Provided by: postfix_2.2.10-1_i386 bug

NAME

       master - Postfix master process configuration file format

DESCRIPTION

       The  Postfix  mail  system  is  implemented by small number of (mostly)
       client commands that are invoked by users, and by a  larger  number  of
       services that run in the background.

       Postfix  services are implemented by daemon processes. These run in the
       background under control  of  the  master(8)  process.   The  master.cf
       configuration  file defines how a client program connects to a service,
       and what daemon program runs when a service is requested.  Most  daemon
       processes  are short-lived and terminate after serving max_use clients,
       or after inactivity for max_idle or more units of time.

       All daemons specified here must speak a Postfix-internal  protocol.  In
       order  to  execute  non-Postfix  software  use the local(8), pipe(8) or
       spawn(8) services, or run the  server  under  control  by  inetd(8)  or
       equivalent.

       After  changing  master.cf  you must execute "postfix reload" to reload
       the configuration.

SYNTAX

       The general format of the master.cf file is as follows:

       ·      Each logical  line  defines  a  single  Postfix  service.   Each
              service  is  identified by its name and type as described below.
              When multiple lines specify the same service name and type, only
              the  last  one is remembered.  Otherwise, the order of master.cf
              service definitions does not matter.

       ·      Empty lines and whitespace-only lines are ignored, as are  lines
              whose first non-whitespace character is a ‘#’.

       ·      A  logical  line  starts  with  non-whitespace text. A line that
              starts with whitespace continues a logical line.

       Each logical line consists of eight  fields  separated  by  whitespace.
       These  are described below in the order as they appear in the master.cf
       file.

       Where applicable a field of "-"  requests  that  the  built-in  default
       value  be  used.  For boolean fields specify "y" or "n" to override the
       default value.

       Service name
              The service name syntax depends on the service type as described
              next.

       Service type
              Specify one of the following service types:

              inet   The  service listens on a TCP/IP socket and is accessible
                     via the network.

                     The service name is specified as host:port, denoting  the
                     host   and  port  on  which  new  connections  should  be
                     accepted. The host  part  (and  colon)  may  be  omitted.
                     Either  host  or port may be given in symbolic form (host
                     or service name) or in numeric form (IP address  or  port
                     number).   Host  information may be enclosed inside "[]",
                     but this form is not necessary.

                     Examples: a  service  named  127.0.0.1:smtp  or  ::1:smtp
                     receives  mail  via  the  loopback  interface only; and a
                     service named 10025 accepts connections on TCP port 10025
                     via  all  interfaces  configured with the inet_interfaces
                     parameter.

                     Note:  with  Postfix  version  2.2  and   later   specify
                     "inet_interfaces  = loopback-only" in main.cf, instead of
                     hard-coding loopback IP address information in  master.cf
                     or in main.cf.

              unix   The  service  listens  on  a  UNIX-domain  socket  and is
                     accessible for local clients only.

                     The service name is a pathname relative  to  the  Postfix
                     queue    directory    (pathname   controlled   with   the
                     queue_directory configuration parameter in main.cf).

                     On Solaris systems the  unix  type  is  implemented  with
                     streams sockets.

              fifo   The  service  listens  on  a  FIFO  (named  pipe)  and is
                     accessible for local clients only.

                     The service name is a pathname relative  to  the  Postfix
                     queue    directory    (pathname   controlled   with   the
                     queue_directory configuration parameter in main.cf).

       Private (default: y)
              Whether  or  not  access  is  restricted  to  the  mail  system.
              Internet (type inet) services can’t be private.

       Unprivileged (default: y)
              Whether the service runs with root privileges or as the owner of
              the  Postfix  system  (the  owner  name  is  controlled  by  the
              mail_owner configuration variable in the main.cf file).

              The  local(8), pipe(8), spawn(8), and virtual(8) daemons require
              privileges.

       Chroot (default: y)
              Whether or not the service  runs  chrooted  to  the  mail  queue
              directory   (pathname   is  controlled  by  the  queue_directory
              configuration variable in the main.cf file).

              Chroot should not be used with the local(8), pipe(8),  spawn(8),
              and virtual(8) daemons.  Although the proxymap(8) server can run
              chrooted, doing so defeats most of the purpose  of  having  that
              service in the first place.

              The  files  in  the  examples/chroot-setup  subdirectory  of the
              Postfix source archive describe how to set up a  Postfix  chroot
              environment     for     your     type     of     machine,    and
              BASIC_CONFIGURATION_README discusses issues related  to  running
              daemons chrooted.

       Wake up time (default: 0)
              Automatically  wake  up  the  named  service after the specified
              number of seconds. The wake up is implemented by  connecting  to
              the  service  and  sending a wake up request.  A ? at the end of
              the wake-up time field requests that wake up events be sent only
              to  services  that  are  actually  being used.  Specify 0 for no
              automatic wake up.

              The pickup(8), qmgr(8) and flush(8) daemons require  a  wake  up
              timer.

       Process limit (default: $default_process_limit)
              The  maximum  number  of processes that may execute this service
              simultaneously. Specify 0 for no process count limit.

              NOTE: Some Postfix services must  be  configured  as  a  single-
              process service (for example, qmgr(8)) and some services must be
              configured with no  process  limit  (for  example,  cleanup(8)).
              These limits must not be changed.

       Command name + arguments
              The  command to be executed.  Characters that are special to the
              shell such as ">" or "|"  have  no  special  meaning  here,  and
              quotes   cannot   be   used   to  protect  arguments  containing
              whitespace.

              The command name is relative to  the  Postfix  daemon  directory
              (pathname  is  controlled  by the daemon_directory configuration
              variable).

              The command argument syntax for specific commands  is  specified
              in the respective daemon manual page.

              The  following command-line options have the same effect for all
              daemon programs:

              -D     Run the daemon under control  by  the  command  specified
                     with   the   debugger_command  variable  in  the  main.cf
                     configuration file.  See DEBUG_README for hints and tips.

              -o name=value
                     Override  the  named main.cf configuration parameter. The
                     parameter value can refer to other  parameters  as  $name
                     etc.,  just like in main.cf.  See postconf(5) for syntax.

                     NOTE 1: do not specify  whitespace  around  the  "=".  In
                     parameter values, either avoid whitespace altogether, use
                     commas instead of spaces, or consider overrides like  "-o
                     name=$override_parameter" with $override_parameter set in
                     main.cf.

                     NOTE 2: Over-zealous use of parameter overrides makes the
                     Postfix  configuration  hard  to understand and maintain.
                     At a certain point,  it  might  be  easier  to  configure
                     multiple  instances  of  Postfix,  instead of configuring
                     multiple personalities via master.cf.

              -v     Increase the verbose logging level. Specify  multiple  -v
                     options  to  make  a  Postfix daemon process increasingly
                     verbose.

SEE ALSO

       master(8), process manager
       postconf(5), configuration parameters

README FILES

       Use "postconf readme_directory" or "postconf html_directory" to  locate
       this information.
       BASIC_CONFIGURATION_README, basic configuration
       DEBUG_README, Postfix debugging

LICENSE

       The Secure Mailer license must be distributed with this software.

AUTHOR(S)

       Initial version by
       Magnus Baeck
       Lund Institute of Technology
       Sweden

       Wietse Venema
       IBM T.J. Watson Research
       P.O. Box 704
       Yorktown Heights, NY 10598, USA

                                                                     MASTER(5)