slapd.backends — backends for slapd, the stand-alone LDAP daemon
The slapd(8) daemon can use a variety of different backends for serving LDAP requests. Backends may be compiled statically into slapd, or when module support is enabled, they may be dynamically loaded. Multiple instances of a backend can be configured, to serve separate databases from the same slapd server.
Configuration options for each backend are documented separately in the corresponding slapd-<backend>(5) manual pages.
bdbThis was the recommended primary backend through
OpenLDAP 2.3, but it has since been superseded by the
hdb backend.
It takes care to configure it properly. It uses the
transactional database interface of the Oracle Berkeley
DB (BDB) package to store data.
configThis backend is used to manage the configuration of
slapd at run-time. Unlike other backends, only a single
instance of the config backend may be
defined. It also instantiates itself automatically, so
it is always present even if not explicitly defined in
the slapd.conf(5)
file.
dnssrvThis backend is experimental. It serves up referrals based upon SRV resource records held in the Domain Name System.
hdbThis is the recommended primary backend for a normal
slapd database. hdb is a variant of the
bdb backend
that uses a hierarchical database layout. This layout
stores entry DNs more efficiently than the bdb backend, using less
space and requiring less work to create, delete, and
rename entries. It is also one of the few backends to
support subtree renames.
This backend acts as a proxy to forward incoming requests to another LDAP server.
ldifThis database uses the filesystem to build the tree structure of the database, using plain ascii files to store data. Its usage should be limited to very simple databases, where performance is not a requirement. This backend also supports subtree renames.
metaThis backend performs basic LDAP proxying with respect to a set of remote LDAP servers. It is an enhancement of the ldap backend.
monitorThis backend provides information about the running
status of the slapd daemon. Only a single instance of
the monitor
backend may be defined.
ndbThis backend is experimental. It uses the transactional database interface of the MySQL Cluster Engine (NDB) to store data.
nullOperations in this backend succeed but do nothing.
passwdThis backend is provided for demonstration purposes only. It serves up user account information from the system passwd(5) file.
perlThis backend embeds a perl(1) interpreter into slapd. It runs Perl subroutines to implement LDAP operations.
relayThis backend is experimental. It redirects LDAP
operations to another database in the same server,
based on the naming context of the request. Its use
requires the rwm overlay (see
slapo-rwm(5) for
details) to rewrite the naming context of the request.
It is primarily intended to implement virtual views on
databases that actually store data.
shellThis backend executes external programs to implement LDAP operations. It is primarily intended to be used in prototypes.
sqlThis backend is experimental. It services LDAP requests from an SQL database.
default slapd configuration file
default slapd configuration directory
ldap(3), slapd-bdb(5), slapd-config(5), slapd-dnssrv(5), slapd-hdb(5), slapd-ldap(5), slapd-ldif(5), slapd-meta(5), slapd-monitor(5), slapd-null(5), slapd-passwd(5), slapd-perl(5), slapd-relay(5), slapd-shell(5), slapd-sql(5), slapd.conf(5), slapd.overlays(5), slapd(8). "OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)
OpenLDAP Software is developed and maintained by The OpenLDAP Project <http://www.openldap.org/>. OpenLDAP Software is derived from University of Michigan LDAP 3.3 Release.