slapd-ldbm.5

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.TH SLAPD-LDBM 5 "RELEASEDATE" "OpenLDAP LDVERSION"
.\" Copyright 1998-2007 The OpenLDAP Foundation All Rights Reserved.
.\" Copying restrictions apply.  See COPYRIGHT/LICENSE.
.\" $OpenLDAP: pkg/ldap/doc/man/man5/slapd-ldbm.5,v 1.8.2.6 2007/01/02 21:43:45 kurt Exp $
.SH NAME
slapd-ldbm \- LDBM backend to slapd
.SH SYNOPSIS
ETCDIR/slapd.conf
.SH DESCRIPTION
The LDBM backend to
.BR slapd (8)
is an easy\-to\-configure but obsolete database backend.  It does not
offer the data durability features of the BDB and HDB backends and
hence is considered deprecated in favor of these robust backends.
LDBM uses lightweight non\-transactional data interfaces, such as those
provided by GDBM or Berkeley DB, to store data.  It makes extensive
use of indexing and caching to speed data access.
.SH CONFIGURATION
These
.B slapd.conf
options apply to the LDBM backend database.
That is, they must follow a "database ldbm" line and come before any
subsequent "backend" or "database" lines.
Other database options are described in the
.BR slapd.conf (5)
manual page.
.TP
.B cachesize <integer>
Specify the size in entries of the in-memory cache maintained 
by the LDBM backend database instance.
The default is 1000 entries.
.TP
.B dbcachesize <integer>
Specify the size in bytes of the in-memory cache associated with each
open index file.
If not supported by the underlying database method, this option is
ignored without comment.
The default is 100000 bytes.
.TP
.B dbnolocking
Specify that no database locking should be performed.  
Enabling this option may improve performance at the expense of data security.
Do NOT run any slap tools while slapd is running.
.TP
.B dbnosync
Specify that on-disk database contents should not be immediately
synchronized with in memory changes.
Enabling this option may improve performance at the expense of data
security.
.TP
.B dbsync <frequency> <maxdelays> <delayinterval>
Flush dirty database buffers to disk every
.B <seconds>
seconds.
Implies
.B dbnosync
(ie. individual updates are no longer written to disk).
It attempts to avoid syncs during periods of peak activity by waiting
.B <delayinterval>
seconds if the server is busy, repeating this delay up to
.B <maxdelays>
times before proceeding.  
It is an attempt to provide higher write performance with some amount
of data security.
Note that it may still be possible to get an inconsistent database if
the underlying engine fills its cache and writes out individual pages
and slapd crashes or is killed before the next sync.
.B <maxdelays>
and
.B <delayinterval>
are optional and default to
.B 12
and
.B 5
respectively, giving a total elapsed delay of 60 seconds before a sync
will occur.
.B <maxdelays>
may be zero, and
.B <delayinterval>
must be 1 or greater.
.TP
.B directory <directory>
Specify the directory where the LDBM files containing this database and
associated indexes live.
A separate directory must be specified for each database.
The default is
.BR LOCALSTATEDIR/openldap-data .
.TP
.B
index {<attrlist>|default} [pres,eq,approx,sub,<special>]
Specify the indexes to maintain for the given attribute (or
list of attributes).
Some attributes only support a subset of indexes.
If only an <attr> is given, the indices specified for \fBdefault\fR
are maintained.
Note that setting a default does not imply that all attributes will be
indexed. Also, for best performance, an
.B eq
index should always be configured for the
.B objectClass
attribute.

A number of special index parameters may be specified.
The index type
.B sub
can be decomposed into
.BR subinitial ,
.BR subany ,\ and
.B subfinal
indices.
The special type
.B notags
(or
.BR nolang )
may be specified to disallow use of this index by subtypes with tagging
options (such as language options).
The special type
.B nosubtypes
may be specified to disallow use of this index by named subtypes.
Note: changing index settings requires rebuilding indices, see
.BR slapindex (8).
.TP
.B mode <integer>
Specify the file protection mode that newly created database 
index files should have.
The default is 0600.
.SH ACCESS CONTROL
The 
.B ldbm
backend honors access control semantics as indicated in
.BR slapd.access (5).
.SH FILES
.TP
ETCDIR/slapd.conf
default slapd configuration file
.SH SEE ALSO
.BR slapd.conf (5),
.BR slapd (8),
.BR slapadd (8),
.BR slapcat (8),
.BR slapindex (8).