.TH SLAPD.OVERLAYS 5 "RELEASEDATE" "OpenLDAP LDVERSION"
.\" Copyright 2006-2019 The OpenLDAP Foundation All Rights Reserved.
.\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
.\" $OpenLDAP$
.SH NAME
slapd.overlays \- overlays for slapd, the stand-alone LDAP daemon
.SH DESCRIPTION
The
.BR slapd (8)
daemon can use a variety of different overlays to alter or extend
the normal behavior of a database backend.
Overlays may be compiled statically into slapd, or when module support
is enabled, they may be dynamically loaded. Most of the overlays
are only allowed to be configured on individual databases, but some
may also be configured globally.

Configuration options for each overlay are documented separately in the
corresponding
.BR slapo\-<overlay> (5)
manual pages.
.TP
.B accesslog
Access Logging.
This overlay can record accesses to a given backend database on another
database.
.TP
.B auditlog
Audit Logging.
This overlay records changes on a given backend database to an LDIF log
file.
By default it is not built.
.TP
.B chain
Chaining.
This overlay allows automatic referral chasing when a referral would
have been returned, either when configured by the server or when 
requested by the client.
.TP
.B collect
Collective Attributes.
This overlay implements RFC 3671 collective attributes; these
attributes share common values over all the members of the collection
as inherited from an ancestor entry.
.TP
.B constraint
Constraint.
This overlay enforces a regular expression constraint on all values
of specified attributes. It is used to enforce a more rigorous
syntax when the underlying attribute syntax is too general.
.TP
.B dds
Dynamic Directory Services.
This overlay supports dynamic objects, which have a limited life after
which they expire and are automatically deleted.
.TP
.B dyngroup
Dynamic Group.
This is a demo overlay which extends the Compare operation to detect
members of a dynamic group.
It has no effect on any other operations.
.TP
.B dynlist
Dynamic List.
This overlay allows expansion of dynamic groups and more.
.TP
.B memberof
MemberOf.
This overlay maintains automatic reverse group membership values,
typically stored in an attribute called memberOf.
.TP
.B pbind
Proxybind.
This overlay forwards simple bind requests on a local database to a
remote LDAP server.
.TP
.B pcache
Proxycache.
This overlay allows caching of LDAP search requests in a local database.
It is most often used with the
.BR slapd\-ldap (5)
or
.BR slapd\-meta (5)
backends.
.TP
.B ppolicy
Password Policy.
This overlay provides a variety of password control mechanisms,
e.g. password aging, password reuse and duplication control, mandatory
password resets, etc.
.TP
.B refint
Referential Integrity.
This overlay can be used with a backend database such as
.BR slapd\-bdb (5)
to maintain the cohesiveness of a schema which utilizes reference
attributes.
.TP
.B retcode
Return Code.
This overlay is useful to test the behavior of clients when
server-generated erroneous and/or unusual responses occur.
.TP
.B rwm
Rewrite/remap.
This overlay is experimental.
It performs basic DN/data rewrite and
objectClass/attributeType mapping.
.TP
.B sssvlv
Server Side Sorting and Virtual List Views.
This overlay implements the RFC2891 server-side sorting control and
virtual list view controls, and replaces the RFC2696 paged-results
implementation to ensure it works with the sorting technique.
.TP
.B syncprov
Syncrepl Provider.
This overlay implements the provider-side support for
.B syncrepl
replication, including persistent search functionality.
.TP
.B translucent
Translucent Proxy.
This overlay can be used with a backend database such as
.BR slapd\-bdb (5)
to create a "translucent proxy".
Content of entries retrieved from a remote LDAP server can be partially
overridden by the database.
.TP
.B unique
Attribute Uniqueness.
This overlay can be used with a backend database such as
.BR slapd\-bdb (5)
to enforce the uniqueness of some or all attributes within a subtree.
.TP
.B valsort
Value Sorting.
This overlay can be used to enforce a specific order for the values
of an attribute when it is returned in a search.
.SH FILES
.TP
ETCDIR/slapd.conf
default slapd configuration file
.TP
ETCDIR/slapd.d
default slapd configuration directory
.SH SEE ALSO
.BR ldap (3),
.BR slapo\-accesslog (5),
.BR slapo\-auditlog (5),
.BR slapo\-chain (5),
.BR slapo\-collect (5),
.BR slapo\-constraint (5),
.BR slapo\-dds (5),
.BR slapo\-dyngroup (5),
.BR slapo\-dynlist (5),
.BR slapo\-memberof (5),
.BR slapo\-pbind (5),
.BR slapo\-pcache (5),
.BR slapo\-ppolicy (5),
.BR slapo\-refint (5),
.BR slapo\-retcode (5),
.BR slapo\-rwm (5),
.BR slapo\-sssvlv (5),
.BR slapo\-syncprov (5),
.BR slapo\-translucent (5),
.BR slapo\-unique (5).
.BR slapo\-valsort (5).
.BR slapd\-config (5),
.BR slapd.conf (5),
.BR slapd.backends (5),
.BR slapd (8).
"OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)
.SH ACKNOWLEDGEMENTS
.so ../Project