SSSD Manual pages
sssd.conf
5
File Formats and Conventions
sssd.conf
the configuration file for SSSD
FILE FORMAT
The file has an ini-style syntax and consists of sections and
parameters. A section begins with the name of the section in
square brackets and continues until the next section begins. An
example of section with single and multi-valued parameters:
[section]
key = value
key2 = value2,value3
The data types used are string (no quotes needed), integer
and bool (with values of TRUE/FALSE
).
A line comment starts with a hash sign (#
) or a
semicolon (;
).
Inline comments are not supported.
All sections can have an optional
description parameter. Its function
is only as a label for the section.
sssd.conf must be a regular file, owned by
root and only root may read from or write to the file.
SPECIAL SECTIONS
The [sssd] section
Individual pieces of SSSD functionality are provided by special
SSSD services that are started and stopped together with SSSD.
The services are managed by a special service frequently called
monitor
. The [sssd]
section is used
to configure the monitor as well as some other important options
like the identity domains.
Section parameters
config_file_version (integer)
Indicates what is the syntax of the config
file. SSSD 0.6.0 and later use version 2.
services
Comma separated list of services that are
started when sssd itself starts.
Supported services: nss, pam
, sudo
, autofs
, ssh
, pac
reconnection_retries (integer)
Number of times services should attempt to
reconnect in the event of a Data Provider
crash or restart before they give up
Default: 3
domains
A domain is a database containing user
information. SSSD can use more domains
at the same time, but at least one
must be configured or SSSD won't start.
This parameter described the list of domains
in the order you want them to be queried.
A domain name should only consist of alphanumeric
ASCII characters, dashes and underscores.
re_expression (string)
Default regular expression that describes how to
parse the string containing user name and domain
into these components.
Each domain can have an individual regular
expression configured. For some ID providers
there are also default regular expressions. See
DOMAIN SECTIONS for more info on these regular
expressions.
full_name_format (string)
The default
printf
3
-compatible format that describes how to
translate a (name, domain) tuple into a fully qualified
name.
Each domain can have an individual format string configured.
see DOMAIN SECTIONS for more info on this option.
try_inotify (boolean)
SSSD monitors the state of resolv.conf to
identify when it needs to update its internal
DNS resolver. By default, we will attempt to
use inotify for this, and will fall back to
polling resolv.conf every five seconds if
inotify cannot be used.
There are some limited situations where it is
preferred that we should skip even trying to
use inotify. In these rare cases, this option
should be set to 'false'
Default: true on platforms where inotify is
supported. False on other platforms.
Note: this option will have no effect on
platforms where inotify is unavailable. On
these platforms, polling will always be used.
krb5_rcache_dir (string)
Directory on the filesystem where SSSD should
store Kerberos replay cache files.
This option accepts a special value
__LIBKRB5_DEFAULTS__ that will instruct SSSD
to let libkrb5 decide the appropriate
location for the replay cache.
Default: Distribution-specific and specified
at build-time. (__LIBKRB5_DEFAULTS__ if not
configured)
default_domain_suffix (string)
This string will be used as a default domain
name for all names without a domain name
component. The main use case is environments
where the primary domain is intended for managing host
policies and all users are located in a trusted domain.
The option allows those users
to log in just with their user name without
giving a domain name as well.
Please note that if this option is set all
users from the primary domain have to use their
fully qualified name, e.g. user@domain.name,
to log in.
Default: not set
SERVICES SECTIONS
Settings that can be used to configure different services
are described in this section. They should reside in the
[$NAME] section, for example,
for NSS service, the section would be [nss]
General service configuration options
These options can be used to configure any service.
debug_level (integer)
debug_timestamps (bool)
Add a timestamp to the debug messages
Default: true
debug_microseconds (bool)
Add microseconds to the timestamp in debug messages
Default: false
timeout (integer)
Timeout in seconds between heartbeats for this
service. This is used to ensure that the process
is alive and capable of answering requests.
Default: 10
reconnection_retries (integer)
Number of times services should attempt to
reconnect in the event of a Data Provider
crash or restart before they give up
Default: 3
fd_limit
This option specifies the maximum number of file
descriptors that may be opened at one time by this
SSSD process. On systems where SSSD is granted the
CAP_SYS_RESOURCE capability, this will be an
absolute setting. On systems without this
capability, the resulting value will be the lower
value of this or the limits.conf "hard" limit.
Default: 8192 (or limits.conf "hard" limit)
client_idle_timeout
This option specifies the number of seconds that
a client of an SSSD process can hold onto a file
descriptor without communicating on it. This value
is limited in order to avoid resource exhaustion
on the system.
Default: 60
force_timeout (integer)
If a service is not responding to ping checks (see
the timeout
option), it is first sent
the SIGTERM signal that instructs it to quit gracefully.
If the service does not terminate after force_timeout
seconds, the monitor will forcibly shut it down by
sending a SIGKILL signal.
Default: 60
NSS configuration options
These options can be used to configure the
Name Service Switch (NSS) service.
enum_cache_timeout (integer)
How many seconds should nss_sss cache enumerations
(requests for info about all users)
Default: 120
entry_cache_nowait_percentage (integer)
The entry cache can be set to automatically update
entries in the background if they are requested
beyond a percentage of the entry_cache_timeout
value for the domain.
For example, if the domain's entry_cache_timeout
is set to 30s and entry_cache_nowait_percentage is
set to 50 (percent), entries that come in after 15
seconds past the last cache update will be
returned immediately, but the SSSD will go and
update the cache on its own, so that future
requests will not need to block waiting for a
cache update.
Valid values for this option are 0-99 and
represent a percentage of the entry_cache_timeout
for each domain. For performance reasons, this
percentage will never reduce the nowait timeout to
less than 10 seconds.
(0 disables this feature)
Default: 50
entry_negative_timeout (integer)
Specifies for how many seconds nss_sss should cache
negative cache hits (that is, queries for
invalid database entries, like nonexistent ones)
before asking the back end again.
Default: 15
filter_users, filter_groups (string)
Exclude certain users from being fetched from the sss
NSS database. This is particularly useful for system
accounts. This option can also be set per-domain or
include fully-qualified names to filter only users from
the particular domain.
Default: root
filter_users_in_groups (bool)
If you want filtered user still be group members
set this option to false.
Default: true
fallback_homedir (string)
Set a default template for a user's home directory
if one is not specified explicitly by the domain's
data provider.
The available values for this option are the same
as for override_homedir.
example:
override_homedir = /home/%u
Default: not set (no substitution for unset home
directories)
override_shell (string)
Override the login shell for all users. This
option can be specified globally in the [nss]
section or per-domain.
Default: not set (SSSD will use the value
retrieved from LDAP)
allowed_shells (string)
Restrict user shell to one of the listed values. The order of evaluation is:
1. If the shell is present in
/etc/shells
, it is used.
2. If the shell is in the allowed_shells list but
not in /etc/shells
, use the
value of the shell_fallback parameter.
3. If the shell is not in the allowed_shells list and
not in /etc/shells
, a nologin shell
is used.
An empty string for shell is passed as-is to libc.
The /etc/shells
is only read on SSSD start up, which means that
a restart of the SSSD is required in case a new shell is installed.
Default: Not set. The user shell is automatically used.
vetoed_shells (string)
Replace any instance of these shells with the shell_fallback
shell_fallback (string)
The default shell to use if an allowed shell is not
installed on the machine.
Default: /bin/sh
default_shell
The default shell to use if the provider does not
return one during lookup. This option supersedes
any other shell options if it takes effect and can
be set either in the [nss] section or per-domain.
Default: not set (Return NULL if no shell is
specified and rely on libc to substitute something
sensible when necessary, usually /bin/sh)
get_domains_timeout (int)
Specifies time in seconds for which the list of
subdomains will be considered valid.
Default: 60
memcache_timeout (int)
Specifies time in seconds for which records
in the in-memory cache will be valid
Default: 300
PAM configuration options
These options can be used to configure the
Pluggable Authentication Module (PAM) service.
offline_credentials_expiration (integer)
If the authentication provider is offline, how
long should we allow cached logins (in days since
the last successful online login).
Default: 0 (No limit)
offline_failed_login_attempts (integer)
If the authentication provider is offline, how
many failed login attempts are allowed.
Default: 0 (No limit)
offline_failed_login_delay (integer)
The time in minutes which has to pass after
offline_failed_login_attempts has been reached
before a new login attempt is possible.
If set to 0 the user cannot authenticate offline if
offline_failed_login_attempts has been reached. Only
a successful online authentication can enable
offline authentication again.
Default: 5
pam_verbosity (integer)
Controls what kind of messages are shown to the user
during authentication. The higher the number to more
messages are displayed.
Currently sssd supports the following values:
0: do not show any message
1: show only important
messages
2: show informational messages
3: show all messages and debug
information
Default: 1
pam_id_timeout (integer)
For any PAM request while SSSD is online, the SSSD will
attempt to immediately update the cached identity
information for the user in order to ensure that
authentication takes place with the latest information.
A complete PAM conversation may perform multiple PAM
requests, such as account management and session
opening. This option controls (on a
per-client-application basis) how long (in seconds) we
can cache the identity information to avoid excessive
round-trips to the identity provider.
Default: 5
pam_pwd_expiration_warning (integer)
Display a warning N days before the password expires.
Please note that the backend server has to provide
information about the expiration time of the password.
If this information is missing, sssd cannot display a
warning.
If zero is set, then this filter is not applied,
i.e. if the expiration warning was received from
backend server, it will automatically be displayed.
This setting can be overridden by setting
pwd_expiration_warning
for a particular domain.
Default: 0
get_domains_timeout (int)
Specifies time in seconds for which the list of
subdomains will be considered valid.
Default: 60
SUDO configuration options
These options can be used to configure the sudo service.
sudo_timed (bool)
Whether or not to evaluate the sudoNotBefore
and sudoNotAfter attributes that implement
time-dependent sudoers entries.
Default: false
AUTOFS configuration options
These options can be used to configure the autofs service.
autofs_negative_timeout (integer)
Specifies for how many seconds should the
autofs responder negative cache hits
(that is, queries for invalid map entries,
like nonexistent ones) before asking the back
end again.
Default: 15
SSH configuration options
These options can be used to configure the SSH service.
ssh_hash_known_hosts (bool)
Whether or not to hash host names and addresses in
the managed known_hosts file.
Default: true
ssh_known_hosts_timeout (integer)
How many seconds to keep a host in the managed
known_hosts file after its host keys were requested.
Default: 180
PAC responder configuration options
The PAC responder works together with the authorization data
plugin for MIT Kerberos sssd_pac_plugin.so and a sub-domain
provider. The plugin sends the PAC data during a GSSAPI
authentication to the PAC responder. The sub-domain provider
collects domain SID and ID ranges of the domain the client is
joined to and of remote trusted domains from the local domain
controller. If the PAC is decoded and evaluated some of the
following operations are done:
If the remote user does not exist in the
cache, it is created. The uid is calculated based on the
SID, trusted domains will have UPGs and the gid will have
the same value as the uid. The home directory is set based
on the subdomain_homedir parameter. The shell will be empty
by default, i.e. the system defaults are used, but can be
overwritten with the default_shell parameter.
If there are SIDs of groups from the domain
the sssd client belongs to, the user will be added to those
groups.
These options can be used to configure the PAC responder.
allowed_uids (string)
Specifies the comma-separated list of UID values or
user names that are allowed to access the PAC
responder. User names are resolved to UIDs at
startup.
Default: 0 (only the root user is allowed to access
the PAC responder)
Please note that although the UID 0 is used as the
default it will be overwritten with this option. If
you still want to allow the root user to access the
PAC responder, which would be the typical case, you
have to add 0 to the list of allowed UIDs as well.
DOMAIN SECTIONS
These configuration options can be present in a domain
configuration section, that is, in a section called
[domain/NAME]
min_id,max_id (integer)
UID and GID limits for the domain. If a domain
contains an entry that is outside these limits, it
is ignored.
For users, this affects the primary GID limit. The
user will not be returned to NSS if either the
UID or the primary GID is outside the range. For
non-primary group memberships, those that are in
range will be reported as expected.
Default: 1 for min_id, 0 (no limit) for max_id
enumerate (bool)
Determines if a domain can be enumerated. This
parameter can have one of the following values:
TRUE = Users and groups are enumerated
FALSE = No enumerations for this domain
Default: FALSE
Note: Enabling enumeration has a moderate
performance impact on SSSD while enumeration
is running. It may take up to several minutes
after SSSD startup to fully complete enumerations.
During this time, individual requests for
information will go directly to LDAP, though it
may be slow, due to the heavy enumeration
processing. Saving a large number of entries
to cache after the enumeration completes might
also be CPU intensive as the memberships have
to be recomputed.
While the first enumeration is running, requests
for the complete user or group lists may return
no results until it completes.
Further, enabling enumeration may increase the time
necessary to detect network disconnection, as
longer timeouts are required to ensure that
enumeration lookups are completed successfully.
For more information, refer to the man pages for
the specific id_provider in use.
For the reasons cited above, enabling enumeration
is not recommended, especially in large
environments.
force_timeout (integer)
If a service is not responding to ping checks (see
the timeout
option), it is first sent
the SIGTERM signal that instructs it to quit gracefully.
If the service does not terminate after force_timeout
seconds, the monitor will forcibly shut it down by
sending a SIGKILL signal.
Default: 60
entry_cache_timeout (integer)
How many seconds should nss_sss consider
entries valid before asking the backend again
Default: 5400
entry_cache_user_timeout (integer)
How many seconds should nss_sss consider
user entries valid before asking the backend again
Default: entry_cache_timeout
entry_cache_group_timeout (integer)
How many seconds should nss_sss consider
group entries valid before asking the backend again
Default: entry_cache_timeout
entry_cache_netgroup_timeout (integer)
How many seconds should nss_sss consider
netgroup entries valid before asking the backend again
Default: entry_cache_timeout
entry_cache_service_timeout (integer)
How many seconds should nss_sss consider
service entries valid before asking the backend again
Default: entry_cache_timeout
entry_cache_sudo_timeout (integer)
How many seconds should sudo consider
rules valid before asking the backend again
Default: entry_cache_timeout
entry_cache_autofs_timeout (integer)
How many seconds should the autofs service
consider automounter maps valid before asking
the backend again
Default: entry_cache_timeout
cache_credentials (bool)
Determines if user credentials are also cached
in the local LDB cache
User credentials are stored in a SHA512 hash, not
in plaintext
Default: FALSE
account_cache_expiration (integer)
Number of days entries are left in cache after
last successful login before being removed during
a cleanup of the cache. 0 means keep forever.
The value of this parameter must be greater than or
equal to offline_credentials_expiration.
Default: 0 (unlimited)
pwd_expiration_warning (integer)
Display a warning N days before the password expires.
If zero is set, then this filter is not applied,
i.e. if the expiration warning was received from
backend server, it will automatically be displayed.
Please note that the backend server has to provide
information about the expiration time of the password.
If this information is missing, sssd cannot display a
warning. Also an auth provider has to be configured for
the backend.
Default: 7 (Kerberos), 0 (LDAP)
id_provider (string)
The identification provider used for the domain.
Supported ID providers are:
proxy
: Support a legacy NSS provider
local
: SSSD internal provider for
local users
ldap
: LDAP provider. See
sssd-ldap
5
for more information on
configuring LDAP.
ipa
: FreeIPA and Red Hat Enterprise
Identity Management provider. See
sssd-ipa
5
for more information on
configuring FreeIPA.
ad
: Active Directory provider. See
sssd-ad
5
for more information on
configuring Active Directory.
use_fully_qualified_names (bool)
Use the full name and domain (as formatted by
the domain's full_name_format) as the user's login
name reported to NSS.
If set to TRUE, all requests to this domain
must use fully qualified names. For example,
if used in LOCAL domain that contains a "test"
user, getent passwd test
wouldn't find the user while getent
passwd test@LOCAL would.
Default: FALSE
ignore_group_members (bool)
Do not return group members for group lookups.
If set to TRUE, the group membership attribute
is not requested from the ldap server, and
group members are not returned when processing
group lookup calls.
Default: FALSE
auth_provider (string)
The authentication provider used for the domain.
Supported auth providers are:
ldap
for native LDAP authentication. See
sssd-ldap
5
for more information on configuring LDAP.
krb5
for Kerberos authentication. See
sssd-krb5
5
for more information on configuring Kerberos.
ipa
: FreeIPA and Red Hat Enterprise
Identity Management provider. See
sssd-ipa
5
for more information on
configuring FreeIPA.
ad
: Active Directory provider. See
sssd-ad
5
for more information on
configuring Active Directory.
proxy
for relaying authentication to some other PAM target.
none
disables authentication explicitly.
Default: id_provider
is used if it
is set and can handle authentication requests.
access_provider (string)
The access control provider used for the domain.
There are two built-in access providers (in
addition to any included in installed backends)
Internal special providers are:
permit
always allow access. It's the only permitted access provider for a local domain.
deny
always deny access.
ldap
for native LDAP authentication. See
sssd-ldap
5
for more information on configuring LDAP.
ipa
: FreeIPA and Red Hat Enterprise
Identity Management provider. See
sssd-ipa
5
for more information on
configuring FreeIPA.
ad
: Active Directory provider. See
sssd-ad
5
for more information on
configuring Active Directory.
simple
access control based on access
or deny lists. See
sssd-simple
5 for more
information on configuring the simple access module.
Default: permit
chpass_provider (string)
The provider which should handle change password
operations for the domain.
Supported change password providers are:
ldap
to change a password stored
in a LDAP server. See
sssd-ldap
5
for more information on configuring LDAP.
krb5
to change the Kerberos
password. See
sssd-krb5
5
for more information on configuring Kerberos.
ipa
: FreeIPA and Red Hat Enterprise
Identity Management provider. See
sssd-ipa
5
for more information on
configuring FreeIPA.
ad
: Active Directory provider. See
sssd-ad
5
for more information on
configuring Active Directory.
proxy
for relaying password changes
to some other PAM target.
none
disallows password changes explicitly.
Default: auth_provider
is used if it
is set and can handle change password requests.
sudo_provider (string)
The SUDO provider used for the domain.
Supported SUDO providers are:
ldap
for rules stored in LDAP. See
sssd-ldap
5
for more information on configuring LDAP.
none
disables SUDO explicitly.
Default: The value of id_provider
is used if it
is set.
selinux_provider (string)
The provider which should handle loading of selinux
settings. Note that this provider will be called right
after access provider ends.
Supported selinux providers are:
ipa
to load selinux settings
from an IPA server. See
sssd-ipa
5
for more information on configuring IPA.
none
disallows fetching selinux settings explicitly.
Default: id_provider
is used if it
is set and can handle selinux loading requests.
subdomains_provider (string)
The provider which should handle fetching of
subdomains. This value should be always the same as
id_provider.
Supported subdomain providers are:
ipa
to load a list of subdomains
from an IPA server. See
sssd-ipa
5
for more information on configuring
IPA.
none
disallows fetching subdomains
explicitly.
Default: The value of id_provider
is
used if it is set.
autofs_provider (string)
The autofs provider used for the domain.
Supported autofs providers are:
ldap
to load maps stored in LDAP. See
sssd-ldap
5
for more information on configuring LDAP.
ipa
to load maps stored in an IPA
server. See
sssd-ipa
5
for more information on configuring IPA.
none
disables autofs explicitly.
Default: The value of id_provider
is used if it
is set.
hostid_provider (string)
The provider used for retrieving host identity information.
Supported hostid providers are:
ipa
to load host identity stored in an IPA
server. See
sssd-ipa
5
for more information on configuring IPA.
none
disables hostid explicitly.
Default: The value of id_provider
is used if it
is set.
re_expression (string)
Regular expression for this domain that describes
how to parse the string containing user name and
domain into these components.
The "domain" can match either the SSSD
configuration domain name, or, in the case
of IPA trust subdomains and Active Directory
domains, the flat (NetBIOS) name of the domain.
Default for the AD and IPA provider:
(((?P<domain>[^\\]+)\\(?P<name>.+$))|((?P<name>[^@]+)@(?P<domain>.+$))|(^(?P<name>[^@\\]+)$))
which allows three different styles for user names:
username
username@domain.name
domain\username
While the first two correspond to the general
default the third one is introduced to allow easy
integration of users from Windows domains.
Default: (?P<name>[^@]+)@?(?P<domain>[^@]*$)
which translates to "the name is everything up to
the @
sign, the domain everything
after that"
PLEASE NOTE: the support for non-unique named
subpatterns is not available on all platforms
(e.g. RHEL5 and SLES10). Only platforms with
libpcre version 7 or higher can support non-unique
named subpatterns.
PLEASE NOTE ALSO: older version of libpcre only
support the Python syntax (?P<name>) to label
subpatterns.
full_name_format (string)
A
printf
3
-compatible format that describes how to
translate a (name, domain) tuple for this domain into a fully
qualified name.
Default: %1$s@%2$s
.
lookup_family_order (string)
Provides the ability to select preferred address family
to use when performing DNS lookups.
Supported values:
ipv4_first: Try looking up IPv4 address, if that fails, try IPv6
ipv4_only: Only attempt to resolve hostnames to IPv4 addresses.
ipv6_first: Try looking up IPv6 address, if that fails, try IPv4
ipv6_only: Only attempt to resolve hostnames to IPv6 addresses.
Default: ipv4_first
dns_resolver_timeout (integer)
Defines the amount of time (in seconds) to wait for a reply from
the DNS resolver before assuming that it is unreachable. If this
timeout is reached, the domain will continue to operate in
offline mode.
Default: 5
dns_discovery_domain (string)
If service discovery is used in the back end, specifies
the domain part of the service discovery DNS query.
Default: Use the domain part of machine's hostname
override_gid (integer)
Override the primary GID value with the one specified.
case_sensitive (boolean)
Treat user and group names as case sensitive. At
the moment, this option is not supported in
the local provider.
Default: True
proxy_fast_alias (boolean)
When a user or group is looked up by name in
the proxy provider, a second lookup by ID is
performed to "canonicalize" the name in case
the requested name was an alias. Setting this
option to true would cause the SSSD to perform
the ID lookup from cache for performance reasons.
Default: false
subdomain_homedir (string)
Use this homedir as default value for all subdomains
within this domain. See override_homedir
for info about possible values. In addition to those, the
expansion below can only be used with
subdomain_homedir.
%F
flat (NetBIOS) name of a subdomain.
The value can be overridden by
override_homedir option.
Default: /home/%d/%u
Options valid for proxy domains.
proxy_pam_target (string)
The proxy target PAM proxies to.
Default: not set by default, you have to take an
existing pam configuration or create a new one and
add the service name here.
proxy_lib_name (string)
The name of the NSS library to use in proxy
domains. The NSS functions searched for in the
library are in the form of
_nss_$(libName)_$(function), for example
_nss_files_getpwent.
The local domain section
This section contains settings for domain that stores users and
groups in SSSD native database, that is, a domain that uses
id_provider=local.
Section parameters
default_shell (string)
The default shell for users created
with SSSD userspace tools.
Default: /bin/bash
base_directory (string)
The tools append the login name to
base_directory and
use that as the home directory.
Default: /home
create_homedir (bool)
Indicate if a home directory should be created by default for new users.
Can be overridden on command line.
Default: TRUE
remove_homedir (bool)
Indicate if a home directory should be removed by default for deleted users.
Can be overridden on command line.
Default: TRUE
homedir_umask (integer)
Used by
sss_useradd
8
to specify the default permissions on a newly created
home directory.
Default: 077
skel_dir (string)
The skeleton directory, which contains files
and directories to be copied in the user's
home directory, when the home directory is
created by
sss_useradd
8
Default: /etc/skel
mail_dir (string)
The mail spool directory. This is needed to
manipulate the mailbox when its corresponding
user account is modified or deleted.
If not specified, a default
value is used.
Default: /var/mail
userdel_cmd (string)
The command that is run after a user is removed.
The command us passed the username of the user being
removed as the first and only parameter. The return
code of the command is not taken into account.
Default: None, no command is run
EXAMPLE
The following example shows a typical SSSD config. It does
not describe configuration of the domains themselves - refer to
documentation on configuring domains for more details.
[sssd]
domains = LDAP
services = nss, pam
config_file_version = 2
[nss]
filter_groups = root
filter_users = root
[pam]
[domain/LDAP]
id_provider = ldap
ldap_uri = ldap://ldap.example.com
ldap_search_base = dc=example,dc=com
auth_provider = krb5
krb5_server = kerberos.example.com
krb5_realm = EXAMPLE.COM
cache_credentials = true
min_id = 10000
max_id = 20000
enumerate = False