makemap(8) — Linux manual page


MAKEMAP(8)             BSD System Manager's Manual            MAKEMAP(8)

NAME         top

     makemap — create database maps for smtpd

SYNOPSIS         top

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

DESCRIPTION         top

     Maps provide a generic interface for associating a 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 which is
     named 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

     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 a 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 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

           table domains db:/etc/mail/domains.db

           action "local" mbox

           match for domain <domains> action "local"


     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 a single virtual address, add “ user” to
     the users map.  To handle all mail destined to any user at, add “ 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 db:/etc/mail/vdomains.db
           table vusers db:/etc/mail/users.db

           action "local" mbox virtual <vusers>

           match for domain <vdomains> action "local"
           match for domain "" action "local"

FILES         top

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

EXIT STATUS         top

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

SEE ALSO         top

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

HISTORY         top

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

COLOPHON         top

     This page is part of the OpenSMTPD (a FREE implementation of the
     server-side SMTP protocol) project.  Information about the project
     can be found at  If you have a bug
     report for this manual page, see
     ⟨⟩.  This page was
     obtained from the project's upstream Git repository
     ⟨⟩ on 2023-06-23.  (At
     that time, the date of the most recent commit that was found in the
     repository was 2023-06-23.)  If you discover any rendering problems
     in this HTML version of the page, or you believe there is a better
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     of the original manual page), send a mail to

BSD                         February 13, 2021                        BSD