ALIASES(5)                                                          ALIASES(5)



NAME
       aliases - format of the Postfix alias database

SYNOPSIS
       newaliases

DESCRIPTION
       The aliases table provides a system-wide mechanism to redirect mail for
       local  recipients.  The  redirections  are  processed  by  the  Postfix
       local(8) delivery agent.

       Normally,  the aliases 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.

       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 .forward
       files in their home directory.  Lines in per-user .forward  files  have
       the same syntax as the right-hand side of aliases entries.

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

       ]o      An alias definition has the form

                   name: value1, value2, ...

       ]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.

       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, 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 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.  See local(8) for details of
              delivery to file.  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  char-
              acters,  such  as  whitespace, should be enclosed between double
              quotes. See local(8) for details of delivery to command.

              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 00"" to imple-
              ment 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 alias 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  allowmailtocom-
              mands and allowmailtofiles configuration parameters.

ADRES 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).

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.

       aliasdatabase
              List  of  alias  databases that are updated by the newaliases(1)
              command.

       aliasmaps
              List of alias databases queried by the local(8) delivery  agent.

       allowmailtocommands
              Restrict the usage of mail delivery to external command.

       allowmailtofiles
              Restrict the usage of mail delivery to external file.

       expandowneralias
              When  delivering to an alias that has an owner- companion alias,
              set the envelope sender address to the right-hand  side  of  the
              owner alias, instead using of the left-hand side address.

       ownerrequestspecial
              Give  special  treatment  to owner-listname and listname-request
              addresses.

       recipientdelimiter
              Delimiter that separates recipients from address extensions.

BUGS
       Regular expression alias lookup tables are allowed, but substitution of
       $1 etc. is forbidden because that would open a security loophole.

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 readmedirectory" or "postconf htmldirectory" to locate
       this information.
       DATABASEREADME, 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



                                                                    ALIASES(5)