winbindd [-d debuglevel] [-i]
This program is part of the Samba suite version 3.0 and describes functionality not yet implemented in the main version of Samba.
winbindd is a daemon that provides a service for the Name Service
Switch capability that is present in most modern C libraries. The Name
Service Switch allows user and system information to be obtained from
different databases services such as NIS or DNS. The exact behaviour can
be configured throught the /etc/nsswitch.conf file. Users and groups
are allocated as they are resolved to a range of user and group ids
specified by the administrator of the Samba system.
The service provided by winbindd is called `winbind' and can be used to resolve user and group information from a Windows NT server.
The following nsswitch databases are implemented by the winbindd service:
User information traditionally stored in the passwd(5) file and used by getpwent(3) functions.
Group information traditionally stored in the group(5) file and used by getgrent(3) functions.
For example, the following simple configuration in the
/etc/nsswitch.conf file can be used to initially resolve user and group
information from /etc/passwd and /etc/group and then from the
Windows NT server.
passwd: files winbind
group: files winbind
The following options are available to the winbindd daemon:
Users and groups on a Windows NT server are assigned a relative id (rid) which is unique for the domain when the user or group is created. To convert the Windows NT user or group into a unix user or group, a mapping between rids and unix user and group ids is required. This is one of the jobs that winbindd performs.
As winbindd users and groups are resolved from a server, user and group ids are allocated from a specified range. This is done on a first come, first served basis, although all existing users and groups will be mapped as soon as a client performs a user or group enumeration command. The allocated unix ids are stored in a database file under the Samba lock directory and will be remembered.
WARNING: The rid to unix id database is the only location where the user and group mappings are stored by winbindd. If this file is deleted or corrupted, there is no way for winbindd to determine which user and group ids correspond to Windows NT user and group rids.
Configuration of the winbindd daemon is done through configuration parameters in the smb.conf file. All parameters should be specified in the [global] section of smb.conf.
The winbind uid parameter specifies the range of user ids that are allocated by the winbindd daemon. This range of ids should have no existing local or nis users within it as strange conflicts can occur otherwise.
Default:
winbind uid = <empty string>
Example:
winbind uid = 10000-20000
The winbind gid parameter specifies the range of group ids that are allocated by the winbindd daemon. This range of group ids should have no existing local or nis groups within it as strange conflicts can occur otherwise.
Default:
winbind gid = <empty string>
Example:
winbind gid = 10000-20000
This parameter specifies the number of seconds the winbindd daemon will cache user and group information before querying a Windows NT server again.
Default:
winbind cache type = 15
When filling out the user information for a Windows NT user, the
winbindd daemon uses this parameter to fill in
the home directory for that user. If the string %D is present it is
substituted with the user's Windows NT domain name. If the string %U
is present it is substituted with the user's Windows NT user name.
Default:
template homedir = /home/%D/%U
When filling out the user information for a Windows NT user, the
winbindd daemon uses this parameter to fill in
the home directory for that user. If the string %D is present it is
substituted with the user's Windows NT domain name. If the string %U
is present it is substituted with the user's Windows NT user name.
Default:
template homedir = /home/%D/%U
The following files are relevant to the operation of the winbindd daemon.
Name service switch configuration file.
The UNIX pipe over which clients communicate with the winbindd program.
For security reasons, the winbind client will only attempt to connect to the
winbindd daemon if both the /tmp/.winbindd directory and
/tmp/.winbindd/pipe file are owned by root.
Implementation of name service switch library.
Storage for the Windows NT rid to UNIX user/group id mapping. If this file is damaged or destroyed then the mappings will be lost.
The lock directory is specified when Samba is initially compiled using the
--with-lockdir option. This directory is by default
/usr/local/samba/var/locks.
Storage for cached user and group information.
samba(7), smb.conf(5), nsswitch.conf(5)
The original Samba software and related utilities were created by Andrew Tridgell samba-bugs@samba.org. Samba is now developed by the Samba Team as an Open Source project similar to the way the Linux kernel is developed.
Winbindd was written by Tim Potter.