Provided by: slapd_2.6.9+dfsg-2ubuntu1_amd64 
NAME
slapd-config - configuration backend to slapd
SYNOPSIS
/etc/ldap/slapd.d
DESCRIPTION
The config backend manages all of the configuration information for the slapd(8) daemon. This
configuration information is also used by the SLAPD tools slapacl(8), slapadd(8), slapauth(8),
slapcat(8), slapdn(8), slapindex(8), slapmodify(8), and slaptest(8).
The config backend is backward compatible with the older slapd.conf(5) file but provides the ability to
change the configuration dynamically at runtime. If slapd is run with only a slapd.conf file dynamic
changes will be allowed but they will not persist across a server restart. Dynamic changes are only saved
when slapd is running from a slapd.d configuration directory.
Unlike other backends, there can only be one instance of the config backend, and most of its structure is
predefined. The root of the database is hardcoded to cn=config and this root entry contains global
settings for slapd. Multiple child entries underneath the root entry are used to carry various other
settings:
cn=Module
dynamically loaded modules
cn=Schema
schema definitions
olcBackend=xxx
backend-specific settings
olcDatabase=xxx
database-specific settings
The cn=Module entries will only appear in configurations where slapd was built with support for
dynamically loaded modules. There can be multiple entries, one for each configured module path. Within
each entry there will be values recorded for each module loaded on a given path. These entries have no
children.
The cn=Schema entry contains all of the hardcoded schema elements. The children of this entry contain
all user-defined schema elements. In schema that were loaded from include files, the child entry will be
named after the include file from which the schema was loaded. Typically the first child in this subtree
will be cn=core,cn=schema,cn=config.
olcBackend entries are for storing settings specific to a single backend type (and thus global to all
database instances of that type). At present, only back-mdb implements any options of this type, so this
setting is not needed for any other backends.
olcDatabase entries store settings specific to a single database instance. These entries may have
olcOverlay child entries corresponding to any overlays configured on the database. The olcDatabase and
olcOverlay entries may also have miscellaneous child entries for other settings as needed. There are two
special database entries that are predefined - one is an entry for the config database itself, and the
other is for the "frontend" database. Settings in the frontend database are inherited by the other
databases, unless they are explicitly overridden in a specific database.
The specific configuration options available are discussed below in the Global Configuration Options,
General Backend Options, and General Database Options. Options are set by defining LDAP attributes with
specific values. In general the names of the LDAP attributes are the same as the corresponding
slapd.conf keyword, with an "olc" prefix added on.
The parser for many of these attributes is the same as used for parsing the slapd.conf keywords. As such,
slapd.conf keywords that allow multiple items to be specified on one line, separated by whitespace, will
allow multiple items to be specified in one attribute value. However, when reading the attribute via
LDAP, the items will be returned as individual attribute values.
Backend-specific options are discussed in the slapd-<backend>(5) manual pages. Refer to the "OpenLDAP
Administrator's Guide" for more details on configuring slapd.
GLOBAL CONFIGURATION OPTIONS
Options described in this section apply to the server as a whole. Arguments that should be replaced by
actual text are shown in brackets <>.
These options may only be specified in the cn=config entry. This entry must have an objectClass of
olcGlobal.
olcAllows: <features>
Specify a set of features to allow (default none). bind_v2 allows acceptance of LDAPv2 bind
requests. Note that slapd(8) does not truly implement LDAPv2 (RFC 1777), now Historic (RFC 3494).
bind_anon_cred allows anonymous bind when credentials are not empty (e.g. when DN is empty).
bind_anon_dn allows unauthenticated (anonymous) bind when DN is not empty. update_anon allows
unauthenticated (anonymous) update operations to be processed (subject to access controls and
other administrative limits). proxy_authz_anon allows unauthenticated (anonymous) proxy
authorization control to be processed (subject to access controls, authorization and other
administrative limits).
olcArgsFile: <filename>
The (absolute) name of a file that will hold the slapd server's command line (program name and
options).
olcAttributeOptions: <option-name>...
Define tagging attribute options or option tag/range prefixes. Options must not end with `-',
prefixes must end with `-'. The `lang-' prefix is predefined. If you use the olcAttributeOptions
directive, `lang-' will no longer be defined and you must specify it explicitly if you want it
defined.
An attribute description with a tagging option is a subtype of that attribute description without
the option. Except for that, options defined this way have no special semantics. Prefixes
defined this way work like the `lang-' options: They define a prefix for tagging options starting
with the prefix. That is, if you define the prefix `x-foo-', you can use the option `x-foo-bar'.
Furthermore, in a search or compare, a prefix or range name (with a trailing `-') matches all
options starting with that name, as well as the option with the range name sans the trailing `-'.
That is, `x-foo-bar-' matches `x-foo-bar' and `x-foo-bar-baz'.
RFC 4520 reserves options beginning with `x-' for private experiments. Other options should be
registered with IANA, see RFC 4520 section 3.5. OpenLDAP also has the `binary' option built in,
but this is a transfer option, not a tagging option.
olcAuthIDRewrite: <rewrite-rule>
Used by the authentication framework to convert simple user names to an LDAP DN used for
authorization purposes. Its purpose is analogous to that of olcAuthzRegexp (see below). The
rewrite-rule is a set of rules analogous to those described in slapo-rwm(5) for data rewriting
(after stripping the rwm- prefix). olcAuthIDRewrite and olcAuthzRegexp should not be intermixed.
olcAuthzPolicy: <policy>
Used to specify which rules to use for Proxy Authorization. Proxy authorization allows a client
to authenticate to the server using one user's credentials, but specify a different identity to
use for authorization and access control purposes. It essentially allows user A to login as user
B, using user A's password. The none flag disables proxy authorization. This is the default
setting. The from flag will use rules in the authzFrom attribute of the authorization DN. The to
flag will use rules in the authzTo attribute of the authentication DN. The any flag, an alias for
the deprecated value of both, will allow any of the above, whatever succeeds first (checked in to,
from sequence. The all flag requires both authorizations to succeed.
The rules are mechanisms to specify which identities are allowed to perform proxy authorization.
The authzFrom attribute in an entry specifies which other users are allowed to proxy login to this
entry. The authzTo attribute in an entry specifies which other users this user can authorize as.
Use of authzTo rules can be easily abused if users are allowed to write arbitrary values to this
attribute. In general the authzTo attribute must be protected with ACLs such that only privileged
users can modify it. The value of authzFrom and authzTo describes an identity or a set of
identities; it can take five forms:
ldap:///<base>??[<scope>]?<filter>
dn[.<dnstyle>]:<pattern>
u[.<mech>[<realm>]]:<pattern>
group[/objectClass[/attributeType]]:<pattern>
<pattern>
<dnstyle>:={exact|onelevel|children|subtree|regex}
The first form is a valid LDAP URI where the <host>:<port>, the <attrs> and the <extensions>
portions must be absent, so that the search occurs locally on either authzFrom or authzTo.
The second form is a DN, with the optional style modifiers exact, onelevel, children, and subtree
for exact, onelevel, children and subtree matches, which cause <pattern> to be normalized
according to the DN normalization rules, or the special regex style, which causes the <pattern> to
be treated as a POSIX (''extended'') regular expression, as discussed in regex(7) and/or
re_format(7). A pattern of * means any non-anonymous DN.
The third form is a SASL id, with the optional fields <mech> and <realm> that allow to specify a
SASL mechanism, and eventually a SASL realm, for those mechanisms that support one. The need to
allow the specification of a mechanism is still debated, and users are strongly discouraged to
rely on this possibility.
The fourth form is a group specification. It consists of the keyword group, optionally followed
by the specification of the group objectClass and attributeType. The objectClass defaults to
groupOfNames. The attributeType defaults to member. The group with DN <pattern> is searched with
base scope, filtered on the specified objectClass. The values of the resulting attributeType are
searched for the asserted DN.
The fifth form is provided for backwards compatibility. If no identity type is provided, i.e.
only <pattern> is present, an exact DN is assumed; as a consequence, <pattern> is subjected to DN
normalization.
Since the interpretation of authzFrom and authzTo can impact security, users are strongly
encouraged to explicitly set the type of identity specification that is being used. A subset of
these rules can be used as third arg in the olcAuthzRegexp statement (see below); significantly,
the URI, provided it results in exactly one entry, and the dn.exact:<dn> forms.
olcAuthzRegexp: <match> <replace>
Used by the authentication framework to convert simple user names, such as provided by SASL
subsystem, or extracted from certificates in case of cert-based SASL EXTERNAL, or provided within
the RFC 4370 "proxied authorization" control, to an LDAP DN used for authorization purposes. Note
that the resulting DN need not refer to an existing entry to be considered valid. When an
authorization request is received from the SASL subsystem, the SASL USERNAME, REALM, and MECHANISM
are taken, when available, and combined into a name of the form
UID=<username>[[,CN=<realm>],CN=<mechanism>],CN=auth
This name is then compared against the match POSIX (''extended'') regular expression, and if the
match is successful, the name is replaced with the replace string. If there are wildcard strings
in the match regular expression that are enclosed in parenthesis, e.g.
UID=([^,]*),CN=.*
then the portion of the name that matched the wildcard will be stored in the numbered placeholder
variable $1. If there are other wildcard strings in parenthesis, the matching strings will be in
$2, $3, etc. up to $9. The placeholders can then be used in the replace string, e.g.
UID=$1,OU=Accounts,DC=example,DC=com
The replaced name can be either a DN, i.e. a string prefixed by "dn:", or an LDAP URI. If the
latter, the server will use the URI to search its own database(s) and, if the search returns
exactly one entry, the name is replaced by the DN of that entry. The LDAP URI must have no
hostport, attrs, or extensions components, but the filter is mandatory, e.g.
ldap:///OU=Accounts,DC=example,DC=com??one?(UID=$1)
The protocol portion of the URI must be strictly ldap. Note that this search is subject to access
controls. Specifically, the authentication identity must have "auth" access in the subject.
Multiple olcAuthzRegexp values can be specified to allow for multiple matching and replacement
patterns. The matching patterns are checked in the order they appear in the attribute, stopping at
the first successful match.
olcConcurrency: <integer>
Specify a desired level of concurrency. Provided to the underlying thread system as a hint. The
default is not to provide any hint. This setting is only meaningful on some platforms where there
is not a one to one correspondence between user threads and kernel threads.
olcConnMaxPending: <integer>
Specify the maximum number of pending requests for an anonymous session. If requests are
submitted faster than the server can process them, they will be queued up to this limit. If the
limit is exceeded, the session is closed. The default is 100.
olcConnMaxPendingAuth: <integer>
Specify the maximum number of pending requests for an authenticated session. The default is 1000.
olcDisallows: <features>
Specify a set of features to disallow (default none). bind_anon disables acceptance of anonymous
bind requests. Note that this setting does not prohibit anonymous directory access (See "require
authc"). bind_simple disables simple (bind) authentication. tls_2_anon disables forcing session
to anonymous status (see also tls_authc) upon StartTLS operation receipt. tls_authc disallows the
StartTLS operation if authenticated (see also tls_2_anon). proxy_authz_non_critical disables
acceptance of the proxied authorization control (RFC4370) with criticality set to FALSE.
dontusecopy_non_critical disables acceptance of the dontUseCopy control (a work in progress) with
criticality set to FALSE.
olcGentleHUP: { TRUE | FALSE }
A SIGHUP signal will only cause a 'gentle' shutdown-attempt: Slapd will stop listening for new
connections, but will not close the connections to the current clients. Future write operations
return unwilling-to-perform, though. Slapd terminates when all clients have closed their
connections (if they ever do), or - as before - if it receives a SIGTERM signal. This can be
useful if you wish to terminate the server and start a new slapd server with another database,
without disrupting the currently active clients. The default is FALSE. You may wish to use
olcIdleTimeout along with this option.
olcIdleTimeout: <integer>
Specify the number of seconds to wait before forcibly closing an idle client connection. A
setting of 0 disables this feature. The default is 0. You may also want to set the
olcWriteTimeout option.
olcIndexHash64: { TRUE | FALSE }
Use a 64 bit hash for indexing. The default is to use 32 bit hashes. These hashes are used for
equality and substring indexing. The 64 bit version may be needed to avoid index collisions when
the number of indexed values exceeds ~64 million. (Note that substring indexing generates multiple
index values per actual attribute value.) Indices generated with 32 bit hashes are incompatible
with the 64 bit version, and vice versa. Any existing databases must be fully reloaded when
changing this setting. This directive is only supported on 64 bit CPUs.
olcIndexIntLen: <integer>
Specify the key length for ordered integer indices. The most significant bytes of the binary
integer will be used for index keys. The default value is 4, which provides exact indexing for 31
bit values. A floating point representation is used to index too large values.
olcIndexSubstrIfMaxlen: <integer>
Specify the maximum length for subinitial and subfinal indices. Only this many characters of an
attribute value will be processed by the indexing functions; any excess characters are ignored.
The default is 4.
olcIndexSubstrIfMinlen: <integer>
Specify the minimum length for subinitial and subfinal indices. An attribute value must have at
least this many characters in order to be processed by the indexing functions. The default is 2.
olcIndexSubstrAnyLen: <integer>
Specify the length used for subany indices. An attribute value must have at least this many
characters in order to be processed. Attribute values longer than this length will be processed in
segments of this length. The default is 4. The subany index will also be used in subinitial and
subfinal index lookups when the filter string is longer than the olcIndexSubstrIfMaxlen value.
olcIndexSubstrAnyStep: <integer>
Specify the steps used in subany index lookups. This value sets the offset for the segments of a
filter string that are processed for a subany index lookup. The default is 2. For example, with
the default values, a search using this filter "cn=*abcdefgh*" would generate index lookups for
"abcd", "cdef", and "efgh".
Note: Indexing support depends on the particular backend in use. Also, changing these settings will
generally require deleting any indices that depend on these parameters and recreating them with
slapindex(8).
olcListenerThreads: <integer>
Specify the number of threads to use for the connection manager. The default is 1 and this is
typically adequate for up to 16 CPU cores. The value should be set to a power of 2.
olcLocalSSF: <SSF>
Specifies the Security Strength Factor (SSF) to be given local LDAP sessions, such as those to the
ldapi:// listener. For a description of SSF values, see olcSaslSecProps's minssf option
description. The default is 71.
olcLogFile: <filename>
Specify a file for recording slapd debug messages. These messages are unrelated to messages
exposed by the olcLogLevel configuration parameter. This setting only affects the slapd daemon and
has no effect on the command line tools. By default these messages only go to stderr and are not
recorded anywhere else. Specifying a logfile copies messages to both stderr and the logfile.
olcLogFileFormat: debug | syslog-utc | syslog-localtime
Specify the prefix format for messages written to the logfile. The debug format is the normal
format used for slapd debug messages, with a timestamp in hexadecimal, followed by a thread ID.
The other options are to use syslog(3) style prefixes, with timestamps either in UTC or in the
local timezone. The default is debug format.
olcLogFileOnly: TRUE | FALSE
Specify that debug messages should only go to the configured logfile, and not to stderr.
olcLogFileRotate: <max> <Mbytes> <hours>
Specify automatic rotation for the configured logfile as the maximum number of old logfiles to
retain, a maximum size in megabytes to allow a logfile to grow before rotation, and a maximum age
in hours for a logfile to be used before rotation. The maximum number must be in the range 1-99.
Setting Mbytes or hours to zero disables the size or age check, respectively. At least one of
Mbytes or hours must be non-zero. By default no automatic rotation will be performed.
olcLogLevel: <integer> [...]
Specify the level at which debugging statements and operation statistics should be syslogged
(currently logged to the syslogd(8) LOG_LOCAL4 facility). They must be considered subsystems
rather than increasingly verbose log levels. Some messages with higher priority are logged
regardless of the configured loglevel as soon as any logging is configured. Log levels are
additive, and available levels are:
1 (0x1 trace) trace function calls
2 (0x2 packets) debug packet handling
4 (0x4 args) heavy trace debugging (function args)
8 (0x8 conns) connection management
16 (0x10 BER) print out packets sent and received
32 (0x20 filter) search filter processing
64 (0x40 config) configuration file processing
128 (0x80 ACL) access control list processing
256 (0x100 stats) connections, LDAP operations, results (recommended)
512 (0x200 stats2) stats2 log entries sent
1024 (0x400 shell) print communication with shell backends
2048 (0x800 parse) entry parsing
16384 (0x4000 sync) LDAPSync replication
32768 (0x8000 none) only messages that get logged whatever log level is set
The desired log level can be input as a single integer that combines the (ORed) desired levels,
both in decimal or in hexadecimal notation, as a list of integers (that are ORed internally), or
as a list of the names that are shown between parenthesis, such that
olcLogLevel: 129
olcLogLevel: 0x81
olcLogLevel: 128 1
olcLogLevel: 0x80 0x1
olcLogLevel: acl trace
are equivalent. The keyword any can be used as a shortcut to enable logging at all levels
(equivalent to -1). The keyword none, or the equivalent integer representation, causes those
messages that are logged regardless of the configured olcLogLevel to be logged. In fact, if no
olcLogLevel (or a 0 level) is defined, no logging occurs, so at least the none level is required
to have high priority messages logged.
Note that the packets, BER, and parse levels are only available as debug output on stderr, and are
not sent to syslog.
This setting defaults to stats. This level should usually also be included when using other
loglevels, to help analyze the logs.
olcMaxFilterDepth: <integer>
Specify the maximum depth of nested filters in search requests. The default is 1000.
olcPasswordCryptSaltFormat: <format>
Specify the format of the salt passed to crypt(3) when generating {CRYPT} passwords (see
olcPasswordHash) during processing of LDAP Password Modify Extended Operations (RFC 3062).
This string needs to be in sprintf(3) format and may include one (and only one) %s conversion.
This conversion will be substituted with a string of random characters from [A-Za-z0-9./]. For
example, "%.2s" provides a two character salt and "$1$%.8s" tells some versions of crypt(3) to use
an MD5 algorithm and provides 8 random characters of salt. The default is "%s", which provides 31
characters of salt.
olcPidFile: <filename>
The (absolute) name of a file that will hold the slapd server's process ID (see getpid(2)).
olcPluginLogFile: <filename>
The ( absolute ) name of a file that will contain log messages from SLAPI plugins. See
slapd.plugin(5) for details.
olcReferral: <url>
Specify the referral to pass back when slapd(8) cannot find a local database to handle a request.
If multiple values are specified, each url is provided.
olcReverseLookup: TRUE | FALSE
Enable/disable client name unverified reverse lookup (default is FALSE if compiled with
--enable-rlookups).
olcRootDSE: <file>
Specify the name of an LDIF(5) file containing user defined attributes for the root DSE. These
attributes are returned in addition to the attributes normally produced by slapd.
The root DSE is an entry with information about the server and its capabilities, in operational
attributes. It has the empty DN, and can be read with e.g.:
ldapsearch -x -b "" -s base "+"
See RFC 4512 section 5.1 for details.
olcSaslAuxprops: <plugin> [...]
Specify which auxprop plugins to use for authentication lookups. The default is empty, which just
uses slapd's internal support. Usually no other auxprop plugins are needed.
olcSaslAuxpropsDontUseCopy: <attr> [...]
Specify which attribute(s) should be subject to the don't use copy control. This is necessary for
some SASL mechanisms such as OTP to work in a replicated environment. The attribute
"cmusaslsecretOTP" is the default value.
olcSaslAuxpropsDontUseCopyIgnore TRUE | FALSE
Used to disable replication of the attribute(s) defined by olcSaslAuxpropsDontUseCopy and instead
use a local value for the attribute. This allows the SASL mechanism to continue to work if the
provider is offline. This can cause replication inconsistency. Defaults to FALSE.
olcSaslHost: <fqdn>
Used to specify the fully qualified domain name used for SASL processing.
olcSaslRealm: <realm>
Specify SASL realm. Default is empty.
olcSaslCbinding: none | tls-unique | tls-endpoint
Specify the channel-binding type, see also LDAP_OPT_X_SASL_CBINDING. Default is none.
olcSaslSecProps: <properties>
Used to specify Cyrus SASL security properties. The none flag (without any other properties)
causes the flag properties default, "noanonymous,noplain", to be cleared. The noplain flag
disables mechanisms susceptible to simple passive attacks. The noactive flag disables mechanisms
susceptible to active attacks. The nodict flag disables mechanisms susceptible to passive
dictionary attacks. The noanonymous flag disables mechanisms which support anonymous login. The
forwardsec flag require forward secrecy between sessions. The passcred require mechanisms which
pass client credentials (and allow mechanisms which can pass credentials to do so). The
minssf=<factor> property specifies the minimum acceptable security strength factor as an integer
approximate to effective key length used for encryption. 0 (zero) implies no protection, 1
implies integrity protection only, 128 allows RC4, Blowfish and other similar ciphers, 256 will
require modern ciphers. The default is 0. The maxssf=<factor> property specifies the maximum
acceptable security strength factor as an integer (see minssf description). The default is
INT_MAX. The maxbufsize=<size> property specifies the maximum security layer receive buffer size
allowed. 0 disables security layers. The default is 65536.
olcServerID: <integer> [<URL>]
Specify an integer ID from 0 to 4095 for this server. The ID may also be specified as a
hexadecimal ID by prefixing the value with "0x". Non-zero IDs are required when using multi-
provider replication and each provider must have a unique non-zero ID. Note that this requirement
also applies to separate providers contributing to a glued set of databases. If the URL is
provided, this directive may be specified multiple times, providing a complete list of
participating servers and their IDs. The fully qualified hostname of each server should be used in
the supplied URLs. The IDs are used in the "replica id" field of all CSNs generated by the
specified server. The default value is zero, which is only valid for single provider replication.
Example:
olcServerID: 1 ldap://ldap1.example.com
olcServerID: 2 ldap://ldap2.example.com
olcSockbufMaxIncoming: <integer>
Specify the maximum incoming LDAP PDU size for anonymous sessions. The default is 262143.
olcSockbufMaxIncomingAuth: <integer>
Specify the maximum incoming LDAP PDU size for authenticated sessions. The default is 4194303.
olcTCPBuffer [listener=<URL>] [{read|write}=]<size>
Specify the size of the TCP buffer. A global value for both read and write TCP buffers related to
any listener is defined, unless the listener is explicitly specified, or either the read or write
qualifiers are used. See tcp(7) for details. Note that some OS-es implement automatic TCP buffer
tuning.
olcThreads: <integer>
Specify the maximum size of the primary thread pool. The default is 16; the minimum value is 2.
olcThreadQueues: <integer>
Specify the number of work queues to use for the primary thread pool. The default is 1 and this
is typically adequate for up to 8 CPU cores. The value should not exceed the number of CPUs in
the system.
olcToolThreads: <integer>
Specify the maximum number of threads to use in tool mode. This should not be greater than the
number of CPUs in the system. The default is 1.
olcWriteTimeout: <integer>
Specify the number of seconds to wait before forcibly closing a connection with an outstanding
write. This allows recovery from various network hang conditions. A setting of 0 disables this
feature. The default is 0.
TLS OPTIONS
If slapd is built with support for Transport Layer Security, there are more options you can specify.
olcTLSCipherSuite: <cipher-suite-spec>
Permits configuring what ciphers will be accepted and the preference order. <cipher-suite-spec>
should be a cipher specification for the TLS library in use (OpenSSL or GnuTLS). Example:
OpenSSL:
olcTLSCipherSuite: HIGH:MEDIUM:+SSLv2
GnuTLS:
olcTLSCiphersuite: SECURE256:!AES-128-CBC
To check what ciphers a given spec selects in OpenSSL, use:
openssl ciphers -v <cipher-suite-spec>
With GnuTLS the available specs can be found in the manual page of gnutls-cli(1) (see the
description of the option --priority).
In older versions of GnuTLS, where gnutls-cli does not support the option --priority, you can
obtain the — more limited — list of ciphers by calling:
gnutls-cli -l
olcTLSCACertificateFile: <filename>
Specifies the file that contains certificates for all of the Certificate Authorities that slapd
will recognize. The certificate for the CA that signed the server certificate must be included
among these certificates. If the signing CA was not a top-level (root) CA, certificates for the
entire sequence of CA's from the signing CA to the top-level CA should be present. Multiple
certificates are simply appended to the file; the order is not significant.
olcTLSCACertificatePath: <path>
Specifies the path of directories that contain Certificate Authority certificates in separate
individual files. Usually only one of this or the olcTLSCACertificateFile is defined. If both are
specified, both locations will be used. Multiple directories may be specified, separated by a
semi-colon.
olcTLSCertificateFile: <filename>
Specifies the file that contains the slapd server certificate.
When using OpenSSL that file may also contain any number of intermediate certificates after the
server certificate.
olcTLSCertificateKeyFile: <filename>
Specifies the file that contains the slapd server private key that matches the certificate stored
in the olcTLSCertificateFile file. If the private key is protected with a password, the password
must be manually typed in when slapd starts. Usually the private key is not protected with a
password, to allow slapd to start without manual intervention, so it is of critical importance
that the file is protected carefully.
olcTLSDHParamFile: <filename>
This directive specifies the file that contains parameters for Diffie-Hellman ephemeral key
exchange. This is required in order to use a DSA certificate on the server, or an RSA certificate
missing the "key encipherment" key usage. Note that setting this option may also enable Anonymous
Diffie-Hellman key exchanges in certain non-default cipher suites. Anonymous key exchanges should
generally be avoided since they provide no actual client or server authentication and provide no
protection against man-in-the-middle attacks. You should append "!ADH" to your cipher suites to
ensure that these suites are not used.
olcTLSECName: <name>
Specify the name of the curve(s) to use for Elliptic curve Diffie-Hellman ephemeral key exchange.
This option is only used for OpenSSL. This option is not used with GnuTLS; the curves may be
chosen in the GnuTLS ciphersuite specification.
olcTLSProtocolMin: <major>[.<minor>]
Specifies minimum SSL/TLS protocol version that will be negotiated. If the server doesn't support
at least that version, the SSL handshake will fail. To require TLS 1.x or higher, set this option
to 3.(x+1), e.g.,
olcTLSProtocolMin: 3.2
would require TLS 1.1. Specifying a minimum that is higher than that supported by the OpenLDAP
implementation will result in it requiring the highest level that it does support. This directive
is ignored with GnuTLS.
olcTLSRandFile: <filename>
Specifies the file to obtain random bits from when /dev/[u]random is not available. Generally set
to the name of the EGD/PRNGD socket. The environment variable RANDFILE can also be used to
specify the filename. This directive is ignored with GnuTLS.
olcTLSVerifyClient: <level>
Specifies what checks to perform on client certificates in an incoming TLS session, if any. The
<level> can be specified as one of the following keywords:
never This is the default. slapd will not ask the client for a certificate.
allow The client certificate is requested. If no certificate is provided, the session proceeds
normally. If a bad certificate is provided, it will be ignored and the session proceeds
normally.
try The client certificate is requested. If no certificate is provided, the session proceeds
normally. If a bad certificate is provided, the session is immediately terminated.
demand | hard | true
These keywords are all equivalent, for compatibility reasons. The client certificate is
requested. If no certificate is provided, or a bad certificate is provided, the session is
immediately terminated.
Note that a valid client certificate is required in order to use the SASL EXTERNAL
authentication mechanism with a TLS session. As such, a non-default olcTLSVerifyClient
setting must be chosen to enable SASL EXTERNAL authentication.
olcTLSCRLCheck: <level>
Specifies if the Certificate Revocation List (CRL) of the CA should be used to verify if the
client certificates have not been revoked. This requires olcTLSCACertificatePath parameter to be
set. This parameter is ignored with GnuTLS. <level> can be specified as one of the following
keywords:
none No CRL checks are performed
peer Check the CRL of the peer certificate
all Check the CRL for a whole certificate chain
olcTLSCRLFile: <filename>
Specifies a file containing a Certificate Revocation List to be used for verifying that
certificates have not been revoked. This parameter is only valid when using GnuTLS.
DYNAMIC MODULE OPTIONS
If slapd is compiled with --enable-modules then the module-related entries will be available. These
entries are named cn=module{x},cn=config and must have the olcModuleList objectClass. One entry should be
created per olcModulePath. Normally the config engine generates the "{x}" index in the RDN
automatically, so it can be omitted when initially loading these entries.
olcModuleLoad: <filename> [<arguments>...]
Specify the name of a dynamically loadable module to load and any additional arguments if
supported by the module. The filename may be an absolute path name or a simple filename. Non-
absolute names are searched for in the directories specified by the olcModulePath option.
olcModulePath: <pathspec>
Specify a list of directories to search for loadable modules. Typically the path is colon-
separated but this depends on the operating system. The default is /usr/lib/ldap, which is where
the standard OpenLDAP install will place its modules.
SCHEMA OPTIONS
Schema definitions are created as entries in the cn=schema,cn=config subtree. These entries must have the
olcSchemaConfig objectClass. As noted above, the actual cn=schema,cn=config entry is predefined and any
values specified for it are ignored.
olcAttributetypes: ( <oid> [NAME <name>] [DESC <description>] [OBSOLETE] [SUP <oid>] [EQUALITY <oid>]
[ORDERING <oid>] [SUBSTR <oid>] [SYNTAX <oidlen>] [SINGLE-VALUE] [COLLECTIVE]
[NO-USER-MODIFICATION] [USAGE <attributeUsage>] )
Specify an attribute type using the LDAPv3 syntax defined in RFC 4512. The slapd parser extends
the RFC 4512 definition by allowing string forms as well as numeric OIDs to be used for the
attribute OID and attribute syntax OID. (See the olcObjectIdentifier description.)
olcDitContentRules: ( <oid> [NAME <name>] [DESC <description>] [OBSOLETE] [AUX <oids>] [MUST <oids>]
[MAY <oids>] [NOT <oids>] )
Specify an DIT Content Rule using the LDAPv3 syntax defined in RFC 4512. The slapd parser extends
the RFC 4512 definition by allowing string forms as well as numeric OIDs to be used for the
attribute OID and attribute syntax OID. (See the olcObjectIdentifier description.)
olcLdapSyntaxes ( <oid> [DESC <description>] [X-SUBST <substitute-syntax>] )
Specify an LDAP syntax using the LDAPv3 syntax defined in RFC 4512. The slapd parser extends the
RFC 4512 definition by allowing string forms as well as numeric OIDs to be used for the syntax
OID. (See the objectidentifier description.) The slapd parser also honors the X-SUBST extension
(an OpenLDAP-specific extension), which allows one to use the olcLdapSyntaxes attribute to define
a non-implemented syntax along with another syntax, the extension value substitute-syntax, as its
temporary replacement. The substitute-syntax must be defined. This allows one to define
attribute types that make use of non-implemented syntaxes using the correct syntax OID. Unless
X-SUBST is used, this configuration statement would result in an error, since no handlers would be
associated to the resulting syntax structure.
olcObjectClasses: ( <oid> [NAME <name>] [DESC <description>] [OBSOLETE] [SUP <oids>] [{ ABSTRACT |
STRUCTURAL | AUXILIARY }] [MUST <oids>] [MAY <oids>] )
Specify an objectclass using the LDAPv3 syntax defined in RFC 4512. The slapd parser extends the
RFC 4512 definition by allowing string forms as well as numeric OIDs to be used for the object
class OID. (See the olcObjectIdentifier description.) Object classes are "STRUCTURAL" by
default.
olcObjectIdentifier: <name> { <oid> | <name>[:<suffix>] }
Define a string name that equates to the given OID. The string can be used in place of the numeric
OID in objectclass and attribute definitions. The name can also be used with a suffix of the form
":xx" in which case the value "oid.xx" will be used.
GENERAL BACKEND OPTIONS
Options in these entries only apply to the configuration of a single type of backend. All backends may
support this class of options, but currently only back-mdb does. The entry must be named
olcBackend=<databasetype>,cn=config and must have the olcBackendConfig objectClass. <databasetype>
should be one of asyncmeta, config, dnssrv, ldap, ldif, mdb, meta, monitor, null, passwd, perl, relay,
sock, sql, or wt. At present, only back-mdb implements any options of this type, so this entry should
not be used for any other backends.
DATABASE OPTIONS
Database options are set in entries named olcDatabase={x}<databasetype>,cn=config and must have the
olcDatabaseConfig objectClass. Normally the config engine generates the "{x}" index in the RDN
automatically, so it can be omitted when initially loading these entries.
The special frontend database is always numbered "{-1}" and the config database is always numbered "{0}".
GLOBAL DATABASE OPTIONS
Options in this section may be set in the special "frontend" database and inherited in all the other
databases. These options may be altered by further settings in each specific database. The frontend entry
must be named olcDatabase=frontend,cn=config and must have the olcFrontendConfig objectClass.
olcAccess: to <what> [ by <who> <access> <control> ]+
Grant access (specified by <access>) to a set of entries and/or attributes (specified by <what>)
by one or more requestors (specified by <who>). If no access controls are present, the default
policy allows anyone and everyone to read anything but restricts updates to rootdn. (e.g.,
"olcAccess: to * by * read"). See slapd.access(5) and the "OpenLDAP Administrator's Guide" for
details.
Access controls set in the frontend are appended to any access controls set on the specific
databases. The rootdn of a database can always read and write EVERYTHING in that database.
Extra special care must be taken with the access controls on the config database. Unlike other
databases, the default policy for the config database is to only allow access to the rootdn.
Regular users should not have read access, and write access should be granted very carefully to
privileged administrators.
olcDefaultSearchBase: <dn>
Specify a default search base to use when client submits a non-base search request with an empty
base DN. Base scoped search requests with an empty base DN are not affected. This setting is
only allowed in the frontend entry.
olcExtraAttrs: <attr>
Lists what attributes need to be added to search requests. Local storage backends return the
entire entry to the frontend. The frontend takes care of only returning the requested attributes
that are allowed by ACLs. However, features like access checking and so may need specific
attributes that are not automatically returned by remote storage backends, like proxy backends and
so on. <attr> is an attribute that is needed for internal purposes and thus always needs to be
collected, even when not explicitly requested by clients. This attribute is multi-valued.
olcPasswordHash: <hash> [<hash>...]
This option configures one or more hashes to be used in generation of user passwords stored in the
userPassword attribute during processing of LDAP Password Modify Extended Operations (RFC 3062).
The <hash> must be one of {SSHA}, {SHA}, {SMD5}, {MD5}, {CRYPT}, and {CLEARTEXT}. The default is
{SSHA}.
{SHA} and {SSHA} use the SHA-1 algorithm (FIPS 160-1), the latter with a seed.
{MD5} and {SMD5} use the MD5 algorithm (RFC 1321), the latter with a seed.
{CRYPT} uses the crypt(3).
{CLEARTEXT} indicates that the new password should be added to userPassword as clear text.
Note that this option does not alter the normal user applications handling of userPassword during
LDAP Add, Modify, or other LDAP operations. This setting is only allowed in the frontend entry.
olcReadOnly: TRUE | FALSE
This option puts the database into "read-only" mode. Any attempts to modify the database will
return an "unwilling to perform" error. By default, olcReadOnly is FALSE. Note that when this
option is set TRUE on the frontend, it cannot be reset without restarting the server, since
further writes to the config database will be rejected.
olcRequires: <conditions>
Specify a set of conditions to require (default none). The directive may be specified globally
and/or per-database; databases inherit global conditions, so per-database specifications are
additive. bind requires bind operation prior to directory operations. LDAPv3 requires session to
be using LDAP version 3. authc requires authentication prior to directory operations. SASL
requires SASL authentication prior to directory operations. strong requires strong authentication
prior to directory operations. The strong keyword allows protected "simple" authentication as
well as SASL authentication. none may be used to require no conditions (useful to clear out
globally set conditions within a particular database); it must occur first in the list of
conditions.
olcRestrict: <oplist>
Specify a list of operations that are restricted. Restrictions on a specific database override
any frontend setting. Operations can be any of add, bind, compare, delete, extended[=<OID>],
modify, rename, search, or the special pseudo-operations read and write, which respectively
summarize read and write operations. The use of restrict write is equivalent to olcReadOnly: TRUE
(see above). The extended keyword allows one to indicate the OID of the specific operation to be
restricted.
olcSchemaDN: <dn>
Specify the distinguished name for the subschema subentry that controls the entries on this
server. The default is "cn=Subschema".
olcSecurity: <factors>
Specify a set of security strength factors (separated by white space) to require (see
olcSaslSecprops's minssf option for a description of security strength factors). The directive
may be specified globally and/or per-database. ssf=<n> specifies the overall security strength
factor. transport=<n> specifies the transport security strength factor. tls=<n> specifies the
TLS security strength factor. sasl=<n> specifies the SASL security strength factor.
update_ssf=<n> specifies the overall security strength factor to require for directory updates.
update_transport=<n> specifies the transport security strength factor to require for directory
updates. update_tls=<n> specifies the TLS security strength factor to require for directory
updates. update_sasl=<n> specifies the SASL security strength factor to require for directory
updates. simple_bind=<n> specifies the security strength factor required for simple
username/password authentication. Note that the transport factor is measure of security provided
by the underlying transport, e.g. ldapi:// (and eventually IPSEC). It is not normally used.
olcSizeLimit: {<integer>|unlimited}
olcSizeLimit: size[.{soft|hard}]=<integer> [...]
Specify the maximum number of entries to return from a search operation. The default size limit
is 500. Use unlimited to specify no limits. The second format allows a fine grain setting of the
size limits. If no special qualifiers are specified, both soft and hard limits are set. Extra
args can be added in the same value. Additional qualifiers are available; see olcLimits for an
explanation of all of the different flags.
olcSortVals: <attr> [...]
Specify a list of multi-valued attributes whose values will always be maintained in sorted order.
Using this option will allow Modify, Compare, and filter evaluations on these attributes to be
performed more efficiently. The resulting sort order depends on the attributes' syntax and
matching rules and may not correspond to lexical order or any other recognizable order. This
setting is only allowed in the frontend entry.
olcTimeLimit: {<integer>|unlimited}
olcTimeLimit: time[.{soft|hard}]=<integer> [...]
Specify the maximum number of seconds (in real time) slapd will spend answering a search request.
The default time limit is 3600. Use unlimited to specify no limits. The second format allows a
fine grain setting of the time limits. Extra args can be added in the same value. See olcLimits
for an explanation of the different flags.
GENERAL DATABASE OPTIONS
Options in this section only apply to the specific database for which they are defined. They are
supported by every type of backend. All of the Global Database Options may also be used here.
olcAddContentAcl: TRUE | FALSE
Controls whether Add operations will perform ACL checks on the content of the entry being added.
This check is off by default. See the slapd.access(5) manual page for more details on ACL
requirements for Add operations.
olcHidden: TRUE | FALSE
Controls whether the database will be used to answer queries. A database that is hidden will never
be selected to answer any queries, and any suffix configured on the database will be ignored in
checks for conflicts with other databases. By default, olcHidden is FALSE.
olcLastMod: TRUE | FALSE
Controls whether slapd will automatically maintain the modifiersName, modifyTimestamp,
creatorsName, and createTimestamp attributes for entries. It also controls the entryCSN and
entryUUID attributes, which are needed by the syncrepl provider. By default, olcLastMod is TRUE.
olcLastBind: TRUE | FALSE
Controls whether slapd will automatically maintain the pwdLastSuccess attribute for entries. By
default, olcLastBind is FALSE.
olcLastBindPrecision: <integer>
If olcLastBind is enabled, specifies how frequently pwdLastSuccess will be updated. More than
integer seconds must have passed since the last successful bind. In a replicated environment with
frequent bind activity it may be useful to set this to a large value.
olcLimits: <selector> <limit> [<limit> [...]]
Specify time and size limits based on the operation's initiator or base DN. The argument
<selector> can be any of
anonymous | users | [<dnspec>=]<pattern> | group[/oc[/at]]=<pattern>
with
<dnspec> ::= dn[.<type>][.<style>]
<type> ::= self | this
<style> ::= exact | base | onelevel | subtree | children | regex | anonymous
DN type self is the default and means the bound user, while this means the base DN of the
operation. The term anonymous matches all unauthenticated clients. The term users matches all
authenticated clients; otherwise an exact dn pattern is assumed unless otherwise specified by
qualifying the (optional) key string dn with exact or base (which are synonyms), to require an
exact match; with onelevel, to require exactly one level of depth match; with subtree, to allow
any level of depth match, including the exact match; with children, to allow any level of depth
match, not including the exact match; regex explicitly requires the (default) match based on POSIX
(''extended'') regular expression pattern. Finally, anonymous matches unbound operations; the
pattern field is ignored. The same behavior is obtained by using the anonymous form of the
<selector> clause. The term group, with the optional objectClass oc and attributeType at fields,
followed by pattern, sets the limits for any DN listed in the values of the at attribute (default
member) of the oc group objectClass (default groupOfNames) whose DN exactly matches pattern.
The currently supported limits are size and time.
The syntax for time limits is time[.{soft|hard}]=<integer>, where integer is the number of seconds
slapd will spend answering a search request. If no time limit is explicitly requested by the
client, the soft limit is used; if the requested time limit exceeds the hard limit, the value of
the limit is used instead. If the hard limit is set to the keyword soft, the soft limit is used
in either case; if it is set to the keyword unlimited, no hard limit is enforced. Explicit
requests for time limits smaller or equal to the hard limit are honored. If no limit specifier is
set, the value is assigned to the soft limit, and the hard limit is set to soft, to preserve the
original behavior.
The syntax for size limits is size[.{soft|hard|unchecked}]=<integer>, where integer is the maximum
number of entries slapd will return answering a search request. If no size limit is explicitly
requested by the client, the soft limit is used; if the requested size limit exceeds the hard
limit, the value of the limit is used instead. If the hard limit is set to the keyword soft, the
soft limit is used in either case; if it is set to the keyword unlimited, no hard limit is
enforced. Explicit requests for size limits smaller or equal to the hard limit are honored. The
unchecked specifier sets a limit on the number of candidates a search request is allowed to
examine. The rationale behind it is that searches for non-properly indexed attributes may result
in large sets of candidates, which must be examined by slapd(8) to determine whether they match
the search filter or not. The unchecked limit provides a means to drop such operations before
they are even started. If the selected candidates exceed the unchecked limit, the search will
abort with Unwilling to perform. If it is set to the keyword unlimited, no limit is applied (the
default). If it is set to disabled, the search is not even performed; this can be used to
disallow searches for a specific set of users. If no limit specifier is set, the value is
assigned to the soft limit, and the hard limit is set to soft, to preserve the original behavior.
In case of no match, the global limits are used. The default values are the same as for
olcSizeLimit and olcTimeLimit; no limit is set on unchecked.
If pagedResults control is requested, the hard size limit is used by default, because the request
of a specific page size is considered an explicit request for a limitation on the number of
entries to be returned. However, the size limit applies to the total count of entries returned
within the search, and not to a single page. Additional size limits may be enforced; the syntax
is size.pr={<integer>|noEstimate|unlimited}, where integer is the max page size if no explicit
limit is set; the keyword noEstimate inhibits the server from returning an estimate of the total
number of entries that might be returned (note: the current implementation does not return any
estimate). The keyword unlimited indicates that no limit is applied to the pagedResults control
page size. The syntax size.prtotal={<integer>|hard|unlimited|disabled} allows one to set a limit
on the total number of entries that the pagedResults control will return. By default it is set to
the hard limit which will use the size.hard value. When set, integer is the max number of entries
that the whole search with pagedResults control can return. Use unlimited to allow unlimited
number of entries to be returned, e.g. to allow the use of the pagedResults control as a means to
circumvent size limitations on regular searches; the keyword disabled disables the control, i.e.
no paged results can be returned. Note that the total number of entries returned when the
pagedResults control is requested cannot exceed the hard size limit of regular searches unless
extended by the prtotal switch.
The olcLimits statement is typically used to let an unlimited number of entries be returned by
searches performed with the identity used by the consumer for synchronization purposes by means of
the RFC 4533 LDAP Content Synchronization protocol (see olcSyncrepl for details).
When using subordinate databases, it is necessary for any limits that are to be applied across the
parent and its subordinates to be defined in both the parent and its subordinates. Otherwise the
settings on the subordinate databases are not honored.
olcMaxDerefDepth: <depth>
Specifies the maximum number of aliases to dereference when trying to resolve an entry, used to
avoid infinite alias loops. The default is 15.
olcMultiProvider: TRUE | FALSE
This option puts a consumer database into Multi-Provider mode. Update operations will be accepted
from any user, not just the updatedn. The database must already be configured as a syncrepl
consumer before this keyword may be set. This mode also requires a olcServerID (see above) to be
configured. By default, this setting is FALSE.
olcMonitoring: TRUE | FALSE
This option enables database-specific monitoring in the entry related to the current database in
the "cn=Databases,cn=Monitor" subtree of the monitor database, if the monitor database is enabled.
Currently, only the MDB database provides database-specific monitoring. If monitoring is
supported by the backend it defaults to TRUE, otherwise FALSE.
olcPlugin: <plugin_type> <lib_path> <init_function> [<arguments>]
Configure a SLAPI plugin. See the slapd.plugin(5) manpage for more details.
olcRootDN: <dn>
Specify the distinguished name that is not subject to access control or administrative limit
restrictions for operations on this database. This DN may or may not be associated with an entry.
An empty root DN (the default) specifies no root access is to be granted. It is recommended that
the rootdn only be specified when needed (such as when initially populating a database). If the
rootdn is within a namingContext (suffix) of the database, a simple bind password may also be
provided using the olcRootPW directive. Many optional features, including syncrepl, require the
rootdn to be defined for the database. The olcRootDN of the cn=config database defaults to
cn=config itself.
olcRootPW: <password>
Specify a password (or hash of the password) for the rootdn. The password can only be set if the
rootdn is within the namingContext (suffix) of the database. This option accepts all RFC 2307
userPassword formats known to the server (see olcPasswordHash description) as well as cleartext.
slappasswd(8) may be used to generate a hash of a password. Cleartext and {CRYPT} passwords are
not recommended. If empty (the default), authentication of the root DN is by other means (e.g.
SASL). Use of SASL is encouraged.
olcSubordinate: [TRUE | FALSE | advertise]
Specify that the current backend database is a subordinate of another backend database. A
subordinate database may have only one suffix. This option may be used to glue multiple databases
into a single namingContext. If the suffix of the current database is within the namingContext of
a superior database, searches against the superior database will be propagated to the subordinate
as well. All of the databases associated with a single namingContext should have identical
rootdns. Behavior of other LDAP operations is unaffected by this setting. In particular, it is
not possible to use moddn to move an entry from one subordinate to another subordinate within the
namingContext.
If the optional advertise flag is supplied, the naming context of this database is advertised in
the root DSE. The default is to hide this database context, so that only the superior context is
visible.
If the slap tools slapcat(8), slapadd(8), slapmodify(8), or slapindex(8) are used on the superior
database, any glued subordinates that support these tools are opened as well.
Databases that are glued together should usually be configured with the same indices (assuming
they support indexing), even for attributes that only exist in some of these databases. In
general, all of the glued databases should be configured as similarly as possible, since the
intent is to provide the appearance of a single directory.
Note that the subordinate functionality is implemented internally by the glue overlay and as such
its behavior will interact with other overlays in use. By default, the glue overlay is
automatically configured as the last overlay on the superior database. Its position on the
database can be explicitly configured by setting an overlay glue directive at the desired
position. This explicit configuration is necessary e.g. when using the syncprov overlay, which
needs to follow glue in order to work over all of the glued databases. E.g.
dn: olcDatabase={1}mdb,cn=config
olcSuffix: dc=example,dc=com
...
dn: olcOverlay={0}glue,olcDatabase={1}mdb,cn=config
...
dn: olcOverlay={1}syncprov,olcDatabase={1}mdb,cn=config
...
See the Overlays section below for more details.
olcSuffix: <dn suffix>
Specify the DN suffix of queries that will be passed to this backend database. Multiple suffix
lines can be given and at least one is required for each database definition.
If the suffix of one database is "inside" that of another, the database with the inner suffix must
come first in the configuration file. You may also want to glue such databases together with the
olcSubordinate attribute.
olcSyncUseSubentry: TRUE | FALSE
Store the syncrepl contextCSN in a subentry instead of the context entry of the database. The
subentry's RDN will be "cn=ldapsync". The default is FALSE, meaning the contextCSN is stored in
the context entry.
olcSyncrepl: rid=<replica ID> provider=ldap[s]://<hostname>[:port] searchbase=<base DN>
[type=refreshOnly|refreshAndPersist] [interval=dd:hh:mm:ss] [retry=[<retry interval> <# of
retries>]+] [filter=<filter str>] [scope=sub|one|base|subord] [attrs=<attr list>] [exattrs=<attr
list>] [attrsonly] [sizelimit=<limit>] [timelimit=<limit>] [schemachecking=on|off]
[network-timeout=<seconds>] [timeout=<seconds>] [tcp-user-timeout=<milliseconds>]
[bindmethod=simple|sasl] [binddn=<dn>] [saslmech=<mech>] [authcid=<identity>] [authzid=<identity>]
[credentials=<passwd>] [realm=<realm>] [secprops=<properties>]
[keepalive=<idle>:<probes>:<interval>] [starttls=yes|critical] [tls_cert=<file>] [tls_key=<file>]
[tls_cacert=<file>] [tls_cacertdir=<path>] [tls_reqcert=never|allow|try|demand]
[tls_reqsan=never|allow|try|demand] [tls_cipher_suite=<ciphers>] [tls_ecname=<names>]
[tls_crlcheck=none|peer|all] [tls_protocol_min=<major>[.<minor>]] [suffixmassage=<real DN>]
[logbase=<base DN>] [logfilter=<filter str>] [syncdata=default|accesslog|changelog] [lazycommit]
Specify the current database as a consumer which is kept up-to-date with the provider content by
establishing the current slapd(8) as a replication consumer site running a syncrepl replication
engine. The consumer content is kept synchronized to the provider content using the LDAP Content
Synchronization protocol. Refer to the "OpenLDAP Administrator's Guide" for detailed information
on setting up a replicated slapd directory service using the syncrepl replication engine.
rid identifies the current syncrepl directive within the replication consumer site. It is a non-
negative integer not greater than 999 (limited to three decimal digits).
provider specifies the replication provider site containing the provider content as an LDAP URI.
If <port> is not given, the standard LDAP port number (389 or 636) is used.
The content of the syncrepl consumer is defined using a search specification as its result set.
The consumer slapd will send search requests to the provider slapd according to the search
specification. The search specification includes searchbase, scope, filter, attrs, attrsonly,
sizelimit, and timelimit parameters as in the normal search specification. The exattrs option may
also be used to specify attributes that should be omitted from incoming entries. The scope
defaults to sub, the filter defaults to (objectclass=*), and there is no default searchbase. The
attrs list defaults to "*,+" to return all user and operational attributes, and attrsonly and
exattrs are unset by default. The sizelimit and timelimit only accept "unlimited" and positive
integers, and both default to "unlimited". The sizelimit and timelimit parameters define a
consumer requested limitation on the number of entries that can be returned by the LDAP Content
Synchronization operation; these should be left unchanged from the default otherwise replication
may never succeed. Note, however, that any provider-side limits for the replication identity will
be enforced by the provider regardless of the limits requested by the LDAP Content Synchronization
operation, much like for any other search operation.
The LDAP Content Synchronization protocol has two operation types. In the refreshOnly operation,
the next synchronization search operation is periodically rescheduled at an interval time
(specified by interval parameter; 1 day by default) after each synchronization operation finishes.
In the refreshAndPersist operation, a synchronization search remains persistent in the provider
slapd. Further updates to the provider will generate searchResultEntry to the consumer slapd as
the search responses to the persistent synchronization search. If the initial search fails due to
an error, the next synchronization search operation is periodically rescheduled at an interval
time (specified by interval parameter; 1 day by default)
If an error occurs during replication, the consumer will attempt to reconnect according to the
retry parameter which is a list of the <retry interval> and <# of retries> pairs. For example,
retry="60 10 300 3" lets the consumer retry every 60 seconds for the first 10 times and then retry
every 300 seconds for the next 3 times before stop retrying. The `+' in <# of retries> means
indefinite number of retries until success. If no retry is specified, by default syncrepl retries
every hour forever.
The schema checking can be enforced at the LDAP Sync consumer site by turning on the
schemachecking parameter. The default is off. Schema checking on means that replicated entries
must have a structural objectClass, must obey to objectClass requirements in terms of
required/allowed attributes, and that naming attributes and distinguished values must be present.
As a consequence, schema checking should be off when partial replication is used.
The network-timeout parameter sets how long the consumer will wait to establish a network
connection to the provider. Once a connection is established, the timeout parameter determines how
long the consumer will wait for the initial Bind request to complete. The defaults for these
parameters come from ldap.conf(5). The tcp-user-timeout parameter, if non-zero, corresponds to
the TCP_USER_TIMEOUT set on the target connections, overriding the operating system setting. Only
some systems support the customization of this parameter, it is ignored otherwise and system-wide
settings are used.
A bindmethod of simple requires the options binddn and credentials and should only be used when
adequate security services (e.g. TLS or IPSEC) are in place. REMEMBER: simple bind credentials
must be in cleartext! A bindmethod of sasl requires the option saslmech. Depending on the
mechanism, an authentication identity and/or credentials can be specified using authcid and
credentials. The authzid parameter may be used to specify an authorization identity. Specific
security properties (as with the sasl-secprops keyword above) for a SASL bind can be set with the
secprops option. A non default SASL realm can be set with the realm option. The identity used for
synchronization by the consumer should be allowed to receive an unlimited number of entries in
response to a search request. The provider, other than allowing authentication of the syncrepl
identity, should grant that identity appropriate access privileges to the data that is being
replicated (access directive), and appropriate time and size limits. This can be accomplished by
either allowing unlimited sizelimit and timelimit, or by setting an appropriate limits statement
in the consumer's configuration (see sizelimit and limits for details).
The keepalive parameter sets the values of idle, probes, and interval used to check whether a
socket is alive; idle is the number of seconds a connection needs to remain idle before TCP starts
sending keepalive probes; probes is the maximum number of keepalive probes TCP should send before
dropping the connection; interval is interval in seconds between individual keepalive probes.
Only some systems support the customization of these values; the keepalive parameter is ignored
otherwise, and system-wide settings are used.
The starttls parameter specifies use of the StartTLS extended operation to establish a TLS session
before Binding to the provider. If the critical argument is supplied, the session will be aborted
if the StartTLS request fails. Otherwise the syncrepl session continues without TLS. The
tls_reqcert setting defaults to "demand", the tls_reqsan setting defaults to "allow", and the
other TLS settings default to the same as the main slapd TLS settings.
The suffixmassage parameter allows the consumer to pull entries from a remote directory whose DN
suffix differs from the local directory. The portion of the remote entries' DNs that matches the
searchbase will be replaced with the suffixmassage DN.
Rather than replicating whole entries, the consumer can query logs of data modifications. This
mode of operation is referred to as delta syncrepl. In addition to the above parameters, the
logbase and logfilter parameters must be set appropriately for the log that will be used. The
syncdata parameter must be set to either "accesslog" if the log conforms to the slapo-accesslog(5)
log format, or "changelog" if the log conforms to the obsolete changelog format. If the syncdata
parameter is omitted or set to "default" then the log parameters are ignored.
The lazycommit parameter tells the underlying database that it can store changes without
performing a full flush after each change. This may improve performance for the consumer, while
sacrificing safety or durability.
olcUpdateDN: <dn>
This option is only applicable in a replica database. It specifies the DN permitted to update
(subject to access controls) the replica. It is only needed in certain push-mode replication
scenarios. Generally, this DN should not be the same as the rootdn used at the provider.
olcUpdateRef: <url>
Specify the referral to pass back when slapd(8) is asked to modify a replicated local database.
If multiple values are specified, each url is provided.
DATABASE-SPECIFIC OPTIONS
Each database may allow specific configuration options; they are documented separately in the backends'
manual pages. See the slapd.backends(5) manual page for an overview of available backends.
OVERLAYS
An overlay is a piece of code that intercepts database operations in order to extend or change them.
Overlays are pushed onto a stack over the database, and so they will execute in the reverse of the order
in which they were configured and the database itself will receive control last of all.
Overlays must be configured as child entries of a specific database. The entry's RDN must be of the form
olcOverlay={x}<overlaytype> and the entry must have the olcOverlayConfig objectClass. Normally the config
engine generates the "{x}" index in the RDN automatically, so it can be omitted when initially loading
these entries.
See the slapd.overlays(5) manual page for an overview of available overlays.
EXAMPLES
Here is a short example of a configuration in LDIF suitable for use with slapadd(8) :
dn: cn=config
objectClass: olcGlobal
cn: config
olcPidFile: /var/run/slapd.pid
olcAttributeOptions: x-hidden lang-
dn: cn=schema,cn=config
objectClass: olcSchemaConfig
cn: schema
include: file:///etc/ldap/schema/core.ldif
dn: olcDatabase=frontend,cn=config
objectClass: olcDatabaseConfig
objectClass: olcFrontendConfig
olcDatabase: frontend
# Subtypes of "name" (e.g. "cn" and "ou") with the
# option ";x-hidden" can be searched for/compared,
# but are not shown. See slapd.access(5).
olcAccess: to attrs=name;x-hidden by * =cs
# Protect passwords. See slapd.access(5).
olcAccess: to attrs=userPassword by * auth
# Read access to other attributes and entries.
olcAccess: to * by * read
# set a rootpw for the config database so we can bind.
# deny access to everyone else.
dn: olcDatabase=config,cn=config
objectClass: olcDatabaseConfig
olcDatabase: config
olcRootPW: {SSHA}XKYnrjvGT3wZFQrDD5040US592LxsdLy
olcAccess: to * by * none
dn: olcDatabase=mdb,cn=config
objectClass: olcDatabaseConfig
objectClass: olcMdbConfig
olcDatabase: mdb
olcSuffix: "dc=our-domain,dc=com"
# The database directory MUST exist prior to
# running slapd AND should only be accessible
# by the slapd/tools. Mode 0700 recommended.
olcDbDirectory: /var/lib/ldap
# Indices to maintain
olcDbIndex: objectClass eq
olcDbIndex: cn,sn,mail pres,eq,approx,sub
# We serve small clients that do not handle referrals,
# so handle remote lookups on their behalf.
dn: olcDatabase=ldap,cn=config
objectClass: olcDatabaseConfig
objectClass: olcLdapConfig
olcDatabase: ldap
olcSuffix: ""
olcDbUri: ldap://ldap.some-server.com/
Assuming the above data was saved in a file named "config.ldif" and the /etc/ldap/slapd.d directory has
been created, this command will initialize the configuration:
slapadd -F /etc/ldap/slapd.d -n 0 -l config.ldif
"OpenLDAP Administrator's Guide" contains a longer annotated example of a slapd configuration.
Alternatively, an existing slapd.conf file can be converted to the new format using slapd or any of the
slap tools:
slaptest -f /etc/ldap/slapd.conf -F /etc/ldap/slapd.d
FILES
/etc/ldap/slapd.conf
default slapd configuration file
/etc/ldap/slapd.d
default slapd configuration directory
SEE ALSO
ldap(3), ldif(5), gnutls-cli(1), slapd.access(5), slapd.backends(5), slapd.conf(5), slapd.overlays(5),
slapd.plugin(5), slapd(8), slapacl(8), slapadd(8), slapauth(8), slapcat(8), slapdn(8), slapindex(8),
slapmodify(8), slappasswd(8), slaptest(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 the University of Michigan LDAP 3.3 Release.
OpenLDAP 2.6.9+dfsg-2ubuntu1 2024/11/26 SLAPD-CONFIG(5)