Postfix manual - trivial-rewrite(8)

    TRIVIAL-REWRITE(8)                                          TRIVIAL-REWRITE(8)

    NAME
           trivial-rewrite - Postfix address rewriting and resolving daemon

    SYNOPSIS
           trivial-rewrite [generic Postfix daemon options]

    DESCRIPTION
           The  trivial-rewrite(8)  daemon processes three types of client service
           requests:

           rewrite context address
                  Rewrite an address to standard form, according  to  the  address
                  rewriting context:

                  local  Append  the  domain  names  specified  with  $myorigin or
                         $mydomain to incomplete addresses; do  swap_bangpath  and
                         allow_percent_hack  processing  as  described  below, and
                         strip source routed  addresses  (@site,@site:user@domain)
                         to user@domain form.

                  remote Append  the domain name specified with $remote_header_re-
                         write_domain  to  incomplete  addresses.  Otherwise   the
                         result  is identical to that of the local address rewrit-
                         ing context. This prevents  Postfix  from  appending  the
                         local  domain to spam from poorly written remote clients.

           resolve sender address
                  Resolve the address to a (transport, nexthop, recipient,  flags)
                  quadruple. The meaning of the results is as follows:

                  transport
                         The  delivery agent to use. This is the first field of an
                         entry in the master.cf file.

                  nexthop
                         The host to send to and optional delivery method informa-
                         tion.

                  recipient
                         The  envelope recipient address that is passed on to nex-
                         thop.

                  flags  The address class, whether the address requires relaying,
                         whether the address has problems, and whether the request
                         failed.

           verify sender address
                  Resolve the address for address verification purposes.

    SERVER PROCESS MANAGEMENT
           The trivial-rewrite(8) servers run under control by  the  Postfix  mas-
           ter(8)  server.   Each  server can handle multiple simultaneous connec-
           tions.  When all servers are busy while a client connects,  the  master
           creates  a new server process, provided that the trivial-rewrite server
           process limit is not exceeded.  Each trivial-rewrite server  terminates
           after  serving  at least $max_use clients of after $max_idle seconds of
           idle time.

    STANDARDS
           None. The command does not interact with the outside world.

    SECURITY
           The trivial-rewrite(8) daemon is not security sensitive.   By  default,
           this  daemon  does  not talk to remote or local users.  It can run at a
           fixed low privilege in a chrooted environment.

    DIAGNOSTICS
           Problems and transactions are logged to syslogd(8) or postlogd(8).

    CONFIGURATION PARAMETERS
           On busy mail systems a long time  may  pass  before  a  main.cf  change
           affecting  trivial-rewrite(8)  is  picked  up. Use the command "postfix
           reload" to speed up a change.

           The text below provides only a parameter summary. See  postconf(5)  for
           more details including examples.

    COMPATIBILITY CONTROLS
           resolve_dequoted_address (yes)
                  Resolve  a  recipient  address  safely  instead of correctly, by
                  looking inside quotes.

           Available with Postfix version 2.1 and later:

           resolve_null_domain (no)
                  Resolve an address that ends in the "@" null domain  as  if  the
                  local  hostname were specified, instead of rejecting the address
                  as invalid.

           Available with Postfix version 2.3 and later:

           resolve_numeric_domain (no)
                  Resolve  "user@ipaddress"  as  "user@[ipaddress]",  instead   of
                  rejecting the address as invalid.

           Available with Postfix version 2.5 and later:

           allow_min_user (no)
                  Allow  a  sender  or  recipient address to have `-' as the first
                  character.

    ADDRESS REWRITING CONTROLS
           myorigin ($myhostname)
                  The domain name that locally-posted mail appears to  come  from,
                  and that locally posted mail is delivered to.

           allow_percent_hack (yes)
                  Enable the rewriting of the form "user%domain" to "user@domain".

           append_at_myorigin (yes)
                  With locally submitted mail, append the string  "@$myorigin"  to
                  mail addresses without domain information.

           append_dot_mydomain (Postfix >= 3.0: no, Postfix < 3.0: yes)
                  With  locally  submitted mail, append the string ".$mydomain" to
                  addresses that have no ".domain" information.

           recipient_delimiter (empty)
                  The set of characters that can separate an email address  local-
                  part, user name, or a .forward file name from its extension.

           swap_bangpath (yes)
                  Enable the rewriting of "site!user" into "user@site".

           Available in Postfix 2.2 and later:

           remote_header_rewrite_domain (empty)
                  Rewrite  or  add  message headers in mail from remote clients if
                  the remote_header_rewrite_domain parameter value  is  non-empty,
                  updating  incomplete  addresses with the domain specified in the
                  remote_header_rewrite_domain parameter, and adding missing head-
                  ers.

    ROUTING CONTROLS
           The  following is applicable to Postfix version 2.0 and later.  Earlier
           versions do not have support for:  virtual_transport,  relay_transport,
           virtual_alias_domains, virtual_mailbox_domains or proxy_interfaces.

           local_transport (local:$myhostname)
                  The default mail delivery transport and next-hop destination for
                  final delivery to domains listed  with  mydestination,  and  for
                  [ipaddress]   destinations   that   match   $inet_interfaces  or
                  $proxy_interfaces.

           virtual_transport (virtual)
                  The default mail delivery transport and next-hop destination for
                  final  delivery to domains listed with $virtual_mailbox_domains.

           relay_transport (relay)
                  The default mail delivery transport and next-hop destination for
                  the  relay  domain  address  class: recipient domains that match
                  $relay_domains.

           default_transport (smtp)
                  The default mail delivery transport and next-hop destination for
                  the  default  domain  class: recipient domains that do not match
                  $mydestination,   $inet_interfaces,   $proxy_interfaces,   $vir-
                  tual_alias_domains, $virtual_mailbox_domains, or $relay_domains.

           parent_domain_matches_subdomains (see 'postconf -d' output)
                  A list of Postfix features where the pattern "example.com"  also
                  matches  subdomains  of  example.com,  instead  of  requiring an
                  explicit ".example.com" pattern.

           relayhost (empty)
                  The next-hop destination(s) for non-local mail; takes precedence
                  over non-local domains in recipient addresses.

           transport_maps (empty)
                  Optional  lookup  tables with mappings from recipient address to
                  (message delivery transport, next-hop destination).

           Available in Postfix version 2.3 and later:

           sender_dependent_relayhost_maps (empty)
                  A sender-dependent override for the global  relayhost  parameter
                  setting.

           Available in Postfix version 2.5 and later:

           empty_address_relayhost_maps_lookup_key (<>)
                  The  sender_dependent_relayhost_maps  search string that will be
                  used instead of the null sender address.

           Available in Postfix version 2.7 and later:

           empty_address_default_transport_maps_lookup_key (<>)
                  The sender_dependent_default_transport_maps search  string  that
                  will be used instead of the null sender address.

           sender_dependent_default_transport_maps (empty)
                  A  sender-dependent  override  for  the global default_transport
                  parameter setting.

    ADDRESS VERIFICATION CONTROLS
           Postfix version 2.1 introduces sender and recipient  address  verifica-
           tion.  This feature is implemented by sending probe email messages that
           are not actually delivered.  By default,  address  verification  probes
           use  the  same  route  as regular mail. To override specific aspects of
           message routing for address verification probes, specify one or more of
           the following:

           address_verify_local_transport ($local_transport)
                  Overrides the local_transport parameter setting for address ver-
                  ification probes.

           address_verify_virtual_transport ($virtual_transport)
                  Overrides the virtual_transport parameter  setting  for  address
                  verification probes.

           address_verify_relay_transport ($relay_transport)
                  Overrides the relay_transport parameter setting for address ver-
                  ification probes.

           address_verify_default_transport ($default_transport)
                  Overrides the default_transport parameter  setting  for  address
                  verification probes.

           address_verify_relayhost ($relayhost)
                  Overrides  the relayhost parameter setting for address verifica-
                  tion probes.

           address_verify_transport_maps ($transport_maps)
                  Overrides the transport_maps parameter setting for address veri-
                  fication probes.

           Available in Postfix version 2.3 and later:

           address_verify_sender_dependent_relayhost_maps          ($sender_depen-
           dent_relayhost_maps)
                  Overrides  the sender_dependent_relayhost_maps parameter setting
                  for address verification probes.

           Available in Postfix version 2.7 and later:

           address_verify_sender_dependent_default_transport_maps  ($sender_depen-
           dent_default_transport_maps)
                  Overrides the sender_dependent_default_transport_maps  parameter
                  setting for address verification probes.

    MISCELLANEOUS CONTROLS
           config_directory (see 'postconf -d' output)
                  The  default  location of the Postfix main.cf and master.cf con-
                  figuration files.

           daemon_timeout (18000s)
                  How much time a Postfix daemon process  may  take  to  handle  a
                  request before it is terminated by a built-in watchdog timer.

           empty_address_recipient (MAILER-DAEMON)
                  The recipient of mail addressed to the null address.

           ipc_timeout (3600s)
                  The  time  limit  for  sending  or receiving information over an
                  internal communication channel.

           max_idle (100s)
                  The maximum amount of time that an idle Postfix  daemon  process
                  waits for an incoming connection before terminating voluntarily.

           max_use (100)
                  The maximal number of incoming connections that a Postfix daemon
                  process will service before terminating voluntarily.

           relocated_maps (empty)
                  Optional lookup tables with new contact information for users or
                  domains that no longer exist.

           process_id (read-only)
                  The process ID of a Postfix command or daemon process.

           process_name (read-only)
                  The process name of a Postfix command or daemon process.

           queue_directory (see 'postconf -d' output)
                  The location of the Postfix top-level queue directory.

           show_user_unknown_table_name (yes)
                  Display the name of the recipient table in  the  "User  unknown"
                  responses.

           syslog_facility (mail)
                  The syslog facility of Postfix logging.

           syslog_name (see 'postconf -d' output)
                  A  prefix  that  is  prepended  to  the  process  name in syslog
                  records, so that, for example, "smtpd" becomes "prefix/smtpd".

           Available in Postfix version 2.0 and later:

           helpful_warnings (yes)
                  Log warnings about problematic configuration settings, and  pro-
                  vide helpful suggestions.

           Available in Postfix 3.3 and later:

           service_name (read-only)
                  The master.cf service name of a Postfix daemon process.

    SEE ALSO
           postconf(5), configuration parameters
           transport(5), transport table format
           relocated(5), format of the "user has moved" table
           master(8), process manager
           postlogd(8), Postfix logging
           syslogd(8), system logging

    README FILES
           ADDRESS_CLASS_README, Postfix address classes howto
           ADDRESS_VERIFICATION_README, Postfix address verification

    LICENSE
           The Secure Mailer license must be distributed with this software.

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

           Wietse Venema
           Google, Inc.
           111 8th Avenue
           New York, NY 10011, USA

                                                                TRIVIAL-REWRITE(8)