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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 (host
69                     or service name) or in numeric form (IP address  or  port
70                     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 socket and is acces-
85                     sible 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>fifo</b>   The  service listens on a FIFO (named pipe) and is acces-
95                     sible for local clients only.
96
97                     The service name is a pathname relative  to  the  Postfix
98                     queue    directory    (pathname   controlled   with   the
99                     <b><a href="postconf.5.html#queue_directory">queue_directory</a></b> configuration parameter in <a href="postconf.5.html">main.cf</a>).
100
101              <b>pass</b>   The service listens  on  a  UNIX-domain  socket,  and  is
102                     accessible  to  local  clients only. It receives one open
103                     connection  (file  descriptor  passing)  per   connection
104                     request.
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                     On  Solaris 8 and earlier systems the <b>pass</b> type is imple-
111                     mented with streams sockets.
112
113                     This feature is available as of Postfix version 2.5.
114
115       <b>Private (default: y)</b>
116              Whether or not access is restricted to the mail system.   Inter-
117              net (type <b>inet</b>) services can't be private.
118
119       <b>Unprivileged (default: y)</b>
120              Whether the service runs with root privileges or as the owner of
121              the  Postfix  system  (the  owner  name  is  controlled  by  the
122              <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).
123
124              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
125              privileges.
126
127       <b>Chroot (default: y)</b>
128              Whether or not the service  runs  chrooted  to  the  mail  queue
129              directory (pathname is controlled by the <b><a href="postconf.5.html#queue_directory">queue_directory</a></b> config-
130              uration variable in the <a href="postconf.5.html">main.cf</a> file).
131
132              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>,
133              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
134              chrooted, doing so defeats most of the purpose  of  having  that
135              service in the first place.
136
137              The files in the examples/chroot-setup subdirectory of the Post-
138              fix source archive show set up a Postfix chroot environment on a
139              variety  of  systems.  See  also  <a href="BASIC_CONFIGURATION_README.html">BASIC_CONFIGURATION_README</a> for
140              issues related to running daemons chrooted.
141
142       <b>Wake up time (default: 0)</b>
143              Automatically wake up the named service after the specified num-
144              ber  of seconds. The wake up is implemented by connecting to the
145              service and sending a wake up request.  A ? at the  end  of  the
146              wake-up  time  field  requests  that  no  wake up events be sent
147              before the first time a service is used.  Specify 0 for no auto-
148              matic wake up.
149
150              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
151              timer.
152
153       <b>Process limit (default: $<a href="postconf.5.html#default_process_limit">default_process_limit</a>)</b>
154              The maximum number of processes that may  execute  this  service
155              simultaneously. Specify 0 for no process count limit.
156
157              NOTE:  Some  Postfix  services  must  be configured as a single-
158              process service (for example, <a href="qmgr.8.html"><b>qmgr</b>(8)</a>) and some services must be
159              configured  with  no  process  limit  (for example, <a href="cleanup.8.html"><b>cleanup</b>(8)</a>).
160              These limits must not be changed.
161
162       <b>Command name + arguments</b>
163              The command to be executed.  Characters that are special to  the
164              shell  such  as  "&gt;"  or  "|"  have no special meaning here, and
165              quotes cannot be used to  protect  arguments  containing  white-
166              space.
167
168              The  command  name  is  relative to the Postfix daemon directory
169              (pathname is controlled by  the  <b><a href="postconf.5.html#daemon_directory">daemon_directory</a></b>  configuration
170              variable).
171
172              The  command  argument syntax for specific commands is specified
173              in the respective daemon manual page.
174
175              The following command-line options have the same effect for  all
176              daemon programs:
177
178              <b>-D</b>     Run  the  daemon  under  control by the command specified
179                     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-
180                     uration file.  See <a href="DEBUG_README.html">DEBUG_README</a> for hints and tips.
181
182              <b>-o</b> <i>name</i>=<i>value</i>
183                     Override  the  named <a href="postconf.5.html">main.cf</a> configuration parameter. The
184                     parameter value can refer to other  parameters  as  <i>$name</i>
185                     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.
186
187                     NOTE 1: do not specify whitespace around the  "="  or  in
188                     parameter  values. To specify a parameter value that con-
189                     tains whitespace, use commas instead of spaces, or  spec-
190                     ify the value in <a href="postconf.5.html">main.cf</a>. Example:
191
192                     /etc/postfix/<a href="master.5.html">master.cf</a>:
193                         submission inet .... smtpd
194                             -o smtpd_mumble=$submission_mumble
195
196                     /etc/postfix/<a href="postconf.5.html">main.cf</a>
197                         submission_mumble = text with whitespace...
198
199                     NOTE 2: Over-zealous use of parameter overrides makes the
200                     Postfix configuration hard to  understand  and  maintain.
201                     At  a certain point, it might be easier to configure mul-
202                     tiple instances of Postfix, instead of configuring multi-
203                     ple personalities via <a href="master.5.html">master.cf</a>.
204
205              <b>-v</b>     Increase  the  verbose logging level. Specify multiple <b>-v</b>
206                     options to make a  Postfix  daemon  process  increasingly
207                     verbose.
208
209<b>SEE ALSO</b>
210       <a href="master.8.html">master(8)</a>, process manager
211       <a href="postconf.5.html">postconf(5)</a>, configuration parameters
212
213<b>README FILES</b>
214       <a href="BASIC_CONFIGURATION_README.html">BASIC_CONFIGURATION_README</a>, basic configuration
215       <a href="DEBUG_README.html">DEBUG_README</a>, Postfix debugging
216
217<b>LICENSE</b>
218       The Secure Mailer license must be distributed with this software.
219
220<b>AUTHOR(S)</b>
221       Initial version by
222       Magnus Baeck
223       Lund Institute of Technology
224       Sweden
225
226       Wietse Venema
227       IBM T.J. Watson Research
228       P.O. Box 704
229       Yorktown Heights, NY 10598, USA
230
231                                                                     MASTER(5)
232</pre> </body> </html>
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