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makehosteddomains(8)


NAME

   makehosteddomains - Build a database of hosted domains

SYNOPSIS

   makehosteddomains

DESCRIPTION

   makehosteddomains rebuilds the contents of the
   /etc/courier/hosteddomains.dat database from the contents of
   /etc/courier/hosteddomains. This can be either a file or a directory.
   If it's a directory, the contents of all the files in this directory
   are simply concatenated.  Note that this build of courier ignores any
   files that match the regex pattern ".*.dpkg-[a-z]*" (dpkg configuration
   file handling) and ".*~" (backup files of some editors).  The
   makehosteddomains script must be run in order for any changes to
   /etc/courier/hosteddomains to take effect.

   The function of /etc/courier/hosteddomains is very similar to the one
   of /etc/courier/locals. Both configuration files specify a list of
   domains that are considered to be local domains - domains whose
   mailboxes are stored locally.

   The difference is that domains listed in /etc/courier/locals are
   removed from addresses before their mailbox is looked up. For example,
   if the domain "example.com" is listed in /etc/courier/locals, then the
   address <user@example.com> is delivered to a local mailbox named
   "user". If this domain is listed, instead, in
   /etc/courier/hosteddomains, then the address <user@example.com> is
   delivered to a local mailbox named "user@example.com". Usually you
   would use /etc/courier/locals to specify domains that correspond to
   your local system accounts, that are looked up in your system's
   password database. The /etc/courier/hosteddomains file is usually used
   when you have database-based virtual domains, that are maintained via
   an LDAP or a MySQL server. The Courier mail server's LDAP and MySQL
   authentication modules will use the full E-mail address to query the
   LDAP or MySQL server for the location of the local mailbox that
   correspond to the E-mail address. The Courier mail server's authuserdb
   authentication module can also use full E-mail addresses.

   Contents of hosteddomains
   The file /etc/courier/hosteddomains simply contains a list of domains,
   one per line, for example:

       domain.com
       example.org

   Each domain can optionally be followed by a single tab character, in
   order to specify an alias for a domain, for example:

       domain.com
       mail.domain.com<TAB>domain.com
       example.com<TAB>domain.com

   First, we list the domain "domain.com" as a hosted domain. Then, we
   also list the domain "mail.domain.com", which is an alias for
   domain.com. The Courier mail server will take any address of the form
   <address@mail.domain.com>, rewrite it as <address@domain.com>, and
   attempt to deliver the mail to a local mailbox for that name. The third
   entry does the same for "example.com"; mail addressed to
   <address@example.com> is delivered to the local mailbox
   <address@domain.com>.

   alias@hosteddomain
   This is a special local mail delivery rule for hosteddomain-listed
   domains. This rule allows the Courier mail server accept mail to any
   address@hosteddomain, where "hosteddomain" is a domain listed in the
   hosteddomains file, but there is no corresponding account for
   address@hosteddomain. To provide delivery instructions for any
   non-existing address in a hosteddomain-listed domain:

   1) Create the local address alias@hosteddomain. For example, if the
   hosteddomains file contains "example.com", create the local account
   alias@example.com. This should be a normal account, with its own home
   directory, userid and groupid.

   2) Create $HOME/.courier-default file in this account, containing the
   delivery instructions. See the dot-courier(5)[1] manual page for
   available delivery instructions.

   NOTE that alias@example.com must be a real account, not a mail alias.
   If you want to forward alias@example.com to another address, put
   forwarding instructions in the .courier-default file. However,
   alias@example.com can be a clone of another account (with the same home
   directory, userid, and groupid).

   "WILDCARD DNS"
   Wildcard DNS is supported for hosteddomains by placing a single period
   character before the domain name. For example, the hosted domain entry
   ".domain.com" will cause the Courier mail server to accept mail for
   "anything.domain.com".

   The Courier mail server will accept mail for
   <address@any.thing.domain.com> and attempt to deliver it to the local
   mailbox <address@any.thing.domain.com>, and if that fails then attempt
   to deliver the mail to the local mailbox <address@.thing.domain.com>,
   then finally <address@.domain.com>

       Note
       There is a period after the '@' character. If you want all mail for
       "any.thing.domain.com" to be delivered as though it were sent to
       "domain.com", you should define an alias for the domain, for
       example:

           domain.com
           .domain.com<TAB>domain.com

SEE ALSO

   esmtpd(8)[2].

AUTHOR

   Sam Varshavchik
       Author

NOTES

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

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



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