# TRANSPORT(5)                                         TRANSPORT(5)
# 
# NAME
#        transport - format of Postfix transport table
# 
# SYNOPSIS
#        postmap /etc/postfix/transport
# 
#        postmap -q "string" /etc/postfix/transport
# 
#        postmap -q - /etc/postfix/transport <inputfile
# 
# DESCRIPTION
#        The  optional  transport  table  specifies  a mapping from
#        email addresses  to  message  delivery  transports  and/or
#        relay hosts. The mapping is used by the trivial-rewrite(8)
#        daemon.
# 
#        This mapping overrides the default routing that  is  built
#        into Postfix:
# 
#        mydestination
#               A  list of domains that is by default delivered via
#               $local_transport. This also includes  domains  that
#               match $inet_interfaces or $proxy_interfaces.
# 
#        virtual_mailbox_domains
#               A  list of domains that is by default delivered via
#               $virtual_transport.
# 
#        relay_domains
#               A list of domains that is by default delivered  via
#               $relay_transport.
# 
#        any other destination
#               Mail for any other destination is by default deliv-
#               ered via $default_transport.
# 
#        Normally, the transport table is specified as a text  file
#        that  serves  as  input  to  the  postmap(1) command.  The
#        result, an indexed file in dbm or db format, is  used  for
#        fast  searching  by  the  mail system. Execute the command
#        postmap /etc/postfix/transport in  order  to  rebuild  the
#        indexed file after changing the transport table.
# 
#        When  the  table  is provided via other means such as NIS,
#        LDAP or SQL, the same lookups are  done  as  for  ordinary
#        indexed files.
# 
#        Alternatively,  the  table  can  be provided as a regular-
#        expression map where patterns are given as regular expres-
#        sions,  or lookups can be directed to TCP-based server. In
#        that case, the lookups are done in  a  slightly  different
#        way  as  described below under "REGULAR EXPRESSION TABLES"
#        and "TCP-BASED TABLES".
# 
# TABLE FORMAT
#        The input format for the postmap(1) command is as follows:
# 
#        pattern result
#               When  pattern  matches  the  recipient  address  or
#               domain, use the corresponding result.
# 
#        blank lines and comments
#               Empty lines and whitespace-only lines are  ignored,
#               as  are  lines whose first non-whitespace character
#               is a `#'.
# 
#        multi-line text
#               A logical line starts with non-whitespace  text.  A
#               line  that starts with whitespace continues a logi-
#               cal line.
# 
#        The pattern specifies an email address, a domain name,  or
#        a  domain  name  hierarchy, as described in section "TABLE
#        LOOKUP".
# 
#        The result is of the form transport:nexthop and  specifies
#        how or where to deliver mail. This is described in section
#        "RESULT FORMAT".
# 
# TABLE LOOKUP
#        With lookups from indexed files such as DB or DBM, or from
#        networked  tables  such  as NIS, LDAP or SQL, patterns are
#        tried in the order as listed below:
# 
#        user+extension@domain transport:nexthop
#               Mail for user+extension@domain is delivered through
#               transport to nexthop.
# 
#        user@domain transport:nexthop
#               Mail for user@domain is delivered through transport
#               to nexthop.
# 
#        domain transport:nexthop
#               Mail for domain is delivered through  transport  to
#               nexthop.
# 
#        .domain transport:nexthop
#               Mail  for  any  subdomain  of  domain  is delivered
#               through transport to  nexthop.  This  applies  only
#               when the string transport_maps is not listed in the
#               parent_domain_matches_subdomains configuration set-
#               ting.   Otherwise, a domain name matches itself and
#               its subdomains.
# 
#        Note 1: the special pattern * represents any address (i.e.
#        it functions as the wild-card pattern).
# 
#        Note  2:  the  null  recipient  address  is  looked  up as
#        $empty_address_recipient@$myhostname (default: mailer-dae-
#        mon@hostname).
# 
# RESULT FORMAT
#        The  lookup  result is of the form transport:nexthop.  The
#        transport field specifies a mail delivery  transport  such
#        as  smtp  or  local. The nexthop field specifies where and
#        how to deliver mail.
# 
#        The transport field specifies the name of a mail  delivery
#        transport (the first name of a mail delivery service entry
#        in the Postfix master.cf file).
# 
#        The interpretation  of  the  nexthop  field  is  transport
#        dependent.  In  the  case  of SMTP, specify a service on a
#        non-default port as host:service,  and  disable  MX  (mail
#        exchanger)  DNS lookups with [host] or [host]:port. The []
#        form is required when you specify an IP address instead of
#        a hostname.
# 
#        A  null  transport  and  null nexthop result means "do not
#        change": use the delivery transport and  nexthop  informa-
#        tion  that  would  be used when the entire transport table
#        did not exist.
# 
#        A non-null transport  field  with  a  null  nexthop  field
#        resets the nexthop information to the recipient domain.
# 
#        A  null  transport  field with non-null nexthop field does
#        not modify the transport information.
# 
# EXAMPLES
#        In order to deliver internal mail directly, while using  a
#        mail  relay  for  all other mail, specify a null entry for
#        internal destinations (do not change the  delivery  trans-
#        port  or  the  nexthop information) and specify a wildcard
#        for all other destinations.
# 
#             my.domain    :
#             .my.domain   :
#             *         smtp:outbound-relay.my.domain
# 
#        In order to send mail for example.com and  its  subdomains
#        via the uucp transport to the UUCP host named example:
# 
#             example.com      uucp:example
#             .example.com     uucp:example
# 
#        When  no  nexthop  host name is specified, the destination
#        domain name is used instead. For  example,  the  following
#        directs  mail  for user@example.com via the slow transport
#        to a mail exchanger for example.com.  The  slow  transport
#        could be configured to run at most one delivery process at
#        a time:
# 
#             example.com      slow:
# 
#        When no transport is specified, Postfix uses the transport
#        that  matches  the  address  domain class (see DESCRIPTION
#        above).  The following sends all mail for example.com  and
#        its subdomains to host gateway.example.com:
# 
#             example.com      :[gateway.example.com]
#             .example.com     :[gateway.example.com]
# 
#        In  the  above  example, the [] suppress MX lookups.  This
#        prevents mail routing loops when your machine  is  primary
#        MX host for example.com.
# 
#        In  the  case  of delivery via SMTP, one may specify host-
#        name:service instead of just a host:
# 
#             example.com      smtp:bar.example:2025
# 
#        This directs mail for user@example.com to host bar.example
#        port 2025. Instead of a numerical port a symbolic name may
#        be used. Specify [] around the hostname if MX lookups must
#        be disabled.
# 
#        The error mailer can be used to bounce mail:
# 
#             .example.com      error:mail for *.example.com is not
#        deliverable
# 
#        This causes all mail for user@anything.example.com  to  be
#        bounced.
# 
# REGULAR EXPRESSION TABLES
#        This  section  describes how the table lookups change when
#        the table is given in the form of regular expressions. For
#        a  description  of regular expression lookup table syntax,
#        see regexp_table(5) or pcre_table(5).
# 
#        Each pattern is a regular expression that  is  applied  to
#        the    entire    address    being    looked    up.   Thus,
#        some.domain.hierarchy is not  looked  up  via  its  parent
#        domains,  nor is user+foo@domain looked up as user@domain.
# 
#        Patterns are applied in the  order  as  specified  in  the
#        table,  until  a  pattern is found that matches the search
#        string.
# 
#        Results are the same as with indexed  file  lookups,  with
#        the  additional feature that parenthesized substrings from
#        the pattern can be interpolated as $1, $2 and so on.
# 
# TCP-BASED TABLES
#        This section describes how the table lookups  change  when
#        lookups are directed to a TCP-based server. For a descrip-
#        tion  of  the  TCP  client/server  lookup  protocol,   see
#        tcp_table(5).   This  feature  is not available in Postfix
#        version 2.1.
# 
#        Each lookup operation uses the  entire  recipient  address
#        once.   Thus,  some.domain.hierarchy  is not looked up via
#        its parent domains, nor is user+foo@domain  looked  up  as
#        user@domain.
# 
#        Results are the same as with indexed file lookups.
# 
# CONFIGURATION PARAMETERS
#        The  following main.cf parameters are especially relevant.
#        The text below provides  only  a  parameter  summary.  See
#        postconf(5) for more details including examples.
# 
#        empty_address_recipient
#               The  address  that is looked up instead of the null
#               sender address.
# 
#        parent_domain_matches_subdomains
#               List of Postfix features that use  domain.tld  pat-
#               terns   to  match  sub.domain.tld  (as  opposed  to
#               requiring .domain.tld patterns).
# 
#        transport_maps
#               List of transport lookup tables.
# 
# SEE ALSO
#        trivial-rewrite(8), rewrite and resolve addresses
#        postconf(5), configuration parameters
#        postmap(1), Postfix lookup table manager
# 
# README FILES
#        Use "postconf readme_directory" or  "postconf  html_direc-
#        tory" to locate this information.
#        DATABASE_README, Postfix lookup table overview
#        FILTER_README, external content filter
# 
# 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
# 
#                                                      TRANSPORT(5)
