TRANSPORT(5)                                         TRANSPORT(5)


NAME
       transport - format of Postfix transport table

SYNOPSIS
       postmap /etc/postfix/transport

DESCRIPTION
       The  optional  transport  file  specifies  a  mapping from
       domain hierarchies to message delivery  transports  and/or
       relay hosts. The mapping is used by the trivial-rewrite(8)
       daemon.

       The file 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.  After  updating  this
       table, issue the postfix reload command to make the change
       visible.

       The format of the transport table is as follows:

       blanks and comments
              Blank lines are ignored,  as  are  lines  beginning
              with `#'.

       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.

       Note:  transport  map entries take precedence over domains
       specified in the mydestination parameter. If you  use  the
       optional  transport  map,  it  may  be  safer  to  specify
       explicit entries for all domains specified  in  mydestina-
       tion, for example:

            hostname.my.domain       local:
            localhost.my.domain      local:

       The  interpretation  of  the  nexthop  field  is transport
       dependent. In the case of SMTP, specify host:service for a
       non-default  server port, and use [host] or [host:port] in
       order to disable MX (mail exchanger) DNS lookups.  The  []
       form  can  also be used with IP addresses instead of host-
       names.

EXAMPLES
       In order to send mail for foo.org and its subdomains
       via the uucp transport to the UUCP host named foo:

            foo.org      uucp:foo
            .foo.org     uucp:foo



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TRANSPORT(5)                                         TRANSPORT(5)


       When no nexthop host name is specified, the destination domain
       name is used instead. For example, the following directs mail for
       user@foo.org via the slow transport to a mail
       exchanger for foo.org.  The slow transport could be
       something that runs at most one delivery process at a time:

            foo.org      slow:

       When no transport is specified, the default transport is
       used, as specified via the default_transport configuration
       parameter. The following sends all mail for foo.org and its
       subdomains to host gateway.foo.org:

            foo.org      :[gateway.foo.org]
            .foo.org     :[gateway.foo.org]

       In the above example, the [] are used to suppress MX lookups.
       The result would likely point to your local machine.

       In the case of delivery via SMTP, one may specify
       hostname:service instead of just a host:

            foo.org      smtp:bar.org:2025

       This directs mail for user@foo.org to host bar.org
       port 2025. Instead of a numerical port a symbolic name may be
       used. Specify [] around the destination in order to disable MX lookups.

       The error mailer can be used to bounce mail:

            .foo.org      error:mail for *.foo.org is not deliverable

       This causes all mail for user@anythingfoo.org
       to be bounced.

CONFIGURATION PARAMETERS
       The following main.cf parameters are  especially  relevant
       to  this  topic.  See  the Postfix main.cf file for syntax
       details and for default values.  Use  the  postfix  reload
       command after a configuration change.

       transport_maps
              List of transport lookup tables.

       Other parameters of interest:

       default_transport
              The  transport  to use when no transport is explic-
              itly specified.

       relayhost
              The default host to send to when no transport table
              entry matches.




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TRANSPORT(5)                                         TRANSPORT(5)


SEE ALSO
       postmap(1) create mapping table
       trivial-rewrite(8) rewrite and resolve addresses

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












































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