The idmap_ad plugin provides a way for Winbind to read id mappings from an AD server that uses RFC2307/SFU schema extensions. This module implements only the "idmap" API, and is READONLY. Mappings must be provided in advance by the administrator by adding the uidNumber attributes for users and gidNumber attributes for groups in the AD. Winbind will only map users that have a uidNumber and whose primary group have a gidNumber attribute set. It is however recommended that all groups in use have gidNumber attributes assigned, otherwise they are not working.
backend does not work as the default idmap backend, but one has to configure it separately for each domain for which one wants to use it, using disjoint ranges. One usually needs to configure a writeable default idmap range, using for example the
backend, in order to be able to map the BUILTIN sids and possibly other trusted domains. The writeable default config is also needed in order to be able to create group mappings. This catch-all default idmap configuration should have a range that is disjoint from any explicitly configured domain with idmap backend
ad. See the example below.
The following example shows how to retrieve idmappings from our principal and trusted AD domains. If trusted domains are present id conflicts must be resolved beforehand, there is no guarantee on the order conflicting mappings would be resolved at this point. This example also shows how to leave a small non conflicting range for local id allocation that may be used in internal backends like BUILTIN.
workgroup = CORP
idmap config * : backend = tdb
idmap config * : range = 1000000-1999999
idmap config CORP : backend = ad
idmap config CORP : range = 1000-999999