SLAPD.CONF(5)SLAPD.CONF(5)NAMEslapd.conf - configuration file for slapd, the stand-alone LDAP daemon
SYNOPSIS
/etc/openldap/slapd.conf
DESCRIPTION
The file /etc/openldap/slapd.conf contains configuration information
for the slapd(8) daemon. This configuration file is also used by the
slurpd(8) replication daemon and by the SLAPD tools slapacl(8), sla‐
padd(8), slapauth(8), slapcat(8), slapdn(8), slapindex(8), and
slaptest(8).
The slapd.conf file consists of a series of global configuration
options that apply to slapd as a whole (including all backends), fol‐
lowed by zero or more database backend definitions that contain infor‐
mation specific to a backend instance. The configuration options are
case-insensitive; their value, on a case by case basis, may be case-
sensitive.
The general format of slapd.conf is as follows:
# comment - these options apply to every database
<global configuration options>
# first database definition & configuration options
database <backend 1 type>
<configuration options specific to backend 1>
# subsequent database definitions & configuration options
...
As many backend-specific sections as desired may be included. Global
options can be overridden in a backend (for options that appear more
than once, the last appearance in the slapd.conf file is used).
If a line begins with white space, it is considered a continuation of
the previous line. Blank lines and comment lines beginning with a `#'
character are ignored. Note: continuation lines are unwrapped before
comment processing is applied.
Arguments on configuration lines are separated by white space. If an
argument contains white space, the argument should be enclosed in dou‐
ble quotes. If an argument contains a double quote (`"') or a back‐
slash character (`\'), the character should be preceded by a backslash
character.
The specific configuration options available are discussed below in the
Global Configuration Options, General Backend Options, and General
Database Options. Backend-specific options are discussed in the
slapd-<backend>(5) manual pages. Refer to the "OpenLDAP Administra‐
tor's Guide" for more details on the slapd configuration file.
GLOBAL CONFIGURATION OPTIONS
Options described in this section apply to all backends, unless specif‐
ically overridden in a backend definition. Arguments that should be
replaced by actual text are shown in brackets <>.
access 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., "access to * by * read").
The rootdn can always read and write EVERYTHING! See
slapd.access(5) and the "OpenLDAP's Administrator's Guide" for
details.
allow <features>
Specify a set of features (separated by white space) 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).
argsfile <filename>
The ( absolute ) name of a file that will hold the slapd
server's command line options if started without the debugging
command line option.
attributeoptions [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 attributeoptions
directive, `lang-' will no longer be defined and you must spec‐
ify 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 2251 reserves options beginning with `x-' for private exper‐
iments. Other options should be registered with IANA, see RFC
3383 section 3.4. OpenLDAP also has the `binary' option built
in, but this is a transfer option, not a tagging option.
attributetype ( <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
2252. The slapd parser extends the RFC 2252 definition by
allowing string forms as well as numeric OIDs to be used for the
attribute OID and attribute syntax OID. (See the
objectidentifier description.)
authz-policy <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 three 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, consisting of the keyword
group, optionally followed by the specification of the group
objectClass and member attributeType. The group with DN
<pattern> is searched with base scope, and in case of match, the
values of the member attributeType are searched for the asserted
DN. 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
authz-regexp statement (see below); significantly, the URI and
the dn.exact:<dn> forms.
authz-regexp <match> <replace>
Used by the authentication framework to convert simple user
names, such as provided by SASL subsystem, to an LDAP DN used
for authorization purposes. Note that the resultant 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.
Multiple authz-regexp options can be given in the configuration
file to allow for multiple matching and replacement patterns.
The matching patterns are checked in the order they appear in
the file, stopping at the first successful match.
concurrency <integer>
Specify a desired level of concurrency. Provided to the
underlying thread system as a hint. The default is not to
provide any hint.
conn_max_pending <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.
conn_max_pending_auth <integer>
Specify the maximum number of pending requests for an
authenticated session. The default is 1000.
defaultsearchbase <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.
disallow <features>
Specify a set of features (separated by white space) 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)uponStartTLSoperationreceipt. tls_authc dissallow the
StartTLS operation if authenticated (see also tls_2_anon).
ditcontentrule ( <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 2252. The slapd parser extends the RFC 2252 definition by
allowing string forms as well as numeric OIDs to be used for the
attribute OID and attribute syntax OID. (See the
objectidentifier description.)
gentlehup { on | off }
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 off. You may wish to
use idletimeout along with this option.
idletimeout <integer>
Specify the number of seconds to wait before forcibly closing an
idle client connection. A idletimeout of 0 disables this
feature. The default is 0.
include <filename>
Read additional configuration information from the given file
before continuing with the next line of the current file.
index_substr_if_minlen <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.
index_substr_if_maxlen <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.
index_substr_any_len <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
index_substr_if_maxlen value.
index_substr_any_step <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".
localSSF <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 sasl-secprops's minssf option
description. The default is 71.
loglevel <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 some logging is configured,
otherwise anything is logged at all. Log levels are additive,
and available levels are:
1 (0x1 trace) trace function calls
2 (0x2 packet) 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) stats log
connections/operations/results
512 (0x200 stats2) stats log entries sent
1024 (0x400 shell) print communication with shell
backends
2048 (0x800 parse) entry parsing
4096 (0x1000 cache) caching (unused)
8192 (0x2000 index) data indexing (unused)
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
brackets, such that
loglevel 129
loglevel 0x81
loglevel 128 1
loglevel 0x80 0x1
loglevel 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 loglevel
to be logged. In fact, if no loglevel (or a 0 level) is
defined, no logging occurs, so at least the none level is
required to have high priority messages logged.
moduleload <filename>
Specify the name of a dynamically loadable module to load. The
filename may be an absolute path name or a simple filename. Non-
absolute names are searched for in the directories specified by
the modulepath option. This option and the modulepath option are
only usable if slapd was compiled with --enable-modules.
modulepath <pathspec>
Specify a list of directories to search for loadable modules.
Typically the path is colon-separated but this depends on the
operating system.
objectclass ( <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
2252. The slapd parser extends the RFC 2252 definition by
allowing string forms as well as numeric OIDs to be used for the
object class OID. (See the objectidentifier description.)
Object classes are "STRUCTURAL" by default.
objectidentifier <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.
password-hash <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.
password-crypt-salt-format <format>
Specify the format of the salt passed to crypt(3) when
generating {CRYPT} passwords (see password-hash) 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.
pidfile <filename>
The ( absolute ) name of a file that will hold the slapd
server's process ID ( see getpid(2) ) if started without the
debugging command line option.
referral <url>
Specify the referral to pass back when slapd(8) cannot find a
local database to handle a request. If specified multiple
times, each url is provided.
replica-argsfile
The ( absolute ) name of a file that will hold the slurpd
server's command line options if started without the debugging
command line option.
replica-pidfile
The ( absolute ) name of a file that will hold the slurpd
server's process ID ( see getpid(2) ) if started without the
debugging command line option.
replicationinterval
The number of seconds slurpd waits before checking the
replogfile for changes.
require <conditions>
Specify a set of conditions (separated by white space) to
require (default none). The directive may be specified globally
and/or per-database. 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 for clearly globally set conditions within a particular
database).
reverse-lookup on | off
Enable/disable client name unverified reverse lookup (default is
off if compiled with --enable-rlookups).
rootDSE <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.
sasl-host <fqdn>
Used to specify the fully qualified domain name used for SASL
processing.
sasl-realm <realm>
Specify SASL realm. Default is empty.
sasl-secprops <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, 56 allows DES or other weak ciphers,
112 allows triple DES and other strong ciphers, 128 allows RC4,
Blowfish and other modern strong 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.
schemadn <dn>
Specify the distinguished name for the subschema subentry that
controls the entries on this server. The default is
"cn=Subschema".
security <factors>
Specify a set of security strength factors (separated by white
space) to require (see sasl-secprops'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.
sizelimit {<integer>|unlimited}
sizelimit size[.{soft|hard|unchecked}]=<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. Extra args can be added on the same
line. See limits for an explanation of the different flags.
sockbuf_max_incoming <integer>
Specify the maximum incoming LDAP PDU size for anonymous
sessions. The default is 262143.
sockbuf_max_incoming_auth <integer>
Specify the maximum incoming LDAP PDU size for authenticated
sessions. The default is 4194303.
threads <integer>
Specify the maximum size of the primary thread pool. The
default is 16; the minimum value is 2.
timelimit {<integer>|unlimited}
timelimit 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 on the same line. See limits for an explanation of the
different flags.
tool-threads <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.
TLS OPTIONS
If slapd is built with support for Transport Layer Security, there are
more options you can specify.
TLSCipherSuite <cipher-suite-spec>
Permits configuring what ciphers will be accepted and the
preference order. <cipher-suite-spec> should be a cipher
specification for OpenSSL. Example:
TLSCipherSuite HIGH:MEDIUM:+SSLv2
To check what ciphers a given spec selects, use:
openssl ciphers -v <cipher-suite-spec>
TLSCACertificateFile <filename>
Specifies the file that contains certificates for all of the
Certificate Authorities that slapd will recognize.
TLSCACertificatePath <path>
Specifies the path of a directory that contains Certificate
Authority certificates in separate individual files. Usually
only one of this or the TLSCACertificateFile is used.
TLSCertificateFile <filename>
Specifies the file that contains the slapd server certificate.
TLSCertificateKeyFile <filename>
Specifies the file that contains the slapd server private key
that matches the certificate stored in the TLSCertificateFile
file. Currently, the private key must not be protected with a
password, so it is of critical importance that it is protected
carefully.
TLSDHParamFile <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. If multiple sets
of parameters are present in the file, all of them will be
processed. Note that setting this option may also enable
Anonymous Diffie-Hellman key exchanges in certain non-default
cipher suites. You should append "!ADH" to your cipher suites
if you have changed them from the default, otherwise no
certificate exchanges or verification will be done.
TLSRandFile <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.
TLSVerifyClient <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 TLSVerifyClient
setting must be chosen to enable SASL EXTERNAL
authentication.
TLSCRLCheck <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 TLSCACertificatePath parameter to be
set. <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
GENERAL BACKEND OPTIONS
Options in this section only apply to the configuration file section
for the specified backend. They are supported by every type of
backend.
backend <databasetype>
Mark the beginning of a backend definition. <databasetype>
should be one of bdb, config, dnssrv, hdb, ldap, ldbm, ldif,
meta, monitor, null, passwd, perl, relay, shell, or sql,
depending on which backend will serve the database.
GENERAL DATABASE OPTIONS
Options in this section only apply to the configuration file section
for the database in which they are defined. They are supported by
every type of backend. Note that the database and at least one suffix
option are mandatory for each database.
database <databasetype>
Mark the beginning of a new database instance definition.
<databasetype> should be one of bdb, config, dnssrv, hdb, ldap,
ldbm, ldif, meta, monitor, null, passwd, perl, relay, shell, or
sql, depending on which backend will serve the database.
lastmod on | off
Controls whether slapd will automatically maintain the
modifiersName, modifyTimestamp, creatorsName, and
createTimestamp attributes for entries. By default, lastmod is
on.
limits <who> <limit> [<limit> [...]]
Specify time and size limits based on who initiated an
operation. The argument who can be any of
anonymous | users | [dn[.<style>]=]<pattern> |
group[/oc[/at]]=<pattern>
with
<style> ::= exact | base | onelevel | subtree | children
| regex | anonymous
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 who 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 disable, 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 of sizelimit and timelimit; 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>|unlimited|disabled} allows to set a
limit on the total number of entries that a pagedResults control
allows to return. By default it is set to the hard limit. 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.
maxderefdepth <depth>
Specifies the maximum number of aliases to dereference when
trying to resolve an entry, used to avoid infinite alias loops.
The default is 1.
overlay <overlay-name>
Add the specified overlay to this database. 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.
readonly on | off
This option puts the database into "read-only" mode. Any
attempts to modify the database will return an "unwilling to
perform" error. By default, readonly is off.
replica uri=ldap[s]://<hostname>[:port]|host=<hostname>[:port]
[starttls=yes|critical] [suffix=<suffix> [...]]
bindmethod=simple|sasl [binddn=<simple DN>] [credentials=<simple
password>] [saslmech=<SASL mech>] [secprops=<properties>]
[realm=<realm>] [authcId=<authentication ID>]
[authzId=<authorization ID>] [attr[!]=<attr list>]
Specify a replication site for this database. Refer to the
"OpenLDAP Administrator's Guide" for detailed information on
setting up a replicated slapd directory service. Zero or more
suffix instances can be used to select the subtrees that will be
replicated (defaults to all the database). host is deprecated
in favor of the uri option. uri allows the replica LDAP server
to be specified as an LDAP URI. 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. A
bindmethod of sasl requires the option saslmech. 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. If the
mechanism will use Kerberos, a kerberos instance should be given
in authcId. An attr list can be given after the attr keyword to
allow the selective replication of the listed attributes only;
if the optional ! mark is used, the list is considered
exclusive, i.e. the listed attributes are not replicated. If an
objectClass is listed, all the related attributes are (are not)
replicated.
replogfile <filename>
Specify the name of the replication log file to log changes to.
The replication log is typically written by slapd(8) and read by
slurpd(8). See slapd.replog(5) for more information. The
specified file should be located in a directory with limited
read/write/execute access as the replication logs may contain
sensitive information.
restrict <oplist>
Specify a whitespace separated list of operations that are
restricted. If defined inside a database specification,
restrictions apply only to that database, otherwise they are
global. 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
readonly on (see above). The extended keyword allows to
indicate the OID of the specific operation to be restricted.
rootdn <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 rootpw directive. Note that the rootdn is always needed when
using syncrepl.
rootpw <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 password-
hash 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.
suffix <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.
subordinate [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), 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 backend. Its position on the backend 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.
database bdb
suffix dc=example,dc=com
...
overlay glue
overlay syncprov
syncrepl rid=<replica ID> provider=ldap[s]://<hostname>[:port]
[type=refreshOnly|refreshAndPersist] [interval=dd:hh:mm:ss]
[retry=[<retry interval> <# of retries>]+] [searchbase=<base
DN>] [filter=<filter str>] [scope=sub|one|base] [attrs=<attr
list>] [attrsonly] [sizelimit=<limit>] [timelimit=<limit>]
[schemachecking=on|off] [starttls=yes|critical]
[bindmethod=simple|sasl] [binddn=<dn>] [saslmech=<mech>]
[authcid=<identity>] [authzid=<identity>] [credentials=<passwd>]
[realm=<realm>] [secprops=<properties>] [logbase=<base DN>]
[logfilter=<filter str>] [syncdata=default|accesslog|changelog]
Specify the current database as a replica which is kept up-to-
date with the master content by establishing the current
slapd(8) as a replication consumer site running a syncrepl
replication engine. The replica content is kept synchronized to
the master 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 having no more than three
digits. provider specifies the replication provider site
containing the master 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 replica 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 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 is
unset by default. The sizelimit and timelimit only accept
"unlimited" and positive integers, and both default to
"unlimited". 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 master
replica will generate searchResultEntry to the consumer slapd as
the search responses to the persistent synchronization search.
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. The schema checking
can be enforced at the LDAP Sync consumer site by turning on the
schemachecking parameter. The default is off. 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. 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. 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.
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.
updatedn <dn>
This option is only applicable in a slave database updated using
slurpd(8). It specifies the DN permitted to update (subject to
access controls) the replica (typically, this is the DN
slurpd(8) binds to update the replica). Generally, this DN
should not be the same as the rootdn used at the master.
updateref <url>
Specify the referral to pass back when slapd(8) is asked to
modify a replicated local database. If specified multiple
times, each url is provided.
DATABASE-SPECIFIC OPTIONS
Each database may allow specific configuration options; they are
documented separately in the backends' manual pages.
BACKENDS
The following backends can be compiled into slapd. They are documented
in the slapd-<backend>(5) manual pages.
bdb This is the recommended primary backend for a normal slapd
database. It takes care to configure it properly. It uses the
transactional database interface of the Sleepycat Berkeley DB
(BDB) package to store data.
config This backend is used to manage the configuration of slapd run-
time.
dnssrv This backend is experimental. It serves up referrals based upon
SRV resource records held in the Domain Name System.
hdb This is a variant of the BDB backend that uses a hierarchical
database layout which supports subtree renames.
ldap This backend acts as a proxy to forward incoming requests to
another LDAP server.
ldbm This 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 deprecated in favor of these robust
backends. LDBM uses lightweight non-transactional DB
interfaces, such as those providing by GDBM or Berkeley DB, to
store data.
ldif This database uses the filesystem to build the tree structure of
the database, using plain ascii files to store data. Its usage
should be limited to very simple databases, where performance is
not a requirement.
meta This backend performs basic LDAP proxying with respect to a set
of remote LDAP servers. It is an enhancement of the ldap
backend.
monitor
This backend provides information about the running status of
the slapd daemon.
null Operations in this backend succeed but do nothing.
passwd This backend is provided for demonstration purposes only. It
serves up user account information from the system passwd(5)
file.
perl This backend embeds a perl(1) interpreter into slapd. It runs
Perl subroutines to implement LDAP operations.
relay This backend is experimental. It redirects LDAP operations to
another database in the same server, based on the naming context
of the request. Its use requires the rwm overlay (see slapo-
rwm(5) for details) to rewrite the naming context of the
request. It is primarily intended to implement virtual views on
databases that actually store data.
shell This backend executes external programs to implement LDAP
operations. It is primarily intended to be used in prototypes.
sql This backend is experimental. It services LDAP requests from an
SQL database.
OVERLAYS
The following overlays can be compiled into slapd. They are documented
in the slapo-<overlay>(5) manual pages.
accesslog
Access Logging. This overlay can record accesses to a given
backend database on another database.
auditlog
Audit Logging. This overlay records changes on a given backend
database to an LDIF log file. By default it is not built.
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.
denyop Deny Operation. This overlay allows selected operations to be
denied, similar to the restrict option.
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.
dynlist
Dynamic List. This overlay allows expansion of dynamic groups
and more.
lastmod
Last Modification. This overlay maintains a service entry in
the database with the DN, modification type, modifiersName and
modifyTimestamp of the last write operation performed on that
database.
pcache Proxycache. This overlay allows caching of LDAP search requests
in a local database. It is most often used with the ldap or
meta backends.
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.
refint Referential Integrity. This overlay can be used with a backend
database such as slapd-bdb(5) to maintain the cohesiveness of a
schema which utilizes reference attributes.
retcode
Return Code. This overlay is useful to test the behavior of
clients when server-generated erroneous and/or unusual responses
occur.
rwm Rewrite/remap. This overlay is experimental. It performs basic
DN/data rewrite and objectClass/attributeType mapping.
syncprov
Syncrepl Provider. This overlay implements the provider-side
support for syncrepl replication, including persistent search
functionality.
translucent
Translucent Proxy. This overlay can be used with a backend
database such as slapd-bdb(5) to create a "translucent proxy".
Content of entries retrieved from a remote LDAP server can be
partially overridden by the database.
unique Attribute Uniqueness. This overlay can be used with a backend
database such as slapd-bdb(5) to enforce the uniqueness of some
or all attributes within a subtree.
EXAMPLES
Here is a short example of a configuration file:
include /etc/openldap/schema/core.schema
pidfile /var/slapd.pid
# 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).
attributeoptions x-hidden lang-
access to attr=name;x-hidden by * =cs
# Protect passwords. See slapd.access(5).
access to attrs=userPassword by * auth
# Read access to other attributes and entries.
access to * by * read
database bdb
suffix "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.
directory /var/openldap-data
# Indices to maintain
index objectClass eq
index cn,sn,mail pres,eq,approx,sub
# We serve small clients that do not handle referrals,
# so handle remote lookups on their behalf.
database ldap
suffix ""
uri ldap://ldap.some-server.com/
lastmod off
"OpenLDAP Administrator's Guide" contains a longer annotated example of
a configuration file. The original /etc/openldap/slapd.conf is another
example.
FILES
/etc/openldap/slapd.conf
default slapd configuration file
SEE ALSOldap(3), slapd-bdb(5), slapd-dnssrv(5), slapd-hdb(5), slapd-ldap(5),
slapd-ldbm(5), slapd-ldif(5), slapd-meta(5), slapd-monitor(5),
slapd-null(5), slapd-passwd(5), slapd-perl(5), slapd-relay(5),
slapd-shell(5), slapd-sql(5), slapd.access(5), slapd.plugin(5),
slapd.replog(5), slapd(8), slapacl(8), slapadd(8), slapauth(8),
slapcat(8), slapdn(8), slapindex(8), slappasswd(8), slaptest(8),
slurpd(8).
Known overlays are documented in slapo-accesslog(5), slapo-auditlog(5),
slapo-chain(5), slapo-dynlist(5), slapo-lastmod(5), slapo-pcache(5),
slapo-ppolicy(5), slapo-refint(5), slapo-retcode(5), slapo-rwm(5),
slapo-syncprov(5), slapo-translucent(5), slapo-unique(5).
"OpenLDAP Administrator's Guide" (http://www.OpenLDAP.org/doc/admin/)
ACKNOWLEDGEMENTS
OpenLDAP is developed and maintained by The OpenLDAP Project
(http://www.openldap.org/). OpenLDAP is derived from University of
Michigan LDAP 3.3 Release.
OpenLDAP 2.3.24 2006/05/30 SLAPD.CONF(5)
