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264 lines
7.9 KiB
Plaintext
264 lines
7.9 KiB
Plaintext
# $OpenLDAP$
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# Copyright 2007 The OpenLDAP Foundation, All Rights Reserved.
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# COPYING RESTRICTIONS APPLY, see COPYRIGHT.
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H1: Backends
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H2: Berkley DB Backends
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H3: Overview
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The {{bdb}} backend to {{slapd}}(8) is the recommended primary backend for a
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normal {{slapd}} database. It uses the Oracle Berkeley DB ({{TERM:BDB}})
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package to store data. It makes extensive use of indexing and caching
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(see the {{SECT:Tuning}} section) to speed data access.
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{{hdb}} is a variant of the {{bdb}} backend that uses a hierarchical database
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layout which supports subtree renames. It is otherwise identical to the {{bdb}}
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behavior, and all the same configuration options apply.
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Note: An {{hdb}} database needs a large {{idlcachesize}} for good search performance,
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typically three times the {{cachesize}} (entry cache size) or larger.
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H3: back-bdb/back-hdb Configuration
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MORE LATER
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H3: Further Information
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{{slapd-bdb}}(5)
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H2: LDAP
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H3: Overview
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The LDAP backend to {{slapd}}(8) is not an actual database; instead it acts
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as a proxy to forward incoming requests to another LDAP server. While
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processing requests it will also chase referrals, so that referrals are fully
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processed instead of being returned to the {{slapd}} client.
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Sessions that explicitly {{Bind}} to the {{back-ldap}} database always create
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their own private connection to the remote LDAP server. Anonymous sessions
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will share a single anonymous connection to the remote server. For sessions
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bound through other mechanisms, all sessions with the same DN will share the
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same connection. This connection pooling strategy can enhance the proxy’s
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efficiency by reducing the overhead of repeatedly making/breaking multiple
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connections.
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The ldap database can also act as an information service, i.e. the identity
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of locally authenticated clients is asserted to the remote server, possibly
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in some modified form. For this purpose, the proxy binds to the remote server
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with some administrative identity, and, if required, authorizes the asserted
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identity.
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H3: back-ldap Configuration
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LATER
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H3: Further Information
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{{slapd-ldap}}(5)
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H2: LDIF
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H3: Overview
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The LDIF backend to {{slapd}}(8) is a basic storage backend that stores
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entries in text files in LDIF format, and exploits the filesystem to create
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the tree structure of the database. It is intended as a cheap, low performance
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easy to use backend, and it is exploited by higher-level internal structures
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to provide a permanent storage.
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When using Dynamic configuration over LDAP via {{cn=config}}, this is where all
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configuration is stored if {{slapd}}(8) if started with {{-F}}. See {{slapd-config}}(5)
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for more information
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H3: back-ldif Configuration
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LATER
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H3: Further Information
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{{slapd-ldif}}(5)
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H2: Metadirectory
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H3: Overview
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The meta backend to {{slapd}}(8) performs basic LDAP proxying with respect
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to a set of remote LDAP servers, called "targets". The information contained
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in these servers can be presented as belonging to a single Directory Information
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Tree ({{TERM:DIT}}).
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A basic knowledge of the functionality of the {{slapd-ldap}}(5) backend is
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recommended. This backend has been designed as an enhancement of the ldap
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backend. The two backends share many features (actually they also share portions
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of code). While the ldap backend is intended to proxy operations directed
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to a single server, the meta backend is mainly intended for proxying of
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multiple servers and possibly naming context masquerading.
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These features, although useful in many scenarios, may result in excessive
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overhead for some applications, so its use should be carefully considered.
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H3: back-meta Configuration
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LATER
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H3: Further Information
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{{slapd-meta}}(5)
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H2: Monitor
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H3: Overview
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The monitor backend to {{slapd}}(8) is not an actual database; if enabled,
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it is automatically generated and dynamically maintained by slapd with
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information about the running status of the daemon.
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To inspect all monitor information, issue a subtree search with base {{cn=Monitor}},
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requesting that attributes "+" and "*" are returned. The monitor backend produces
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mostly operational attributes, and LDAP only returns operational attributes
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that are explicitly requested. Requesting attribute "+" is an extension which
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requests all operational attributes.
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See the {{SECT:Monitoring}} section.
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H3: back-monitor Configuration
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LATER
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H3: Further Information
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{{slapd-monitor}}(5)
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H2: Null
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H3: Overview
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The Null backend to {{slapd}}(8) is surely the most useful part of slapd:
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- Searches return success but no entries.
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- Compares return compareFalse.
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- Updates return success (unless readonly is on) but do nothing.
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- Binds other than as the rootdn fail unless the database option "bind on" is given.
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- The slapadd(8) and slapcat(8) tools are equally exciting.
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Inspired by the {{F:/dev/null}} device.
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H3: back-null Configuration
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LATER
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H3: Further Information
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{{slapd-null}}(5)
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H2: Passwd
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H3: Overview
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The PASSWD backend to {{slapd}}(8) serves up the user account information
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listed in the system {{passwd}}(5) file.
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This backend is provided for demonstration purposes only. The DN of each entry
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is "uid=<username>,<suffix>".
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H3: back-passwd Configuration
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LATER
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H3: Further Information
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{{slapd-passwd}}(5)
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H2: Perl/Shell
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H3: Overview
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The Perl backend to {{slapd}}(8) works by embedding a {{perl}}(1) interpreter
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into {{slapd}}(8). Any perl database section of the configuration file
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{{slapd.conf}}(5) must then specify what Perl module to use. Slapd then creates
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a new Perl object that handles all the requests for that particular instance of the backend.
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The Shell backend to {{slapd}}(8) executes external programs to implement
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operations, and is designed to make it easy to tie an existing database to the
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slapd front-end. This backend is is primarily intended to be used in prototypes.
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H3: back-perl/back-shell Configuration
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LATER
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H3: Further Information
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{{slapd-shell}}(5) and {{slapd-perl}}(5)
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H2: Relay
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H3: Overview
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The primary purpose of this {{slapd}}(8) backend is to map a naming context
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defined in a database running in the same {{slapd}}(8) instance into a
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virtual naming context, with attributeType and objectClass manipulation, if
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required. It requires the rwm overlay.
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This backend and the above mentioned overlay are experimental.
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H3: back-relay Configuration
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LATER
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H3: Further Information
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{{slapd-relay}}(5)
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H2: SQL
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H3: Overview
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The primary purpose of this {{slapd}}(8) backend is to PRESENT information
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stored in some RDBMS as an LDAP subtree without any programming (some SQL and
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maybe stored procedures can’t be considered programming, anyway ;).
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That is, for example, when you (some ISP) have account information you use in
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an RDBMS, and want to use modern solutions that expect such information in LDAP
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(to authenticate users, make email lookups etc.). Or you want to synchronize or
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distribute information between different sites/applications that use RDBMSes
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and/or LDAP. Or whatever else...
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It is {{B:NOT}} designed as a general-purpose backend that uses RDBMS instead of
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BerkeleyDB (as the standard BDB backend does), though it can be used as such with
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several limitations. Please see {{SECT: LDAP vs RDBMS}} for discussion.
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The idea is to use some meta-information to translate LDAP queries to SQL queries,
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leaving relational schema untouched, so that old applications can continue using
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it without any modifications. This allows SQL and LDAP applications to interoperate
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without replication, and exchange data as needed.
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The SQL backend is designed to be tunable to virtually any relational schema without
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having to change source (through that meta-information mentioned). Also, it uses
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ODBC to connect to RDBMSes, and is highly configurable for SQL dialects RDBMSes
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may use, so it may be used for integration and distribution of data on different
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RDBMSes, OSes, hosts etc., in other words, in highly heterogeneous environment.
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This backend is experimental.
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H3: back-sql Configuration
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LATER
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H3: Further Information
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{{slapd-sql}}(5)
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