SMBPASSWD
Section: Maintenance Commands (8)
Updated: 26 Apr 2000
Index
Return to Main Contents
NAME
smbpasswd - 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
-
- -a
-
This 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.
-
- -x
-
This option specifies that the username following should
be deleted from the local smbpasswd file.
-
This option is only available when running smbpasswd as
root.
-
- -d
-
This 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.
-
- -e
-
This 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 debuglevel
-
debuglevel 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.
-
- -n
-
This 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 name
-
This 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 order
-
This 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 :
-
-
- o
-
lmhosts : Lookup an IP address in the Samba lmhosts file.
-
- o
-
host : 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).
-
- o
-
wins : 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.
-
- o
-
bcast : 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.
-
- -m
-
This 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 DOMAIN
-
This 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 <Domain>.<Machine>.mac where
<Domain> is the name of the Domain we are joining and <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 username
-
This 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.
-
- -h
-
This option prints the help string for smbpasswd,
selecting the correct one for running as root or as an ordinary user.
-
- -s
-
This 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 /dev/tty (like the passwd (1) program
does). This option is to aid people writing scripts to drive smbpasswd
-
- username
-
This 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.
-
NOTES
-
Since 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.
-
VERSION
-
This man page is correct for version 2.0 of the Samba suite.
-
AUTHOR
-
The 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.
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- OPTIONS
-
- NOTES
-
- VERSION
-
- AUTHOR
-
This document was created by
man2html,
using the manual pages.
Time: 01:51:16 GMT, July 11, 2022