transport.5.html revision 1.1.1.6
1 <!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" 2 "http://www.w3.org/TR/html4/loose.dtd"> 3 <html> <head> 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 5 <title> Postfix manual - transport(5) </title> 6 </head> <body> <pre> 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> <<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 email 21 addresses to message delivery transports and next-hop destinations. 22 Message delivery transports such as <b>local</b> or <b>smtp</b> are defined in the 23 <a href="master.5.html"><b>master.cf</b></a> file, and next-hop destinations are typically hosts or domain 24 names. The table is searched by the <a href="trivial-rewrite.8.html"><b>trivial-rewrite</b>(8)</a> daemon. 25 26 This mapping overrides the default <i>transport</i>:<i>nexthop</i> selection that is 27 built into Postfix: 28 29 <b><a href="postconf.5.html#local_transport">local_transport</a> (default: <a href="local.8.html">local</a>:$<a href="postconf.5.html#myhostname">myhostname</a>)</b> 30 This is the default for final delivery to domains listed with 31 <b><a href="postconf.5.html#mydestination">mydestination</a></b>, and for [<i>ipaddress</i>] destinations that match 32 <b>$<a href="postconf.5.html#inet_interfaces">inet_interfaces</a></b> or <b>$<a href="postconf.5.html#proxy_interfaces">proxy_interfaces</a></b>. The default <i>nexthop</i> des- 33 tination is the MTA hostname. 34 35 <b><a href="postconf.5.html#virtual_transport">virtual_transport</a> (default: <a href="virtual.8.html">virtual</a>:)</b> 36 This is the default for final delivery to domains listed with 37 <b><a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a></b>. The default <i>nexthop</i> destination is the 38 recipient domain. 39 40 <b><a href="postconf.5.html#relay_transport">relay_transport</a> (default: relay:)</b> 41 This is the default for remote delivery to domains listed with 42 <b><a href="postconf.5.html#relay_domains">relay_domains</a></b>. In order of decreasing precedence, the <i>nexthop</i> 43 destination is taken from <b><a href="postconf.5.html#relay_transport">relay_transport</a></b>, <b><a href="postconf.5.html#sender_dependent_relayhost_maps">sender_depen</a>-</b> 44 <b><a href="postconf.5.html#sender_dependent_relayhost_maps">dent_relayhost_maps</a></b>, <b><a href="postconf.5.html#relayhost">relayhost</a></b>, or from the recipient domain. 45 46 <b><a href="postconf.5.html#default_transport">default_transport</a> (default: <a href="smtp.8.html">smtp</a>:)</b> 47 This is the default for remote delivery to other destinations. 48 In order of decreasing precedence, the <i>nexthop</i> destination is 49 taken from <b><a href="postconf.5.html#sender_dependent_default_transport_maps">sender_dependent_default_transport_maps</a>,</b> 50 <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>, <b><a href="postconf.5.html#relayhost">relayhost</a></b>, 51 or from the recipient domain. 52 53 Normally, the <a href="transport.5.html"><b>transport</b>(5)</a> table is specified as a text file that 54 serves as input to the <a href="postmap.1.html"><b>postmap</b>(1)</a> command. The result, an indexed file 55 in <b>dbm</b> or <b>db</b> format, is used for fast searching by the mail system. 56 Execute the command "<b>postmap /etc/postfix/transport</b>" to rebuild an 57 indexed file after changing the corresponding transport table. 58 59 When the table is provided via other means such as NIS, LDAP or SQL, 60 the same lookups are done as for ordinary indexed files. 61 62 Alternatively, the table can be provided as a regular-expression map 63 where patterns are given as regular expressions, or lookups can be 64 directed to a TCP-based server. In those case, the lookups are done in 65 a slightly different way as described below under "REGULAR EXPRESSION 66 TABLES" or "TCP-BASED TABLES". 67 68 <b>CASE FOLDING</b> 69 The search string is folded to lowercase before database lookup. As of 70 Postfix 2.3, the search string is not case folded with database types 71 such as <a href="regexp_table.5.html">regexp</a>: or <a href="pcre_table.5.html">pcre</a>: whose lookup fields can match both upper and 72 lower case. 73 74 <b>TABLE FORMAT</b> 75 The input format for the <a href="postmap.1.html"><b>postmap</b>(1)</a> command is as follows: 76 77 <i>pattern result</i> 78 When <i>pattern</i> matches the recipient address or domain, use the 79 corresponding <i>result</i>. 80 81 blank lines and comments 82 Empty lines and whitespace-only lines are ignored, as are lines 83 whose first non-whitespace character is a `#'. 84 85 multi-line text 86 A logical line starts with non-whitespace text. A line that 87 starts with whitespace continues a logical line. 88 89 The <i>pattern</i> specifies an email address, a domain name, or a domain name 90 hierarchy, as described in section "TABLE SEARCH ORDER". 91 92 The <i>result</i> is of the form <i>transport:nexthop</i> and specifies how or where 93 to deliver mail. This is described in section "RESULT FORMAT". 94 95 <b>TABLE SEARCH ORDER</b> 96 With lookups from indexed files such as DB or DBM, or from networked 97 tables such as NIS, LDAP or SQL, patterns are tried in the order as 98 listed below: 99 100 <i>user+extension@domain transport</i>:<i>nexthop</i> 101 Deliver mail for <i>user+extension@domain</i> through <i>transport</i> to <i>nex-</i> 102 <i>thop</i>. 103 104 <i>user@domain transport</i>:<i>nexthop</i> 105 Deliver mail for <i>user@domain</i> through <i>transport</i> to <i>nexthop</i>. 106 107 <i>domain transport</i>:<i>nexthop</i> 108 Deliver mail for <i>domain</i> through <i>transport</i> to <i>nexthop</i>. 109 110 <i>.domain transport</i>:<i>nexthop</i> 111 Deliver mail for any subdomain of <i>domain</i> through <i>transport</i> to 112 <i>nexthop</i>. This applies only when the string <b><a href="postconf.5.html#transport_maps">transport_maps</a></b> is not 113 listed in the <b><a href="postconf.5.html#parent_domain_matches_subdomains">parent_domain_matches_subdomains</a></b> configuration 114 setting. Otherwise, a domain name matches itself and its subdo- 115 mains. 116 117 <b>*</b> <i>transport</i>:<i>nexthop</i> 118 The special pattern <b>*</b> represents any address (i.e. it functions 119 as the wild-card pattern, and is unique to Postfix transport 120 tables). 121 122 Note 1: the null recipient address is looked up as 123 <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-daemon@hostname). 124 125 Note 2: <i>user@domain</i> or <i>user+extension@domain</i> lookup is available in 126 Postfix 2.0 and later. 127 128 <b>RESULT FORMAT</b> 129 The lookup result is of the form <i>transport</i><b>:</b><i>nexthop</i>. The <i>transport</i> 130 field specifies a mail delivery transport such as <b>smtp</b> or <b>local</b>. The 131 <i>nexthop</i> field specifies where and how to deliver mail. 132 133 The transport field specifies the name of a mail delivery transport 134 (the first name of a mail delivery service entry in the Postfix <a href="master.5.html"><b>mas-</b> 135 <b>ter.cf</b></a> file). 136 137 The nexthop field usually specifies one recipient domain or hostname. 138 In the case of the Postfix SMTP/LMTP client, the nexthop field may con- 139 tain a list of nexthop destinations separated by comma or whitespace 140 (Postfix 3.5 and later). 141 142 The syntax of a nexthop destination is transport dependent. With SMTP, 143 specify a service on a non-default port as <i>host</i>:<i>service</i>, and disable MX 144 (mail exchanger) DNS lookups with [<i>host</i>] or [<i>host</i>]:<i>port</i>. The [] form is 145 required when you specify an IP address instead of a hostname. 146 147 A null <i>transport</i> and null <i>nexthop</i> field means "do not change": use the 148 delivery transport and nexthop information that would be used when the 149 entire transport table did not exist. 150 151 A non-null <i>transport</i> field with a null <i>nexthop</i> field resets the nexthop 152 information to the recipient domain. 153 154 A null <i>transport</i> field with non-null <i>nexthop</i> field does not modify the 155 transport information. 156 157 <b>EXAMPLES</b> 158 In order to deliver internal mail directly, while using a mail relay 159 for all other mail, specify a null entry for internal destinations (do 160 not change the delivery transport or the nexthop information) and spec- 161 ify a wildcard for all other destinations. 162 163 <b>my.domain :</b> 164 <b>.my.domain :</b> 165 <b>* <a href="smtp.8.html">smtp</a>:outbound-relay.my.domain</b> 166 167 In order to send mail for <b>example.com</b> and its subdomains via the <b>uucp</b> 168 transport to the UUCP host named <b>example</b>: 169 170 <b>example.com uucp:example</b> 171 <b>.example.com uucp:example</b> 172 173 When no nexthop host name is specified, the destination domain name is 174 used instead. For example, the following directs mail for <i>user</i>@<b>exam-</b> 175 <b>ple.com</b> via the <b>slow</b> transport to a mail exchanger for <b>example.com</b>. 176 The <b>slow</b> transport could be configured to run at most one delivery 177 process at a time: 178 179 <b>example.com slow:</b> 180 181 When no transport is specified, Postfix uses the transport that matches 182 the address domain class (see DESCRIPTION above). The following sends 183 all mail for <b>example.com</b> and its subdomains to host <b>gateway.exam-</b> 184 <b>ple.com</b>: 185 186 <b>example.com :[gateway.example.com]</b> 187 <b>.example.com :[gateway.example.com]</b> 188 189 In the above example, the [] suppress MX lookups. This prevents mail 190 routing loops when your machine is primary MX host for <b>example.com</b>. 191 192 In the case of delivery via SMTP or LMTP, one may specify <i>host</i>:<i>service</i> 193 instead of just a host: 194 195 <b>example.com <a href="smtp.8.html">smtp</a>:bar.example:2025</b> 196 197 This directs mail for <i>user</i>@<b>example.com</b> to host <b>bar.example</b> port <b>2025</b>. 198 Instead of a numerical port a symbolic name may be used. Specify [] 199 around the hostname if MX lookups must be disabled. 200 201 Deliveries via SMTP or LMTP support multiple destinations (Postfix >= 202 3.5): 203 204 <b>example.com <a href="smtp.8.html">smtp</a>:bar.example, foo.example</b> 205 206 This tries to deliver to <b>bar.example</b> before trying to deliver to 207 <b>foo.example</b>. 208 209 The error mailer can be used to bounce mail: 210 211 <b>.example.com <a href="error.8.html">error</a>:mail for *.example.com is not deliverable</b> 212 213 This causes all mail for <i>user</i>@<i>anything</i><b>.example.com</b> to be bounced. 214 215 <b>REGULAR EXPRESSION TABLES</b> 216 This section describes how the table lookups change when the table is 217 given in the form of regular expressions. For a description of regular 218 expression lookup table syntax, 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>. 219 220 Each pattern is a regular expression that is applied to the entire 221 address being looked up. Thus, <i>some.domain.hierarchy</i> is not looked up 222 via its parent domains, nor is <i>user+foo@domain</i> looked up as 223 <i>user@domain</i>. 224 225 Patterns are applied in the order as specified in the table, until a 226 pattern is found that matches the search string. 227 228 The <a href="trivial-rewrite.8.html"><b>trivial-rewrite</b>(8)</a> server disallows regular expression substitution 229 of $1 etc. in regular expression lookup tables, because that could open 230 a security hole (Postfix version 2.3 and later). 231 232 <b>TCP-BASED TABLES</b> 233 This section describes how the table lookups change when lookups are 234 directed to a TCP-based server. For a description of the TCP 235 client/server lookup protocol, see <a href="tcp_table.5.html"><b>tcp_table</b>(5)</a>. This feature is not 236 available up to and including Postfix version 2.4. 237 238 Each lookup operation uses the entire recipient address once. Thus, 239 <i>some.domain.hierarchy</i> is not looked up via its parent domains, nor is 240 <i>user+foo@domain</i> looked up as <i>user@domain</i>. 241 242 Results are the same as with indexed file lookups. 243 244 <b>CONFIGURATION PARAMETERS</b> 245 The following <a href="postconf.5.html"><b>main.cf</b></a> parameters are especially relevant. The text 246 below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for more 247 details including examples. 248 249 <b><a href="postconf.5.html#empty_address_recipient">empty_address_recipient</a> (MAILER-DAEMON)</b> 250 The recipient of mail addressed to the null address. 251 252 <b><a href="postconf.5.html#parent_domain_matches_subdomains">parent_domain_matches_subdomains</a> (see 'postconf -d' output)</b> 253 A list of Postfix features where the pattern "example.com" also 254 matches subdomains of example.com, instead of requiring an 255 explicit ".example.com" pattern. 256 257 <b><a href="postconf.5.html#transport_maps">transport_maps</a> (empty)</b> 258 Optional lookup tables with mappings from recipient address to 259 (message delivery transport, next-hop destination). 260 261 <b>SEE ALSO</b> 262 <a href="trivial-rewrite.8.html">trivial-rewrite(8)</a>, rewrite and resolve addresses 263 <a href="master.5.html">master(5)</a>, <a href="master.5.html">master.cf</a> file format 264 <a href="postconf.5.html">postconf(5)</a>, configuration parameters 265 <a href="postmap.1.html">postmap(1)</a>, Postfix lookup table manager 266 267 <b>README FILES</b> 268 <a href="ADDRESS_REWRITING_README.html">ADDRESS_REWRITING_README</a>, address rewriting guide 269 <a href="DATABASE_README.html">DATABASE_README</a>, Postfix lookup table overview 270 <a href="FILTER_README.html">FILTER_README</a>, external content filter 271 272 <b>LICENSE</b> 273 The Secure Mailer license must be distributed with this software. 274 275 <b>AUTHOR(S)</b> 276 Wietse Venema 277 IBM T.J. Watson Research 278 P.O. Box 704 279 Yorktown Heights, NY 10598, USA 280 281 Wietse Venema 282 Google, Inc. 283 111 8th Avenue 284 New York, NY 10011, USA 285 286 TRANSPORT(5) 287 </pre> </body> </html> 288
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