idmap_rid
8
Samba
System Administration tools
3.6
idmap_rid
Samba's idmap_rid Backend for Winbind
DESCRIPTION
The idmap_rid backend provides a way to use an algorithmic
mapping scheme to map UIDs/GIDs and SIDs. No database is required
in this case as the mapping is deterministic.
IDMAP OPTIONS
range = low - high
Defines the available matching uid and gid range for which the
backend is authoritative. Note that the range acts as a filter.
If algorithmically determined UID or GID fall outside the
range, they are ignored and the corresponding map is discarded.
It is intended as a way to avoid accidental UID/GID overlaps
between local and remotely defined IDs.
base_rid = INTEGER
Defines the base integer used to build SIDs out of a UID or a GID,
and to rebase the UID or GID to be obtained from a SID.
This means SIDs with a RID less than the base rid are filtered.
The default is not to restrict the allowed rids at all,
i.e. a base_rid value of 0.
A good value for the base_rid can be 1000, since user
RIDs by default start at 1000 (512 hexadecimal).
Use of this parameter is deprecated.
THE MAPPING FORMULAS
The Unix ID for a RID is calculated this way:
ID = RID - BASE_RID + LOW_RANGE_ID.
Correspondingly, the formula for calculating the RID for a
given Unix ID is this:
RID = ID + BASE_RID - LOW_RANGE_ID.
EXAMPLES
This example shows how to configure two domains with idmap_rid,
the principal domain and a trusted domain, leaving the default
id mapping scheme at tdb. The example also demonstrates the use
of the base_rid parameter for the trusted domain.
[global]
security = domain
workgroup = MAIN
idmap backend = tdb
idmap uid = 1000000-1999999
idmap gid = 1000000-1999999
idmap config MAIN : backend = rid
idmap config MAIN : range = 10000 - 49999
idmap config TRUSTED : backend = rid
idmap config TRUSTED : range = 50000 - 99999
idmap config TRUSTED : base_rid = 1000
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.