idmap_tdb2
8
Samba
System Administration tools
4.0
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.
IDMAP OPTIONS
range = low - high
Defines the available matching uid and gid range for which the
backend is authoritative.
script
This option can be used to configure an external program
for performing id mappings instead of using the tdb
counter. The mappings are then stored int tdb2 idmap
database. For details see the section on IDMAP SCRIPT below.
IDMAP SCRIPT
The tdb2 idmap backend supports an external program for performing id mappings
through the smb.conf option idmap config * : script or
its deprecated legacy form idmap : script.
The mappings obtained by the script are then stored in the idmap tdb2
database instead of mappings created by the incrementing id counters.
It is therefore important that the script covers 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.
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
EXAMPLES
This example shows how tdb2 is used as a the default idmap backend.
[global]
idmap config * : backend = tdb2
idmap config * : range = 1000000-2000000
This example shows how tdb2 is used as a the default idmap backend
using an external program via the script parameter:
[global]
idmap config * : backend = tdb2
idmap config * : range = 1000000-2000000
idmap config * : script = /usr/local/samba/bin/idmap_script.sh
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.