An entry has one of the following form:
Where new_location specifies contact information such as an email address, or perhaps a street address or telephone number.
|o||Empty lines and whitespace-only lines are ignored, as are lines whose first non-whitespace character is a #.|
|o||A logical line starts with non-whitespace text. A line that starts with whitespace continues a logical line.|
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@domain Matches user@domain. This form has precedence over all other forms. user Matches user@site when site is $myorigin, when site is listed in $mydestination, or when site is listed in $inet_interfaces or $proxy_interfaces. @domain Matches other addresses in domain. This form has the lowest precedence.
When a mail address localpart contains the optional recipient delimiter (e.g., user+foo@domain), the lookup order becomes: user+foo@domain, user@domain, user+foo, user, and @domain.
This section describes how the table lookups change when the table is given in the form of regular expressions or when lookups are directed to a TCP-based server. For a description of regular expression lookup table syntax, see regexp_table(5) or pcre_table(5). For a description of the TCP client/server table lookup protocol, see tcp_table(5). This feature is not available up to and including Postfix version 2.4.
Each pattern is a regular expression that is applied to the entire address being looked up. Thus, user@domain mail addresses are not broken up into their user and @domain constituent parts, nor is user+foo broken up into user and foo.
Patterns are applied in the order as specified in the table, until a pattern is found that matches the search string.
Results are the same as with indexed file lookups, with the additional feature that parenthesized substrings from the pattern can be interpolated as $1, $2 and so on.
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.
Each lookup operation uses the entire address once. Thus, user@domain mail addresses are not broken up into their user and @domain constituent parts, nor is user+foo broken up into user and foo.
Results are the same as with indexed file lookups.
The table format does not understand quoting conventions.
The following main.cf parameters are especially relevant. The text below provides only a parameter summary. See postconf(5) for more details including examples.
relocated_maps List of lookup tables for relocated users or sites. Other parameters of interest: inet_interfaces The network interface addresses that this system receives mail on. You need to stop and start Postfix when this parameter changes. mydestination List of domains that this mail system considers local. myorigin The domain that is appended to locally-posted mail. proxy_interfaces Other interfaces that this machine receives mail on by way of a proxy agent or network address translator.
trivial-rewrite(8), address resolver postmap(1), Postfix lookup table manager postconf(5), configuration parameters
Use "postconf readme_directory" or "postconf html_directory" to locate this information.DATABASE_README, Postfix lookup table overview ADDRESS_REWRITING_README, address rewriting guide
The Secure Mailer license must be distributed with this software.
Wietse Venema IBM T.J. Watson Research P.O. Box 704 Yorktown Heights, NY 10598, USA