SLAPD-NDB(5) File Formats Manual SLAPD-NDB(5)
NAME
slapd-ndb - MySQL NDB backend to slapd
SYNOPSIS
/etc/ldap/slapd.conf
DESCRIPTION
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 re-
trieving the data within these tables. The NDB Cluster engine allows
data to be partitioned across multiple data nodes, and this backend al-
lows multiple slapd instances to operate against a given database con-
currently.
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 en-
tryID as their primary key. The DIT hierarchy is maintained in a sepa-
rate 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.
CONFIGURATION
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.
DATA SOURCE CONFIGURATION
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 lo-
cal 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
server.
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.
SCHEMA CONFIGURATION
attrlen <attribute> <length>
Specify the column length to use for a particular attribute.
LDAP attributes are stored in individual columns of the SQL ta-
bles. The maximum column lengths for each column must be speci-
fied 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
1024.
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 at-
tributes that are used in multiple unrelated object classes,
i.e., classes that are not connected by a simple inheritance
chain.
ACCESS CONTROL
The ndb backend honors most access control semantics as indicated in
slapd.access(5).
FILES
/etc/ldap/slapd.conf
default slapd configuration file
SEE ALSO
slapd.conf(5), slapd-config(5), slapd(8), slapadd(8), slapcat(8),
slapindex(8), slapmodify(8), MySQL Cluster documentation.
AUTHOR
Howard Chu, with assistance from Johan Andersson et al @ MySQL.
OpenLDAP 2.5.13+dfsg-5 2022/07/14 SLAPD-NDB(5)
Generated by dwww version 1.15 on Wed Sep 3 05:00:24 CEST 2025.