makealiases(8)

NAME

   makealiases - Create an alias database

SYNOPSIS

   makealiases [-protocol=protocol] [-alias=filename] [-src=pathname]
               [-tmp=filename] [-chk] [-dump] [module]

DESCRIPTION

   The Courier mail server's /etc/courier/aliases.dat file is a unified
   implementation of sendmail-style address aliasing, qmail-style virtual
   domains, plus several Courier mail server-style enhancements.

   The term aliasing refers to substituting one or more addresses for
   another address. A one-to-one substitution results in the Courier mail
   server accepting mail for one address, and delivering the mail to
   another address. A one-to-many substitution results in the Courier mail
   server accepting mail for one address, and delivering a separate copy
   of the message to every address defined by the alias.

   /etc/courier/aliases.dat is a binary database file.  makealiases
   creates the binary database file by reading the aliases from plain text
   files, and makealiases creates /etc/courier/aliases.dat by default.

   makealiases creates /etc/courier/aliases.dat from one or more source
   files, which are plain text files that may be created by any text
   editor. The format of those source files is defined below. By default,
   makealiases obtains the source text from /etc/courier/aliases. If this
   is a text file, it is used verbatim. If this is a directory (the
   Courier mail server creates it as a directory by default), all the
   non-hidden files in this directory are concatenated together.

OPTIONS

   -alias=filename
       Create filename, instead of /etc/courier/aliases.dat.

   -chk
       Try to search for bad addresses used in the aliases.dat file. This
       option takes some time to complete. It does not create an
       aliases.dat file, but instead tries to check every address
       specified by the source text file. Why is this necessary? That's
       because non-delivery reports will not be sent to the sender for
       failures in delivering mail to an aliased address. This is by
       design. the Courier mail server considers aliases to be private
       mailing lists. Because non-delivery notices are not sent, bad
       addresses will not be immediately detected.

           Note
           The -chk option is really effective for addresses which are
           local, because there is no real way to determine if a remote
           mail address is valid.

   -dump
       Do not create aliases.dat, instead display the contents of the
       alias database, in plain text form. The contents will be the
       combined contents of all the source files, with all addresses
       converted to canonical format, with duplicates removed and
       sub-aliases expanded.

   -src=pathname
       Use pathname instead of /etc/courier/aliases as the source file.
       pathname can also refer to a directory. This concatenates every
       non-hidden file in the directory.

   -tmp=filename
       Use filename as a temporary file, instead of
       /etc/courier/aliases.tmp.  makealiases requires a temporary file
       for its own purposes, which is automatically removed when done.
       This temporary file MUST reside on the same filesystem as
       aliases.dat. If the -alias option specifies a file on a different
       filesystem, use this option to specify where to temporary place a
       file in the same filesystem. Because makealiases always uses the
       same name for a temporary file you cannot run more than one
       makealiases process at the same time.

   -protocol=protocol
       Use an alias list that's private to messages coming from protocol.
       See below.

   The optional module specifies the module whose rewriting rules are used
   to convert E-mail addresses into a canonical form. If not specified,
   the local module's address rewriting rules will be used.

PROTOCOL ALIASES

   Addresses in /etc/courier/aliases.dat will be checked in every message.
   Use the -protocol option to create aliases that will be checked only
   for message that are received via a specific protocol, such as ESMTP,
   UUCP, or locally-generated mail. This allows you, for example, to
   create an alias such as "everyone", which is only avaliable to locally
   generated mail, and does not work for mail received via ESMTP. The
   argument to the -protocol option is one of: esmtp, uucp, or local.

   Protocol-specific alias files are /etc/courier/aliases-protocol.dat,
   where "protocol" is the specific protocol, such as "local", "esmtp", or
   "uucp", and the source file read by makealiases would be
   /etc/courier/aliases-protocol. If the -protocol option is specified,
   makealiases will access these files instead of /etc/courier/aliases.dat
   and /etc/courier/aliases.

ALIAS SPECIFICATIONS

   The sources file used to create the binary aliases.dat database are
   plain text files that may be created using any editor.

   Each alias specification takes the following form:

       alias: address1, address2, ...

   Mail received by the Courier mail server addressed to alias will be
   delivered to the list of addresses specified. The list of addresses may
   be split across multiple lines, if the second and subsequent line
   starts with a space character.

   Lines starting with the # character are ignored, they are comments.

   alias is not restricted to be a local address. It may be any valid RFC
   2822[1] address. All addresses do not necessary have to be in a
   canonical form.

       alias: :include:/absolute/pathname

   This notation reads the list of addresses from another file,
   /absolute/pathname. This file should contain one address per line
   (comma separated addresses on the same line will also work).

       Note
       If alias refers to a local, existing, account, this account will
       never get any mail. Any mail with the account listed as recipient
       will be redirected to all the addresses specified for that alias.
       To have a copy of the mail delivered to the account, define it as
       one of the addresses in the alias itself. For example:

           larry: larry, moe, curly, shemp

       Larry will still receive his mail, but copies will will also be
       sent to Moe, Curly, and Shemp. If Larry wasn't specified in the
       alias, he would never get any mail, it will all be forwarded to
       Moe, Curly, and Shemp.

DUPLICATE ADDRESSES

   Alias definitions may refer to other alias definitions, and makealiases
   automatically incorporates addresses from other aliases. If the same
   address is listed in multiple aliases, and two or more of them are
   specified as recipients of the same message, only one copy of the
   message will be delivered to the address.

VIRTUAL DOMAINS

   The following special syntax implements a virtual domain. A virtual
   domain redirects all mail for an entire domain to one user:

       @domain: user

   This special entry results in any recipient address of the form
   foo@domain to be rewritten as user-foo@me, where me is the hostname of
   the machine, which we expect to be a local domain.

   The following examples use the alias entry "@example.com: john", and
   "domain.com" is in the control/me file. The address
   "[email protected]" becomes "[email protected]", and
   "[email protected]" becomes "[email protected]".

   The intended behavior is to use an actual account named john. As a
   result of the virtual domain address rewriting, delivery instructions
   for [email protected] can now be specified by john's
   $HOME/.courier-postmaster file, and delivery instructions for
   [email protected] may be specified by $HOME/.courier-sales-info.
   john's $HOME/.courier-default may be used to specify delivery
   instructions for any other address in the example.com domain, which
   does not have an explicit .courier file.

   If the alias entry was "@example.com: john-example", the corresponding
   files in john's $HOME directory are .courier-example-postmaster,
   .courier-example-sales-info, and .courier-example-default. See dot-
   courier(5)[2] for more information on .courier files.

       Note
       Virtual domain rewriting is NOT recursive, unlike regular aliases.
       For example:

           tom: [email protected]
           @example.com: larry

       You should explicitly expand the alias out:

           tom: larry-john

PROGRAM OR MAILBOX ALIASES

   The following notation associates an address directly with a mailbox,
   or with a program:

       info: /var/shared/info

   Messages addressed to "info" will be delivered to the mailbox or
   maildir /var/shared/info. A full pathname must be specified.

       info: | /usr/local/shared/info

   Mail addressed to "info" will be delivered to the indicated program.
   The program receives each message on standard input.

   Program/mailbox delivery notation is primarily used to support legacy
   sendmail aliases entries. This is considered to be a legacy feature,
   and new installations should create a dot-courier(5)[2] file with the
   necessary delivery instructions. In fact, aliases for programs or
   mailboxes is not directly supported by the Courier mail server's
   aliasing mechanisms. It's implemented by having the makealiases script
   automatically create a .courier file, and point the alias address to
   it.

   See dot-courier(5)[2] for more information.

       Note
       Unlike sendmail, the Courier mail server delivers as user "courier"
       (group courier) when delivering to programs or mailboxes.

UUCP VIRTUAL DOMAINS

   The following notation allows mail addressed to a certain domain to be
   forwarded via uucp:

       @domain: uucp!bang!path!

   The trailing !  tells the Courier mail server not to append a dash, so
   user@domain gets rewritten as uucp!bang!path!user, and not
   uucp!bang!path-user, which is probably not what you want.

DELIVERY STATUS NOTIFICATIONS

   An alias with only one address does not affect delivery status
   notification attributes of an E-mail message.

   An alias with multiple addresses is treated like a private mailing
   list, as defined by RFC 1894[3]. If the message requests a successful
   delivery notification, the Courier mail server generates a delivery
   status notification for the successful delivery to the aliased address,
   and each alias recipient address will have DSNs set to NEVER.

BUGS

   This has nothing to do with the Courier mail server's support for a
   Qmail-style alias account.

   owner-foo feature of sendmail's aliasing is not supported.

   the Courier mail server normally tries to eliminate duplicate addresses
   listed as recipients for the same message. Some mail servers are not
   capable of delivering messages with multiple recipients, and will
   transmit a separate copy of the same message addressed to each
   recipient. The Courier mail server can't do anything in this case. Each
   copy of the same original text is considered an individual, separate,
   message.

   Duplicate elimination can fail in certain rare circumstances, involving
   exotic features of RFC 2822[1] concerning case sensitivity.

   "@example.com: jack, jill" is allowed, but strongly discouraged under
   the penalty of law.

   Because multiple-recipient aliases are treated like private mailing
   lists, failure DSNs are turned off, and a bad recipient address is
   hardly noticed by anyone.

   The makealiases command may execute while the Courier mail server is
   running, and any changes take effect immediately. However, only one
   instance of makealiases is permitted to run at the same time.

SEE ALSO

   esmtpd(8)[4].

AUTHOR

   Sam Varshavchik
       Author

NOTES

    1. RFC 2822
       http://www.rfc-editor.org/rfc/rfc822.txt

    2. dot-courier(5)
       [set $man.base.url.for.relative.links]/dot-courier.html

    3. RFC 1894
       http://www.rfc-editor.org/rfc/rfc1894.txt

    4. esmtpd(8)
       [set $man.base.url.for.relative.links]/esmtpd.html

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