SSSD Manual pages
sssd-ad
5
File Formats and Conventions
sssd-ad
SSSD Active Directory provider
DESCRIPTION
This manual page describes the configuration of the AD provider
for
sssd
8
.
For a detailed syntax reference, refer to the FILE FORMAT
section of the
sssd.conf
5
manual page.
The AD provider is a back end used to connect to an Active
Directory server. This provider requires that the machine be
joined to the AD domain and a keytab is available.
The AD provider supports connecting to Active Directory 2008 R2
or later. Earlier versions may work, but are unsupported.
The AD provider is able to provide identity information and
authentication for entities from trusted domains as well. Currently
only trusted domains in the same forest are recognized.
The AD provider accepts the same options used by the
sssd-ldap
5
identity provider and the
sssd-krb5
5
authentication provider with some exceptions described
below.
However, it is neither necessary nor recommended to set these
options. The AD provider can also be used as an access and chpass
provider. No configuration of the access provider is required on
the client side.
By default, the AD provider will map UID and GID values from the
objectSID parameter in Active Directory. For details on this, see
the ID MAPPING
section below. If you want to
disable ID mapping and instead rely on POSIX attributes defined in
Active Directory, you should set
ldap_id_mapping = False
In order to retrieve users and groups using POSIX attributes from trusted
domains, the AD administrator must make sure that the POSIX attributes
are replicated to the Global Catalog.
Users, groups and other entities served by SSSD are always treated as
case-insensitive in the AD provider for compatibility with Active
Directory's LDAP implementation.
CONFIGURATION OPTIONS
Refer to the section DOMAIN SECTIONS
of the
sssd.conf
5
manual page for details on the configuration of an SSSD domain.
ad_domain (string)
Specifies the name of the Active Directory domain.
This is optional. If not provided, the
configuration domain name is used.
For proper operation, this option should be
specified as the lower-case version of the long
version of the Active Directory domain.
The short domain name (also known as the NetBIOS
or the flat name) is autodetected by the SSSD.
ad_server, ad_backup_server (string)
The comma-separated list of
hostnames of the AD servers to which SSSD should
connect in order of preference. For more
information on failover and server redundancy, see
the FAILOVER
section.
This is optional if autodiscovery is enabled.
For more information on service discovery, refer
to the SERVICE DISCOVERY
section.
ad_hostname (string)
Optional. May be set on machines where the
hostname(5) does not reflect the fully qualified
name used in the Active Directory domain to
identify this host.
This field is used to determine the host principal
in use in the keytab. It must match the hostname
for which the keytab was issued.
ad_enable_dns_sites (boolean)
Enables DNS sites - location based
service discovery.
If true and service discovery (see Service
Discovery paragraph at the bottom of the man page)
is enabled, the SSSD will first attempt to discover
the Active Directory server to connect to using the
Active Directory Site Discovery and fall back to
the DNS SRV records if no AD site is found. The
DNS SRV configuration, including the discovery
domain, is used during site discovery as well.
Default: true
ad_access_filter (boolean)
This option specifies LDAP access control
filter that the user must match in order
to be allowed access. Please note that the
access_filter
option must be
explicitly set to ad
in order
for this option to have an effect.
The option also supports specifying different
filters per domain or forest. This
extended filter would consist of:
KEYWORD:NAME:FILTER
.
The keyword can be either DOM
,
FOREST
or missing.
If the keyword equals to DOM
or is missing, then NAME
specifies
the domain or subdomain the filter applies to.
If the keyword equals to FOREST
,
then the filter equals to all domains from the
forest specified by NAME
.
Multiple filters can be separated with the
?
character, similarly to how
search bases work.
The most specific match is always used. For
example, if the option specified filter
for a domain the user is a member of and a
global filter, the per-domain filter would
be applied. If there are more matches with
the same specification, the first one is used.
Examples:
# apply filter on domain called dom1 only:
dom1:(memberOf=cn=admins,ou=groups,dc=dom1,dc=com)
# apply filter on domain called dom2 only:
DOM:dom2:(memberOf=cn=admins,ou=groups,dc=dom2,dc=com)
# apply filter on forest called EXAMPLE.COM only:
FOREST:EXAMPLE.COM:(memberOf=cn=admins,ou=groups,dc=example,dc=com)
Default: Not set
dyndns_update (boolean)
Optional. This option tells SSSD to automatically
update the Active Directory DNS server with
the IP address of this client. The update is
secured using GSS-TSIG. As a consequence, the
Active Directory administrator only needs to
allow secure updates for the DNS zone. The IP
address of the AD LDAP connection is used for
the updates, if it is not otherwise specified
by using the dyndns_iface
option.
NOTE: On older systems (such as RHEL 5), for this
behavior to work reliably, the default Kerberos
realm must be set properly in /etc/krb5.conf
Default: true
dyndns_ttl (integer)
The TTL to apply to the client DNS record when updating it.
If dyndns_update is false this has no effect. This will
override the TTL serverside if set by an administrator.
Default: 3600 (seconds)
dyndns_iface (string)
Optional. Applicable only when dyndns_update
is true. Choose the interface whose IP address
should be used for dynamic DNS updates.
Default: Use the IP address of the AD LDAP connection
dyndns_refresh_interval (integer)
How often should the back end perform periodic DNS update in
addition to the automatic update performed when the back end
goes online.
This option is optional and applicable only when dyndns_update
is true.
Default: 86400 (24 hours)
dyndns_update_ptr (bool)
Whether the PTR record should also be explicitly
updated when updating the client's DNS records.
Applicable only when dyndns_update is true.
Default: True
dyndns_force_tcp (bool)
Whether the nsupdate utility should default to using
TCP for communicating with the DNS server.
Default: False (let nsupdate choose the protocol)
krb5_use_enterprise_principal (boolean)
Specifies if the user principal should be treated
as enterprise principal. See section 5 of RFC 6806
for more details about enterprise principals.
Default: true
Note that this default differs from the
traditional Kerberos provider back end.
EXAMPLE
The following example assumes that SSSD is correctly
configured and example.com is one of the domains in the
[sssd] section. This example shows only
the AD provider-specific options.
[domain/EXAMPLE]
id_provider = ad
auth_provider = ad
access_provider = ad
chpass_provider = ad
ad_server = dc1.example.com
ad_hostname = client.example.com
ad_domain = example.com
NOTES
The AD access control provider checks if the account is expired.
It has the same effect as the following configuration of the LDAP
provider:
access_provider = ldap
ldap_access_order = expire
ldap_account_expire_policy = ad
However, unless the ad
access control provider
is explicitly configured, the default access provider is
permit
.