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Updated: Wednesday, February 9, 2022

slapd-ndb (5oldap)


slapd-ndb - MySQL NDB backend to slapd




SLAPD-NDB(5oldap)                                            SLAPD-NDB(5oldap)

       slapd-ndb - MySQL NDB backend to slapd


       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

       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 sep-
       arate 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 spec-
              ified 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  con-
              straint,  the  default  is  128 bytes.  Currently the maximum is

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

       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 defi-
              nition,  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

       The  ndb  backend  honors most access control semantics as indicated in

              default slapd configuration file

       See attributes(7) for descriptions of the following attributes:

       |ATTRIBUTE TYPE |       ATTRIBUTE VALUE         |
       |Availability   | service/network/ldap/openldap |
       |Stability      | Pass-through uncommitted      |

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

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

       Source  code  for open source software components in Oracle Solaris can
       be found at https://www.oracle.com/downloads/opensource/solaris-source-

       This     software     was    built    from    source    available    at
       https://github.com/oracle/solaris-userland.   The  original   community
       source  was downloaded from  ftp://ftp.openldap.org/pub/OpenLDAP/openl-

       Further information about this software can be found on the open source
       community website at http://www.openldap.org/.

OpenLDAP 2.4.57                   2021/01/18                 SLAPD-NDB(5oldap)