1ALIASES(5)                    File Formats Manual                   ALIASES(5)
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NAME

6       aliases - Postfix local alias database format
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SYNOPSIS

9       newaliases
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DESCRIPTION

12       The  aliases(5) table provides a system-wide mechanism to redirect mail
13       for local recipients. The redirections are  processed  by  the  Postfix
14       local(8) delivery agent.
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16       Normally,  the aliases(5) table is specified as a text file that serves
17       as input to the postalias(1) command. The result, an  indexed  file  in
18       dbm  or  db format, is used for fast lookup by the mail system. Execute
19       the command newaliases in order  to  rebuild  the  indexed  file  after
20       changing the Postfix alias database.
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22       The  input  and  output file formats are expected to be compatible with
23       Sendmail version 8, and are expected to be suitable for the use as  NIS
24       maps.
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26       Users  can  control  delivery  of their own mail by setting up .forward
27       files in their home directory.  Lines in per-user .forward  files  have
28       the same syntax as the right-hand side of aliases(5) entries.
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30       The format of the alias database input file is as follows:
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32       ·      An alias definition has the form
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34                   name: value1, value2, ...
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36       ·      Empty  lines and whitespace-only lines are ignored, as are lines
37              whose first non-whitespace character is a `#'.
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39       ·      A logical line starts with  non-whitespace  text.  A  line  that
40              starts with whitespace continues a logical line.
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42       The  name  is a local address (no domain part).  Use double quotes when
43       the name contains any special characters such as whitespace, `#',  `:',
44       or  `@'.  The  name  is  folded to lowercase, in order to make database
45       lookups case insensitive.
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47       In addition, when an alias exists for owner-name, delivery  diagnostics
48       are  directed to that address, instead of to the originator of the mes‐
49       sage.  This is typically used to direct delivery errors  to  the  main‐
50       tainer  of  a  mailing  list,  who is in a better position to deal with
51       mailing list delivery problems than the originator of  the  undelivered
52       mail.
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54       The value contains one or more of the following:
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56       address
57              Mail  is  forwarded to address, which is compatible with the RFC
58              822 standard.
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60       /file/name
61              Mail is appended to /file/name.  See  local(8)  for  details  of
62              delivery  to  file.   Delivery  is not limited to regular files.
63              For  example,  to  dispose  of  unwanted  mail,  deflect  it  to
64              /dev/null.
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66       |command
67              Mail  is piped into command. Commands that contain special char‐
68              acters, such as whitespace, should be  enclosed  between  double
69              quotes. See local(8) for details of delivery to command.
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71              When  the  command  fails, a limited amount of command output is
72              mailed back to the  sender.   The  file  /usr/include/sysexits.h
73              defines  the expected exit status codes. For example, use "|exit
74              67" to simulate a "user unknown" error, and "|exit 0" to  imple‐
75              ment an expensive black hole.
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77       :include:/file/name
78              Mail  is  sent  to  the  destinations  listed in the named file.
79              Lines in :include: files have the same syntax as the  right-hand
80              side of alias entries.
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82              A  destination  can be any destination that is described in this
83              manual page. However, delivery to "|command" and  /file/name  is
84              disallowed  by  default.  To enable, edit the allow_mail_to_com‐
85              mands and allow_mail_to_files configuration parameters.
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ADDRESS EXTENSION

88       When alias database search fails, and the recipient localpart  contains
89       the  optional  recipient  delimiter  (e.g.,  user+foo),  the  search is
90       repeated for the unextended address (e.g., user).
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92       The  propagate_unmatched_extensions  parameter  controls   whether   an
93       unmatched address extension (+foo) is propagated to the result of table
94       lookup.
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CASE FOLDING

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

101       The  local(8)  delivery agent disallows regular expression substitution
102       of $1 etc. in alias_maps, because that would open a security hole.
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104       The local(8) delivery agent will silently ignore requests  to  use  the
105       proxymap(8)  server  within  alias_maps. Instead it will open the table
106       directly.  Before Postfix version 2.2, the local(8) delivery agent will
107       terminate with a fatal error.
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CONFIGURATION PARAMETERS

110       The  following  main.cf  parameters  are especially relevant.  The text
111       below provides only a  parameter  summary.  See  postconf(5)  for  more
112       details including examples.
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114       alias_database
115              List  of  alias  databases that are updated by the newaliases(1)
116              command.
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118       alias_maps
119              List of alias databases queried by the local(8) delivery agent.
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121       allow_mail_to_commands
122              Restrict the usage of mail delivery to external command.
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124       allow_mail_to_files
125              Restrict the usage of mail delivery to external file.
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127       expand_owner_alias
128              When delivering to an alias that has an owner- companion  alias,
129              set  the  envelope  sender address to the right-hand side of the
130              owner alias, instead using of the left-hand side address.
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132       propagate_unmatched_extensions
133              A list of address rewriting or forwarding mechanisms that propa‐
134              gate  an  address  extension  from  the  original address to the
135              result. Specify zero or more of canonical, virtual, alias,  for‐
136              ward, include, or generic.
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138       owner_request_special
139              Give  special  treatment  to owner-listname and listname-request
140              addresses.
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142       recipient_delimiter
143              Delimiter that separates recipients from address extensions.
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145       Available in Postfix version 2.3 and later:
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147       frozen_delivered_to
148              Update the local(8) delivery agent's Delivered-To: address  (see
149              prepend_delivered_header) only once, at the start of a delivery;
150              do not update the Delivered-To: address while expanding  aliases
151              or .forward files.
152

STANDARDS

154       RFC 822 (ARPA Internet Text Messages)
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SEE ALSO

157       local(8), local delivery agent
158       newaliases(1), create/update alias database
159       postalias(1), create/update alias database
160       postconf(5), configuration parameters
161

README FILES

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

168       The Secure Mailer license must be distributed with this software.
169

AUTHOR(S)

171       Wietse Venema
172       IBM T.J. Watson Research
173       P.O. Box 704
174       Yorktown Heights, NY 10598, USA
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178                                                                    ALIASES(5)
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