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Diffstat (limited to 'man/man5/transport.5')
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diff --git a/man/man5/transport.5 b/man/man5/transport.5 new file mode 100644 index 0000000..223b958 --- /dev/null +++ b/man/man5/transport.5 @@ -0,0 +1,335 @@ +.TH TRANSPORT 5 +.ad +.fi +.SH NAME +transport +\- +Postfix transport table format +.SH "SYNOPSIS" +.na +.nf +\fBpostmap /etc/postfix/transport\fR + +\fBpostmap \-q "\fIstring\fB" /etc/postfix/transport\fR + +\fBpostmap \-q \- /etc/postfix/transport <\fIinputfile\fR +.SH DESCRIPTION +.ad +.fi +The optional \fBtransport\fR(5) table specifies a mapping from email +addresses to message delivery transports and next\-hop destinations. +Message delivery transports such as \fBlocal\fR or \fBsmtp\fR +are defined in the \fBmaster.cf\fR file, and next\-hop +destinations are typically hosts or domain names. The +table is searched by the \fBtrivial\-rewrite\fR(8) daemon. + +This mapping overrides the default \fItransport\fR:\fInexthop\fR +selection that is built into Postfix: +.IP "\fBlocal_transport (default: local:$myhostname)\fR" +This is the default for final delivery to domains listed +with \fBmydestination\fR, and for [\fIipaddress\fR] +destinations that match \fB$inet_interfaces\fR or +\fB$proxy_interfaces\fR. The default \fInexthop\fR destination +is the MTA hostname. +.IP "\fBvirtual_transport (default: virtual:)\fR" +This is the default for final delivery to domains listed +with \fBvirtual_mailbox_domains\fR. The default \fInexthop\fR +destination is the recipient domain. +.IP "\fBrelay_transport (default: relay:)\fR" +This is the default for remote delivery to domains listed +with \fBrelay_domains\fR. In order of decreasing precedence, +the \fInexthop\fR destination is taken from \fBrelay_transport\fR, +\fBsender_dependent_relayhost_maps\fR, \fBrelayhost\fR, or from the +recipient domain. +.IP "\fBdefault_transport (default: smtp:)\fR" +This is the default for remote delivery to other destinations. +In order of decreasing precedence, the \fInexthop\fR +destination is taken from \fBsender_dependent_default_transport_maps, +\fBdefault_transport\fR, \fBsender_dependent_relayhost_maps\fR, +\fBrelayhost\fR, or from the recipient domain. +.PP +Normally, the \fBtransport\fR(5) table is specified as a text file +that serves as input to the \fBpostmap\fR(1) command. +The result, an indexed file in \fBdbm\fR or \fBdb\fR format, is used +for fast searching by the mail system. Execute the command +"\fBpostmap /etc/postfix/transport\fR" to rebuild an indexed +file after changing the corresponding transport table. + +When the table is provided via other means such as NIS, LDAP +or SQL, the same lookups are done as for ordinary indexed files. + +Alternatively, the table can be provided as a regular\-expression +map where patterns are given as regular expressions, or lookups +can be directed to a TCP\-based server. In those case, the lookups +are done in a slightly different way as described below under +"REGULAR EXPRESSION TABLES" or "TCP\-BASED TABLES". +.SH "CASE FOLDING" +.na +.nf +.ad +.fi +The search string is folded to lowercase before database +lookup. As of Postfix 2.3, the search string is not case +folded with database types such as regexp: or pcre: whose +lookup fields can match both upper and lower case. +.SH "TABLE FORMAT" +.na +.nf +.ad +.fi +The input format for the \fBpostmap\fR(1) command is as follows: +.IP "\fIpattern result\fR" +When \fIpattern\fR matches the recipient address or domain, use the +corresponding \fIresult\fR. +.IP "blank lines and comments" +Empty lines and whitespace\-only lines are ignored, as +are lines whose first non\-whitespace character is a `#'. +.IP "multi\-line text" +A logical line starts with non\-whitespace text. A line that +starts with whitespace continues a logical line. +.PP +The \fIpattern\fR specifies an email address, a domain name, or +a domain name hierarchy, as described in section "TABLE +SEARCH ORDER". + +The \fIresult\fR is of the form \fItransport:nexthop\fR and +specifies how or where to deliver mail. This is described in +section "RESULT FORMAT". +.SH "TABLE SEARCH ORDER" +.na +.nf +.ad +.fi +With lookups from indexed files such as DB or DBM, or from networked +tables such as NIS, LDAP or SQL, patterns are tried in the order as +listed below: +.IP "\fIuser+extension@domain transport\fR:\fInexthop\fR" +Deliver mail for \fIuser+extension@domain\fR through +\fItransport\fR to +\fInexthop\fR. +.IP "\fIuser@domain transport\fR:\fInexthop\fR" +Deliver mail for \fIuser@domain\fR through \fItransport\fR to +\fInexthop\fR. +.IP "\fIdomain transport\fR:\fInexthop\fR" +Deliver mail for \fIdomain\fR through \fItransport\fR to +\fInexthop\fR. +.IP "\fI.domain transport\fR:\fInexthop\fR" +Deliver mail for any subdomain of \fIdomain\fR through +\fItransport\fR to \fInexthop\fR. This applies only when the +string \fBtransport_maps\fR is not listed in the +\fBparent_domain_matches_subdomains\fR configuration setting. +Otherwise, a domain name matches itself and its subdomains. +.IP "\fB*\fI transport\fR:\fInexthop\fR" +The special pattern \fB*\fR represents any address (i.e. it +functions as the wild\-card pattern, and is unique to Postfix +transport tables). +.PP +Note 1: the null recipient address is looked up as +\fB$empty_address_recipient\fR@\fB$myhostname\fR (default: +mailer\-daemon@hostname). + +Note 2: \fIuser@domain\fR or \fIuser+extension@domain\fR +lookup is available in Postfix 2.0 and later. +.SH "RESULT FORMAT" +.na +.nf +.ad +.fi +The lookup result is of the form \fItransport\fB:\fInexthop\fR. +The \fItransport\fR field specifies a mail delivery transport +such as \fBsmtp\fR or \fBlocal\fR. The \fInexthop\fR field +specifies where and how to deliver mail. + +The transport field specifies the name of a mail delivery transport +(the first name of a mail delivery service entry in the Postfix +\fBmaster.cf\fR file). + +The nexthop field usually specifies one recipient domain +or hostname. In the case of the Postfix SMTP/LMTP client, +the nexthop field may contain a list of nexthop destinations +separated by comma or whitespace (Postfix 3.5 and later). + +The syntax of a nexthop destination is transport dependent. +With SMTP, specify a service on a non\-default +port as \fIhost\fR:\fIservice\fR, and disable MX (mail exchanger) +DNS lookups with [\fIhost\fR] or [\fIhost\fR]:\fIport\fR. The [] form +is required when you specify an IP address instead of a hostname. + +A null \fItransport\fR and null \fInexthop\fR field means "do +not change": use the delivery transport and nexthop information +that would be used when the entire transport table did not exist. + +A non\-null \fItransport\fR field with a null \fInexthop\fR field +resets the nexthop information to the recipient domain. + +A null \fItransport\fR field with non\-null \fInexthop\fR field +does not modify the transport information. +.SH "EXAMPLES" +.na +.nf +.ad +.fi +In order to deliver internal mail directly, while using a +mail relay for all other mail, specify a null entry for +internal destinations (do not change the delivery transport or +the nexthop information) and specify a wildcard for all other +destinations. + +.nf + \fB\&my.domain :\fR + \fB\&.my.domain :\fR + \fB* smtp:outbound\-relay.my.domain\fR +.fi + +In order to send mail for \fBexample.com\fR and its subdomains +via the \fBuucp\fR transport to the UUCP host named \fBexample\fR: + +.nf + \fBexample.com uucp:example\fR + \fB\&.example.com uucp:example\fR +.fi + +When no nexthop host name is specified, the destination domain +name is used instead. For example, the following directs mail for +\fIuser\fR@\fBexample.com\fR via the \fBslow\fR transport to a mail +exchanger for \fBexample.com\fR. The \fBslow\fR transport could be +configured to run at most one delivery process at a time: + +.nf + \fBexample.com slow:\fR +.fi + +When no transport is specified, Postfix uses the transport that +matches the address domain class (see DESCRIPTION +above). The following sends all mail for \fBexample.com\fR and its +subdomains to host \fBgateway.example.com\fR: + +.nf + \fBexample.com :[gateway.example.com]\fR + \fB\&.example.com :[gateway.example.com]\fR +.fi + +In the above example, the [] suppress MX lookups. +This prevents mail routing loops when your machine is primary MX +host for \fBexample.com\fR. + +In the case of delivery via SMTP or LMTP, one may specify +\fIhost\fR:\fIservice\fR instead of just a host: + +.nf + \fBexample.com smtp:bar.example:2025\fR +.fi + +This directs mail for \fIuser\fR@\fBexample.com\fR to host \fBbar.example\fR +port \fB2025\fR. Instead of a numerical port a symbolic name may be +used. Specify [] around the hostname if MX lookups must be disabled. + +Deliveries via SMTP or LMTP support multiple destinations +(Postfix >= 3.5): + +.nf + \fBexample.com smtp:bar.example, foo.example\fR +.fi + +This tries to deliver to \fBbar.example\fR before trying +to deliver to \fBfoo.example\fR. + +The error mailer can be used to bounce mail: + +.nf + \fB\&.example.com error:mail for *.example.com is not deliverable\fR +.fi + +This causes all mail for \fIuser\fR@\fIanything\fB.example.com\fR +to be bounced. +.SH "REGULAR EXPRESSION TABLES" +.na +.nf +.ad +.fi +This section describes how the table lookups change when the table +is given in the form of regular expressions. For a description of +regular expression lookup table syntax, see \fBregexp_table\fR(5) +or \fBpcre_table\fR(5). + +Each pattern is a regular expression that is applied to the entire +address being looked up. Thus, \fIsome.domain.hierarchy\fR is not +looked up via its parent domains, +nor is \fIuser+foo@domain\fR looked up as \fIuser@domain\fR. + +Patterns are applied in the order as specified in the table, until a +pattern is found that matches the search string. + +The \fBtrivial\-rewrite\fR(8) server disallows regular +expression substitution of $1 etc. in regular expression +lookup tables, because that could open a security hole +(Postfix version 2.3 and later). +.SH "TCP-BASED TABLES" +.na +.nf +.ad +.fi +This section describes how the table lookups change when lookups +are directed to a TCP\-based server. For a description of the TCP +client/server lookup protocol, see \fBtcp_table\fR(5). +This feature is not available up to and including Postfix version 2.4. + +Each lookup operation uses the entire recipient address once. Thus, +\fIsome.domain.hierarchy\fR is not looked up via its parent domains, +nor is \fIuser+foo@domain\fR looked up as \fIuser@domain\fR. + +Results are the same as with indexed file lookups. +.SH "CONFIGURATION PARAMETERS" +.na +.nf +.ad +.fi +The following \fBmain.cf\fR parameters are especially relevant. +The text below provides only a parameter summary. See +\fBpostconf\fR(5) for more details including examples. +.IP "\fBempty_address_recipient (MAILER\-DAEMON)\fR" +The recipient of mail addressed to the null address. +.IP "\fBparent_domain_matches_subdomains (see 'postconf -d' output)\fR" +A list of Postfix features where the pattern "example.com" also +matches subdomains of example.com, +instead of requiring an explicit ".example.com" pattern. +.IP "\fBtransport_maps (empty)\fR" +Optional lookup tables with mappings from recipient address to +(message delivery transport, next\-hop destination). +.SH "SEE ALSO" +.na +.nf +trivial\-rewrite(8), rewrite and resolve addresses +master(5), master.cf file format +postconf(5), configuration parameters +postmap(1), Postfix lookup table manager +.SH "README FILES" +.na +.nf +.ad +.fi +Use "\fBpostconf readme_directory\fR" or +"\fBpostconf html_directory\fR" to locate this information. +.na +.nf +ADDRESS_REWRITING_README, address rewriting guide +DATABASE_README, Postfix lookup table overview +FILTER_README, external content filter +.SH "LICENSE" +.na +.nf +.ad +.fi +The Secure Mailer license must be distributed with this software. +.SH "AUTHOR(S)" +.na +.nf +Wietse Venema +IBM T.J. Watson Research +P.O. Box 704 +Yorktown Heights, NY 10598, USA + +Wietse Venema +Google, Inc. +111 8th Avenue +New York, NY 10011, USA |