1SSSD-LDAP(5) File Formats and Conventions SSSD-LDAP(5)
2
6 sssd-ldap - SSSD LDAP provider
7
9 This manual page describes the configuration of LDAP domains for
10 sssd(8). Refer to the “FILE FORMAT” section of the sssd.conf(5) manual
11 page for detailed syntax information.
12 You can configure SSSD to use more than one LDAP domain.
14 LDAP back end supports id, auth, access and chpass providers. If you
16 want to authenticate against an LDAP server either TLS/SSL or LDAPS is
17 required. sssd does not support authentication over an unencrypted
18 channel. If the LDAP server is used only as an identity provider, an
19 encrypted channel is not needed. Please refer to “ldap_access_filter”
20 config option for more information about using LDAP as an access
21 provider.
22
24 All of the common configuration options that apply to SSSD domains also
25 apply to LDAP domains. Refer to the “DOMAIN SECTIONS” section of the
26 sssd.conf(5) manual page for full details. Note that SSSD LDAP mapping
27 attributes are described in the sssd-ldap-attributes(5) manual page.
28 ldap_uri, ldap_backup_uri (string)
30 Specifies the comma-separated list of URIs of the LDAP servers to
31 which SSSD should connect in the order of preference. Refer to the
32 “FAILOVER” section for more information on failover and server
33 redundancy. If neither option is specified, service discovery is
34 enabled. For more information, refer to the “SERVICE DISCOVERY”
35 section.
36 The format of the URI must match the format defined in RFC 2732:
38 ldap[s]://<host>[:port]
40 For explicit IPv6 addresses, <host> must be enclosed in brackets []
42 example: ldap://[fc00::126:25]:389
44 ldap_chpass_uri, ldap_chpass_backup_uri (string)
46 Specifies the comma-separated list of URIs of the LDAP servers to
47 which SSSD should connect in the order of preference to change the
48 password of a user. Refer to the “FAILOVER” section for more
49 information on failover and server redundancy.
50 To enable service discovery ldap_chpass_dns_service_name must be
52 set.
53 Default: empty, i.e. ldap_uri is used.
55 ldap_search_base (string)
57 The default base DN to use for performing LDAP user operations.
58 Starting with SSSD 1.7.0, SSSD supports multiple search bases using
60 the syntax:
61 search_base[?scope?[filter][?search_base?scope?[filter]]*]
63 The scope can be one of "base", "onelevel" or "subtree".
65 The filter must be a valid LDAP search filter as specified by
67 http://www.ietf.org/rfc/rfc2254.txt
68 Examples:
70 ldap_search_base = dc=example,dc=com (which is equivalent to)
72 ldap_search_base = dc=example,dc=com?subtree?
73 ldap_search_base =
75 cn=host_specific,dc=example,dc=com?subtree?(host=thishost)?dc=example.com?subtree?
76 Note: It is unsupported to have multiple search bases which
78 reference identically-named objects (for example, groups with the
79 same name in two different search bases). This will lead to
80 unpredictable behavior on client machines.
81 Default: If not set, the value of the defaultNamingContext or
83 namingContexts attribute from the RootDSE of the LDAP server is
84 used. If defaultNamingContext does not exist or has an empty value
85 namingContexts is used. The namingContexts attribute must have a
86 single value with the DN of the search base of the LDAP server to
87 make this work. Multiple values are are not supported.
88 ldap_schema (string)
90 Specifies the Schema Type in use on the target LDAP server.
91 Depending on the selected schema, the default attribute names
92 retrieved from the servers may vary. The way that some attributes
93 are handled may also differ.
94 Four schema types are currently supported:
96 · rfc2307
98 · rfc2307bis
100 · IPA
102 · AD
104 The main difference between these schema types is how group
106 memberships are recorded in the server. With rfc2307, group members
107 are listed by name in the memberUid attribute. With rfc2307bis and
108 IPA, group members are listed by DN and stored in the member
109 attribute. The AD schema type sets the attributes to correspond
110 with Active Directory 2008r2 values.
111 Default: rfc2307
113 ldap_pwmodify_mode (string)
115 Specify the operation that is used to modify user password.
116 Two modes are currently supported:
118 · exop - Password Modify Extended Operation (RFC 3062)
120 · ldap_modify - Direct modification of userPassword (not
122 recommended).
123 Note: First, a new connection is established to verify current
125 password by binding as the user that requested password change. If
126 successful, this connection is used to change the password
127 therefore the user must have write access to userPassword
128 attribute.
129 Default: exop
131 ldap_default_bind_dn (string)
133 The default bind DN to use for performing LDAP operations.
134 ldap_default_authtok_type (string)
136 The type of the authentication token of the default bind DN.
137 The two mechanisms currently supported are:
139 password
141 obfuscated_password
143 Default: password
145 See the sss_obfuscate(8) manual page for more information.
147 ldap_default_authtok (string)
149 The authentication token of the default bind DN.
150 ldap_force_upper_case_realm (boolean)
152 Some directory servers, for example Active Directory, might deliver
153 the realm part of the UPN in lower case, which might cause the
154 authentication to fail. Set this option to a non-zero value if you
155 want to use an upper-case realm.
156 Default: false
158 ldap_enumeration_refresh_timeout (integer)
160 Specifies how many seconds SSSD has to wait before refreshing its
161 cache of enumerated records.
162 Default: 300
164 ldap_purge_cache_timeout (integer)
166 Determine how often to check the cache for inactive entries (such
167 as groups with no members and users who have never logged in) and
168 remove them to save space.
169 Setting this option to zero will disable the cache cleanup
171 operation. Please note that if enumeration is enabled, the cleanup
172 task is required in order to detect entries removed from the server
173 and can't be disabled. By default, the cleanup task will run every
174 3 hours with enumeration enabled.
175 Default: 0 (disabled)
177 ldap_group_nesting_level (integer)
179 If ldap_schema is set to a schema format that supports nested
180 groups (e.g. RFC2307bis), then this option controls how many levels
181 of nesting SSSD will follow. This option has no effect on the
182 RFC2307 schema.
183 Note: This option specifies the guaranteed level of nested groups
185 to be processed for any lookup. However, nested groups beyond this
186 limit may be returned if previous lookups already resolved the
187 deeper nesting levels. Also, subsequent lookups for other groups
188 may enlarge the result set for original lookup if re-queried.
189 If ldap_group_nesting_level is set to 0 then no nested groups are
191 processed at all. However, when connected to Active-Directory
192 Server 2008 and later using “id_provider=ad” it is furthermore
193 required to disable usage of Token-Groups by setting
194 ldap_use_tokengroups to false in order to restrict group nesting.
195 Default: 2
197 ldap_use_tokengroups
199 This options enables or disables use of Token-Groups attribute when
200 performing initgroup for users from Active Directory Server 2008
201 and later.
202 Default: True for AD and IPA otherwise False.
204 ldap_host_search_base (string)
206 Optional. Use the given string as search base for host objects.
207 See “ldap_search_base” for information about configuring multiple
209 search bases.
210 Default: the value of ldap_search_base
212 ldap_service_search_base (string)
214 An optional base DN, search scope and LDAP filter to restrict LDAP
215 searches for this attribute type.
216 syntax:
218 search_base[?scope?[filter][?search_base?scope?[filter]]*]
220 The scope can be one of "base", "onelevel" or "subtree". The scope
222 functions as specified in section 4.5.1.2 of
223 http://tools.ietf.org/html/rfc4511
224 The filter must be a valid LDAP search filter as specified by
226 http://www.ietf.org/rfc/rfc2254.txt
227 For examples of this syntax, please refer to the “ldap_search_base”
229 examples section.
230 Default: the value of ldap_search_base
232 Please note that specifying scope or filter is not supported for
234 searches against an Active Directory Server that might yield a
235 large number of results and trigger the Range Retrieval extension
236 in the response.
237 ldap_iphost_search_base (string)
239 An optional base DN, search scope and LDAP filter to restrict LDAP
240 searches for this attribute type.
241 syntax:
243 search_base[?scope?[filter][?search_base?scope?[filter]]*]
245 The scope can be one of "base", "onelevel" or "subtree". The scope
247 functions as specified in section 4.5.1.2 of
248 http://tools.ietf.org/html/rfc4511
249 The filter must be a valid LDAP search filter as specified by
251 http://www.ietf.org/rfc/rfc2254.txt
252 For examples of this syntax, please refer to the “ldap_search_base”
254 examples section.
255 Default: the value of ldap_search_base
257 Please note that specifying scope or filter is not supported for
259 searches against an Active Directory Server that might yield a
260 large number of results and trigger the Range Retrieval extension
261 in the response.
262 ldap_ipnetwork_search_base (string)
264 An optional base DN, search scope and LDAP filter to restrict LDAP
265 searches for this attribute type.
266 syntax:
268 search_base[?scope?[filter][?search_base?scope?[filter]]*]
270 The scope can be one of "base", "onelevel" or "subtree". The scope
272 functions as specified in section 4.5.1.2 of
273 http://tools.ietf.org/html/rfc4511
274 The filter must be a valid LDAP search filter as specified by
276 http://www.ietf.org/rfc/rfc2254.txt
277 For examples of this syntax, please refer to the “ldap_search_base”
279 examples section.
280 Default: the value of ldap_search_base
282 Please note that specifying scope or filter is not supported for
284 searches against an Active Directory Server that might yield a
285 large number of results and trigger the Range Retrieval extension
286 in the response.
287 ldap_search_timeout (integer)
289 Specifies the timeout (in seconds) that ldap searches are allowed
290 to run before they are cancelled and cached results are returned
291 (and offline mode is entered)
292 Note: this option is subject to change in future versions of the
294 SSSD. It will likely be replaced at some point by a series of
295 timeouts for specific lookup types.
296 Default: 6
298 ldap_enumeration_search_timeout (integer)
300 Specifies the timeout (in seconds) that ldap searches for user and
301 group enumerations are allowed to run before they are cancelled and
302 cached results are returned (and offline mode is entered)
303 Default: 60
305 ldap_network_timeout (integer)
307 Specifies the timeout (in seconds) after which the
308 poll(2)/select(2) following a connect(2) returns in case of no
309 activity.
310 Default: 6
312 ldap_opt_timeout (integer)
314 Specifies a timeout (in seconds) after which calls to synchronous
315 LDAP APIs will abort if no response is received. Also controls the
316 timeout when communicating with the KDC in case of SASL bind, the
317 timeout of an LDAP bind operation, password change extended
318 operation and the StartTLS operation.
319 Default: 8
321 ldap_connection_expire_timeout (integer)
323 Specifies a timeout (in seconds) that a connection to an LDAP
324 server will be maintained. After this time, the connection will be
325 re-established. If used in parallel with SASL/GSSAPI, the sooner of
326 the two values (this value vs. the TGT lifetime) will be used.
327 This timeout can be extended of a random value specified by
329 ldap_connection_expire_offset
330 Default: 900 (15 minutes)
332 ldap_connection_expire_offset (integer)
334 Random offset between 0 and configured value is added to
335 ldap_connection_expire_timeout.
336 Default: 0
338 ldap_page_size (integer)
340 Specify the number of records to retrieve from LDAP in a single
341 request. Some LDAP servers enforce a maximum limit per-request.
342 Default: 1000
344 ldap_disable_paging (boolean)
346 Disable the LDAP paging control. This option should be used if the
347 LDAP server reports that it supports the LDAP paging control in its
348 RootDSE but it is not enabled or does not behave properly.
349 Example: OpenLDAP servers with the paging control module installed
351 on the server but not enabled will report it in the RootDSE but be
352 unable to use it.
353 Example: 389 DS has a bug where it can only support a one paging
355 control at a time on a single connection. On busy clients, this can
356 result in some requests being denied.
357 Default: False
359 ldap_disable_range_retrieval (boolean)
361 Disable Active Directory range retrieval.
362 Active Directory limits the number of members to be retrieved in a
364 single lookup using the MaxValRange policy (which defaults to 1500
365 members). If a group contains more members, the reply would include
366 an AD-specific range extension. This option disables parsing of the
367 range extension, therefore large groups will appear as having no
368 members.
369 Default: False
371 ldap_sasl_minssf (integer)
373 When communicating with an LDAP server using SASL, specify the
374 minimum security level necessary to establish the connection. The
375 values of this option are defined by OpenLDAP.
376 Default: Use the system default (usually specified by ldap.conf)
378 ldap_sasl_maxssf (integer)
380 When communicating with an LDAP server using SASL, specify the
381 maximal security level necessary to establish the connection. The
382 values of this option are defined by OpenLDAP.
383 Default: Use the system default (usually specified by ldap.conf)
385 ldap_deref_threshold (integer)
387 Specify the number of group members that must be missing from the
388 internal cache in order to trigger a dereference lookup. If less
389 members are missing, they are looked up individually.
390 You can turn off dereference lookups completely by setting the
392 value to 0. Please note that there are some codepaths in SSSD, like
393 the IPA HBAC provider, that are only implemented using the
394 dereference call, so even with dereference explicitly disabled,
395 those parts will still use dereference if the server supports it
396 and advertises the dereference control in the rootDSE object.
397 A dereference lookup is a means of fetching all group members in a
399 single LDAP call. Different LDAP servers may implement different
400 dereference methods. The currently supported servers are 389/RHDS,
401 OpenLDAP and Active Directory.
402 Note: If any of the search bases specifies a search filter, then
404 the dereference lookup performance enhancement will be disabled
405 regardless of this setting.
406 Default: 10
408 ldap_tls_reqcert (string)
410 Specifies what checks to perform on server certificates in a TLS
411 session, if any. It can be specified as one of the following
412 values:
413 never = The client will not request or check any server
415 certificate.
416 allow = The server certificate is requested. If no certificate is
418 provided, the session proceeds normally. If a bad certificate is
419 provided, it will be ignored and the session proceeds normally.
420 try = The server certificate is requested. If no certificate is
422 provided, the session proceeds normally. If a bad certificate is
423 provided, the session is immediately terminated.
424 demand = The server certificate is requested. If no certificate is
426 provided, or a bad certificate is provided, the session is
427 immediately terminated.
428 hard = Same as “demand”
430 Default: hard
432 ldap_tls_cacert (string)
434 Specifies the file that contains certificates for all of the
435 Certificate Authorities that sssd will recognize.
436 Default: use OpenLDAP defaults, typically in
438 /etc/openldap/ldap.conf
439 ldap_tls_cacertdir (string)
441 Specifies the path of a directory that contains Certificate
442 Authority certificates in separate individual files. Typically the
443 file names need to be the hash of the certificate followed by '.0'.
444 If available, cacertdir_rehash can be used to create the correct
445 names.
446 Default: use OpenLDAP defaults, typically in
448 /etc/openldap/ldap.conf
449 ldap_tls_cert (string)
451 Specifies the file that contains the certificate for the client's
452 key.
453 Default: not set
455 ldap_tls_key (string)
457 Specifies the file that contains the client's key.
458 Default: not set
460 ldap_tls_cipher_suite (string)
462 Specifies acceptable cipher suites. Typically this is a colon
463 separated list. See ldap.conf(5) for format.
464 Default: use OpenLDAP defaults, typically in
466 /etc/openldap/ldap.conf
467 ldap_id_use_start_tls (boolean)
469 Specifies that the id_provider connection must also use tls to
470 protect the channel.
471 Default: false
473 ldap_id_mapping (boolean)
475 Specifies that SSSD should attempt to map user and group IDs from
476 the ldap_user_objectsid and ldap_group_objectsid attributes instead
477 of relying on ldap_user_uid_number and ldap_group_gid_number.
478 Currently this feature supports only ActiveDirectory objectSID
480 mapping.
481 Default: false
483 ldap_min_id, ldap_max_id (integer)
485 In contrast to the SID based ID mapping which is used if
486 ldap_id_mapping is set to true the allowed ID range for
487 ldap_user_uid_number and ldap_group_gid_number is unbound. In a
488 setup with sub/trusted-domains this might lead to ID collisions. To
489 avoid collisions ldap_min_id and ldap_max_id can be set to restrict
490 the allowed range for the IDs which are read directly from the
491 server. Sub-domains can then pick other ranges to map IDs.
492 Default: not set (both options are set to 0)
494 ldap_sasl_mech (string)
496 Specify the SASL mechanism to use. Currently only GSSAPI and
497 GSS-SPNEGO are tested and supported.
498 If the backend supports sub-domains the value of ldap_sasl_mech is
500 automatically inherited to the sub-domains. If a different value is
501 needed for a sub-domain it can be overwritten by setting
502 ldap_sasl_mech for this sub-domain explicitly. Please see TRUSTED
503 DOMAIN SECTION in sssd.conf(5) for details.
504 Default: not set
506 ldap_sasl_authid (string)
508 Specify the SASL authorization id to use. When GSSAPI/GSS-SPNEGO
509 are used, this represents the Kerberos principal used for
510 authentication to the directory. This option can either contain the
511 full principal (for example host/myhost@EXAMPLE.COM) or just the
512 principal name (for example host/myhost). By default, the value is
513 not set and the following principals are used:
514 hostname@REALM
516 netbiosname$@REALM
517 host/hostname@REALM
518 *$@REALM
519 host/*@REALM
520 host/*
521 If none of them are found, the first principal in keytab is
524 returned.
525 Default: host/hostname@REALM
527 ldap_sasl_realm (string)
529 Specify the SASL realm to use. When not specified, this option
530 defaults to the value of krb5_realm. If the ldap_sasl_authid
531 contains the realm as well, this option is ignored.
532 Default: the value of krb5_realm.
534 ldap_sasl_canonicalize (boolean)
536 If set to true, the LDAP library would perform a reverse lookup to
537 canonicalize the host name during a SASL bind.
538 Default: false;
540 ldap_krb5_keytab (string)
542 Specify the keytab to use when using SASL/GSSAPI/GSS-SPNEGO.
543 Default: System keytab, normally /etc/krb5.keytab
545 ldap_krb5_init_creds (boolean)
547 Specifies that the id_provider should init Kerberos credentials
548 (TGT). This action is performed only if SASL is used and the
549 mechanism selected is GSSAPI or GSS-SPNEGO.
550 Default: true
552 ldap_krb5_ticket_lifetime (integer)
554 Specifies the lifetime in seconds of the TGT if GSSAPI or
555 GSS-SPNEGO is used.
556 Default: 86400 (24 hours)
558 krb5_server, krb5_backup_server (string)
560 Specifies the comma-separated list of IP addresses or hostnames of
561 the Kerberos servers to which SSSD should connect in the order of
562 preference. For more information on failover and server redundancy,
563 see the “FAILOVER” section. An optional port number (preceded by a
564 colon) may be appended to the addresses or hostnames. If empty,
565 service discovery is enabled - for more information, refer to the
566 “SERVICE DISCOVERY” section.
567 When using service discovery for KDC or kpasswd servers, SSSD first
569 searches for DNS entries that specify _udp as the protocol and
570 falls back to _tcp if none are found.
571 This option was named “krb5_kdcip” in earlier releases of SSSD.
573 While the legacy name is recognized for the time being, users are
574 advised to migrate their config files to use “krb5_server” instead.
575 krb5_realm (string)
577 Specify the Kerberos REALM (for SASL/GSSAPI/GSS-SPNEGO auth).
578 Default: System defaults, see /etc/krb5.conf
580 krb5_canonicalize (boolean)
582 Specifies if the host principal should be canonicalized when
583 connecting to LDAP server. This feature is available with MIT
584 Kerberos >= 1.7
585 Default: false
587 krb5_use_kdcinfo (boolean)
589 Specifies if the SSSD should instruct the Kerberos libraries what
590 realm and which KDCs to use. This option is on by default, if you
591 disable it, you need to configure the Kerberos library using the
592 krb5.conf(5) configuration file.
593 See the sssd_krb5_locator_plugin(8) manual page for more
595 information on the locator plugin.
596 Default: true
598 ldap_pwd_policy (string)
600 Select the policy to evaluate the password expiration on the client
601 side. The following values are allowed:
602 none - No evaluation on the client side. This option cannot disable
604 server-side password policies.
605 shadow - Use shadow(5) style attributes to evaluate if the password
607 has expired.
608 mit_kerberos - Use the attributes used by MIT Kerberos to determine
610 if the password has expired. Use chpass_provider=krb5 to update
611 these attributes when the password is changed.
612 Default: none
614 Note: if a password policy is configured on server side, it always
616 takes precedence over policy set with this option.
617 ldap_referrals (boolean)
619 Specifies whether automatic referral chasing should be enabled.
620 Please note that sssd only supports referral chasing when it is
622 compiled with OpenLDAP version 2.4.13 or higher.
623 Chasing referrals may incur a performance penalty in environments
625 that use them heavily, a notable example is Microsoft Active
626 Directory. If your setup does not in fact require the use of
627 referrals, setting this option to false might bring a noticeable
628 performance improvement. Setting this option to false is therefore
629 recommended in case the SSSD LDAP provider is used together with
630 Microsoft Active Directory as a backend. Even if SSSD would be able
631 to follow the referral to a different AD DC no additional data
632 would be available.
633 Default: true
635 ldap_dns_service_name (string)
637 Specifies the service name to use when service discovery is
638 enabled.
639 Default: ldap
641 ldap_chpass_dns_service_name (string)
643 Specifies the service name to use to find an LDAP server which
644 allows password changes when service discovery is enabled.
645 Default: not set, i.e. service discovery is disabled
647 ldap_chpass_update_last_change (bool)
649 Specifies whether to update the ldap_user_shadow_last_change
650 attribute with days since the Epoch after a password change
651 operation.
652 Default: False
654 ldap_access_filter (string)
656 If using access_provider = ldap and ldap_access_order = filter
657 (default), this option is mandatory. It specifies an LDAP search
658 filter criteria that must be met for the user to be granted access
659 on this host. If access_provider = ldap, ldap_access_order = filter
660 and this option is not set, it will result in all users being
661 denied access. Use access_provider = permit to change this default
662 behavior. Please note that this filter is applied on the LDAP user
663 entry only and thus filtering based on nested groups may not work
664 (e.g. memberOf attribute on AD entries points only to direct
665 parents). If filtering based on nested groups is required, please
666 see sssd-simple(5).
667 Example:
669 access_provider = ldap
671 ldap_access_filter = (employeeType=admin)
672 This example means that access to this host is restricted to users
675 whose employeeType attribute is set to "admin".
676 Offline caching for this feature is limited to determining whether
678 the user's last online login was granted access permission. If they
679 were granted access during their last login, they will continue to
680 be granted access while offline and vice versa.
681 Default: Empty
683 ldap_account_expire_policy (string)
685 With this option a client side evaluation of access control
686 attributes can be enabled.
687 Please note that it is always recommended to use server side access
689 control, i.e. the LDAP server should deny the bind request with a
690 suitable error code even if the password is correct.
691 The following values are allowed:
693 shadow: use the value of ldap_user_shadow_expire to determine if
695 the account is expired.
696 ad: use the value of the 32bit field
698 ldap_user_ad_user_account_control and allow access if the second
699 bit is not set. If the attribute is missing access is granted. Also
700 the expiration time of the account is checked.
701 rhds, ipa, 389ds: use the value of ldap_ns_account_lock to check if
703 access is allowed or not.
704 nds: the values of ldap_user_nds_login_allowed_time_map,
706 ldap_user_nds_login_disabled and
707 ldap_user_nds_login_expiration_time are used to check if access is
708 allowed. If both attributes are missing access is granted.
709 This is an experimental feature, please use
710 https://github.com/SSSD/sssd/ to report any issues.
711 Please note that the ldap_access_order configuration option must
713 include “expire” in order for the ldap_account_expire_policy option
714 to work.
715 Default: Empty
717 ldap_access_order (string)
719 Comma separated list of access control options. Allowed values are:
720 filter: use ldap_access_filter
722 lockout: use account locking. If set, this option denies access in
724 case that ldap attribute 'pwdAccountLockedTime' is present and has
725 value of '000001010000Z'. Please see the option ldap_pwdlockout_dn.
726 Please note that 'access_provider = ldap' must be set for this
727 feature to work.
728 Please note that this option is superseded by the “ppolicy” option
730 and might be removed in a future release.
731 ppolicy: use account locking. If set, this option denies access in
733 case that ldap attribute 'pwdAccountLockedTime' is present and has
734 value of '000001010000Z' or represents any time in the past. The
735 value of the 'pwdAccountLockedTime' attribute must end with 'Z',
736 which denotes the UTC time zone. Other time zones are not currently
737 supported and will result in "access-denied" when users attempt to
738 log in. Please see the option ldap_pwdlockout_dn. Please note that
739 'access_provider = ldap' must be set for this feature to work.
740 expire: use ldap_account_expire_policy
742 pwd_expire_policy_reject, pwd_expire_policy_warn,
744 pwd_expire_policy_renew: These options are useful if users are
745 interested in being warned that password is about to expire and
746 authentication is based on using a different method than passwords
747 - for example SSH keys.
748 The difference between these options is the action taken if user
750 password is expired: pwd_expire_policy_reject - user is denied to
751 log in, pwd_expire_policy_warn - user is still able to log in,
752 pwd_expire_policy_renew - user is prompted to change his password
753 immediately.
754 Note If user password is expired no explicit message is prompted by
756 SSSD.
757 Please note that 'access_provider = ldap' must be set for this
759 feature to work. Also 'ldap_pwd_policy' must be set to an
760 appropriate password policy.
761 authorized_service: use the authorizedService attribute to
763 determine access
764 host: use the host attribute to determine access
766 rhost: use the rhost attribute to determine whether remote host can
768 access
769 Please note, rhost field in pam is set by application, it is better
771 to check what the application sends to pam, before enabling this
772 access control option
773 Default: filter
775 Please note that it is a configuration error if a value is used
777 more than once.
778 ldap_pwdlockout_dn (string)
780 This option specifies the DN of password policy entry on LDAP
781 server. Please note that absence of this option in sssd.conf in
782 case of enabled account lockout checking will yield access denied
783 as ppolicy attributes on LDAP server cannot be checked properly.
784 Example: cn=ppolicy,ou=policies,dc=example,dc=com
786 Default: cn=ppolicy,ou=policies,$ldap_search_base
788 ldap_deref (string)
790 Specifies how alias dereferencing is done when performing a search.
791 The following options are allowed:
792 never: Aliases are never dereferenced.
794 searching: Aliases are dereferenced in subordinates of the base
796 object, but not in locating the base object of the search.
797 finding: Aliases are only dereferenced when locating the base
799 object of the search.
800 always: Aliases are dereferenced both in searching and in locating
802 the base object of the search.
803 Default: Empty (this is handled as never by the LDAP client
805 libraries)
806 ldap_rfc2307_fallback_to_local_users (boolean)
808 Allows to retain local users as members of an LDAP group for
809 servers that use the RFC2307 schema.
810 In some environments where the RFC2307 schema is used, local users
812 are made members of LDAP groups by adding their names to the
813 memberUid attribute. The self-consistency of the domain is
814 compromised when this is done, so SSSD would normally remove the
815 "missing" users from the cached group memberships as soon as
816 nsswitch tries to fetch information about the user via getpw*() or
817 initgroups() calls.
818 This option falls back to checking if local users are referenced,
820 and caches them so that later initgroups() calls will augment the
821 local users with the additional LDAP groups.
822 Default: false
824 wildcard_limit (integer)
826 Specifies an upper limit on the number of entries that are
827 downloaded during a wildcard lookup.
828 At the moment, only the InfoPipe responder supports wildcard
830 lookups.
831 Default: 1000 (often the size of one page)
833 ldap_library_debug_level (integer)
835 Switches on libldap debugging with the given level. The libldap
836 debug messages will be written independent of the general
837 debug_level.
838 OpenLDAP uses a bitmap to enable debugging for specific components,
840 -1 will enable full debug output.
841 Default: 0 (libldap debugging disabled)
843
845 The detailed instructions for configuration of sudo_provider are in the
846 manual page sssd-sudo(5).
847 ldap_sudo_full_refresh_interval (integer)
849 How many seconds SSSD will wait between executing a full refresh of
850 sudo rules (which downloads all rules that are stored on the
851 server).
852 The value must be greater than ldap_sudo_smart_refresh_interval
854 Default: 21600 (6 hours)
856 ldap_sudo_smart_refresh_interval (integer)
858 How many seconds SSSD has to wait before executing a smart refresh
859 of sudo rules (which downloads all rules that have USN higher than
860 the highest server USN value that is currently known by SSSD).
861 If USN attributes are not supported by the server, the
863 modifyTimestamp attribute is used instead.
864 Note: the highest USN value can be updated by three tasks: 1) By
866 sudo full and smart refresh (if updated rules are found), 2) by
867 enumeration of users and groups (if enabled and updated users or
868 groups are found) and 3) by reconnecting to the server (by default
869 every 15 minutes, see ldap_connection_expire_timeout).
870 Default: 900 (15 minutes)
872 ldap_sudo_use_host_filter (boolean)
874 If true, SSSD will download only rules that are applicable to this
875 machine (using the IPv4 or IPv6 host/network addresses and
876 hostnames).
877 Default: true
879 ldap_sudo_hostnames (string)
881 Space separated list of hostnames or fully qualified domain names
882 that should be used to filter the rules.
883 If this option is empty, SSSD will try to discover the hostname and
885 the fully qualified domain name automatically.
886 If ldap_sudo_use_host_filter is false then this option has no
888 effect.
889 Default: not specified
891 ldap_sudo_ip (string)
893 Space separated list of IPv4 or IPv6 host/network addresses that
894 should be used to filter the rules.
895 If this option is empty, SSSD will try to discover the addresses
897 automatically.
898 If ldap_sudo_use_host_filter is false then this option has no
900 effect.
901 Default: not specified
903 ldap_sudo_include_netgroups (boolean)
905 If true then SSSD will download every rule that contains a netgroup
906 in sudoHost attribute.
907 If ldap_sudo_use_host_filter is false then this option has no
909 effect.
910 Default: true
912 ldap_sudo_include_regexp (boolean)
914 If true then SSSD will download every rule that contains a wildcard
915 in sudoHost attribute.
916 If ldap_sudo_use_host_filter is false then this option has no
918 effect.
919 Note
921 Using wildcard is an operation that is very costly to evaluate
922 on the LDAP server side!
923 Default: false
924 This manual page only describes attribute name mapping. For detailed
926 explanation of sudo related attribute semantics, see sudoers.ldap(5)
927
929 Some of the defaults for the parameters below are dependent on the LDAP
930 schema.
931 ldap_autofs_map_master_name (string)
933 The name of the automount master map in LDAP.
934 Default: auto.master
936 ldap_autofs_map_object_class (string)
938 The object class of an automount map entry in LDAP.
939 Default: nisMap (rfc2307, autofs_provider=ad), otherwise
941 automountMap
942 ldap_autofs_map_name (string)
944 The name of an automount map entry in LDAP.
945 Default: nisMapName (rfc2307, autofs_provider=ad), otherwise
947 automountMapName
948 ldap_autofs_entry_object_class (string)
950 The object class of an automount entry in LDAP. The entry usually
951 corresponds to a mount point.
952 Default: nisObject (rfc2307, autofs_provider=ad), otherwise
954 automount
955 ldap_autofs_entry_key (string)
957 The key of an automount entry in LDAP. The entry usually
958 corresponds to a mount point.
959 Default: cn (rfc2307, autofs_provider=ad), otherwise automountKey
961 ldap_autofs_entry_value (string)
963 The key of an automount entry in LDAP. The entry usually
964 corresponds to a mount point.
965 Default: nisMapEntry (rfc2307, autofs_provider=ad), otherwise
967 automountInformation
968 Please note that the automounter only reads the master map on startup,
970 so if any autofs-related changes are made to the sssd.conf, you
971 typically also need to restart the automounter daemon after restarting
972 the SSSD.
973
975 These options are supported by LDAP domains, but they should be used
976 with caution. Please include them in your configuration only if you
977 know what you are doing.
978 ldap_netgroup_search_base (string)
980 An optional base DN, search scope and LDAP filter to restrict LDAP
981 searches for this attribute type.
982 syntax:
984 search_base[?scope?[filter][?search_base?scope?[filter]]*]
986 The scope can be one of "base", "onelevel" or "subtree". The scope
988 functions as specified in section 4.5.1.2 of
989 http://tools.ietf.org/html/rfc4511
990 The filter must be a valid LDAP search filter as specified by
992 http://www.ietf.org/rfc/rfc2254.txt
993 For examples of this syntax, please refer to the “ldap_search_base”
995 examples section.
996 Default: the value of ldap_search_base
998 Please note that specifying scope or filter is not supported for
1000 searches against an Active Directory Server that might yield a
1001 large number of results and trigger the Range Retrieval extension
1002 in the response.
1003 ldap_user_search_base (string)
1005 An optional base DN, search scope and LDAP filter to restrict LDAP
1006 searches for this attribute type.
1007 syntax:
1009 search_base[?scope?[filter][?search_base?scope?[filter]]*]
1011 The scope can be one of "base", "onelevel" or "subtree". The scope
1013 functions as specified in section 4.5.1.2 of
1014 http://tools.ietf.org/html/rfc4511
1015 The filter must be a valid LDAP search filter as specified by
1017 http://www.ietf.org/rfc/rfc2254.txt
1018 For examples of this syntax, please refer to the “ldap_search_base”
1020 examples section.
1021 Default: the value of ldap_search_base
1023 Please note that specifying scope or filter is not supported for
1025 searches against an Active Directory Server that might yield a
1026 large number of results and trigger the Range Retrieval extension
1027 in the response.
1028 ldap_group_search_base (string)
1030 An optional base DN, search scope and LDAP filter to restrict LDAP
1031 searches for this attribute type.
1032 syntax:
1034 search_base[?scope?[filter][?search_base?scope?[filter]]*]
1036 The scope can be one of "base", "onelevel" or "subtree". The scope
1038 functions as specified in section 4.5.1.2 of
1039 http://tools.ietf.org/html/rfc4511
1040 The filter must be a valid LDAP search filter as specified by
1042 http://www.ietf.org/rfc/rfc2254.txt
1043 For examples of this syntax, please refer to the “ldap_search_base”
1045 examples section.
1046 Default: the value of ldap_search_base
1048 Please note that specifying scope or filter is not supported for
1050 searches against an Active Directory Server that might yield a
1051 large number of results and trigger the Range Retrieval extension
1052 in the response.
1053 Note
1055 If the option “ldap_use_tokengroups” is enabled, the searches
1056 against Active Directory will not be restricted and return all
1057 groups memberships, even with no GID mapping. It is recommended to
1058 disable this feature, if group names are not being displayed
1059 correctly.
1060 ldap_sudo_search_base (string)
1062 An optional base DN, search scope and LDAP filter to restrict LDAP
1063 searches for this attribute type.
1064 syntax:
1066 search_base[?scope?[filter][?search_base?scope?[filter]]*]
1068 The scope can be one of "base", "onelevel" or "subtree". The scope
1070 functions as specified in section 4.5.1.2 of
1071 http://tools.ietf.org/html/rfc4511
1072 The filter must be a valid LDAP search filter as specified by
1074 http://www.ietf.org/rfc/rfc2254.txt
1075 For examples of this syntax, please refer to the “ldap_search_base”
1077 examples section.
1078 Default: the value of ldap_search_base
1080 Please note that specifying scope or filter is not supported for
1082 searches against an Active Directory Server that might yield a
1083 large number of results and trigger the Range Retrieval extension
1084 in the response.
1085 ldap_autofs_search_base (string)
1087 An optional base DN, search scope and LDAP filter to restrict LDAP
1088 searches for this attribute type.
1089 syntax:
1091 search_base[?scope?[filter][?search_base?scope?[filter]]*]
1093 The scope can be one of "base", "onelevel" or "subtree". The scope
1095 functions as specified in section 4.5.1.2 of
1096 http://tools.ietf.org/html/rfc4511
1097 The filter must be a valid LDAP search filter as specified by
1099 http://www.ietf.org/rfc/rfc2254.txt
1100 For examples of this syntax, please refer to the “ldap_search_base”
1102 examples section.
1103 Default: the value of ldap_search_base
1105 Please note that specifying scope or filter is not supported for
1107 searches against an Active Directory Server that might yield a
1108 large number of results and trigger the Range Retrieval extension
1109 in the response.
1110
1112 The failover feature allows back ends to automatically switch to a
1113 different server if the current server fails.
1114 Failover Syntax
1116 The list of servers is given as a comma-separated list; any number of
1117 spaces is allowed around the comma. The servers are listed in order of
1118 preference. The list can contain any number of servers.
1119 For each failover-enabled config option, two variants exist: primary
1121 and backup. The idea is that servers in the primary list are preferred
1122 and backup servers are only searched if no primary servers can be
1123 reached. If a backup server is selected, a timeout of 31 seconds is
1124 set. After this timeout SSSD will periodically try to reconnect to one
1125 of the primary servers. If it succeeds, it will replace the current
1126 active (backup) server.
1127 The Failover Mechanism
1129 The failover mechanism distinguishes between a machine and a service.
1130 The back end first tries to resolve the hostname of a given machine; if
1131 this resolution attempt fails, the machine is considered offline. No
1132 further attempts are made to connect to this machine for any other
1133 service. If the resolution attempt succeeds, the back end tries to
1134 connect to a service on this machine. If the service connection attempt
1135 fails, then only this particular service is considered offline and the
1136 back end automatically switches over to the next service. The machine
1137 is still considered online and might still be tried for another
1138 service.
1139 Further connection attempts are made to machines or services marked as
1141 offline after a specified period of time; this is currently hard coded
1142 to 30 seconds.
1143 If there are no more machines to try, the back end as a whole switches
1145 to offline mode, and then attempts to reconnect every 30 seconds.
1146 Failover time outs and tuning
1148 Resolving a server to connect to can be as simple as running a single
1149 DNS query or can involve several steps, such as finding the correct
1150 site or trying out multiple host names in case some of the configured
1151 servers are not reachable. The more complex scenarios can take some
1152 time and SSSD needs to balance between providing enough time to finish
1153 the resolution process but on the other hand, not trying for too long
1154 before falling back to offline mode. If the SSSD debug logs show that
1155 the server resolution is timing out before a live server is contacted,
1156 you can consider changing the time outs.
1157 This section lists the available tunables. Please refer to their
1159 description in the sssd.conf(5), manual page.
1160 dns_resolver_server_timeout
1162 Time in milliseconds that sets how long would SSSD talk to a single
1163 DNS server before trying next one.
1164 Default: 1000
1166 dns_resolver_op_timeout
1168 Time in seconds to tell how long would SSSD try to resolve single
1169 DNS query (e.g. resolution of a hostname or an SRV record) before
1170 trying the next hostname or discovery domain.
1171 Default: 3
1173 dns_resolver_timeout
1175 How long would SSSD try to resolve a failover service. This service
1176 resolution internally might include several steps, such as
1177 resolving DNS SRV queries or locating the site.
1178 Default: 6
1180 For LDAP-based providers, the resolve operation is performed as part of
1182 an LDAP connection operation. Therefore, also the “ldap_opt_timeout”
1183 timeout should be set to a larger value than “dns_resolver_timeout”
1184 which in turn should be set to a larger value than
1185 “dns_resolver_op_timeout” which should be larger than
1186 “dns_resolver_server_timeout”.
1187
1189 The service discovery feature allows back ends to automatically find
1190 the appropriate servers to connect to using a special DNS query. This
1191 feature is not supported for backup servers.
1192 Configuration
1194 If no servers are specified, the back end automatically uses service
1195 discovery to try to find a server. Optionally, the user may choose to
1196 use both fixed server addresses and service discovery by inserting a
1197 special keyword, “_srv_”, in the list of servers. The order of
1198 preference is maintained. This feature is useful if, for example, the
1199 user prefers to use service discovery whenever possible, and fall back
1200 to a specific server when no servers can be discovered using DNS.
1201 The domain name
1203 Please refer to the “dns_discovery_domain” parameter in the
1204 sssd.conf(5) manual page for more details.
1205 The protocol
1207 The queries usually specify _tcp as the protocol. Exceptions are
1208 documented in respective option description.
1209 See Also
1211 For more information on the service discovery mechanism, refer to RFC
1212 2782.
1213
1215 The ID-mapping feature allows SSSD to act as a client of Active
1216 Directory without requiring administrators to extend user attributes to
1217 support POSIX attributes for user and group identifiers.
1218 NOTE: When ID-mapping is enabled, the uidNumber and gidNumber
1220 attributes are ignored. This is to avoid the possibility of conflicts
1221 between automatically-assigned and manually-assigned values. If you
1222 need to use manually-assigned values, ALL values must be
1223 manually-assigned.
1224 Please note that changing the ID mapping related configuration options
1226 will cause user and group IDs to change. At the moment, SSSD does not
1227 support changing IDs, so the SSSD database must be removed. Because
1228 cached passwords are also stored in the database, removing the database
1229 should only be performed while the authentication servers are
1230 reachable, otherwise users might get locked out. In order to cache the
1231 password, an authentication must be performed. It is not sufficient to
1232 use sss_cache(8) to remove the database, rather the process consists
1233 of:
1234 · Making sure the remote servers are reachable
1236 · Stopping the SSSD service
1238 · Removing the database
1240 · Starting the SSSD service
1242 Moreover, as the change of IDs might necessitate the adjustment of
1244 other system properties such as file and directory ownership, it's
1245 advisable to plan ahead and test the ID mapping configuration
1246 thoroughly.
1247 Mapping Algorithm
1249 Active Directory provides an objectSID for every user and group object
1250 in the directory. This objectSID can be broken up into components that
1251 represent the Active Directory domain identity and the relative
1252 identifier (RID) of the user or group object.
1253 The SSSD ID-mapping algorithm takes a range of available UIDs and
1255 divides it into equally-sized component sections - called "slices"-.
1256 Each slice represents the space available to an Active Directory
1257 domain.
1258 When a user or group entry for a particular domain is encountered for
1260 the first time, the SSSD allocates one of the available slices for that
1261 domain. In order to make this slice-assignment repeatable on different
1262 client machines, we select the slice based on the following algorithm:
1263 The SID string is passed through the murmurhash3 algorithm to convert
1265 it to a 32-bit hashed value. We then take the modulus of this value
1266 with the total number of available slices to pick the slice.
1267 NOTE: It is possible to encounter collisions in the hash and subsequent
1269 modulus. In these situations, we will select the next available slice,
1270 but it may not be possible to reproduce the same exact set of slices on
1271 other machines (since the order that they are encountered will
1272 determine their slice). In this situation, it is recommended to either
1273 switch to using explicit POSIX attributes in Active Directory
1274 (disabling ID-mapping) or configure a default domain to guarantee that
1275 at least one is always consistent. See “Configuration” for details.
1276 Configuration
1278 Minimum configuration (in the “[domain/DOMAINNAME]” section):
1279 ldap_id_mapping = True
1281 ldap_schema = ad
1282 The default configuration results in configuring 10,000 slices, each
1284 capable of holding up to 200,000 IDs, starting from 200,000 and going
1285 up to 2,000,200,000. This should be sufficient for most deployments.
1286 Advanced Configuration
1288 ldap_idmap_range_min (integer)
1289 Specifies the lower bound of the range of POSIX IDs to use for
1290 mapping Active Directory user and group SIDs.
1291 NOTE: This option is different from “min_id” in that “min_id”
1293 acts to filter the output of requests to this domain, whereas
1294 this option controls the range of ID assignment. This is a
1295 subtle distinction, but the good general advice would be to
1296 have “min_id” be less-than or equal to “ldap_idmap_range_min”
1297 Default: 200000
1299 ldap_idmap_range_max (integer)
1301 Specifies the upper bound of the range of POSIX IDs to use for
1302 mapping Active Directory user and group SIDs.
1303 NOTE: This option is different from “max_id” in that “max_id”
1305 acts to filter the output of requests to this domain, whereas
1306 this option controls the range of ID assignment. This is a
1307 subtle distinction, but the good general advice would be to
1308 have “max_id” be greater-than or equal to
1309 “ldap_idmap_range_max”
1310 Default: 2000200000
1312 ldap_idmap_range_size (integer)
1314 Specifies the number of IDs available for each slice. If the
1315 range size does not divide evenly into the min and max values,
1316 it will create as many complete slices as it can.
1317 NOTE: The value of this option must be at least as large as the
1319 highest user RID planned for use on the Active Directory
1320 server. User lookups and login will fail for any user whose RID
1321 is greater than this value.
1322 For example, if your most recently-added Active Directory user
1324 has objectSid=S-1-5-21-2153326666-2176343378-3404031434-1107,
1325 “ldap_idmap_range_size” must be at least 1108 as range size is
1326 equal to maximal SID minus minimal SID plus one (e.g. 1108 =
1327 1107 - 0 + 1).
1328 It is important to plan ahead for future expansion, as changing
1330 this value will result in changing all of the ID mappings on
1331 the system, leading to users with different local IDs than they
1332 previously had.
1333 Default: 200000
1335 ldap_idmap_default_domain_sid (string)
1337 Specify the domain SID of the default domain. This will
1338 guarantee that this domain will always be assigned to slice
1339 zero in the ID map, bypassing the murmurhash algorithm
1340 described above.
1341 Default: not set
1343 ldap_idmap_default_domain (string)
1345 Specify the name of the default domain.
1346 Default: not set
1348 ldap_idmap_autorid_compat (boolean)
1350 Changes the behavior of the ID-mapping algorithm to behave more
1351 similarly to winbind's “idmap_autorid” algorithm.
1352 When this option is configured, domains will be allocated
1354 starting with slice zero and increasing monatomically with each
1355 additional domain.
1356 NOTE: This algorithm is non-deterministic (it depends on the
1358 order that users and groups are requested). If this mode is
1359 required for compatibility with machines running winbind, it is
1360 recommended to also use the “ldap_idmap_default_domain_sid”
1361 option to guarantee that at least one domain is consistently
1362 allocated to slice zero.
1363 Default: False
1365 ldap_idmap_helper_table_size (integer)
1367 Maximal number of secondary slices that is tried when
1368 performing mapping from UNIX id to SID.
1369 Note: Additional secondary slices might be generated when SID
1371 is being mapped to UNIX id and RID part of SID is out of range
1372 for secondary slices generated so far. If value of
1373 ldap_idmap_helper_table_size is equal to 0 then no additional
1374 secondary slices are generated.
1375 Default: 10
1377 Well-Known SIDs
1379 SSSD supports to look up the names of Well-Known SIDs, i.e. SIDs with a
1380 special hardcoded meaning. Since the generic users and groups related
1381 to those Well-Known SIDs have no equivalent in a Linux/UNIX environment
1382 no POSIX IDs are available for those objects.
1383 The SID name space is organized in authorities which can be seen as
1385 different domains. The authorities for the Well-Known SIDs are
1386 · Null Authority
1388 · World Authority
1390 · Local Authority
1392 · Creator Authority
1394 · NT Authority
1396 · Built-in
1398 The capitalized version of these names are used as domain names when
1400 returning the fully qualified name of a Well-Known SID.
1401 Since some utilities allow to modify SID based access control
1403 information with the help of a name instead of using the SID directly
1404 SSSD supports to look up the SID by the name as well. To avoid
1405 collisions only the fully qualified names can be used to look up
1406 Well-Known SIDs. As a result the domain names “NULL AUTHORITY”, “WORLD
1407 AUTHORITY”, “ LOCAL AUTHORITY”, “CREATOR AUTHORITY”, “NT AUTHORITY” and
1408 “BUILTIN” should not be used as domain names in sssd.conf.
1409
1411 The following example assumes that SSSD is correctly configured and
1412 LDAP is set to one of the domains in the [domains] section.
1413 [domain/LDAP]
1415 id_provider = ldap
1416 auth_provider = ldap
1417 ldap_uri = ldap://ldap.mydomain.org
1418 ldap_search_base = dc=mydomain,dc=org
1419 ldap_tls_reqcert = demand
1420 cache_credentials = true
1421
1424 The following example assumes that SSSD is correctly configured and to
1425 use the ldap_access_order=lockout.
1426 [domain/LDAP]
1428 id_provider = ldap
1429 auth_provider = ldap
1430 access_provider = ldap
1431 ldap_access_order = lockout
1432 ldap_pwdlockout_dn = cn=ppolicy,ou=policies,dc=mydomain,dc=org
1433 ldap_uri = ldap://ldap.mydomain.org
1434 ldap_search_base = dc=mydomain,dc=org
1435 ldap_tls_reqcert = demand
1436 cache_credentials = true
1437
1440 The descriptions of some of the configuration options in this manual
1441 page are based on the ldap.conf(5) manual page from the OpenLDAP 2.4
1442 distribution.
1443
1445 sssd(8), sssd.conf(5), sssd-ldap(5), sssd-krb5(5), sssd-simple(5),
1446 sssd-ipa(5), sssd-ad(5), sssd-files(5), sssd-sudo(5), sssd-session-
1447 recording(5), sss_cache(8), sss_debuglevel(8), sss_obfuscate(8),
1448 sss_seed(8), sssd_krb5_locator_plugin(8), sss_ssh_authorizedkeys(8),
1449 sss_ssh_knownhostsproxy(8), sssd-ifp(5), pam_sss(8). sss_rpcidmapd(5)
1450 sssd-systemtap(5)
1451
1453 The SSSD upstream - https://github.com/SSSD/sssd/
1454SSSD 02/19/2021 SSSD-LDAP(5)