makemap(8)


NAME

     makemap --- create database maps for smtpd

SYNOPSIS

     makemap [-U] [-d dbtype] [-o dbfile] [-t type] file

DESCRIPTION

     Maps provide a generic interface for associating textual key to a value.
     Such associations may be accessed through a plaintext file, database, or
     DNS.  The format of these file types is described below.  makemap itself
     creates the database maps used by keyed map lookups specified in
     smtpd.conf(5).

     makemap reads input from file and writes data to a file whose name is
     made by adding a ".db" suffix to file.  The current line can be extended
     over multiple lines using a backslash ('\').  Comments can be put
     anywhere in the file using a hash mark ('#'), and extend to the end of
     the current line.  Care should be taken when commenting out multi-line
     text: the comment is effective until the end of the entire block.  In all
     cases, makemap reads lines consisting of words separated by whitespace.
     The first word of a line is the database key; the remainder represents
     the mapped value.  The database key and value may optionally be separated
     by the colon character.

     The options are as follows:

     -d dbtype
         Specify the format of the database.  Available formats are hash
         and btree.  The default value is hash.

     -o dbfile
         Write the generated database to dbfile.

     -t type
         Specify the format of the resulting map file.  The default map
         format is suitable for storing simple, unstructured, key-to-value
         string associations.  However, if the mapped value has special
         meaning, as in the case of the virtual domains file, a suitable
         type must be provided.  The available output types are:

         aliases  The mapped value is a comma-separated list of mail
                  destinations.  This format can be used for building user
                  aliases and user mappings for virtual domain files.

         set      There is no mapped value -- a map of this type will only
                  allow for the lookup of keys.  This format can be used
                  for building primary domain maps.

     -U      Instead of generating a database map from text input, dump the
         contents of a database map as text with the key and value
         separated with a tab.

PRIMARY DOMAINS

     Primary domains can be kept in tables.  To create a primary domain table,
     add each primary domain on a single line by itself.

     In addition to adding an entry to the primary domain map, one must add a
     filter rule that accepts mail for the domain map, for example:

       table domains "/etc/domains"
       accept for domain <domains> deliver to mbox

VIRTUAL DOMAINS

     Virtual domains may also be kept in tables.  To create a virtual domain
     table, add each virtual domain on a single line by itself.

     Virtual domains expect a mapping of virtual users to real users in order
     to determine if a recipient is accepted or not.  The mapping format is an
     extension to aliases(5), which allows the use of "user@domain.tld" to
     accept user only on the specified domain, "user" to accept the user for
     any of the virtual domains, "@domain.tld" to provide a catch-all for the
     specified domain and "@" to provide a global catch-all for all domains.
     smtpd(8) will perform the lookups in that specific order.

     To create single virtual address, add "user@example.com user" to the
     users map.  To handle all mail destined to any user at example.com, add
     "@example.com user" to the virtual map.

     In addition to adding an entry to the virtual map, one must add a filter
     rule that accepts mail for virtual domains, for example:

       table vdomains "/etc/vdomains"
       table vusers "/etc/users"

       accept for domain <vdomains> virtual <vusers> deliver to mbox
       accept for domain example.org virtual <vusers> deliver to mbox

FILES

     /etc/aliases     List of user mail aliases.
     /etc/secrets     List of remote host credentials.

EXIT STATUS

     The makemap utility exits 0 on success, and >0 if an error occurs.

SEE ALSO

     aliases(5), smtpd.conf(5), table(5), newaliases(8), smtpd(8)

HISTORY

     The makemap command first appeared in OpenBSD 4.6 as a replacement for
     the equivalent command shipped with sendmail.





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