#++
# NAME
#	transport 5
# SUMMARY
#	Postfix transport table format
# SYNOPSIS
#	\fBpostmap /etc/postfix/transport\fR
#
#	\fBpostmap -q "\fIstring\fB" /etc/postfix/transport\fR
#
#	\fBpostmap -q - /etc/postfix/transport <\fIinputfile\fR
# DESCRIPTION
#	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 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".
# CASE FOLDING
# .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.
# TABLE FORMAT
# .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 LOOKUP".
#
#	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".
# TABLE SEARCH ORDER
# .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.
# RESULT FORMAT
# .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 interpretation of the nexthop field is transport
#	dependent. In the case of 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 result 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.
# EXAMPLES
# .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, one may specify
#	\fIhostname\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.
#
#	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.
# REGULAR EXPRESSION TABLES
# .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).
# TCP-BASED TABLES
# .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.
# CONFIGURATION PARAMETERS
# .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\fR
#	The address that is looked up instead of the null sender address.
# .IP \fBparent_domain_matches_subdomains\fR
#	List of Postfix features that use \fIdomain.tld\fR patterns
#	to match \fIsub.domain.tld\fR (as opposed to
#	requiring \fI.domain.tld\fR patterns).
# .IP \fBtransport_maps\fR
#	List of transport lookup tables.
# SEE ALSO
#	trivial-rewrite(8), rewrite and resolve addresses
#	master(5), master.cf file format
#	postconf(5), configuration parameters
#	postmap(1), Postfix lookup table manager
# README FILES
# .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
# LICENSE
# .ad
# .fi
#	The Secure Mailer license must be distributed with this software.
# AUTHOR(S)
#	Wietse Venema
#	IBM T.J. Watson Research
#	P.O. Box 704
#	Yorktown Heights, NY 10598, USA
#--
