GNU/Linux |
Debian 6.0.2(Squeeze) |
|
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idmap_tdb2(8) |
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NAME
idmap_tdb2 − Samba´s idmap_tdb2 Backend for
Winbind
DESCRIPTION
The idmap_tdb2 plugin is a substitute for the default
idmap_tdb backend used by winbindd for storing SID/uid/gid
mapping tables in clustered environments with Samba and
CTDB.
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_tdb2 backend itself or by any other allocating backend like idmap_tdb or idmap_ldap. 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 tdb2 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.
IDMAP
SCRIPT
The tdb2 idmap backend supports a script for performing id
mappings through the smb.conf option idmap : script.
The script should accept the following command line
options.
SIDTOID S−1−xxxx |
||
IDTOSID UID xxxx |
||
IDTOSID GID xxxx |
And it should return one of the following responses as a single line of text.
UID:yyyy
GID:yyyy | |
SID:yyyy | |
ERR:yyyy |
Note that the script should cover the complete range of SIDs that can be passed in for SID to Unix ID mapping, since otherwise SIDs unmapped by the script might get mapped to IDs that had previously been mapped by the script.
EXAMPLES
This example shows how tdb2 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 = tdb2 | |
idmap uid = 1000000−2000000 | |
idmap gid = 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.
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idmap_tdb2(8) | ![]() |