path: root/docs/docbook/manpages/smbpasswd.8.sgml

Namesmbpasswd - change a users SMB password 
Synopsis
smbpasswd [-a] [-x] [-d]
[-e] [-D debug level] [-n] [-r remote_machine] [-R name resolve order] [-m] [-j
DOMAIN] [-U username] [-h] [-s] username 
Description
This program is part of
the Samba suite. 
The smbpasswd program has several different functions,
depending on whether it is run by the root user or not. When run as a normal
user it allows the user to change the password used for their SMB sessions
on any machines that store SMB passwords. 
By default (when run with no arguments)
it will attempt to change the current users SMB password on the local machine.
This is similar to the way the passwd (1) program works. smbpasswd differs
from how the passwd program works however in that it is not setuid root
but works in a client-server mode and communicates with a locally running
smbd. As a consequence in order for this to succeed the smbd daemon must
be running on the local machine. On a UNIX machine the encrypted SMB passwords
are usually stored in the smbpasswd (5) file. 
When run by an ordinary user
with no options. smbpasswd will prompt them for their old smb password and
then ask them for their new password twice, to ensure that the new password
was typed correctly. No passwords will be echoed on the screen whilst being
typed. If you have a blank smb password (specified by the string "NO PASSWORD"
in the smbpasswd file) then just press the <Enter> key when asked for your
old password. 
smbpasswd can also be used by a normal user to change their
SMB password on remote machines, such as Windows NT Primary Domain Controllers.
See the (-r) and -U options below. 
When run by root, smbpasswd allows new
users to be added and deleted in the smbpasswd file, as well as allows
changes to the attributes of the user in this file to be made. When run
by root, smbpasswd accesses the local smbpasswd file directly, thus enabling
changes to be made even if smbd is not running. 
Options
-aThis option specifies
that the username following should be added to the local smbpasswd file,
with the new password typed (type <Enter> for the old password). This option
is ignored if the username following already exists in the smbpasswd file
and it is treated like a regular change password command. Note that the
user to be added must already exist in the system password file (usually
/etc/passwd) else the request to add the user will fail. This option is
only available when running smbpasswd as root. -xThis option specifies that
the username following should be deleted from the local smbpasswd file.
This option is only available when running smbpasswd as root. -dThis option
specifies that the username following should be disabled in the local smbpasswd
file. This is done by writing a 'D' flag into the account control space in
the smbpasswd file. Once this is done all attempts to authenticate via SMB
using this username will fail. If the smbpasswd file is in the 'old' format
(pre-Samba 2.0 format) there is no space in the users password entry to write
this information and so the user is disabled by writing 'X' characters into
the password space in the smbpasswd file. See smbpasswd (5) for details
on the 'old' and new password file formats. This option is only available
when running smbpasswd as root. -eThis option specifies that the username
following should be enabled in the local smbpasswd file, if the account
was previously disabled. If the account was not disabled this option has
no effect. Once the account is enabled then the user will be able to authenticate
via SMB once again. If the smbpasswd file is in the 'old' format then smbpasswd
will prompt for a new password for this user, otherwise the account will
be enabled by removing the 'D' flag from account control space in the smbpasswd
file. See smbpasswd (5) for details on the 'old' and new password file formats.
This option is only available when running smbpasswd as root. -D debugleveldebuglevel
is an integer from 0 to 10.  The default value if this parameter is not
specified is zero. The higher this value, the more detail will be logged
to the log files about the activities of smbpasswd. At level 0, only critical
errors and serious warnings will be logged. Levels above 1 will generate
considerable amounts of log data, and should only be used when investigating
a problem. Levels above 3 are designed for use only by developers and generate
HUGE amounts of log data, most of which is extremely cryptic. -nThis option
specifies that the username following should have their password set to
null (i.e. a blank password) in the local smbpasswd file. This is done by
writing the string "NO PASSWORD" as the first part of the first password
stored in the smbpasswd file. Note that to allow users to logon to a Samba
server once the password has been set to "NO PASSWORD" in the smbpasswd
file the administrator must set the following parameter in the [global]
section of the smb.conf file : null passwords = true This option is only
available when running smbpasswd as root. -r remote machine nameThis option
allows a user to specify what machine they wish to change their password
on. Without this parameter smbpasswd defaults to the local host. The "remote
machine name" is the NetBIOS name of the SMB/CIFS server to contact to
attempt the password change. This name is resolved into an IP address using
the standard name resolution mechanism in all programs of the Samba suite.
See the -R name resolve order parameter for details on changing this resolving
mechanism. The username whose password is changed is that of the current
UNIX logged on user. See the -U username parameter for details on changing
the password for a different username. Note that if changing a Windows NT
Domain password the remote machine specified must be the Primary Domain
Controller for the domain (Backup Domain Controllers only have a read-only
copy of the user account database and will not allow the password change).
Note that Windows 95/98 do not have a real password database so it is not
possible to change passwords specifying a Win95/98  machine as remote machine
target. -R name resolve orderThis option allows the user of smbclient to
determine what name resolution services to use when looking up the NetBIOS
name of the host being connected to. The options are :"lmhosts", "host",
"wins" and "bcast". They cause names to be resolved as follows : olmhosts
: Lookup an IP address in the Samba lmhosts file. ohost : Do a standard
host name to IP address resolution, using the system /etc/hosts, NIS, or
DNS lookups. This method of name resolution is operating system dependent.
For instance on IRIX or Solaris, this may be controlled by the /etc/nsswitch.conf
file). owins : Query a name with the IP address listed in the  wins server
parameter in the  smb.conf file. If  no WINS server has been specified this
method will be ignored. obcast : Do a broadcast on each of the known local
interfaces listed in the interfaces parameter in the smb.conf file. This
is the least reliable of the name resolution methods as it depends on the
target host being on a locally connected subnet. If this parameter is not
set then the name resolve order defined in the smb.conf file parameter 
name resolve order will be used. The default order is lmhosts, host, wins,
bcast and without this parameter or any entry in the smb.conf  file the
name resolution methods will be attempted in this order. -mThis option tells
smbpasswd that the account being changed is a MACHINE account. Currently
this is used when Samba is being used as an NT Primary Domain Controller.
PDC support is not a supported feature in Samba2.0 but will become supported
in a later release. If you wish to know more about using Samba as an NT
PDC then please subscribe to the mailing list samba-ntdom@samba.org. This
option is only available when running smbpasswd as root. -j DOMAINThis option
is used to add a Samba server into a Windows NT Domain, as a Domain member
capable of authenticating user accounts to any Domain Controller in the
same way as a Windows NT Server. See the security=domain option in the smb.conf
(5) man page. In order to be used in this way, the Administrator for the
Windows NT Domain must have used the program "Server Manager for Domains"
to add the primary NetBIOS name of  the Samba server as a member of the
Domain. After this has been done, to join the Domain invoke smbpasswd with
this parameter. smbpasswd will then look up the Primary Domain Controller
for the Domain (found in the smb.conf file in the parameter password server
and change the machine account password used to create the secure Domain
communication.  This password is then stored by smbpasswd in a file, read
only by root, called CW<Domain>.<Machine>.mac where CW<Domain> is the name of the
Domain we are joining and CW<Machine> is the primary NetBIOS name of the
machine we are running on. Once this operation has been performed the smb.conf
file may be updated to set the security=domain option and all future logins
to the Samba server will be authenticated to the Windows NT PDC. Note that
even though the authentication is being done to the PDC all users accessing
the Samba server must still have a valid UNIX account on that machine. This
option is only available when running smbpasswd as root. -U usernameThis
option may only be used in conjunction with the -r option. When changing
a password on a remote machine it allows the user to specify the user name
on that machine whose password will be changed. It is present to allow users
who have different user names on different systems to change these passwords.
-hThis option prints the help string for smbpasswd,  selecting the correct
one for running as root or as an ordinary user. -sThis option causes smbpasswd
to be silent (i.e. not issue prompts) and to read it's old and new passwords
from standard  input, rather than from CW/dev/tty (like the passwd (1)
program does). This option is to aid people writing scripts to drive smbpasswd
usernameThis specifies the username for all of the root only options to
operate on. Only root can specify this parameter as only root has the permission
needed to modify attributes directly in the local smbpasswd file. NotesSince
smbpasswd works in client-server mode communicating with a local smbd for
a non-root user then the smbd daemon must be running for this to work. A
common problem is to add a restriction to the hosts that may access the
smbd running on the local machine by specifying a "allow hosts" or "deny
hosts" entry in the smb.conf file and neglecting to allow "localhost" access
to the smbd. In addition, the smbpasswd command is only useful if Samba
has been set up to use encrypted passwords. See the file ENCRYPTION.txt in
the docs directory for details on how to do this. VersionThis man page is
correct for version 2.0 of the Samba suite. AuthorThe original Samba software
and related utilities were created by Andrew Tridgell samba@samba.org. Samba
is now developed by the Samba Team as an Open Source project similar to
the way the Linux kernel is developed. The original Samba man pages were
written by Karl Auer. The man page sources were converted to YODL format
(another excellent piece of Open Source software, available at ftp://ftp.icce.rug.nl/pub/unix/)
and updated for the Samba2.0 release by Jeremy Allison. samba@samba.org. See
samba (7) to find out how to get a full list of contributors and details
on how to submit bug reports, comments etc.