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Updated: Wednesday, February 9, 2022

slapd.backends (5oldap)


slapd.backends - alone LDAP daemon


Please see following description for synopsis


SLAPD.BACKENDS(5oldap)                                  SLAPD.BACKENDS(5oldap)

       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.

       bdb    This was the recommended primary backend through  OpenLDAP  2.3,
              but  it  has since been superseded by the mdb backend.  It takes
              care to configure it properly.  It uses the transactional  data-
              base  interface of the Oracle Berkeley DB (BDB) package to store

       config This 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 auto-
              matically,  so  it  is  always  present  even  if not explicitly
              defined in the slapd.conf(5) file.

       dnssrv This backend is experimental.  It serves up referrals based upon
              SRV resource records held in the Domain Name System.

       hdb    This was the recommended primary backend through OpenLDAP 2.4.40
              but it has since been superseded by the mdb backend.   It  takes
              care  to  configure  it  properly.   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

       ldap   This backend acts as a proxy to  forward  incoming  requests  to
              another LDAP server.

       ldif   This 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.

       mdb    This is the recommended primary backend, superseding hdb.   This
              backend  uses OpenLDAP's own MDB transactional database library.
              It is extremely compact and extremely efficient, delivering much
              higher  performance  than  the  Berkeley DB backends while using
              significantly less memory.  Also, unlike  Berkeley  DB,  MDB  is
              crash  proof,  and  requires  no  special tuning or maintenance.
              This backend also supports subtree renames.

       meta   This backend performs basic LDAP proxying with respect to a  set
              of  remote  LDAP servers. It is an enhancement of the ldap back-

              This backend provides information about the  running  status  of
              the  slapd daemon. Only a single instance of the monitor backend
              may be defined.

       ndb    This backend is experimental.  It uses the  transactional  data-
              base  interface of the MySQL Cluster Engine (NDB) to store data.
              Note that Oracle, which now owns MySQL,  has  withdrawn  support
              for  NDB  and  this backend is unlikely to be developed any fur-

       null   Operations in this backend succeed but do nothing.

       passwd This backend is provided for demonstration  purposes  only.   It
              serves  up  user  account  information from the system passwd(5)

       perl   This backend embeds a perl(1) interpreter into slapd.   It  runs
              Perl subroutines to implement LDAP operations.

       relay  This  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.

       shell  This backend executes external programs to implement LDAP opera-
              tions.  It is primarily intended to be used in prototypes.

       sql    This backend is experimental.  It services LDAP requests from an
              SQL database.

              default slapd configuration file

              default slapd configuration directory

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

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

       ldap(3), slapd-bdb(5), slapd-config(5), slapd-dnssrv(5),  slapd-hdb(5),
       slapd-ldap(5),  slapd-ldif(5), slapd-mdb(5), slapd-meta(5), slapd-moni-
       tor(5), slapd-ndb(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"

       OpenLDAP  Software  is developed and maintained by The OpenLDAP Project
       <http://www.openldap.org/>.  OpenLDAP Software is derived from the Uni-
       versity of Michigan LDAP 3.3 Release.

       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.BACKENDS(5oldap)