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