4 tron <b>-t</b> Test mode. Return a zero exit status when the <b>master.pid</b> lock 64 1.1.1.4 tron file does not exist or when that file is not locked. This is 65 1.1.1.4 tron evidence that the <a href="master.8.html"><b>master</b>(8)</a> daemon is not running. 66 1.1.1.4 tron 67 1.1.1.4 tron <b>-v</b> Enable verbose logging for debugging purposes. This option is 68 1.1.1.4 tron passed on to child processes. Multiple <b>-v</b> options make the soft- 69 1.1.1.4 tron ware increasingly verbose. 70 1.1.1.4 tron 71 1.1.1.4 tron <b>-w</b> Wait in a dummy foreground process, while the real master daemon 72 1.1.1.4 tron initializes in a background process. The dummy foreground 73 1.1.1.4 tron process returns a zero exit status only if the master daemon 74 1.1.1.4 tron initialization is successful, and if it completes in a reason- 75 1.1.1.4 tron able amount of time. 76 1.1.1.4 tron 77 1.1.1.4 tron This feature is available in Postfix 2.10 and later. 78 1.1.1.3 tron 79 1.1 tron Signals: 80 1.1 tron 81 1.1.1.4 tron <b>SIGHUP</b> Upon receipt of a <b>HUP</b> signal (e.g., after "<b>postfix reload</b>"), the 82 1.1.1.4 tron master process re-reads its configuration files. If a service 83 1.1.1.4 tron has been removed from the <a href="master.5.html"><b>master.cf</b></a> file, its running processes 84 1.1.1.4 tron are terminated immediately. Otherwise, running processes are 85 1.1.1.4 tron allowed to terminate as soon as is convenient, so that changes 86 1.1.1.4 tron in configuration settings affect only new service requests. 87 1.1 tron 88 1.1 tron <b>SIGTERM</b> 89 1.1.1.4 tron Upon receipt of a <b>TERM</b> signal (e.g., after "<b>postfix abort</b>"), the 90 1.1.1.4 tron master process passes the signal on to its child processes and 91 1.1.1.4 tron terminates. This is useful for an emergency shutdown. Normally 92 1.1.1.4 tron one would terminate only the master ("<b>postfix stop</b>") and allow 93 1.1 tron running processes to finish what they are doing. 94 1.1 tron 95 1.1.1.9 christos <b><a name="diagnostics">DIAGNOSTICS</a></b> 96 1.1.1.6 christos Problems are reported to <b>syslogd</b>(8) or <a href="postlogd.8.html"><b>postlogd</b>(8)</a>. The exit status is 97 1.1.1.6 christos non-zero in case of problems, including problems while initializing as 98 1.1.1.6 christos a master daemon process in the background. 99 1.1 tron 100 1.1.1.9 christos <b><a name="environment">ENVIRONMENT</a></b> 101 1.1 tron <b>MAIL_DEBUG</b> 102 1.1.1.4 tron After initialization, start a debugger as specified with the 103 1.1.1.4 tron <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 1.1.1.4 tron ration file. 105 1.1 tron 106 1.1 tron <b>MAIL_CONFIG</b> 107 1.1 tron Directory with Postfix configuration files. 108 1.1 tron 109 1.1.1.9 christos <b><a name="configuration_parameters">CONFIGURATION PARAMETERS</a></b> 110 1.1.1.4 tron Unlike most Postfix daemon processes, the <a href="master.8.html"><b>master</b>(8)</a> server does not 111 1.1.1.4 tron 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 1.1.1.4 tron never picked up automatically. Use the "<b>postfix reload</b>" command after 113 1.1.1.4 tron a configuration change. 114 1.1 tron 115 1.1.1.9 christos <b><a name="resource_and_rate_controls">RESOURCE AND RATE CONTROLS</a></b> 116 1.1 tron <b><a href="postconf.5.html#default_process_limit">default_process_limit</a> (100)</b> 117 1.1.1.4 tron The default maximal number of Postfix child processes that pro- 118 1.1.1.4 tron vide a given service. 119 1.1 tron 120 1.1 tron <b><a href="postconf.5.html#max_idle">max_idle</a> (100s)</b> 121 1.1.1.4 tron The maximum amount of time that an idle Postfix daemon process 122 1.1.1.4 tron waits for an incoming connection before terminating voluntarily. 123 1.1 tron 124 1.1 tron <b><a href="postconf.5.html#max_use">max_use</a> (100)</b> 125 1.1.1.4 tron The maximal number of incoming connections that a Postfix daemon 126 1.1.1.4 tron process will service before terminating voluntarily. 127 1.1 tron 128 1.1 tron <b><a href="postconf.5.html#service_throttle_time">service_throttle_time</a> (60s)</b> 129 1.1.1.4 tron How long the Postfix <a href="master.8.html"><b>master</b>(8)</a> waits before forking a server 130 1.1.1.4 tron that appears to be malfunctioning. 131 1.1 tron 132 1.1 tron Available in Postfix version 2.6 and later: 133 1.1 tron 134 1.1 tron <b><a href="postconf.5.html#master_service_disable">master_service_disable</a> (empty)</b> 135 1.1.1.4 tron Selectively disable <a href="master.8.html"><b>master</b>(8)</a> listener ports by service type or 136 1.1.1.4 tron by service name and type. 137 1.1 tron 138 1.1.1.9 christos <b><a name="miscellaneous_controls">MISCELLANEOUS CONTROLS</a></b> 139 1.1 tron <b><a href="postconf.5.html#config_directory">config_directory</a> (see 'postconf -d' output)</b> 140 1.1.1.4 tron 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 1.1.1.4 tron figuration files. 142 1.1 tron 143 1.1 tron <b><a href="postconf.5.html#daemon_directory">daemon_directory</a> (see 'postconf -d' output)</b> 144 1.1.1.4 tron The directory with Postfix support programs and daemon programs. 145 1.1 tron 146 1.1 tron <b><a href="postconf.5.html#debugger_command">debugger_command</a> (empty)</b> 147 1.1.1.4 tron The external command to execute when a Postfix daemon program is 148 1.1.1.4 tron invoked with the -D option. 149 1.1 tron 150 1.1 tron <b><a href="postconf.5.html#inet_interfaces">inet_interfaces</a> (all)</b> 151 1.1.1.9 christos The local network interface addresses that this mail system 152 1.1.1.9 christos receives mail on. 153 1.1 tron 154 1.1.1.9 christos <b><a href="postconf.5.html#inet_protocols">inet_protocols</a> (see 'postconf -d' output)</b> 155 1.1.1.4 tron The Internet protocols Postfix will attempt to use when making 156 1.1.1.4 tron or accepting connections. 157 1.1 tron 158 1.1 tron <b><a href="postconf.5.html#import_environment">import_environment</a> (see 'postconf -d' output)</b> 159 1.1.1.9 christos The list of environment variables that a privileged Postfix 160 1.1.1.6 christos process will import from a non-Postfix parent process, or 161 1.1.1.6 christos name=value environment overrides. 162 1.1 tron 163 1.1 tron <b><a href="postconf.5.html#mail_owner">mail_owner</a> (postfix)</b> 164 1.1.1.6 christos The UNIX system account that owns the Postfix queue and most 165 1.1.1.4 tron Postfix daemon processes. 166 1.1 tron 167 1.1 tron <b><a href="postconf.5.html#process_id">process_id</a> (read-only)</b> 168 1.1.1.4 tron The process ID of a Postfix command or daemon process. 169 1.1 tron 170 1.1 tron <b><a href="postconf.5.html#process_name">process_name</a> (read-only)</b> 171 1.1.1.4 tron The process name of a Postfix command or daemon process. 172 1.1 tron 173 1.1 tron <b><a href="postconf.5.html#queue_directory">queue_directory</a> (see 'postconf -d' output)</b> 174 1.1.1.4 tron The location of the Postfix top-level queue directory. 175 1.1 tron 176 1.1 tron <b><a href="postconf.5.html#syslog_facility">syslog_facility</a> (mail)</b> 177 1.1 tron The syslog facility of Postfix logging. 178 1.1 tron 179 1.1 tron <b><a href="postconf.5.html#syslog_name">syslog_name</a> (see 'postconf -d' output)</b> 180 1.1.1.6 christos A prefix that is prepended to the process name in syslog 181 1.1.1.6 christos records, so that, for example, "smtpd" becomes "prefix/smtpd". 182 1.1.1.6 christos 183 1.1.1.6 christos Available in Postfix 3.3 and later: 184 1.1.1.6 christos 185 1.1.1.6 christos <b><a href="postconf.5.html#service_name">service_name</a> (read-only)</b> 186 1.1.1.6 christos The <a href="master.5.html">master.cf</a> service name of a Postfix daemon process. 187 1.1 tron 188 1.1.1.7 christos Available in Postfix 3.6 and later: 189 1.1.1.7 christos 190 1.1.1.7 christos <b><a href="postconf.5.html#known_tcp_ports">known_tcp_ports</a> (lmtp=24, smtp=25, smtps=submissions=465, submis-</b> 191 1.1.1.7 christos <b>sion=587)</b> 192 1.1.1.7 christos Optional setting that avoids lookups in the <b>services</b>(5) data- 193 1.1.1.7 christos base. 194 1.1.1.7 christos 195 1.1.1.9 christos <b><a name="files">FILES</a></b> 196 1.1.1.7 christos To expand the directory names below into their actual values, use the 197 1.1.1.4 tron command "<b>postconf <a href="postconf.5.html#config_directory">config_directory</a></b>" etc. 198 1.1 tron 199 1.1 tron $<a href="postconf.5.html#config_directory">config_directory</a>/<a href="postconf.5.html">main.cf</a>, global configuration file. 200 1.1 tron $<a href="postconf.5.html#config_directory">config_directory</a>/<a href="master.5.html">master.cf</a>, master server configuration file. 201 1.1 tron $<a href="postconf.5.html#queue_directory">queue_directory</a>/pid/master.pid, master lock file. 202 1.1 tron $<a href="postconf.5.html#data_directory">data_directory</a>/master.lock, master lock file. 203 1.1 tron 204 1.1.1.9 christos <b><a name="see_also">SEE ALSO</a></b> 205 1.1 tron <a href="qmgr.8.html">qmgr(8)</a>, queue manager 206 1.1 tron <a href="verify.8.html">verify(8)</a>, address verification 207 1.1 tron <a href="master.5.html">master(5)</a>, <a href="master.5.html">master.cf</a> configuration file syntax 208 1.1.1.2 tron <a href="postconf.5.html">postconf(5)</a>, <a href="postconf.5.html">main.cf</a> configuration file syntax 209 1.1.1.6 christos <a href="postlogd.8.html">postlogd(8)</a>, Postfix logging 210 1.1 tron syslogd(8), system logging 211 1.1 tron 212 1.1.1.9 christos <b><a name="license">LICENSE</a></b> 213 1.1.1.4 tron The Secure Mailer license must be distributed with this software. 214 1.1 tron 215 1.1 tron <b>AUTHOR(S)</b> 216 1.1 tron Wietse Venema 217 1.1 tron IBM T.J. Watson Research 218 1.1 tron P.O. Box 704 219 1.1 tron Yorktown Heights, NY 10598, USA 220 1.1 tron 221 1.1.1.5 christos Wietse Venema 222 1.1.1.5 christos Google, Inc. 223 1.1.1.5 christos 111 8th Avenue 224 1.1.1.5 christos New York, NY 10011, USA 225 1.1.1.5 christos 226 1.1 tron MASTER(8) 227 1.1 tron </pre> </body> </html> 228
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