sssd-sudo - Configuring sudo with the SSSD back end
This manual page describes how to configure sudo
(8) to work with
(8) and how SSSD caches sudo rules.
To enable SSSD as a source for sudo rules, add sss
to the sudoers
entry in nsswitch.conf
For example, to configure sudo to first lookup rules in the standard
(5) file (which should contain rules that apply to local users)
and then in SSSD, the nsswitch.conf file should contain the following line:
More information about configuring the sudoers search order from the
nsswitch.conf file as well as information about the LDAP schema that is used
to store sudo rules in the directory can be found in sudoers.ldap
: in order to use netgroups or IPA hostgroups in sudo rules, you also
need to correctly set nisdomainname
(1) to your NIS domain name (which
equals to IPA domain name when using hostgroups).
All configuration that is needed on SSSD side is to extend the list of
with "sudo" in [sssd] section of
(5). To speed up the LDAP lookups, you can also set search
base for sudo rules using ldap_sudo_search_base
The following example shows how to configure SSSD to download sudo rules from an
config_file_version = 2
services = nss, pam, sudo
domains = EXAMPLE
id_provider = ldap
sudo_provider = ldap
ldap_uri = ldap://example.com
ldap_sudo_search_base = ou=sudoers,dc=example,dc=com
It's important to note that on platforms where systemd is supported there's no
need to add the "sudo" provider to the list of services, as it
became optional. However, sssd-sudo.socket must be enabled instead.
When SSSD is configured to use IPA as the ID provider, the sudo provider is
automatically enabled. The sudo search base is configured to use the IPA
native LDAP tree (cn=sudo,$SUFFIX). If any other search base is defined in
sssd.conf, this value will be used instead. The compat tree
(ou=sudoers,$SUFFIX) is no longer required for IPA sudo functionality.
The biggest challenge, when developing sudo support in SSSD, was to ensure that
running sudo with SSSD as the data source provides the same user experience
and is as fast as sudo but keeps providing the most current set of rules as
possible. To satisfy these requirements, SSSD uses three kinds of updates.
They are referred to as full refresh, smart refresh and rules refresh.
The smart refresh
periodically downloads rules that are new or were
modified after the last update. Its primary goal is to keep the database
growing by fetching only small increments that do not generate large amounts
of network traffic.
The full refresh
simply deletes all sudo rules stored in the cache and
replaces them with all rules that are stored on the server. This is used to
keep the cache consistent by removing every rule which was deleted from the
server. However, full refresh may produce a lot of traffic and thus it should
be run only occasionally depending on the size and stability of the sudo
The rules refresh
ensures that we do not grant the user more permission
than defined. It is triggered each time the user runs sudo. Rules refresh will
find all rules that apply to this user, check their expiration time and
redownload them if expired. In the case that any of these rules are missing on
the server, the SSSD will do an out of band full refresh because more rules
(that apply to other users) may have been deleted.
If enabled, SSSD will store only rules that can be applied to this machine. This
means rules that contain one of the following values in sudoHost
•netgroup (in the form
•hostname or fully qualified domain
name of this machine
•one of the IP addresses of this
•one of the IP addresses of the network
(in the form "address/mask")
There are many configuration options that can be used to adjust the behavior.
Please refer to "ldap_sudo_*" in sssd-ldap
"sudo_*" in sssd.conf
The SSSD upstream - https://pagure.io/SSSD/sssd/