man slapd.conf (Formats) - configuration file for slapd, the stand-alone LDAP daemon
NAME
slapd.conf - configuration file for slapd, the stand-alone LDAP daemon
SYNOPSIS
/etc/ldap/slapd.conf
DESCRIPTION
The file /etc/ldap/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 slapadd(8), slapcat(8), and slapindex(8).
The slapd.conf file consists of a series of global configuration options that apply to slapd as a whole (including all backends), followed by zero or more database backend definitions that contain information specific to a backend instance.
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 double quotes. If an argument contains a double quote (`"') or a backslash 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 Administrator's Guide" for more details on the slapd configuration file.
GLOBAL CONFIGURATION OPTIONS
Options described in this section apply to all backends, unless specifically 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>). 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 allow 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 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 2251 reserves options beginning with `x-' for private experiments. 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.)
- 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.
- disallow <features>
- Specify a set of features (separated by white space) to
disallow (default none).
bind_anon
disables acceptance of anonymous bind requests.
bind_simple
disables simple (bind) authentication.
bind_krbv4
disables Kerberos V4 (bind) authentication.
tls_2_anon
disables Start TLS from forcing session to anonymous status (see also
tls_authc).
tls_authc
disables StartTLS 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.
- loglevel <integer>
- Specify the level at which debugging statements and operation statistics should be syslogged (currently logged to the syslogd(8) LOG_LOCAL4 facility). Log levels are additive, and available levels are:
- 1
- trace function calls
- 2
- debug packet handling
- 4
- heavy trace debugging
- 8
- connection management
- 16
- print out packets sent and received
- 32
- search filter processing
- 64
- configuration file processing
- 128
- access control list processing
- 256
- stats log connections/operations/results
- 512
- stats log entries sent
- 1024
- print communication with shell backends
- 2048
- entry parsing
- 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.
{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 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-authz-policy <policy>
- Used to specify which rules to use for SASL 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 saslAuthzFrom attribute of the authorization DN. The to flag will use rules in the saslAuthzTo 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 simply regular expressions specifying which DNs are allowed to perform proxy authorization. The saslAuthzFrom attribute in an entry specifies which other users are allowed to proxy login to this entry. The saslAuthzTo attribute in an entry specifies which other users this user can authorize as. Use of saslAuthzTo rules can be easily abused if users are allowed to write arbitrary values to this attribute. In general the saslAuthzTo attribute must be protected with ACLs such that only privileged users can modify it. The value of saslAuthzFrom and saslAuthzTo describes an identity or a set of identities; it can take three forms:
- ldap:///<base>??[<scope>]?<filter>
- dn[.<dnstyle>]:<pattern> u[<mech>[<realm>]]:<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 saslAuthzFrom or saslAuthzTo. 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 <pattern> to be compiled according to regex(7). 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. 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 saslAuthzFrom and saslAuthzTo can impact security, users are strongly encouraged to explicitly set the type of identity specification that is being used.
- 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-regexp <match> <replace>
- Used by the SASL mechanism to convert a SASL authenticated username 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, the SASL USERNAME, REALM, and MECHANISM are taken, when available, and combined into a SASL name of the form
- UID=<username>[[,CN=<realm>],CN=<mechanism>,]CN=auth
This SASL name is then compared against the match regular expression, and if the match is successful, the SASL 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 SASL 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 SASL name can be either a 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 SASL 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)
Multiple sasl-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.
- 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 factors (separated by white space) to require. An integer value is associated with each factor and is roughly equivalent of the encryption key length to require. A value of 112 is equivalent to 3DES, 128 to Blowfish, etc.. 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 -1 or 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.
- srvtab <filename>
- Specify the srvtab file in which the kerberos keys necessary for authenticating clients using kerberos can be found. This option is only meaningful if you are using Kerberos authentication.
- threads <integer>
- Specify the maximum size of the primary thread pool. The default is 16.
- 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 -1 or 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.
- ucdata-path <path>
- Specify the path to the directory containing the Unicode character tables. The default path is /usr/share/ldap/ucdata.
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.
- 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.
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, dnssrv, ldap, ldbm, meta, monitor, null, passwd, perl, shell, sql, or tcl, 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, dnssrv, ldap, ldbm, meta, monitor, null, passwd, perl, shell, sql, or tcl, 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 regular expression pattern, as detailed in regex(7). 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, an error is returned. If the hard limit is set to 0 or to the keyword soft, the soft limit is used in either case; if it is set to -1 or to the keyword none, no hard limit is enforced. Explicit requests for time limits smaller or equal to the hard limit are honored. If no flag is set, the value is assigned to the soft limit, and the hard limit is set to zero, 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, an error is returned. If the hard limit is set to 0 or to the keyword soft, the soft limit is used in either case; if it is set to -1 or to the keyword none, no hard limit is enforced. Explicit requests for size limits smaller or equal to the hard limit are honored. The unchecked flag sets a limit on the number of candidates a search request is allowed to examine. If the selected candidates exceed the unchecked limit, the search will abort with Unwillingtoperform. If it is set to -1 or to the keyword none, 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 flag is set, the value is assigned to the soft limit, and the hard limit is set to zero, 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 as 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|none}, where integer is the max page size if no explicit limit is set; the keyword noEstimate inhibits the server to return an estimate of the total number of entries that will be returned; the keyword none indicates that no limit is applied to the pagedResults control page size. The syntax size.prtotal={<integer>|none|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 none to allow unlimited number of entries to be returned, i.e. to use pagedResults as a means to allow clients 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.
- 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
- 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.
syncrepl rid=<replica ID>
provider=ldap[s]://<hostname>[:port]
[type=refreshOnly|refreshAndPersist]
[interval=dd:hh:mm:ss]
[searchbase=<base DN>]
[filter=<filter str>]
[scope=sub|one|base]
[attrs=<attr list>]
[attrsonly]
[sizelimit=<limit>]
[timelimit=<limit>]
[schemachecking=on|off]
[updatedn=<dn>]
[starttls=yes|critical]
[bindmethod=simple|sasl]
[binddn=<dn>]
[saslmech=<mech>]
[authcid=<identity>]
[authzid=<identity>]
[credentials=<passwd>]
[realm=<realm>]
[secprops=<properties>]
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 search specification for the LDAP Content Synchronization operation
has the same value syntax and the same default values as in the
ldapsearch(1)
client search tool.
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 the connection is lost, the consumer will
attempt to reconnect at an interval time (specified by
interval
parameter; 60 seconds by default) until the session is re-established.
The schema checking can be enforced at the LDAP Sync
consumer site by turning on the
schemachecking
parameter. The default is off.
The
updatedn
parameter specifies the DN in the consumer site
which is allowed to make changes to the replica.
The DN should have read/write access to the replica database.
Generally, this DN should be the same as the
rootdn
of the replica database and
should not
be the same as the
rootdn
of the master database.
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.
- 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 backend for a normal slapd database. However, it takes more care than with the LDBM backend to configure it properly. It uses the Sleepycat Berkeley DB (BDB) package to store data.
- ldbm
- This is the database backend which is easiest to configure. However, it does not offer the data durability features of the BDB backend. It uses Berkeley DB or GDBM to store data.
- dnssrv
- This backend is experimental. It serves up referrals based upon SRV resource records held in the Domain Name System.
- ldap
- This backend acts as a proxy to forward incoming requests to another LDAP server.
- meta
- This backend performs basic LDAP proxying with respect to a set of remote LDAP servers. It is an enhancement of the ldap backend. The proxy cache extension of meta backend provides answering of search requests from the proxy using results of previously cached requests.
- 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.
- shell
- This backend executes external programs to implement LDAP operations. It is is primarily intended to be used in prototypes.
- sql
- This backend is experimental. It services LDAP requests from an SQL database.
- tcl
- This backend is experimental. It embeds a Tcl(3tcl) interpreter into slapd. It runs Tcl commands to implement LDAP operations.
EXAMPLES
Here is a short example of a configuration file:
include /etc/ldap/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
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/ldap/slapd.conf is another example.
FILES
- /etc/ldap/slapd.conf
- default slapd configuration file
SEE ALSO
ldap(3), slapd-bdb(5), slapd-dnssrv(5), slapd-ldap(5), slapd-ldbm(5), slapd-meta(5), slapd-monitor(5), slapd-null(5), slapd-passwd(5), slapd-perl(5), slapd-shell(5), slapd-sql(5), slapd-tcl(5), slapd.access(5), slapd.plugin(5), slapd.replog(5), slapd(8), slapadd(8), slapcat(8), slapindex(8), slappasswd(8), slurpd(8),
"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.