Provided by: postfix_3.10.2-1ubuntu2_amd64 bug

NAME

       aliases - Postfix local alias database format

SYNOPSIS

       newaliases

       postalias -q name [file-type]:[file-name]

DESCRIPTION

       The  optional  aliases(5)  table  (alias_maps)  redirects mail for local recipients. The redirections are
       processed by the Postfix local(8) delivery agent. This table is always searched  with  an  email  address
       localpart (no domain portion).

       This  is  unlike  virtual(5)  aliasing  (virtual_alias_maps)  which  applies to all recipients: local(8),
       virtual, and remote, and which is implemented by the cleanup(8) daemon. That table is often searched with
       a full email address (including domain).

       Normally, the aliases(5) table is specified as a text file that  serves  as  input  to  the  postalias(1)
       command.  The  result,  an  indexed file in dbm or db format, is used for fast lookup by the mail system.
       Execute the command newaliases in order to rebuild the indexed file  after  changing  the  Postfix  alias
       database.

       When  the  table  is  provided via other means such as NIS, LDAP or SQL, the same lookups are done as for
       ordinary indexed files.

       Alternatively, the table can be provided as a regular-expression map where patterns are given as  regular
       expressions.  In  this  case,  the  lookups are done in a slightly different way as described below under
       "REGULAR EXPRESSION TABLES".

       Users can control delivery of their own mail by setting up .forward files in their home directory.  Lines
       in per-user .forward files have the same syntax as the right-hand side of aliases(5) entries.

       The format of the alias database input file is as follows:

       •      An alias definition has the form

                   name: value1, value2, ...

       •      Empty lines and whitespace-only lines  are  ignored,  as  are  lines  whose  first  non-whitespace
              character is a `#'.

       •      A  logical  line  starts  with non-whitespace text. A line that starts with whitespace continues a
              logical line.

       The name is a local address (no domain part).  Use double quotes  when  the  name  contains  any  special
       characters  such  as  whitespace,  `#',  `:',  or  `@'. The name is folded to lowercase, in order to make
       database lookups case insensitive.

       In addition, when an alias exists for owner-name, this will override the envelope sender address, so that
       delivery diagnostics are directed to owner-name, instead of the originator of the message  (for  details,
       see  owner_request_special,  expand_owner_alias and reset_owner_alias).  This is typically used to direct
       delivery errors to the maintainer 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 value contains one or more of the following:

       address
              Mail is forwarded to address, which is compatible with the RFC 822 standard.

       /file/name
              Mail  is  appended  to /file/name. For details on how a file is written see the sections "EXTERNAL
              FILE DELIVERY" and "DELIVERY RIGHTS" in the local(8) documentation.  Delivery is  not  limited  to
              regular files.  For example, to dispose of unwanted mail, deflect it to /dev/null.

       |command
              Mail  is  piped into command. Commands that contain special characters, such as whitespace, should
              be enclosed between double quotes. For details on how a command is executed see "EXTERNAL  COMMAND
              DELIVERY" and "DELIVERY RIGHTS" in the local(8) documentation.

              When the command fails, a limited amount of command output is mailed back to the sender.  The file
              /usr/include/sysexits.h  defines  the  expected  exit status codes. For example, use "|exit 67" to
              simulate a "user unknown" error, and "|exit 0" to implement an expensive black hole.

       :include:/file/name
              Mail is sent to the destinations listed in the named file.  Lines in :include: files have the same
              syntax as the right-hand side of aliases(5) entries.

              A destination can be any destination that is described in this manual page. However,  delivery  to
              "|command" and /file/name is disallowed by default. To enable, edit the allow_mail_to_commands and
              allow_mail_to_files configuration parameters.

ADDRESS EXTENSION

       When  alias  database search fails, and the recipient localpart contains the optional recipient delimiter
       (e.g., user+foo), the search is repeated for the unextended address (e.g., user).

       The propagate_unmatched_extensions parameter controls whether an unmatched address  extension  (+foo)  is
       propagated to the result of table lookup.

CASE FOLDING

       The local(8) delivery agent always folds the search string to lowercase before database lookup.

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). NOTE: these formats do not use ":" at the end of a pattern.

       Each  regular  expression  is  applied to the entire search string. Thus, a search string user+foo is not
       broken up into user and foo.

       Regular expressions are applied in the order as specified in the table, until  a  regular  expression  is
       found that matches the search string.

       Lookup  results  are the same as with indexed file lookups.  For security reasons there is no support for
       $1, $2 etc. substring interpolation.

SECURITY

       The local(8) delivery agent disallows regular expression substitution of $1 etc. in  alias_maps,  because
       that would open a security hole.

       The  local(8)  delivery  agent  will  silently  ignore  requests  to  use  the  proxymap(8) server within
       alias_maps. Instead it will open the table directly.  Before Postfix version 2.2, the  local(8)  delivery
       agent will terminate with a fatal error.

CONFIGURATION PARAMETERS

       The  following  main.cf  parameters  are  especially  relevant.  The text below provides only a parameter
       summary. See postconf(5) for more details including examples.

       alias_database (see 'postconf -d' output)
              The alias databases for local(8) delivery that are updated with  "newaliases"  or  with  "sendmail
              -bi".

       alias_maps (see 'postconf -d' output)
              Optional lookup tables that are searched only with an email address localpart (no domain) and that
              apply  only to local(8) recipients; this is unlike virtual_alias_maps that are often searched with
              a full email address (including domain) and that apply to all recipients: local(8),  virtual,  and
              remote.

       allow_mail_to_commands (alias, forward)
              Restrict local(8) mail delivery to external commands.

       allow_mail_to_files (alias, forward)
              Restrict local(8) mail delivery to external files.

       expand_owner_alias (no)
              When  delivering  to  an  alias "aliasname" that has an "owner-aliasname" companion alias, set the
              envelope sender address to the expansion of the "owner-aliasname" alias.

       propagate_unmatched_extensions (canonical, virtual)
              What address lookup tables copy an address extension from the lookup key to the lookup result.

       owner_request_special (yes)
              Enable special treatment for owner-listname entries  in  the  aliases(5)  file,  and  don't  split
              owner-listname and listname-request address localparts when the recipient_delimiter is set to "-".

       recipient_delimiter (empty)
              The  set of characters that can separate an email address localpart, user name, or a .forward file
              name from its extension.

       Available in Postfix version 2.3 and later:

       frozen_delivered_to (yes)
              Update   the   local(8)   delivery   agent's   idea   of   the    Delivered-To:    address    (see
              prepend_delivered_header)  only  once,  at  the  start  of  a  delivery attempt; do not update the
              Delivered-To: address while expanding aliases or .forward files.

STANDARDS

       RFC 822 (ARPA Internet Text Messages)

SEE ALSO

       local(8), local delivery agent
       newaliases(1), create/update alias database
       postalias(1), create/update alias database
       postconf(5), configuration parameters

README FILES

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

LICENSE

       The Secure Mailer license must be distributed with this software.

AUTHOR(S)

       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

                                                                                                      ALIASES(5)