Manual browser: transport(5)
|TRANSPORT(5)||File Formats Manual||TRANSPORT(5)|
NAMEtransport - Postfix transport table format
postmap -q "string" /etc/postfix/transport
postmap -q - /etc/postfix/transport <inputfile
The optional transport(5) table specifies a mapping from email addresses to message delivery transports and next-hop destinations. Message delivery transports such as local or smtp are defined in the master.cf file, and next-hop destinations are typically hosts or domain names. The table is searched by the trivial-rewrite(8) daemon.
- local_transport (default: local:$myhostname)
- This is the default for final delivery to domains listed with mydestination, and for [ipaddress] destinations that match $inet_interfaces or $proxy_interfaces. The default nexthop destination is the MTA hostname.
- virtual_transport (default: virtual:)
- This is the default for final delivery to domains listed with virtual_mailbox_domains. The default nexthop destination is the recipient domain.
- relay_transport (default: relay:)
- This is the default for remote delivery to domains listed with relay_domains. In order of decreasing precedence, the nexthop destination is taken from relay_transport, sender_dependent_relayhost_maps, relayhost, or from the recipient domain.
- default_transport (default: smtp:)
- This is the default for remote delivery to other destinations. In order of decreasing precedence, the nexthop destination is taken from sender_dependent_default_transport_maps, default_transport, sender_dependent_relayhost_maps, relayhost, or from the recipient domain.
Normally, the transport(5) table is specified as a text file that serves as input to the postmap(1) command. The result, an indexed file in dbm or db format, is used for fast searching by the mail system. Execute the command " postmap /etc/postfix/transport" to rebuild an indexed file after changing the corresponding transport table.
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.
The input format for the postmap(1) command is as follows:
- pattern result
- When pattern matches the recipient address or domain, use the corresponding result.
- blank lines and comments
- Empty lines and whitespace-only lines are ignored, as are lines whose first non-whitespace character is a `#'.
- multi-line text
- A logical line starts with non-whitespace text. A line that starts with whitespace continues a logical line.
The pattern specifies an email address, a domain name, or a domain name hierarchy, as described in section "TABLE LOOKUP".
TABLE SEARCH ORDER
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:
- user+extension@domain transport:nexthop
- Deliver mail for user+extension@domain through transport to nexthop.
- user@domain transport:nexthop
- Deliver mail for user@domain through transport to nexthop.
- domain transport:nexthop
- Deliver mail for domain through transport to nexthop.
- .domain transport:nexthop
- Deliver mail for any subdomain of domain through transport to nexthop. This applies only when the string transport_maps is not listed in the parent_domain_matches_subdomains configuration setting. Otherwise, a domain name matches itself and its subdomains.
- * transport:nexthop
- The special pattern * represents any address (i.e. it functions as the wild-card pattern, and is unique to Postfix transport tables).
Note 1: the null recipient address is looked up as $empty_address_recipient@$myhostname (default: mailer-daemon@hostname).
The lookup result is of the form transport:nexthop. The transport field specifies a mail delivery transport such as smtp or local. The nexthop field specifies where and how to deliver mail.
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.
.example.com error:mail for *.example.com is not deliverable
REGULAR EXPRESSION TABLES
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 regexp_table(5) or pcre_table(5).
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 tcp_table(5). This feature is not available up to and including Postfix version 2.4.
The following main.cf parameters are especially relevant. The text below provides only a parameter summary. See postconf(5) for more details including examples.
- The address that is looked up instead of the null sender address.
- List of Postfix features that use domain.tld patterns to match sub.domain.tld (as opposed to requiring .domain.tld patterns).
- List of transport lookup tables.
trivial-rewrite(8), rewrite and resolve addresses
master(5), master.cf file format
postconf(5), configuration parameters
postmap(1), Postfix lookup table manager
Use "postconf readme_directory" or " postconf html_directory" to locate this information.
ADDRESS_REWRITING_README, address rewriting guide
DATABASE_README, Postfix lookup table overview
FILTER_README, external content filter
The Secure Mailer license must be distributed with this software.
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA