external/ibm-public/postfix/dist/html/transport.5.html

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   7 TRANSPORT(5)                                                      TRANSPORT(5)
   8
   9 <b>NAME</b>
  10        transport - Postfix transport table format
  11
  12 <b>SYNOPSIS</b>
  13        <b>postmap /etc/postfix/transport</b>
  14
  15        <b>postmap -q "</b><i>string</i><b>" /etc/postfix/transport</b>
  16
  17        <b>postmap -q - /etc/postfix/transport</b> &lt;<i>inputfile</i>
  18
  19 <b>DESCRIPTION</b>
  20        The  optional  <a href="transport.5.html"><b>transport</b>(5)</a> table specifies a mapping from
  21        email addresses to message delivery transports  and  next-
  22        hop  destinations.   Message  delivery  transports such as
  23        <b>local</b> or <b>smtp</b> are defined in the <a href="master.5.html"><b>master.cf</b></a> file, and next-
  24        hop  destinations are typically hosts or domain names. The
  25        table is searched by the <a href="trivial-rewrite.8.html"><b>trivial-rewrite</b>(8)</a> daemon.
  26
  27        This  mapping  overrides  the  default   <i>transport</i>:<i>nexthop</i>
  28        selection that is built into Postfix:
  29
  30        <b><a href="postconf.5.html#local_transport">local_transport</a> (default: <a href="local.8.html">local</a>:$<a href="postconf.5.html#myhostname">myhostname</a>)</b>
  31               This  is  the default for final delivery to domains
  32               listed with <b><a href="postconf.5.html#mydestination">mydestination</a></b>, and for [<i>ipaddress</i>] des-
  33               tinations    that    match    <b>$<a href="postconf.5.html#inet_interfaces">inet_interfaces</a></b>   or
  34               <b>$<a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a></b>. The default <i>nexthop</i>  destination
  35               is the MTA hostname.
  36
  37        <b><a href="postconf.5.html#virtual_transport">virtual_transport</a> (default: <a href="virtual.8.html">virtual</a>:)</b>
  38               This  is  the default for final delivery to domains
  39               listed with  <b><a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a></b>.  The  default
  40               <i>nexthop</i> destination is the recipient domain.
  41
  42        <b><a href="postconf.5.html#relay_transport">relay_transport</a> (default: relay:)</b>
  43               This  is the default for remote delivery to domains
  44               listed with <b><a href="postconf.5.html#relay_domains">relay_domains</a></b>. In order  of  decreasing
  45               precedence,  the  <i>nexthop</i> destination is taken from
  46               <b><a href="postconf.5.html#relay_transport">relay_transport</a></b>,   <b><a href="postconf.5.html#sender_dependent_relayhost_maps">sender_dependent_relayhost_maps</a></b>,
  47               <b><a href="postconf.5.html#relayhost">relayhost</a></b>, or from the recipient domain.
  48
  49        <b><a href="postconf.5.html#default_transport">default_transport</a> (default: <a href="smtp.8.html">smtp</a>:)</b>
  50               This  is  the  default for remote delivery to other
  51               destinations.  In order of  decreasing  precedence,
  52               the    <i>nexthop</i>    destination    is    taken   from
  53               <b><a href="postconf.5.html#default_transport">default_transport</a></b>, <b><a href="postconf.5.html#sender_dependent_relayhost_maps">sender_dependent_relayhost_maps</a></b>,
  54               <b><a href="postconf.5.html#relayhost">relayhost</a></b>, or from the recipient domain.
  55
  56        Normally,  the  <a href="transport.5.html"><b>transport</b>(5)</a>  table is specified as a text
  57        file that serves as input to the <a href="postmap.1.html"><b>postmap</b>(1)</a> command.   The
  58        result,  an  indexed file in <b>dbm</b> or <b>db</b> format, is used for
  59        fast searching by the mail  system.  Execute  the  command
  60        "<b>postmap  /etc/postfix/transport</b>"  to  rebuild  an indexed
  61        file after changing the corresponding transport table.
  62
  63        When the table is provided via other means  such  as  NIS,
  64        LDAP  or  SQL,  the  same lookups are done as for ordinary
  65        indexed files.
  66
  67        Alternatively, the table can be  provided  as  a  regular-
  68        expression map where patterns are given as regular expres-
  69        sions, or lookups can be directed to TCP-based server.  In
  70        those  case,  the lookups are done in a slightly different
  71        way as described below under "REGULAR  EXPRESSION  TABLES"
  72        or "TCP-BASED TABLES".
  73
  74 <b>CASE FOLDING</b>
  75        The  search  string is folded to lowercase before database
  76        lookup. As of Postfix 2.3, the search string is  not  case
  77        folded  with database types such as <a href="regexp_table.5.html">regexp</a>: or <a href="pcre_table.5.html">pcre</a>: whose
  78        lookup fields can match both upper and lower case.
  79
  80 <b>TABLE FORMAT</b>
  81        The input format for the <a href="postmap.1.html"><b>postmap</b>(1)</a> command is as follows:
  82
  83        <i>pattern result</i>
  84               When  <i>pattern</i>  matches  the  recipient  address  or
  85               domain, use the corresponding <i>result</i>.
  86
  87        blank lines and comments
  88               Empty lines and whitespace-only lines are  ignored,
  89               as  are  lines whose first non-whitespace character
  90               is a `#'.
  91
  92        multi-line text
  93               A logical line starts with non-whitespace  text.  A
  94               line  that starts with whitespace continues a logi-
  95               cal line.
  96
  97        The <i>pattern</i> specifies an email address, a domain name,  or
  98        a  domain  name  hierarchy, as described in section "TABLE
  99        LOOKUP".
 100
 101        The <i>result</i> is of the form <i>transport:nexthop</i> and  specifies
 102        how or where to deliver mail. This is described in section
 103        "RESULT FORMAT".
 104
 105 <b>TABLE SEARCH ORDER</b>
 106        With lookups from indexed files such as DB or DBM, or from
 107        networked  tables  such  as NIS, LDAP or SQL, patterns are
 108        tried in the order as listed below:
 109
 110        <i>user+extension@domain transport</i>:<i>nexthop</i>
 111               Deliver  mail  for  <i>user+extension@domain</i>   through
 112               <i>transport</i> to <i>nexthop</i>.
 113
 114        <i>user@domain transport</i>:<i>nexthop</i>
 115               Deliver  mail  for <i>user@domain</i> through <i>transport</i> to
 116               <i>nexthop</i>.
 117
 118        <i>domain transport</i>:<i>nexthop</i>
 119               Deliver mail for <i>domain</i> through <i>transport</i>  to  <i>nex-</i>
 120               <i>thop</i>.
 121
 122        <i>.domain transport</i>:<i>nexthop</i>
 123               Deliver  mail  for  any subdomain of <i>domain</i> through
 124               <i>transport</i> to <i>nexthop</i>. This applies  only  when  the
 125               string  <b><a href="postconf.5.html#transport_maps">transport_maps</a></b>  is  not  listed in the <b><a href="postconf.5.html#parent_domain_matches_subdomains">par</a>-</b>
 126               <b><a href="postconf.5.html#parent_domain_matches_subdomains">ent_domain_matches_subdomains</a></b>  configuration   set-
 127               ting.   Otherwise, a domain name matches itself and
 128               its subdomains.
 129
 130        <b>*</b> <i>transport</i>:<i>nexthop</i>
 131               The special pattern <b>*</b> represents any address  (i.e.
 132               it  functions  as  the  wild-card  pattern,  and is
 133               unique to Postfix transport tables).
 134
 135        Note 1:  the  null  recipient  address  is  looked  up  as
 136        <b>$<a href="postconf.5.html#empty_address_recipient">empty_address_recipient</a></b>@<b>$<a href="postconf.5.html#myhostname">myhostname</a></b> (default: mailer-dae-
 137        mon@hostname).
 138
 139        Note 2: <i>user@domain</i>  or  <i>user+extension@domain</i>  lookup  is
 140        available in Postfix 2.0 and later.
 141
 142 <b>RESULT FORMAT</b>
 143        The  lookup  result is of the form <i>transport</i><b>:</b><i>nexthop</i>.  The
 144        <i>transport</i> field specifies a mail delivery  transport  such
 145        as  <b>smtp</b>  or  <b>local</b>. The <i>nexthop</i> field specifies where and
 146        how to deliver mail.
 147
 148        The transport field specifies the name of a mail  delivery
 149        transport (the first name of a mail delivery service entry
 150        in the Postfix <a href="master.5.html"><b>master.cf</b></a> file).
 151
 152        The interpretation  of  the  nexthop  field  is  transport
 153        dependent.  In  the  case  of SMTP, specify a service on a
 154        non-default port as <i>host</i>:<i>service</i>,  and  disable  MX  (mail
 155        exchanger)  DNS lookups with [<i>host</i>] or [<i>host</i>]:<i>port</i>. The []
 156        form is required when you specify an IP address instead of
 157        a hostname.
 158
 159        A  null  <i>transport</i>  and  null <i>nexthop</i> result means "do not
 160        change": use the delivery transport and  nexthop  informa-
 161        tion  that  would  be used when the entire transport table
 162        did not exist.
 163
 164        A non-null <i>transport</i>  field  with  a  null  <i>nexthop</i>  field
 165        resets the nexthop information to the recipient domain.
 166
 167        A  null  <i>transport</i>  field with non-null <i>nexthop</i> field does
 168        not modify the transport information.
 169
 170 <b>EXAMPLES</b>
 171        In order to deliver internal mail directly, while using  a
 172        mail  relay  for  all other mail, specify a null entry for
 173        internal destinations (do not change the  delivery  trans-
 174        port  or  the  nexthop information) and specify a wildcard
 175        for all other destinations.
 176
 177             <b>my.domain    :</b>
 178             <b>.my.domain   :</b>
 179             <b>*            <a href="smtp.8.html">smtp</a>:outbound-relay.my.domain</b>
 180
 181        In order to send mail for <b>example.com</b> and  its  subdomains
 182        via the <b>uucp</b> transport to the UUCP host named <b>example</b>:
 183
 184             <b>example.com      uucp:example</b>
 185             <b>.example.com     uucp:example</b>
 186
 187        When  no  nexthop  host name is specified, the destination
 188        domain name is used instead. For  example,  the  following
 189        directs  mail  for <i>user</i>@<b>example.com</b> via the <b>slow</b> transport
 190        to a mail exchanger for <b>example.com</b>.  The  <b>slow</b>  transport
 191        could be configured to run at most one delivery process at
 192        a time:
 193
 194             <b>example.com      slow:</b>
 195
 196        When no transport is specified, Postfix uses the transport
 197        that  matches  the  address  domain class (see DESCRIPTION
 198        above).  The following sends all mail for <b>example.com</b>  and
 199        its subdomains to host <b>gateway.example.com</b>:
 200
 201             <b>example.com      :[gateway.example.com]</b>
 202             <b>.example.com     :[gateway.example.com]</b>
 203
 204        In  the  above  example, the [] suppress MX lookups.  This
 205        prevents mail routing loops when your machine  is  primary
 206        MX host for <b>example.com</b>.
 207
 208        In  the  case  of delivery via SMTP, one may specify <i>host-</i>
 209        <i>name</i>:<i>service</i> instead of just a host:
 210
 211             <b>example.com      <a href="smtp.8.html">smtp</a>:bar.example:2025</b>
 212
 213        This directs mail for <i>user</i>@<b>example.com</b> to host <b>bar.example</b>
 214        port <b>2025</b>. Instead of a numerical port a symbolic name may
 215        be used. Specify [] around the hostname if MX lookups must
 216        be disabled.
 217
 218        The error mailer can be used to bounce mail:
 219
 220             <b>.example.com     <a href="error.8.html">error</a>:mail for *.example.com is not deliverable</b>
 221
 222        This  causes  all mail for <i>user</i>@<i>anything</i><b>.example.com</b> to be
 223        bounced.
 224
 225 <b>REGULAR EXPRESSION TABLES</b>
 226        This section describes how the table lookups  change  when
 227        the table is given in the form of regular expressions. For
 228        a description of regular expression lookup  table  syntax,
 229        see <a href="regexp_table.5.html"><b>regexp_table</b>(5)</a> or <a href="pcre_table.5.html"><b>pcre_table</b>(5)</a>.
 230
 231        Each  pattern  is  a regular expression that is applied to
 232        the   entire    address    being    looked    up.    Thus,
 233        <i>some.domain.hierarchy</i>  is  not  looked  up  via its parent
 234        domains, nor is <i>user+foo@domain</i> looked up as  <i>user@domain</i>.
 235
 236        Patterns  are applied in the order as specified in the ta-
 237        ble, until a pattern is  found  that  matches  the  search
 238        string.
 239
 240        The <a href="trivial-rewrite.8.html"><b>trivial-rewrite</b>(8)</a> server disallows regular expression
 241        substitution of  $1  etc.  in  regular  expression  lookup
 242        tables,  because  that could open a security hole (Postfix
 243        version 2.3 and later).
 244
 245 <b>TCP-BASED TABLES</b>
 246        This section describes how the table lookups  change  when
 247        lookups are directed to a TCP-based server. For a descrip-
 248        tion of the TCP client/server lookup protocol, see <a href="tcp_table.5.html"><b>tcp_ta-</b></a>
 249        <a href="tcp_table.5.html"><b>ble</b>(5)</a>.  This feature is not available up to and including
 250        Postfix version 2.4.
 251
 252        Each lookup operation uses the  entire  recipient  address
 253        once.   Thus,  <i>some.domain.hierarchy</i>  is not looked up via
 254        its parent domains, nor is <i>user+foo@domain</i>  looked  up  as
 255        <i>user@domain</i>.
 256
 257        Results are the same as with indexed file lookups.
 258
 259 <b>CONFIGURATION PARAMETERS</b>
 260        The  following <a href="postconf.5.html"><b>main.cf</b></a> parameters are especially relevant.
 261        The text below provides  only  a  parameter  summary.  See
 262        <a href="postconf.5.html"><b>postconf</b>(5)</a> for more details including examples.
 263
 264        <b><a href="postconf.5.html#empty_address_recipient">empty_address_recipient</a></b>
 265               The  address  that is looked up instead of the null
 266               sender address.
 267
 268        <b><a href="postconf.5.html#parent_domain_matches_subdomains">parent_domain_matches_subdomains</a></b>
 269               List of Postfix features that use  <i>domain.tld</i>  pat-
 270               terns   to  match  <i>sub.domain.tld</i>  (as  opposed  to
 271               requiring <i>.domain.tld</i> patterns).
 272
 273        <b><a href="postconf.5.html#transport_maps">transport_maps</a></b>
 274               List of transport lookup tables.
 275
 276 <b>SEE ALSO</b>
 277        <a href="trivial-rewrite.8.html">trivial-rewrite(8)</a>, rewrite and resolve addresses
 278        <a href="master.5.html">master(5)</a>, <a href="master.5.html">master.cf</a> file format
 279        <a href="postconf.5.html">postconf(5)</a>, configuration parameters
 280        <a href="postmap.1.html">postmap(1)</a>, Postfix lookup table manager
 281
 282 <b>README FILES</b>
 283        <a href="ADDRESS_REWRITING_README.html">ADDRESS_REWRITING_README</a>, address rewriting guide
 284        <a href="DATABASE_README.html">DATABASE_README</a>, Postfix lookup table overview
 285        <a href="FILTER_README.html">FILTER_README</a>, external content filter
 286
 287 <b>LICENSE</b>
 288        The  Secure  Mailer  license must be distributed with this
 289        software.
 290
 291 <b>AUTHOR(S)</b>
 292        Wietse Venema
 293        IBM T.J. Watson Research
 294        P.O. Box 704
 295        Yorktown Heights, NY 10598, USA
 296
 297                                                                   TRANSPORT(5)
 298 </pre> </body> </html>