socketmap_table(5) Postfix socketmap table lookup client


postmap -q "string" socketmap:inet:host:port:name
postmap -q "string" socketmap:unix:pathname:name
postmap -q - socketmap:inet:host:port:name <inputfile
postmap -q - socketmap:unix:pathname:name <inputfile


The Postfix mail system uses optional tables for address rewriting. mail routing or policy lookup.

The Postfix socketmap client expects TCP endpoint names of the form inet:host:port:name, or UNIX-domain endpoints of the form unix:pathname:name. In both cases, name specifies the name field in a socketmap client request (see "REQUEST FORMAT" below).


Socketmaps use a simple protocol: the client sends one
request, and the server sends one reply.  Each request and
reply are sent as one netstring object.


The socketmap protocol supports only the lookup request.
The request has the following form:

name <space> key
Search the named socketmap for the specified key.

Postfix will not generate partial search keys such as domain names without one or more subdomains, network addresses without one or more least-significant octets, or email addresses without the localpart, address extension or domain portion. This behavior is also found with cidr:, pcre:, and regexp: tables.


The Postfix socketmap client requires that replies are not
longer than 100000 characters (not including the netstring
encapsulation). Replies must have the following form:
OK <space> data
The requested data was found.
NOTFOUND <space>
The requested data was not found.
TEMP <space>
TIMEOUT <space> reason
PERM <space> reason
The request failed. The reason, if non-empty, is descriptive text.


This map cannot be used for security-sensitive information,
because neither the connection nor the server are authenticated.


Use "postconf readme_directory" or
"postconf html_directory" to locate this information.
DATABASE_README, Postfix lookup table overview


The protocol limits are not yet configurable.


The Secure Mailer license must be distributed with this software.


Socketmap support was introduced with Postfix version 2.10.


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