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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
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>      Empty lines and whitespace-only lines are  ignored,
38              as  are  lines whose first non-whitespace character
39              is a `#'.
40
41       <b>o</b>      A logical line starts with non-whitespace  text.  A
42              line  that starts with whitespace continues a logi-
43              cal line.
44
45       <b>o</b>      Each logical line defines a single Postfix service.
46              Each  service is identified by its name and type as
47              described below.  When multiple lines  specify  the
48              same  service  name  and type, only the last one is
49              remembered.  Otherwise, the order of <a href="master.5.html">master.cf</a> ser-
50              vice definitions does not matter.
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                     and is accessible to local clients only.  It
114                     receives  one open connection (file descrip-
115                     tor passing) per connection request.
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                     On  Solaris  systems the <b>pass</b> type is imple-
123                     mented with streams sockets.
124
125                     This feature is available as of Postfix ver-
126                     sion 2.5.
127
128       <b>Private (default: y)</b>
129              Whether  or  not  access  is restricted to the mail
130              system.  Internet (type  <b>inet</b>)  services  can't  be
131              private.
132
133       <b>Unprivileged (default: y)</b>
134              Whether the service runs with root privileges or as
135              the owner of the Postfix system (the owner name  is
136              controlled by the <b><a href="postconf.5.html#mail_owner">mail_owner</a></b> configuration variable
137              in the <a href="postconf.5.html">main.cf</a> file).
138
139              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>
140              daemons require privileges.
141
142       <b>Chroot (default: y)</b>
143              Whether  or  not  the  service runs chrooted to the
144              mail queue directory (pathname is controlled by the
145              <b><a href="postconf.5.html#queue_directory">queue_directory</a></b>   configuration   variable  in  the
146              <a href="postconf.5.html">main.cf</a> file).
147
148              Chroot  should  not  be  used  with  the  <a href="local.8.html"><b>local</b>(8)</a>,
149              <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.
150              Although the <a href="proxymap.8.html"><b>proxymap</b>(8)</a> server can  run  chrooted,
151              doing so defeats most of the purpose of having that
152              service in the first place.
153
154              The files in the examples/chroot-setup subdirectory
155              of the Postfix source archive show set up a Postfix
156              chroot environment on a  variety  of  systems.  See
157              also  <a href="BASIC_CONFIGURATION_README.html">BASIC_CONFIGURATION_README</a> for issues related
158              to running daemons chrooted.
159
160       <b>Wake up time (default: 0)</b>
161              Automatically wake up the named service  after  the
162              specified  number of seconds. The wake up is imple-
163              mented by connecting to the service and  sending  a
164              wake  up  request.   A  ? at the end of the wake-up
165              time field requests that no wake up events be  sent
166              before the first time a service is used.  Specify 0
167              for no automatic wake up.
168
169              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
170              a wake up timer.
171
172       <b>Process limit (default: $<a href="postconf.5.html#default_process_limit">default_process_limit</a>)</b>
173              The  maximum  number  of processes that may execute
174              this  service  simultaneously.  Specify  0  for  no
175              process count limit.
176
177              NOTE: Some Postfix services must be configured as a
178              single-process service (for example,  <a href="qmgr.8.html"><b>qmgr</b>(8)</a>)  and
179              some  services  must  be configured with no process
180              limit (for example, <a href="cleanup.8.html"><b>cleanup</b>(8)</a>).  These limits must
181              not be changed.
182
183       <b>Command name + arguments</b>
184              The  command  to  be executed.  Characters that are
185              special to the shell such as "&gt;"  or  "|"  have  no
186              special  meaning here, and quotes cannot be used to
187              protect arguments containing whitespace.
188
189              The command name is relative to the Postfix  daemon
190              directory  (pathname  is  controlled  by  the  <b><a href="postconf.5.html#daemon_directory">dae</a>-</b>
191              <b><a href="postconf.5.html#daemon_directory">mon_directory</a></b> configuration variable).
192
193              The command argument syntax for  specific  commands
194              is  specified in the respective daemon manual page.
195
196              The following command-line options  have  the  same
197              effect for all daemon programs:
198
199              <b>-D</b>     Run  the daemon under control by the command
200                     specified with the <b><a href="postconf.5.html#debugger_command">debugger_command</a></b> variable
201                     in  the  <a href="postconf.5.html">main.cf</a>  configuration  file.   See
202                     <a href="DEBUG_README.html">DEBUG_README</a> for hints and tips.
203
204              <b>-o</b> <i>name</i>=<i>value</i>
205                     Override  the  named  <a href="postconf.5.html">main.cf</a>  configuration
206                     parameter.  The parameter value can refer to
207                     other parameters as <i>$name</i> etc., just like in
208                     <a href="postconf.5.html">main.cf</a>.  See <a href="postconf.5.html"><b>postconf</b>(5)</a> for syntax.
209
210                     NOTE 1: do not specify whitespace around the
211                     "=" or in parameter  values.  To  specify  a
212                     parameter  value  that  contains whitespace,
213                     use commas instead of spaces, or specify the
214                     value in <a href="postconf.5.html">main.cf</a>. Example:
215
216                     /etc/postfix/<a href="master.5.html">master.cf</a>:
217                         submission inet .... smtpd
218                             -o smtpd_mumble=$submission_mumble
219
220                     /etc/postfix/<a href="postconf.5.html">main.cf</a>
221                         submission_mumble = text with whitespace...
222
223                     NOTE  2: Over-zealous use of parameter over-
224                     rides makes the Postfix  configuration  hard
225                     to  understand  and  maintain.  At a certain
226                     point, it might be easier to configure  mul-
227                     tiple  instances of Postfix, instead of con-
228                     figuring  multiple  personalities  via  mas-
229                     ter.cf.
230
231              <b>-v</b>     Increase  the verbose logging level. Specify
232                     multiple <b>-v</b> options to make a Postfix daemon
233                     process increasingly verbose.
234
235<b>SEE ALSO</b>
236       <a href="master.8.html">master(8)</a>, process manager
237       <a href="postconf.5.html">postconf(5)</a>, configuration parameters
238
239<b>README FILES</b>
240       <a href="BASIC_CONFIGURATION_README.html">BASIC_CONFIGURATION_README</a>, basic configuration
241       <a href="DEBUG_README.html">DEBUG_README</a>, Postfix debugging
242
243<b>LICENSE</b>
244       The Secure Mailer license must be  distributed  with  this
245       software.
246
247<b>AUTHOR(S)</b>
248       Initial version by
249       Magnus Baeck
250       Lund Institute of Technology
251       Sweden
252
253       Wietse Venema
254       IBM T.J. Watson Research
255       P.O. Box 704
256       Yorktown Heights, NY 10598, USA
257
258                                                                     MASTER(5)
259</pre> </body> </html>
260