NAME
idmap_tdb - Samba's idmap_tdb Backend for Winbind
DESCRIPTION
The idmap_tdb plugin is the default backend used by winbindd for
storing SID/uid/gid mapping tables.
In contrast to read only backends like idmap_rid, it is an allocating
backend: This means that it needs to allocate new user and group IDs in
order to create new mappings. The allocator can be provided by the
idmap_tdb backend itself or by any other allocating backend like
idmap_ldap or idmap_tdb2. This is configured with the parameter idmap
alloc backend.
Note that in order for this (or any other allocating) backend to
function at all, the default backend needs to be writeable. The ranges
used for uid and gid allocation are the default ranges configured by
"idmap uid" and "idmap gid".
Furthermore, since there is only one global allocating backend
responsible for all domains using writeable idmap backends, any
explicitly configured domain with idmap backend tdb should have the
same range as the default range, since it needs to use the global uid /
gid allocator. See the example below.
IDMAP OPTIONS
range = low - high
Defines the available matching uid and gid range for which the
backend is authoritative. If the parameter is absent, Winbind fails
over to use the "idmap uid" and "idmap gid" options from smb.conf.
EXAMPLES
This example shows how tdb is used as a the default idmap backend. It
configures the idmap range through the global options for all domains
encountered. This same range is used for uid/gid allocation.
[global]
# "idmap backend = tdb" is redundant here since it is the default
idmap backend = tdb
idmap uid = 1000000-2000000
idmap gid = 1000000-2000000
This (rather theoretical) example shows how tdb can be used as the
allocating backend while ldap is the default backend used to store the
mappings. It adds an explicit configuration for some domain DOM1, that
uses the tdb idmap backend. Note that the same range as the default
uid/gid range is used, since the allocator has to serve both the
default backend and the explicitly configured domain DOM1.
[global]
idmap backend = ldap
idmap uid = 1000000-2000000
idmap gid = 1000000-2000000
# use a different uid/gid allocator:
idmap alloc backend = tdb
idmap config DOM1 : backend = tdb
idmap config DOM1 : range = 1000000-2000000
AUTHOR
The original Samba software and related utilities were created by
Andrew Tridgell. Samba is now developed by the Samba Team as an Open
Source project similar to the way the Linux kernel is developed.