transport.5.html revision 1.1.1.8
1 1.1 tron <!doctype html public "-//W3C//DTD HTML 4.01 Transitional//EN" 2 1.1.1.8 christos "https://www.w3.org/TR/html4/loose.dtd"> 3 1.1 tron <html> <head> 4 1.1.1.6 christos <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 5 1.1.1.7 christos <link rel='stylesheet' type='text/css' href='postfix-doc.css'> 6 1.1 tron <title> Postfix manual - transport(5) </title> 7 1.1 tron </head> <body> <pre> 8 1.1 tron TRANSPORT(5) TRANSPORT(5) 9 1.1 tron 10 1.1.1.8 christos <b><a name="name">NAME</a></b> 11 1.1 tron transport - Postfix transport table format 12 1.1 tron 13 1.1.1.8 christos <b><a name="synopsis">SYNOPSIS</a></b> 14 1.1 tron <b>postmap /etc/postfix/transport</b> 15 1.1 tron 16 1.1 tron <b>postmap -q "</b><i>string</i><b>" /etc/postfix/transport</b> 17 1.1 tron 18 1.1 tron <b>postmap -q - /etc/postfix/transport</b> <<i>inputfile</i> 19 1.1 tron 20 1.1.1.8 christos <b><a name="description">DESCRIPTION</a></b> 21 1.1.1.3 tron The optional <a href="transport.5.html"><b>transport</b>(5)</a> table specifies a mapping from email 22 1.1.1.3 tron addresses to message delivery transports and next-hop destinations. 23 1.1.1.3 tron Message delivery transports such as <b>local</b> or <b>smtp</b> are defined in the 24 1.1.1.3 tron <a href="master.5.html"><b>master.cf</b></a> file, and next-hop destinations are typically hosts or domain 25 1.1.1.3 tron names. The table is searched by the <a href="trivial-rewrite.8.html"><b>trivial-rewrite</b>(8)</a> daemon. 26 1.1 tron 27 1.1.1.3 tron This mapping overrides the default <i>transport</i>:<i>nexthop</i> selection that is 28 1.1.1.3 tron built into Postfix: 29 1.1 tron 30 1.1 tron <b><a href="postconf.5.html#local_transport">local_transport</a> (default: <a href="local.8.html">local</a>:$<a href="postconf.5.html#myhostname">myhostname</a>)</b> 31 1.1.1.3 tron This is the default for final delivery to domains listed with 32 1.1.1.3 tron <b><a href="postconf.5.html#mydestination">mydestination</a></b>, and for [<i>ipaddress</i>] destinations that match 33 1.1.1.3 tron <b>$<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- 34 1.1.1.3 tron tination is the MTA hostname. 35 1.1 tron 36 1.1 tron <b><a href="postconf.5.html#virtual_transport">virtual_transport</a> (default: <a href="virtual.8.html">virtual</a>:)</b> 37 1.1.1.3 tron This is the default for final delivery to domains listed with 38 1.1.1.3 tron <b><a href="postconf.5.html#virtual_mailbox_domains">virtual_mailbox_domains</a></b>. The default <i>nexthop</i> destination is the 39 1.1.1.3 tron recipient domain. 40 1.1 tron 41 1.1 tron <b><a href="postconf.5.html#relay_transport">relay_transport</a> (default: relay:)</b> 42 1.1.1.3 tron This is the default for remote delivery to domains listed with 43 1.1.1.3 tron <b><a href="postconf.5.html#relay_domains">relay_domains</a></b>. In order of decreasing precedence, the <i>nexthop</i> 44 1.1.1.3 tron 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> 45 1.1.1.3 tron <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. 46 1.1 tron 47 1.1 tron <b><a href="postconf.5.html#default_transport">default_transport</a> (default: <a href="smtp.8.html">smtp</a>:)</b> 48 1.1.1.3 tron This is the default for remote delivery to other destinations. 49 1.1.1.3 tron In order of decreasing precedence, the <i>nexthop</i> destination is 50 1.1.1.3 tron taken from <b><a href="postconf.5.html#sender_dependent_default_transport_maps">sender_dependent_default_transport_maps</a>,</b> 51 1.1.1.3 tron <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>, 52 1.1.1.3 tron or from the recipient domain. 53 1.1.1.3 tron 54 1.1.1.3 tron Normally, the <a href="transport.5.html"><b>transport</b>(5)</a> table is specified as a text file that 55 1.1.1.3 tron serves as input to the <a href="postmap.1.html"><b>postmap</b>(1)</a> command. The result, an indexed file 56 1.1.1.3 tron in <b>dbm</b> or <b>db</b> format, is used for fast searching by the mail system. 57 1.1.1.3 tron Execute the command "<b>postmap /etc/postfix/transport</b>" to rebuild an 58 1.1.1.3 tron indexed file after changing the corresponding transport table. 59 1.1.1.3 tron 60 1.1.1.3 tron When the table is provided via other means such as NIS, LDAP or SQL, 61 1.1.1.3 tron the same lookups are done as for ordinary indexed files. 62 1.1.1.3 tron 63 1.1.1.3 tron Alternatively, the table can be provided as a regular-expression map 64 1.1.1.3 tron where patterns are given as regular expressions, or lookups can be 65 1.1.1.6 christos directed to a TCP-based server. In those case, the lookups are done in 66 1.1.1.6 christos a slightly different way as described below under "REGULAR EXPRESSION 67 1.1.1.3 tron TABLES" or "TCP-BASED TABLES". 68 1.1 tron 69 1.1.1.8 christos <b><a name="case_folding">CASE FOLDING</a></b> 70 1.1.1.3 tron The search string is folded to lowercase before database lookup. As of 71 1.1.1.3 tron Postfix 2.3, the search string is not case folded with database types 72 1.1.1.3 tron 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 73 1.1.1.3 tron lower case. 74 1.1 tron 75 1.1.1.8 christos <b><a name="table_format">TABLE FORMAT</a></b> 76 1.1 tron The input format for the <a href="postmap.1.html"><b>postmap</b>(1)</a> command is as follows: 77 1.1 tron 78 1.1 tron <i>pattern result</i> 79 1.1.1.3 tron When <i>pattern</i> matches the recipient address or domain, use the 80 1.1.1.3 tron corresponding <i>result</i>. 81 1.1 tron 82 1.1 tron blank lines and comments 83 1.1.1.3 tron Empty lines and whitespace-only lines are ignored, as are lines 84 1.1.1.3 tron whose first non-whitespace character is a `#'. 85 1.1 tron 86 1.1 tron multi-line text 87 1.1.1.3 tron A logical line starts with non-whitespace text. A line that 88 1.1.1.3 tron starts with whitespace continues a logical line. 89 1.1.1.3 tron 90 1.1.1.3 tron The <i>pattern</i> specifies an email address, a domain name, or a domain name 91 1.1.1.6 christos hierarchy, as described in section "TABLE SEARCH ORDER". 92 1.1.1.3 tron 93 1.1.1.3 tron The <i>result</i> is of the form <i>transport:nexthop</i> and specifies how or where 94 1.1.1.3 tron to deliver mail. This is described in section "RESULT FORMAT". 95 1.1 tron 96 1.1.1.8 christos <b><a name="table_search_order">TABLE SEARCH ORDER</a></b> 97 1.1.1.3 tron With lookups from indexed files such as DB or DBM, or from networked 98 1.1.1.3 tron tables such as NIS, LDAP or SQL, patterns are tried in the order as 99 1.1.1.3 tron listed below: 100 1.1 tron 101 1.1 tron <i>user+extension@domain transport</i>:<i>nexthop</i> 102 1.1.1.3 tron Deliver mail for <i>user+extension@domain</i> through <i>transport</i> to <i>nex-</i> 103 1.1.1.3 tron <i>thop</i>. 104 1.1 tron 105 1.1 tron <i>user@domain transport</i>:<i>nexthop</i> 106 1.1.1.3 tron Deliver mail for <i>user@domain</i> through <i>transport</i> to <i>nexthop</i>. 107 1.1 tron 108 1.1 tron <i>domain transport</i>:<i>nexthop</i> 109 1.1.1.3 tron Deliver mail for <i>domain</i> through <i>transport</i> to <i>nexthop</i>. 110 1.1 tron 111 1.1 tron <i>.domain transport</i>:<i>nexthop</i> 112 1.1.1.3 tron Deliver mail for any subdomain of <i>domain</i> through <i>transport</i> to 113 1.1.1.3 tron <i>nexthop</i>. This applies only when the string <b><a href="postconf.5.html#transport_maps">transport_maps</a></b> is not 114 1.1.1.3 tron listed in the <b><a href="postconf.5.html#parent_domain_matches_subdomains">parent_domain_matches_subdomains</a></b> configuration 115 1.1.1.3 tron setting. Otherwise, a domain name matches itself and its subdo- 116 1.1.1.3 tron mains. 117 1.1 tron 118 1.1 tron <b>*</b> <i>transport</i>:<i>nexthop</i> 119 1.1.1.3 tron The special pattern <b>*</b> represents any address (i.e. it functions 120 1.1.1.3 tron as the wild-card pattern, and is unique to Postfix transport 121 1.1.1.3 tron tables). 122 1.1.1.3 tron 123 1.1.1.3 tron Note 1: the null recipient address is looked up as 124 1.1.1.3 tron <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). 125 1.1 tron 126 1.1.1.3 tron Note 2: <i>user@domain</i> or <i>user+extension@domain</i> lookup is available in 127 1.1.1.3 tron Postfix 2.0 and later. 128 1.1 tron 129 1.1.1.8 christos <b><a name="result_format">RESULT FORMAT</a></b> 130 1.1.1.3 tron The lookup result is of the form <i>transport</i><b>:</b><i>nexthop</i>. The <i>transport</i> 131 1.1.1.3 tron field specifies a mail delivery transport such as <b>smtp</b> or <b>local</b>. The 132 1.1.1.3 tron <i>nexthop</i> field specifies where and how to deliver mail. 133 1.1.1.3 tron 134 1.1.1.3 tron The transport field specifies the name of a mail delivery transport 135 1.1.1.3 tron (the first name of a mail delivery service entry in the Postfix <a href="master.5.html"><b>mas-</b> 136 1.1.1.3 tron <b>ter.cf</b></a> file). 137 1.1.1.3 tron 138 1.1.1.5 christos The nexthop field usually specifies one recipient domain or hostname. 139 1.1.1.5 christos In the case of the Postfix SMTP/LMTP client, the nexthop field may con- 140 1.1.1.5 christos tain a list of nexthop destinations separated by comma or whitespace 141 1.1.1.5 christos (Postfix 3.5 and later). 142 1.1.1.5 christos 143 1.1.1.5 christos The syntax of a nexthop destination is transport dependent. With SMTP, 144 1.1.1.5 christos specify a service on a non-default port as <i>host</i>:<i>service</i>, and disable MX 145 1.1.1.5 christos (mail exchanger) DNS lookups with [<i>host</i>] or [<i>host</i>]:<i>port</i>. The [] form is 146 1.1.1.5 christos required when you specify an IP address instead of a hostname. 147 1.1.1.3 tron 148 1.1.1.5 christos A null <i>transport</i> and null <i>nexthop</i> field means "do not change": use the 149 1.1.1.3 tron delivery transport and nexthop information that would be used when the 150 1.1.1.3 tron entire transport table did not exist. 151 1.1 tron 152 1.1.1.3 tron A non-null <i>transport</i> field with a null <i>nexthop</i> field resets the nexthop 153 1.1.1.3 tron information to the recipient domain. 154 1.1 tron 155 1.1.1.3 tron A null <i>transport</i> field with non-null <i>nexthop</i> field does not modify the 156 1.1.1.3 tron transport information. 157 1.1 tron 158 1.1.1.8 christos <b><a name="examples">EXAMPLES</a></b> 159 1.1.1.3 tron In order to deliver internal mail directly, while using a mail relay 160 1.1.1.3 tron for all other mail, specify a null entry for internal destinations (do 161 1.1.1.3 tron not change the delivery transport or the nexthop information) and spec- 162 1.1.1.3 tron ify a wildcard for all other destinations. 163 1.1 tron 164 1.1 tron <b>my.domain :</b> 165 1.1 tron <b>.my.domain :</b> 166 1.1 tron <b>* <a href="smtp.8.html">smtp</a>:outbound-relay.my.domain</b> 167 1.1 tron 168 1.1.1.3 tron In order to send mail for <b>example.com</b> and its subdomains via the <b>uucp</b> 169 1.1.1.3 tron transport to the UUCP host named <b>example</b>: 170 1.1 tron 171 1.1 tron <b>example.com uucp:example</b> 172 1.1 tron <b>.example.com uucp:example</b> 173 1.1 tron 174 1.1.1.3 tron When no nexthop host name is specified, the destination domain name is 175 1.1.1.3 tron used instead. For example, the following directs mail for <i>user</i>@<b>exam-</b> 176 1.1.1.3 tron <b>ple.com</b> via the <b>slow</b> transport to a mail exchanger for <b>example.com</b>. 177 1.1.1.3 tron The <b>slow</b> transport could be configured to run at most one delivery 178 1.1.1.3 tron process at a time: 179 1.1 tron 180 1.1 tron <b>example.com slow:</b> 181 1.1 tron 182 1.1.1.3 tron When no transport is specified, Postfix uses the transport that matches 183 1.1.1.3 tron the address domain class (see DESCRIPTION above). The following sends 184 1.1.1.3 tron all mail for <b>example.com</b> and its subdomains to host <b>gateway.exam-</b> 185 1.1.1.3 tron <b>ple.com</b>: 186 1.1 tron 187 1.1 tron <b>example.com :[gateway.example.com]</b> 188 1.1 tron <b>.example.com :[gateway.example.com]</b> 189 1.1 tron 190 1.1.1.3 tron In the above example, the [] suppress MX lookups. This prevents mail 191 1.1.1.3 tron routing loops when your machine is primary MX host for <b>example.com</b>. 192 1.1 tron 193 1.1.1.5 christos In the case of delivery via SMTP or LMTP, one may specify <i>host</i>:<i>service</i> 194 1.1.1.3 tron instead of just a host: 195 1.1 tron 196 1.1 tron <b>example.com <a href="smtp.8.html">smtp</a>:bar.example:2025</b> 197 1.1 tron 198 1.1.1.3 tron This directs mail for <i>user</i>@<b>example.com</b> to host <b>bar.example</b> port <b>2025</b>. 199 1.1.1.3 tron Instead of a numerical port a symbolic name may be used. Specify [] 200 1.1.1.3 tron around the hostname if MX lookups must be disabled. 201 1.1 tron 202 1.1.1.5 christos Deliveries via SMTP or LMTP support multiple destinations (Postfix >= 203 1.1.1.5 christos 3.5): 204 1.1.1.5 christos 205 1.1.1.5 christos <b>example.com <a href="smtp.8.html">smtp</a>:bar.example, foo.example</b> 206 1.1.1.5 christos 207 1.1.1.5 christos This tries to deliver to <b>bar.example</b> before trying to deliver to 208 1.1.1.5 christos <b>foo.example</b>. 209 1.1.1.5 christos 210 1.1 tron The error mailer can be used to bounce mail: 211 1.1 tron 212 1.1 tron <b>.example.com <a href="error.8.html">error</a>:mail for *.example.com is not deliverable</b> 213 1.1 tron 214 1.1.1.3 tron This causes all mail for <i>user</i>@<i>anything</i><b>.example.com</b> to be bounced. 215 1.1 tron 216 1.1.1.8 christos <b><a name="regular_expression_tables">REGULAR EXPRESSION TABLES</a></b> 217 1.1.1.3 tron This section describes how the table lookups change when the table is 218 1.1.1.3 tron given in the form of regular expressions. For a description of regular 219 1.1.1.3 tron 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>. 220 1.1.1.3 tron 221 1.1.1.3 tron Each pattern is a regular expression that is applied to the entire 222 1.1.1.3 tron address being looked up. Thus, <i>some.domain.hierarchy</i> is not looked up 223 1.1.1.3 tron via its parent domains, nor is <i>user+foo@domain</i> looked up as 224 1.1.1.3 tron <i>user@domain</i>. 225 1.1.1.3 tron 226 1.1.1.3 tron Patterns are applied in the order as specified in the table, until a 227 1.1.1.3 tron pattern is found that matches the search string. 228 1.1.1.3 tron 229 1.1.1.3 tron The <a href="trivial-rewrite.8.html"><b>trivial-rewrite</b>(8)</a> server disallows regular expression substitution 230 1.1.1.3 tron of $1 etc. in regular expression lookup tables, because that could open 231 1.1.1.3 tron a security hole (Postfix version 2.3 and later). 232 1.1 tron 233 1.1.1.8 christos <b><a name="tcp-based_tables">TCP-BASED TABLES</a></b> 234 1.1.1.3 tron This section describes how the table lookups change when lookups are 235 1.1.1.3 tron directed to a TCP-based server. For a description of the TCP 236 1.1.1.3 tron client/server lookup protocol, see <a href="tcp_table.5.html"><b>tcp_table</b>(5)</a>. This feature is not 237 1.1.1.3 tron available up to and including Postfix version 2.4. 238 1.1.1.3 tron 239 1.1.1.3 tron Each lookup operation uses the entire recipient address once. Thus, 240 1.1.1.3 tron <i>some.domain.hierarchy</i> is not looked up via its parent domains, nor is 241 1.1.1.3 tron <i>user+foo@domain</i> looked up as <i>user@domain</i>. 242 1.1 tron 243 1.1 tron Results are the same as with indexed file lookups. 244 1.1 tron 245 1.1.1.8 christos <b><a name="configuration_parameters">CONFIGURATION PARAMETERS</a></b> 246 1.1.1.3 tron The following <a href="postconf.5.html"><b>main.cf</b></a> parameters are especially relevant. The text 247 1.1.1.3 tron below provides only a parameter summary. See <a href="postconf.5.html"><b>postconf</b>(5)</a> for more 248 1.1.1.3 tron details including examples. 249 1.1 tron 250 1.1.1.5 christos <b><a href="postconf.5.html#empty_address_recipient">empty_address_recipient</a> (MAILER-DAEMON)</b> 251 1.1.1.5 christos The recipient of mail addressed to the null address. 252 1.1 tron 253 1.1.1.5 christos <b><a href="postconf.5.html#parent_domain_matches_subdomains">parent_domain_matches_subdomains</a> (see 'postconf -d' output)</b> 254 1.1.1.5 christos A list of Postfix features where the pattern "example.com" also 255 1.1.1.5 christos matches subdomains of example.com, instead of requiring an 256 1.1.1.5 christos explicit ".example.com" pattern. 257 1.1.1.5 christos 258 1.1.1.5 christos <b><a href="postconf.5.html#transport_maps">transport_maps</a> (empty)</b> 259 1.1.1.5 christos Optional lookup tables with mappings from recipient address to 260 1.1.1.5 christos (message delivery transport, next-hop destination). 261 1.1 tron 262 1.1.1.8 christos <b><a name="see_also">SEE ALSO</a></b> 263 1.1 tron <a href="trivial-rewrite.8.html">trivial-rewrite(8)</a>, rewrite and resolve addresses 264 1.1 tron <a href="master.5.html">master(5)</a>, <a href="master.5.html">master.cf</a> file format 265 1.1 tron <a href="postconf.5.html">postconf(5)</a>, configuration parameters 266 1.1 tron <a href="postmap.1.html">postmap(1)</a>, Postfix lookup table manager 267 1.1 tron 268 1.1.1.8 christos <b><a name="readme_files">README FILES</a></b> 269 1.1 tron <a href="ADDRESS_REWRITING_README.html">ADDRESS_REWRITING_README</a>, address rewriting guide 270 1.1 tron <a href="DATABASE_README.html">DATABASE_README</a>, Postfix lookup table overview 271 1.1 tron <a href="FILTER_README.html">FILTER_README</a>, external content filter 272 1.1 tron 273 1.1.1.8 christos <b><a name="license">LICENSE</a></b> 274 1.1.1.3 tron The Secure Mailer license must be distributed with this software. 275 1.1 tron 276 1.1 tron <b>AUTHOR(S)</b> 277 1.1 tron Wietse Venema 278 1.1 tron IBM T.J. Watson Research 279 1.1 tron P.O. Box 704 280 1.1 tron Yorktown Heights, NY 10598, USA 281 1.1 tron 282 1.1.1.4 christos Wietse Venema 283 1.1.1.4 christos Google, Inc. 284 1.1.1.4 christos 111 8th Avenue 285 1.1.1.4 christos New York, NY 10011, USA 286 1.1.1.4 christos 287 1.1 tron TRANSPORT(5) 288 1.1 tron </pre> </body> </html> 289
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