.TH ALIASES 5 .ad .fi .SH NAME aliases \- format of the Postfix alias database .SH SYNOPSIS .na .nf .fi \fBnewaliases\fR .SH DESCRIPTION .ad .fi The \fBaliases\fR table provides a system-wide mechanism to redirect mail for local recipients. The redirections are processed by the Postfix \fBlocal\fR(8) delivery agent. Normally, the \fBaliases\fR table is specified as a text file that serves as input to the \fBpostalias\fR(1) command. The result, an indexed file in \fBdbm\fR or \fBdb\fR format, is used for fast lookup by the mail system. Execute the command \fBnewaliases\fR in order to rebuild the indexed file after changing the Postfix alias database. The input and output file formats are expected to be compatible 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 \fB.forward\fR files in their home directory. Lines in per-user \fB.forward\fR files have the same syntax as the right-hand side of \fBaliases\fR entries. The format of the alias database input file is as follows: .IP \(bu An alias definition has the form .sp .ti +5 \fIname\fR: \fIvalue1\fR, \fIvalue2\fR, \fI...\fR .IP \(bu Empty lines and whitespace-only lines are ignored, as are lines whose first non-whitespace character is a `#'. .IP \(bu A logical line starts with non-whitespace text. A line that starts with whitespace continues a logical line. .PP The \fIname\fR is a local address (no domain part). Use double quotes when the name contains any special characters such as whitespace, `#', `:', or `@'. The \fIname\fR is folded to lowercase, in order to make database lookups case insensitive. .PP In addition, when an alias exists for \fBowner-\fIname\fR, 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. .PP The \fIvalue\fR contains one or more of the following: .IP \fIaddress\fR Mail is forwarded to \fIaddress\fR, which is compatible with the RFC 822 standard. .IP \fI/file/name\fR Mail is appended to \fI/file/name\fR. See \fBlocal\fR(8) for details of delivery to file. Delivery is not limited to regular files. For example, to dispose of unwanted mail, deflect it to \fB/dev/null\fR. .IP "|\fIcommand\fR" Mail is piped into \fIcommand\fR. Commands that contain special characters, such as whitespace, should be enclosed between double quotes. See \fBlocal\fR(8) for details of delivery to command. .sp When the command fails, a limited amount of command output is mailed back to the sender. The file \fB/usr/include/sysexits.h\fR defines the expected exit status codes. For example, use \fB|"exit 67"\fR to simulate a "user unknown" error, and \fB|"exit 0"\fR to implement an expensive black hole. .IP \fB:include:\fI/file/name\fR Mail is sent to the destinations listed in the named file. Lines in \fB:include:\fR files have the same syntax as the right-hand side of alias entries. .sp A destination can be any destination that is described in this manual page. However, delivery to "|\fIcommand\fR" and \fI/file/name\fR is disallowed by default. To enable, edit the \fBallow_mail_to_commands\fR and \fBallow_mail_to_files\fR configuration parameters. .SH ADDRESS EXTENSION .na .nf .ad .fi When alias database search fails, and the recipient localpart contains the optional recipient delimiter (e.g., \fIuser+foo\fR), the search is repeated for the unextended address (e.g., \fIuser\fR). .SH CONFIGURATION PARAMETERS .na .nf .ad .fi The following \fBmain.cf\fR parameters are especially relevant to this topic. See the Postfix \fBmain.cf\fR file for syntax details and for default values. Use the \fBpostfix reload\fR command after a configuration change. .IP \fBalias_maps\fR List of alias databases. .IP \fBallow_mail_to_commands\fR Restrict the usage of mail delivery to external command. .IP \fBallow_mail_to_files\fR Restrict the usage of mail delivery to external file. .IP \fBexpand_owner_alias\fR When delivering to an alias that has an \fBowner-\fR companion alias, set the envelope sender address to the right-hand side of the owner alias, instead using of the left-hand side address. .IP \fBowner_request_special\fR Give special treatment to \fBowner-\fIxxx\fR and \fIxxx\fB-request\fR addresses. .IP \fBrecipient_delimiter\fR Delimiter that separates recipients from address extensions. .SH BUGS .ad .fi Regular expression alias lookup tables are allowed, but substitution of $1 etc. is forbidden because that would open a security loophole. .SH STANDARDS .na .nf RFC 822 (ARPA Internet Text Messages) .SH SEE ALSO .na .nf local(8) local delivery agent newaliases(1) alias database management regexp_table(5) POSIX regular expression table format pcre_table(5) Perl Compatible Regular Expression table format .SH LICENSE .na .nf .ad .fi The Secure Mailer license must be distributed with this software. .SH AUTHOR(S) .na .nf Wietse Venema IBM T.J. Watson Research P.O. Box 704 Yorktown Heights, NY 10598, USA