slapd-ndb(5) — Linux manual page


SLAPD-NDB(5)                 File Formats Manual                SLAPD-NDB(5)

NAME         top

       slapd-ndb - MySQL NDB backend to slapd

SYNOPSIS         top


DESCRIPTION         top

       The ndb backend to slapd(8) uses the MySQL Cluster package to store
       data, through its NDB API.  It provides fault tolerance with extreme
       scalability, along with a degree of SQL compatibility.

       This backend is designed to store LDAP information using tables that
       are also visible from SQL. It uses a higher level SQL API for
       creating these tables, while using the low level NDB API for storing
       and retrieving the data within these tables. The NDB Cluster engine
       allows data to be partitioned across multiple data nodes, and this
       backend allows multiple slapd instances to operate against a given
       database concurrently.

       The general approach is to use distinct tables for each LDAP object
       class.  Entries comprised of multiple object classes will have their
       data spread across multiple tables. The data tables use a 64 bit
       entryID as their primary key. The DIT hierarchy is maintained in a
       separate table, which maps DNs to entryIDs.

       This backend is experimental. While intended to be a general-purpose
       backend, it is currently missing a number of common LDAP features.
       See the TODO file in the source directory for details.


       These slapd.conf options apply to the ndb backend database.  That is,
       they must follow a "database ndb" line and come before any subsequent
       "backend" or "database" lines.  Other database options are described
       in the slapd.conf(5) manual page.


       dbhost <hostname>
              The name or IP address of the host running the MySQL server.
              The default is "localhost". On Unix systems, the connection to
              a local server is made using a Unix Domain socket, whose path
              is specified using the dbsocket directive.

       dbuser <username>
              The MySQL login ID to use when connecting to the MySQL server.
              The chosen user must have sufficient privileges to manipulate
              the SQL tables in the target database.

       dbpasswd <password>
              The password for the dbuser.

       dbname <database name>
              The name of the MySQL database to use.

       dbport <port>
              The port number to use for the TCP connection to the MySQL

       dbsocket <path>
              The socket to be used for connecting to a local MySQL server.

       dbflag <integer>
              Client flags for the MySQL session. See the MySQL
              documentation for details.

       dbconnect <connectstring>
              The name or IP address of the host running the cluster
              manager. The default is "localhost".

       dbconnections <integer>
              The number of cluster connections to establish. Using up to 4
              may improve performance under heavier load. The default is 1.


       attrlen <attribute> <length>
              Specify the column length to use for a particular attribute.
              LDAP attributes are stored in individual columns of the SQL
              tables. The maximum column lengths for each column must be
              specified when creating these tables. If a length constraint
              was specified in the attribute's LDAP schema definition, that
              value will be used by default. If the schema didn't specify a
              constraint, the default is 128 bytes.  Currently the maximum
              is 1024.

       index <attr[,attr...]>
              Specify a list of attributes for which indexing should be
              maintained.  Currently there is no support for substring
              indexing; a single index structure provides presence,
              equality, and inequality indexing for the specified

       attrset <set> <attrs>
              Specify a list of attributes to be treated as an attribute
              set. This directive creates a table named set which will
              contain all of the listed attributes.  Ordinarily an attribute
              resides in a table named by an object class that uses the
              attribute. However, attributes are only allowed to appear in a
              single table.  For attributes that are derived from an
              inherited object class definition, the attribute will only be
              stored in the superior class's table.  Attribute sets should
              be defined for any attributes that are used in multiple
              unrelated object classes, i.e., classes that are not connected
              by a simple inheritance chain.

ACCESS CONTROL         top

       The ndb backend honors most access control semantics as indicated in

FILES         top

              default slapd configuration file

SEE ALSO         top

       slapd.conf(5), slapd-config(5), slapd(8), slapadd(8), slapcat(8),
       slapindex(8), MySQL Cluster documentation.

AUTHOR         top

       Howard Chu, with assistance from Johan Andersson et al @ MySQL.

COLOPHON         top

       This page is part of the OpenLDAP (an open source implementation of
       the Lightweight Directory Access 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 2020-11-01.  (At
       that time, the date of the most recent commit that was found in the
       repository was 2020-10-30.)  If you discover any rendering problems
       in this HTML version of the page, or you believe there is a better or
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       the original manual page), send a mail to

OpenLDAP LDVERSION               RELEASEDATE                    SLAPD-NDB(5)

Pages that refer to this page: slapd.backends(5)