NetBSD/gnu/dist/postfix/html/aliases.5.html
2002-12-24 19:39:42 +00:00

157 lines
7.0 KiB
HTML

<html> <head> </head> <body> <pre>
ALIASES(5) ALIASES(5)
<b>NAME</b>
aliases - format of the Postfix alias database
<b>SYNOPSIS</b>
<b>newaliases</b>
<b>DESCRIPTION</b>
The <b>aliases</b> table provides a system-wide mechanism to
redirect mail for local recipients. The redirections are
processed by the Postfix <a href="local.8.html"><b>local</b>(8)</a> delivery agent.
Normally, the <b>aliases</b> table is specified as a text file
that serves as input to the <a href="postalias.1.html"><b>postalias</b>(1)</a> command. The
result, an indexed file in <b>dbm</b> or <b>db</b> format, is used for
fast lookup by the mail system. Execute the command
<b>newaliases</b> in order to rebuild the indexed file after
changing the Postfix alias database.
The input and output file formats are expected to be com-
patible with Sendmail version 8, and are expected to be
suitable for the use as NIS maps.
Users can control delivery of their own mail by setting up
<b>.forward</b> files in their home directory. Lines in per-user
<b>.forward</b> files have the same syntax as the right-hand side
of <b>aliases</b> entries.
The format of the alias database input file is as follows:
<b>o</b> An alias definition has the form
<i>name</i>: <i>value1</i>, <i>value2</i>, <i>...</i>
<b>o</b> Empty lines and whitespace-only lines are ignored,
as are lines whose first non-whitespace character
is a `#'.
<b>o</b> A logical line starts with non-whitespace text. A
line that starts with whitespace continues a logi-
cal line.
The <i>name</i> is a local address (no domain part). Use double
quotes when the name contains any special characters such
as whitespace, `#', `:', or `@'. The <i>name</i> is folded to
lowercase, in order to make database lookups case insensi-
tive.
In addition, when an alias exists for <b>owner-</b><i>name</i>, delivery
diagnostics are directed to that address, instead of to
the originator. This is typically used to direct delivery
errors to the owner of a mailing list, who is in a better
position to deal with mailing list delivery problems than
the originator of the undelivered mail.
The <i>value</i> contains one or more of the following:
<i>address</i>
Mail is forwarded to <i>address</i>, which is compatible
with the <a href="http://www.faqs.org/rfcs/rfc822.html">RFC 822</a> standard.
<i>/file/name</i>
Mail is appended to <i>/file/name</i>. See <a href="local.8.html"><b>local</b>(8)</a> for
details of delivery to file. Delivery is not lim-
ited to regular files. For example, to dispose of
unwanted mail, deflect it to <b>/dev/null</b>.
|<i>command</i>
Mail is piped into <i>command</i>. Commands that contain
special characters, such as whitespace, should be
enclosed between double quotes. See <a href="local.8.html"><b>local</b>(8)</a> for
details of delivery to command.
When the command fails, a limited amount of command
output is mailed back to the sender. The file
<b>/usr/include/sysexits.h</b> defines the expected exit
status codes. For example, use <b>|"exit</b> <b>67"</b> to simu-
late a "user unknown" error, and <b>|"exit</b> <b>0"</b> to
implement an expensive black hole.
<b>:include:</b><i>/file/name</i>
Mail is sent to the destinations listed in the
named file. Lines in <b>:include:</b> files have the same
syntax as the right-hand side of alias entries.
A destination can be any destination that is
described in this manual page. However, delivery to
"|<i>command</i>" and <i>/file/name</i> is disallowed by default.
To enable, edit the <b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>commands</b> and
<b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>files</b> configuration parameters.
<b>ADDRESS</b> <b>EXTENSION</b>
When alias database search fails, and the recipient local-
part contains the optional recipient delimiter (e.g.,
<i>user+foo</i>), the search is repeated for the unextended
address (e.g., <i>user</i>).
<b>CONFIGURATION</b> <b>PARAMETERS</b>
The following <b>main.cf</b> parameters are especially relevant
to this topic. See the Postfix <b>main.cf</b> file for syntax
details and for default values. Use the <b>postfix</b> <b>reload</b>
command after a configuration change.
<b>alias</b><i>_</i><b>maps</b>
List of alias databases.
<b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>commands</b>
Restrict the usage of mail delivery to external
command.
<b>allow</b><i>_</i><b>mail</b><i>_</i><b>to</b><i>_</i><b>files</b>
Restrict the usage of mail delivery to external
file.
<b>expand</b><i>_</i><b>owner</b><i>_</i><b>alias</b>
When delivering to an alias that has an <b>owner-</b> com-
panion alias, set the envelope sender address to
the right-hand side of the owner alias, instead
using of the left-hand side address.
<b>owner</b><i>_</i><b>request</b><i>_</i><b>special</b>
Give special treatment to <b>owner-</b><i>xxx</i> and <i>xxx</i><b>-request</b>
addresses.
<b>recipient</b><i>_</i><b>delimiter</b>
Delimiter that separates recipients from address
extensions.
<b>BUGS</b>
Regular expression alias lookup tables are allowed, but
substitution of $1 etc. is forbidden because that would
open a security loophole.
<b>STANDARDS</b>
<a href="http://www.faqs.org/rfcs/rfc822.html">RFC 822</a> (ARPA Internet Text Messages)
<b>SEE</b> <b>ALSO</b>
<a href="local.8.html">local(8)</a> local delivery agent
<a href="newaliases.1.html">newaliases(1)</a> alias database management
<a href="regexp_table.5.html">regexp_table(5)</a> POSIX regular expression table format
<a href="pcre_table.5.html">pcre_table(5)</a> Perl Compatible Regular Expression table format
<b>LICENSE</b>
The Secure Mailer license must be distributed with this
software.
<b>AUTHOR(S)</b>
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA
ALIASES(5)
</pre> </body> </html>