slapd.backends(5)

NAME

   slapd.backends - backends for slapd, the stand-alone LDAP daemon

DESCRIPTION

   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          but  it  has since been superseded by the hdb backend.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.

   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
          automatically,  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  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.

   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 will soon be 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
          backend.

   monitor
          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
          database  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
          further.

   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)
          file.

   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
          operations.  It is primarily intended to be used in prototypes.

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

FILES

   /etc/ldap/slapd.conf
          default slapd configuration file

   /etc/ldap/slapd.d
          default slapd configuration directory

SEE ALSO

   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-monitor(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" (http://www.OpenLDAP.org/doc/admin/)

ACKNOWLEDGEMENTS

   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.

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Free and Open Source Software