30.4. Creating Domains
SSSD recognizes domains, which are associated with the different identity servers. Domains are a combination of an identity provider and an authentication method. SSSD works with LDAP identity providers (including OpenLDAP, Red Hat Directory Server, and Microsoft Active Directory) and can use native LDAP authentication or Kerberos authentication.
As long as they belong to different domains, SSSD can recognize different users with the same username. For example, SSSD can successfully authenticate both
jsmith
in the ldap.example.com
domain and jsmith
in the ldap.otherexample.com
domain. SSSD allows requests using fully-qualified domain names, so requesting information for jsmith@ldap.example.com
returns the proper user account. Specifying only the username returns the user for whichever domain comes first in the lookup order.
Note
SSSD has a
filter_users
option, which excludes the specified users from being returned in a search.
Configuring a domain defines both where user information is stored and how those users are allowed to authenticate to the system. The possible combinations are listed in Table 30.3, “Identity Store and Authentication Type Combinations”.
Identification Provider | Authentication Provider |
---|---|
LDAP | LDAP |
LDAP | Kerberos |
proxy | LDAP |
proxy | Kerberos |
proxy | proxy |
30.4.1. General Rules and Options for Configuring a Domain
A domain configuration defines the identity provider, the authentication provider, and any specific configuration to access the information in those providers. There are two types of identity providers — LDAP and proxy —three types of authentication providers — LDAP, Kerberos, and proxy. The identity and authentication providers can be configured in any combination in a domain entry.
Along with the domain entry itself, the domain name must be added to the list of domains that SSSD will query. For example:
domains = LOCAL,Name [domain/Name] id_provider = type auth_provider = type provider_specific = value global = value
global attributes are available to any type of domain, such as cache and time out settings. Each identity and authentication provider has its own set of required and optional configuration parameters.
Parameter | Value Format | Description |
---|---|---|
id_provider | string | Specifies the data provider identity backend to use for this domain. The supported identity backends are:
|
auth_provider | string | Sets the authentication provider used for the domain. The default value for this option is the value of id_provider . The supported authentication providers are ldap, ipa, krb5 (Kerberos), proxy, and none. |
min_id,max_id | integer | Optional. Specifies the UID and GID range for the domain. If a domain contains entries that are outside that range, they are ignored. The default value for min_id is 1 ; the default value for max_id is 0 , which is unlimited.
Important
The default min_id value is the same for all types of identity provider. If LDAP directories are using UID numbers that start at one, it could cause conflicts with users in the local /etc/passwd file. To avoid these conflicts, set min_id to 1000 or higher as possible.
|
enumerate | Boolean | Optional. Specifies whether to list the users and groups of a domain. Enumeration means that the entire set of available users and groups on the remote source is cached on the local machine. When enumeration is disabled, users and groups are only cached as they are requested.
Warning
When enumeration is enabled, reinitializing a client results in a complete refresh of the entire set of available users and groups from the remote source. Similarly, when SSSD is connected to a new server, the entire set of available users and groups from the remote source is pulled and cached on the local machine. In a domain with a large number of clients connected to a remote source, this refresh process can harm the network performance because of frequent queries from the clients. If the set of available users and groups is large enough, it degrades client performance as well.
false , which disables enumeration. |
cache_credentials | Boolean | Optional. Specifies whether to store user credentials in the local SSSD domain database cache. The default value for this parameter is false . Set this value to true for domains other than the LOCAL domain to enable offline authentication. |
entry_cache_timeout | integer | Optional. Specifies how long, in seconds, SSSD should cache positive cache hits. A positive cache hit is a successful query. |
use_fully_qualified_names | Boolean | Optional. Specifies whether requests to this domain require fully-qualified domain names. If set to true , all requests to this domain must use fully-qualified domain names. It also means that the output from the request displays the fully-qualified name. Restricting requests to fully-qualified user names allows SSSD to differentiate between domains with users with conflicting usernames.
If
use_fully_qualified_names is set to false , it is possible to use the fully-qualified name in the requests, but only the simplified version is displayed in the output.
SSSD can only parse names based on the domain name, not the realm name. The same name can be used for both domains and realms, however.
|