path: root/docs/Samba3-HOWTO/TOSHARG-TheNetCommand.xml

<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE chapter PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">

<chapter id="NetCommand">
<chapterinfo>
	&author.jht;
	&author.vl;
	&author.gd;
	<pubdate>May 9, 2005</pubdate>
</chapterinfo>

<title>Remote and Local Management: The Net Command</title>

<para>
<indexterm><primary>net</primary></indexterm>
<indexterm><primary>remote management</primary></indexterm>
<indexterm><primary>command-line</primary></indexterm>
<indexterm><primary>scripted control</primary></indexterm>
The <command>net</command> command is one of the new features of Samba-3 and is an attempt to provide a useful
tool for the majority of remote management operations necessary for common tasks. The <command>net</command>
tool is flexible by design and is intended for command-line use as well as for scripted control application.
</para>

<para>
<indexterm><primary>net</primary></indexterm>
<indexterm><primary>network administrator's toolbox</primary></indexterm>
<indexterm><primary>smbgroupedit</primary></indexterm>
<indexterm><primary>rpcclient</primary></indexterm>
Originally introduced with the intent to mimic the Microsoft Windows command that has the same name, the
<command>net</command> command has morphed into a very powerful instrument that has become an essential part
of the Samba network administrator's toolbox. The Samba Team has introduced tools, such as
<command>smbgroupedit</command> and <command>rpcclient</command>, from which really useful capabilities have
been integrated into the <command>net</command>. The <command>smbgroupedit</command> command was absorbed
entirely into the <command>net</command>, while only some features of the <command>rpcclient</command> command
have been ported to it. Anyone who finds older references to these utilities and to the functionality they
provided should look at the <command>net</command> command before searching elsewhere.
</para>

<para>
A Samba-3 administrator cannot afford to gloss over this chapter because to do so will almost certainly cause
the infliction of self-induced pain, agony, and desperation. Be warned: this is an important chapter.
</para>

	<sect1>
	<title>Overview</title>

	<para>
<indexterm><primary>standalone</primary></indexterm>
<indexterm><primary>domain member</primary></indexterm>
<indexterm><primary>PDC</primary></indexterm>
<indexterm><primary>BDC</primary></indexterm>
<indexterm><primary>DMS</primary></indexterm>
<indexterm><primary>authentication</primary></indexterm>
	The tasks that follow the installation of a Samba-3 server, whether standalone or domain member, of a
	domain controller (PDC or BDC) begins with the need to create administrative rights. Of course, the
	creation of user and group accounts is essential for both a standalone server and a PDC.
	In the case of a BDC or a Domain Member server (DMS), domain user and group accounts are obtained from
	the central domain authentication backend.
	</para>

	<para>
<indexterm><primary>server type</primary></indexterm>
<indexterm><primary>local UNIX groups</primary></indexterm>
<indexterm><primary>mapped</primary></indexterm>
<indexterm><primary>domain global group</primary></indexterm>
<indexterm><primary>UID</primary></indexterm>
<indexterm><primary>GID</primary></indexterm>
<indexterm><primary>access rights</primary></indexterm>
<indexterm><primary>net</primary></indexterm>
	Regardless of the type of server being installed, local UNIX groups must be mapped to the Windows
	networking domain global group accounts. Do you ask why? Because Samba always limits its access to
	the resources of the host server by way of traditional UNIX UID and GID controls. This means that local
	groups must be mapped to domain global groups so that domain users who are members of the domain
	global groups can be given access rights based on UIDs and GIDs local to the server that is hosting
	Samba. Such mappings are implemented using the <command>net</command> command.
	</para>

	<para>
<indexterm><primary>PDC</primary></indexterm>
<indexterm><primary>BDC</primary></indexterm>
<indexterm><primary>DMS</primary></indexterm>
<indexterm><primary>security account</primary></indexterm>
<indexterm><primary>domain authentication</primary></indexterm>
<indexterm><primary>trust accounts</primary></indexterm>
<indexterm><primary>net</primary></indexterm>
	UNIX systems that are hosting a Samba-3 server that is running as a member (PDC, BDC, or DMS) must have
	a machine security account in the domain authentication database (or directory). The creation of such
	security (or trust) accounts is also handled using the <command>net</command> command.
	</para>

	<para>
<indexterm><primary>interdomain trusts</primary></indexterm>
<indexterm><primary>net</primary></indexterm>
<indexterm><primary>administrative duties</primary></indexterm>
<indexterm><primary>user management</primary></indexterm>
<indexterm><primary>group management</primary></indexterm>
<indexterm><primary>share management</primary></indexterm>
<indexterm><primary>printer management</primary></indexterm>
<indexterm><primary>printer migration</primary></indexterm>
<indexterm><primary>SID management</primary></indexterm>
	The establishment of interdomain trusts is achieved using the <command>net</command> command also, as
	may a plethora of typical administrative duties such as user management, group management, share and
	printer management, file and printer migration, security identifier management, and so on.
	</para>

	<para>
<indexterm><primary>net</primary></indexterm>
<indexterm><primary>man pages</primary></indexterm>
	The overall picture should be clear now: the <command>net</command> command plays a central role
	on the Samba-3 stage. This role will continue to be developed. The inclusion of this chapter is
	evidence of its importance, one that has grown in complexity to the point that it is no longer considered
	prudent to cover its use fully in the online UNIX man pages.
	</para>

	</sect1>
	
	<sect1>
	<title>Administrative Tasks and Methods</title>

	<para>
<indexterm><primary>net</primary></indexterm>
<indexterm><primary>ADS</primary></indexterm>
<indexterm><primary>Distributed Computing Environment</primary><see>DCE</see></indexterm>
<indexterm><primary>Remote Procedure Call</primary><see>RPC</see></indexterm>
	The basic operations of the <command>net</command> command are documented here. This documentation is not
	exhaustive, and thus it is incomplete. Since the primary focus is on migration from Windows servers to a Samba
	server, the emphasis is on the use of the Distributed Computing Environment Remote Procedure Call (DCE RPC)
	mode of operation. When used against a server that is a member of an Active Directory domain, it is preferable
	(and often necessary) to use ADS mode operations. The <command>net</command> command supports both, but not
	for every operation. For most operations, if the mode is not specified, <command>net</command> will
	automatically fall back via the <constant>ads</constant>, <constant>rpc</constant>, and
	<constant>rap</constant> modes.  Please refer to the man page for a more comprehensive overview of the
	capabilities of this utility.
	</para>

	</sect1>

	<sect1>
	<title>UNIX and Windows Group Management</title>

	<para>
<indexterm><primary>Active Directory</primary></indexterm>
<indexterm><primary>net</primary><secondary>rpc</secondary></indexterm>
<indexterm><primary>net</primary><secondary>ads</secondary></indexterm>
<indexterm><primary>net</primary><secondary>rap</secondary></indexterm>
<indexterm><primary>RAP</primary></indexterm>
	As stated, the focus in most of this chapter is on use of the <command>net rpc</command> family of
	operations that are supported by Samba. Most of them are supported by the <command>net ads</command>
	mode when used in connection with Active Directory. The <command>net rap</command> operating mode is
	also supported for some of these operations. RAP protocols are used by IBM OS/2 and by several
	earlier SMB servers.
	</para>

	<para>
<indexterm><primary>net</primary></indexterm>
<indexterm><primary>user management</primary></indexterm>
<indexterm><primary>group management</primary></indexterm>
	Samba's <command>net</command> tool implements sufficient capability to permit all common administrative
	tasks to be completed from the command line. In this section each of the essential user and group management
	facilities are explored.
	</para>

	<para>
<indexterm><primary>groups</primary></indexterm>
<indexterm><primary>domain</primary><secondary>groups</secondary></indexterm>
<indexterm><primary>local</primary><secondary>groups</secondary></indexterm>
<indexterm><primary>domain user accounts</primary></indexterm>
	Samba-3 recognizes two types of groups: <emphasis>domain groups</emphasis> and <emphasis>local
	groups</emphasis>. Domain groups can contain (have as members) only domain user accounts. Local groups
	can contain local users, domain users, and domain groups as members.
	</para>

	<para>
	The purpose of a local group is to permit file permission to be set for a group account that, like the
	usual UNIX/Linux group, is persistent across redeployment of a Windows file server.
	</para>

	<sect2>
	<title>Adding, Renaming, or Deletion of Group Accounts</title>

	<para>
	Samba provides file and print services to Windows clients. The file system resources it makes available
	to the Windows environment must, of necessity, be provided in a manner that is compatible with the
	Windows networking environment. UNIX groups are created and deleted as required to serve operational
	needs in the UNIX operating system and its file systems.
	</para>

	<para>
	In order to make available to the Windows environment Samba has a facility by which UNIX groups can
	be mapped to a logical entity, called a Windows (or domain) group. Samba supports two types of Windows
	groups, local and global. Global groups can contain as members, global users. This membership is
	affected in the normal UNIX manner, but adding UNIX users to UNIX groups. Windows user accounts consist
	of a mapping between a user SambaSAMAccount (logical entity) and a UNIX user account. Therefore, 
	a UNIX user is mapped to a Windows user (i.e., is given a Windows user account and password) and the
	UNIX groups to which that user belongs, is mapped to a Windows group account. The result is that in
	the Windows account environment that user is also a member of the Windows group account by virtue
	of UNIX group memberships.
	</para>

	<para>
	The following sub-sections that deal with management of Windows groups demonstrates the relationship
	between the UNIX group account and its members to the respective Windows group accounts. It goes on to
	show how UNIX group members automatically pass-through to Windows group membership as soon as a logical
	mapping has been created.
	</para>

	<sect3>
	<title>Adding or Creating a New Group</title>

	<para>
	Before attempting to add a Windows group account, the currently available groups can be listed as shown
	here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group</tertiary></indexterm>
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group list</tertiary></indexterm>
<screen>
&rootprompt; net rpc group list -Uroot%not24get
Password:
Domain Admins
Domain Users
Domain Guests
Print Operators
Backup Operators
Replicator
Domain Computers
Engineers
</screen>
	A Windows group account called <quote>SupportEngrs</quote> can be added by executing the following
command:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group add</tertiary></indexterm>
<screen>
&rootprompt; net rpc group add "SupportEngrs" -Uroot%not24get
</screen>
	The addition will result in immediate availability of the new group account as validated by executing
this command:
<screen>
&rootprompt; net rpc group list -Uroot%not24get
Password:
Domain Admins
Domain Users
Domain Guests
Print Operators
Backup Operators
Replicator
Domain Computers
Engineers
SupportEngrs
</screen>
	</para>

	<para>
<indexterm><primary>POSIX</primary></indexterm>
<indexterm><primary>smbldap-groupadd</primary></indexterm>
<indexterm><primary>getent</primary></indexterm>
	The following demonstrates that the POSIX (UNIX/Linux system account) group has been created by calling
	the <smbconfoption name="add group script">/opt/IDEALX/sbin/smbldap-groupadd -p "%g"</smbconfoption> interface
	script:
<screen>
&rootprompt; getent group
...
Domain Admins:x:512:root
Domain Users:x:513:jht,lct,ajt,met
Domain Guests:x:514:
Print Operators:x:550:
Backup Operators:x:551:
Replicator:x:552:
Domain Computers:x:553:
Engineers:x:1002:jht
SupportEngrs:x:1003:
</screen>
	The following demonstrates that the use of the <command>net</command> command to add a group account
results in immediate mapping of the POSIX group that has been created to the Windows group account as shown
here:
<indexterm><primary>net</primary><secondary>groupmap</secondary><tertiary>list</tertiary></indexterm>
<screen>
&rootprompt; net groupmap list
Domain Admins (S-1-5-21-72630-4128915-11681869-512) -> Domain Admins
Domain Users (S-1-5-21-72630-4128915-11681869-513) -> Domain Users
Domain Guests (S-1-5-21-72630-4128915-11681869-514) -> Domain Guests
Print Operators (S-1-5-21-72630-4128915-11681869-550) -> Print Operators
Backup Operators (S-1-5-21-72630-4128915-11681869-551) -> Backup Operators
Replicator (S-1-5-21-72630-4128915-11681869-552) -> Replicator
Domain Computers (S-1-5-21-72630-4128915-11681869-553) -> Domain Computers
Engineers (S-1-5-21-72630-4128915-11681869-3005) -> Engineers
SupportEngrs (S-1-5-21-72630-4128915-11681869-3007) -> SupportEngrs
</screen>
	</para>

	</sect3>

	<sect3>
	<title>Mapping Windows Groups to UNIX Groups</title>

	<para>
<indexterm><primary>mapped</primary></indexterm>
<indexterm><primary>Windows groups</primary></indexterm>
<indexterm><primary>system groups</primary></indexterm>
<indexterm><primary>access controls</primary></indexterm>
	Windows groups must be mapped to UNIX system (POSIX) groups so that file system access controls
	can be asserted in a manner that is consistent with the methods appropriate to the operating
	system that is hosting the Samba server.
	</para>

	<para>
<indexterm><primary>access controls</primary></indexterm>
<indexterm><primary>UID</primary></indexterm>
<indexterm><primary>GID</primary></indexterm>
<indexterm><primary>locally known UID</primary></indexterm>
	All file system (file and directory) access controls, within the file system of a UNIX/Linux server that is
	hosting a Samba server, are implemented using a UID/GID identity tuple. Samba does not in any way override
	or replace UNIX file system semantics. Thus it is necessary that all Windows networking operations that
	access the file system provide a mechanism that maps a Windows user to a particular UNIX/Linux group
	account. The user account must also map to a locally known UID.
	</para>

	<para>
<indexterm><primary>default mappings</primary></indexterm>
<indexterm><primary>Domain Admins</primary></indexterm>
<indexterm><primary>Domain Users</primary></indexterm>
<indexterm><primary>Domain Guests</primary></indexterm>
<indexterm><primary>Windows group</primary></indexterm>
<indexterm><primary>UNIX group</primary></indexterm>
<indexterm><primary>mapping</primary></indexterm>
	Samba depends on default mappings for the <constant>Domain Admins, Domain Users</constant>, and
	<constant>Domain Guests</constant> global groups. Additional groups may be added as shown in the
	examples just given. There are times when it is necessary to map an existing UNIX group account
	to a Windows group. This operation, in effect, creates a Windows group account as a consequence
	of creation of the mapping.
	</para>

	<para>
<indexterm><primary>net</primary><secondary>groupmap</secondary><tertiary>modify</tertiary></indexterm>
<indexterm><primary>net</primary><secondary>groupmap</secondary><tertiary>add</tertiary></indexterm>
<indexterm><primary>net</primary><secondary>groupmap</secondary><tertiary>delete</tertiary></indexterm>
	The operations that are permitted include: <constant>add</constant>, <constant>modify</constant>,
	and <constant>delete</constant>. An example of each operation is shown here.
	</para>

	<para>
	An existing UNIX group may be mapped to an existing Windows group by this example:
<screen>
&rootprompt; net groupmap modify ntgroup="Domain Users" unixgroup=users
</screen>
	An existing UNIX group may be mapped to a new Windows group as shown here:
<screen>
&rootprompt; net groupmap add ntgroup="EliteEngrs" unixgroup=Engineers type=d
</screen>
	Supported mapping types are 'd' (domain global) and 'l' (domain local).
	A Windows group may be deleted, and then a new Windows group can be mapped to the UNIX group by
	executing these commands:
<screen>
&rootprompt; net groupmap delete ntgroup=Engineers
&rootprompt; net groupmap add ntgroup=EngineDrivers unixgroup=Engineers type=d
</screen>
	The deletion and addition operations affected only the logical entities known as Windows groups, or domain
	groups. These operations are inert to UNIX system groups, meaning that they neither delete nor create UNIX
	system groups. The mapping of a UNIX group to a Windows group makes the UNIX group available as Windows
	groups so that files and folders on domain member clients (workstations and servers) can be given
	domain-wide access controls for domain users and groups.
	</para>

	<para>
	Two types of Windows groups can be created: <constant>domain (global)</constant> and <constant>local</constant>.
	In the previous examples the Windows groups created were of type <constant>domain</constant> or global. The
	following command will create a Windows group of type <constant>local</constant>.
<screen>
&rootprompt; net groupmap add ntgroup=Pixies unixgroup=pixies type=l
</screen>
	Supported mapping types are 'd' (domain global) and 'l' (domain local), a domain local group is Samba is
	treated as local to the individual Samba serverr. Local groups can be used with Samba to enable multiple
	nested group support.
	</para>

	</sect3>

	<sect3>
	<title>Deleting a Group Account</title>

	<para>
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group delete</tertiary></indexterm>
	A group account may be deleted by executing the following command:
<screen>
&rootprompt; net rpc group delete SupportEngineers -Uroot%not24get
</screen>
	</para>

	<para>
	Validation of the deletion is advisable. The same commands may be executed as shown above.
	</para>

	</sect3>

	<sect3>
	<title>Rename Group Accounts</title>

	<note><para>
	This command is not documented in the man pages; it is implemented in the source code, but it does not
	work. The example given documents (from the source code) how it should work. Watch the release notes
	of a future release to see when this may have been fixed.
	</para></note>

	<para>
	Sometimes it is necessary to rename a group account. Good administrators know how painful some managers'
	demands can be if this simple request is ignored. The following command demonstrates how the Windows group
	<quote>SupportEngrs</quote> can be renamed to <quote>CustomerSupport</quote>:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group rename</tertiary></indexterm>
<screen>
&rootprompt; net rpc group rename SupportEngrs \
    CustomerSupport -Uroot%not24get
</screen>
	</para>

	</sect3>

	</sect2>

	<sect2 id="grpmemshipchg">
	<title>Manipulating Group Memberships</title>

	<para>
	Three operations can be performed regarding group membership. It is possible to (1) add Windows users
	to a Windows group, to (2) delete Windows users from Windows groups, and to (3) list the Windows users that are
	members of a Windows group.
	</para>

	<para>
	To avoid confusion, it makes sense to check group membership before attempting to make any changes.
	The <command>getent group</command> will list UNIX/Linux group membership. UNIX/Linux group members are
	seen also as members of a Windows group that has been mapped using the <command>net groupmap</command>
	command (see <link linkend="groupmapping"/>). The following list of UNIX/Linux group membership shows
	that the user <constant>ajt</constant> is a member of the UNIX/Linux group <constant>Engineers</constant>.
<screen>
&rootprompt; getent group
...
Domain Admins:x:512:root
Domain Users:x:513:jht,lct,ajt,met,vlendecke
Domain Guests:x:514:
Print Operators:x:550:
Backup Operators:x:551:
Replicator:x:552:
Domain Computers:x:553:
Engineers:x:1000:jht,ajt
</screen>
	The UNIX/Linux groups have been mapped to Windows groups, as is shown here:
<screen>
&rootprompt; net groupmap list
Domain Admins (S-1-5-21-72630-412605-116429-512) -> Domain Admins
Domain Users (S-1-5-21-72630-412605-116429-513) -> Domain Users
Domain Guests (S-1-5-21-72630-412605-116429-514) -> Domain Guests
Print Operators (S-1-5-21-72630-412605-116429-550) -> Print Operators
Backup Operators (S-1-5-21-72630-412605-116429-551) -> Backup Operators
Replicator (S-1-5-21-72630-412605-116429-552) -> Replicator
Domain Computers (S-1-5-21-72630-412605-116429-553) -> Domain Computers
Engineers (S-1-5-21-72630-412605-116429-3001) -> Engineers
</screen>
	</para>

	<para>
	Given that the user <constant>ajt</constant> is already a member of the UNIX/Linux group and, via the
	group mapping, a member of the Windows group, an attempt to add this account again should fail. This is
	demonstrated here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group addmem</tertiary></indexterm>
<screen>
&rootprompt; net rpc group addmem "MIDEARTH\Engineers" ajt -Uroot%not24get
Could not add ajt to MIDEARTH\Engineers: NT_STATUS_MEMBER_IN_GROUP
</screen>
	This shows that the group mapping between UNIX/Linux groups and Windows groups is effective and
	transparent.
	</para>

	<para>
	To permit the user <constant>ajt</constant> to be added using the <command>net rpc group</command> utility,
	this account must first be removed. The removal and confirmation of its effect is shown here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group delmem</tertiary></indexterm>
<screen>
&rootprompt; net rpc group delmem "MIDEARTH\Engineers" ajt -Uroot%not24get
&rootprompt; getent group Engineers
Engineers:x:1000:jht
&rootprompt; net rpc group members Engineers -Uroot%not24get
MIDEARTH\jht
</screen>
	In this example both at the UNIX/Linux system level, the group no longer has the <constant>ajt</constant>
	as a member. The above also shows this to be the case for Windows group membership.
	</para>

	<para>
	The account is now added again, using the <command>net rpc group</command> utility:
<screen>
&rootprompt; net rpc group addmem "MIDEARTH\Engineers" ajt -Uroot%not24get
&rootprompt; getent group Engineers
Engineers:x:1000:jht,ajt
&rootprompt; net rpc group members Engineers -Uroot%not24get
MIDEARTH\jht
MIDEARTH\ajt
</screen>
	</para>

	<para>
	In this example the members of the Windows <constant>Domain Users</constant> account are validated using
	the <command>net rpc group</command> utility. Note the this contents of the UNIX/Linux group was shown
	four paragraphs earlier. The Windows (domain) group membership is shown here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group members</tertiary></indexterm>
<screen>
&rootprompt; net rpc group members "Domain Users" -Uroot%not24get
MIDEARTH\jht
MIDEARTH\lct
MIDEARTH\ajt
MIDEARTH\met
MIDEARTH\vlendecke
</screen>
	This express example shows that Windows group names are treated by Samba (as with
	MS Windows) in a case-insensitive manner:
<screen>
&rootprompt; net rpc group members "DomAiN USerS" -Uroot%not24get
MIDEARTH\jht
MIDEARTH\lct
MIDEARTH\ajt
MIDEARTH\met
MIDEARTH\vlendecke
</screen>
	</para>

	<note><para>
	An attempt to specify the group name as <constant>MIDEARTH\Domain Users</constant> in place of
	just simply <constant>Domain Users</constant> will fail. The default behavior of the net rpc group
	is to direct the command at the local machine. The Windows group is treated as being local to the machine.
	If it is necessary to query another machine, its name can be specified using the <constant>-S
	servername</constant> parameter to the <command>net</command> command.
	</para></note>

	</sect2>

	<sect2 id="nestedgrpmgmgt">
	<title>Nested Group Support</title>

	<para>
	It is possible in Windows (and now in Samba also) to create a local group that has members (contains),
	domain users, and domain global groups.  Creation of the local group <constant>demo</constant> is
	achieved by executing:
<screen>
&rootprompt; net rpc group add demo -L -S MORDON -Uroot%not24get
</screen>
	The -L switch means create a local group. Use the -S argument to direct the operation to a particular
	server. The parameters to the -U argument should be for a user who has appropriate administrative right
	and privileges on the machine.
	</para>

	<para>
	Addition and removal of group members can be achieved using the <constant>addmem</constant> and
	<constant>delmem</constant> subcommands of <command>net rpc group</command> command. For example,
	addition of <quote>DOM\Domain Users</quote> to the local group <constant>demo</constant> would be
	done by executing:
<screen>
&rootprompt; net rpc group addmem demo "DOM\Domain Users" -Uroot%not24get
</screen>
	</para>

	<para>
	The members of a nested group can be listed by executing the following:
<screen>
&rootprompt; net rpc group members demo -Uroot%not24get
DOM\Domain Users
DOM\Engineers
DOM\jamesf
DOM\jht
</screen>
	</para>

	<para>
	Nested group members can be removed (deleted) as shown here:
<screen>
&rootprompt; net rpc group delmem demo "DOM\jht" -Uroot%not24get
</screen>
	</para>

	<sect3>
	<title>Managing Nest Groups on Workstations from the Samba Server</title>

	<para>
	Windows network administrators often ask on the Samba mailing list how it is possible to grant everyone
	administrative rights on their own workstation. This is of course a very bad practice, but commonly done
	to avoid user complaints. Here is how it can be done remotely from a Samba PDC or BDC:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group addmem</tertiary></indexterm>
<screen>
&rootprompt; net rpc group addmem "Administrators" "Domain Users" \
    -S WINPC032 -Uadministrator%secret
</screen>
	</para>

	<para>
	This can be scripted, and can therefore be performed as a user logs onto the domain from a Windows
	workstation. Here is a simple example that shows how this can be done.
	</para>

	<procedure>
	<title>Automating User Addition to the Workstation Power Users Group</title>

		<step><para>
		Create the script shown in <link linkend="autopoweruserscript"></link> and locate it in
		the directory <filename>/etc/samba/scripts</filename>, named as <filename>autopoweruser.sh</filename>.
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>group addmem</tertiary></indexterm>
<indexterm><primary>autopoweruser.sh</primary></indexterm>
<indexterm><primary>/etc/samba/scripts</primary></indexterm>
		</para></step>

<example id="autopoweruserscript">
<title>Script to Auto-add Domain Users to Workstation Power Users Group</title>
<procedure>
#!/bin/bash

/usr/bin/net rpc group addmem "Power Users"  "DOMAIN_NAME\$1" -UAdministrator%secret -S $2

exit 0
</procedure>
</example>

		<step><para>
		Set the permissions on this script to permit it to be executed as part of the logon process:
<screen>
&rootprompt; chown root:root /etc/samba/autopoweruser.sh
&rootprompt; chmod 755 /etc/samba/autopoweruser.sh
</screen>
		</para></step>

		<step><para>
		Modify the &smb.conf; file so the <literal>NETLOGON</literal> stanza contains the parameters
		shown in <link linkend="magicnetlogon">the Netlogon Example smb.conf file</link>.
		</para></step>

<example id="magicnetlogon">
<title>A Magic Netlogon Share</title>
<smbconfblock>
<smbconfsection name="[netlogon]"/>
<smbconfoption name="comment">Netlogon Share</smbconfoption>
<smbconfoption name="path">/var/lib/samba/netlogon</smbconfoption>
<smbconfoption name="root preexec">/etc/samba/scripts/autopoweruser.sh %U %m</smbconfoption>
<smbconfoption name="read only">Yes</smbconfoption>
<smbconfoption name="guest ok">Yes</smbconfoption>
</smbconfblock>
</example>

		<step><para>
		Ensure that every Windows workstation Adminsitrator account has the same password that you
		have used in the script shown in <link linkend="magicnetlogon">the Netlogon Example smb.conf
		file</link>
		</para></step>

</procedure>

	<para>
	This script will be executed every time a user logs onto the network. Therefore every user will
	have local Windows workstation management rights. This could of course be assigned using a group,
	in which case there is little justification for the use of this procedure. The key justification
	for the use of this method is that it will guarantee that all users have appropriate rights on
	the workstation.
	</para>

	</sect3>

	</sect2>

	</sect1>

	<sect1>
	<title>UNIX and Windows User Management</title>

	<para>
<indexterm><primary>user account</primary></indexterm>
<indexterm><primary>UNIX/Linux user account</primary></indexterm>
<indexterm><primary>UID</primary></indexterm>
<indexterm><primary>POSIX account</primary></indexterm>
<indexterm><primary>range</primary></indexterm>
<indexterm><primary>Windows user accounts</primary></indexterm>
<indexterm><primary>winbindd</primary></indexterm>
<indexterm><primary>account information</primary></indexterm>
	Every Windows network user account must be translated to a UNIX/Linux user account. In actual fact,
	the only account information the UNIX/Linux Samba server needs is a UID.  The UID is available either
	from a system (POSIX) account or from a pool (range) of UID numbers that is set aside for the purpose
	of being allocated for use by Windows user accounts. In the case of the UID pool, the UID for a
	particular user will be allocated by <command>winbindd</command>.
	</para>

	<para>
	Although this is not the appropriate place to discuss the <smbconfoption name="username map"/> facility,
	this interface is an important method of mapping a Windows user account to a UNIX account that has a
	different name. Refer to the man page for the &smb.conf; file for more information regarding this
	facility. User name mappings cannot be managed using the <command>net</command> utility.
	</para>

	<sect2 id="sbeuseraddn">
	<title>Adding User Accounts</title>

	<para>
	The syntax for adding a user account via the <command>net</command> (according to the man page) is shown
	here:
<screen>
net [&lt;method&gt;] user ADD &lt;name&gt; [-c container] [-F user flags] \
    [misc. options] [targets]
</screen>
	The user account password may be set using this syntax:
<screen>
net rpc password &lt;username&gt; [&lt;password&gt;] -Uadmin_username%admin_pass
</screen>
	</para>

	<para>
	The following demonstrates the addition of an account to the server <constant>FRODO</constant>:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>user add</tertiary></indexterm>
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>user password</tertiary></indexterm>
<screen>
&rootprompt; net rpc user add jacko -S FRODO -Uroot%not24get
Added user jacko
</screen>
	The account password can be set with the following methods (all show the same operation):
<screen>
&rootprompt; net rpc password jacko f4sth0rse -S FRODO -Uroot%not24get
&rootprompt; net rpc user password jacko f4sth0rse \
    -S FRODO -Uroot%not24get
</screen>
	</para>

	</sect2>

	<sect2>
	<title>Deletion of User Accounts</title>

	<para>
	Deletion of a user account can be done using the following syntax:
<screen>
net [&lt;method&gt;] user DELETE &lt;name&gt; [misc. options] [targets]
</screen>
	The following command will delete the user account <constant>jacko</constant>:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>user delete</tertiary></indexterm>
<screen>
&rootprompt; net rpc user delete jacko -Uroot%not24get
Deleted user account
</screen>
	</para>

	</sect2>

	<sect2>
	<title>Managing User Accounts</title>

	<para>
	Two basic user account operations are routinely used: change of password and querying which groups a user
	is a member of. The change of password operation is shown in <link linkend="sbeuseraddn"/>.
	</para>

	<para>
	The ability to query Windows group membership can be essential. Here is how a remote server may be
	interrogated to find which groups a user is a member of:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>user info</tertiary></indexterm>
<screen>
&rootprompt; net rpc user info jacko -S SAURON -Uroot%not24get
net rpc user info jacko -S SAURON -Uroot%not24get
Domain Users
Domain Admins
Engineers
TorridGroup
BOP Shop
Emergency Services
</screen>
	</para>

	</sect2>

	<sect2>
	<title>User Mapping</title>

	<para>
<indexterm><primary>logon name</primary></indexterm>
<indexterm><primary>/etc/samba/smbusers</primary></indexterm>
<indexterm><primary>username map</primary></indexterm>
	In some situations it is unavoidable that a user's Windows logon name will differ from the login ID
	that user has on the Samba server. It is possible to create a special file on the Samba server that
	will permit the Windows user name to be mapped to a different UNIX/Linux user name. The &smb.conf;
	file must also be amended so that the <constant>[global]</constant> stanza contains the parameter:
<screen>
username map = /etc/samba/smbusers
</screen>
	The content of the <filename>/etc/samba/smbusers</filename> file is shown here:
<screen>
parsonsw: "William Parsons"
marygee: geeringm
</screen>
	In this example the Windows user account <quote>William Parsons</quote> will be mapped to the UNIX user
	<constant>parsonsw</constant>, and the Windows user account <quote>geeringm</quote> will be mapped to the
	UNIX user <constant>marygee</constant>.
	</para>

	</sect2>

	</sect1>

	<sect1>
	<title>Administering User Rights and Privileges</title>

	<para>
<indexterm><primary>credentials</primary></indexterm>
<indexterm><primary>manage printers</primary></indexterm>
<indexterm><primary>manage shares</primary></indexterm>
<indexterm><primary>manage groups</primary></indexterm>
<indexterm><primary>manage users</primary></indexterm>
	With all versions of Samba earlier than 3.0.11 the only account on a Samba server that could
	manage users, groups, shares, printers, and such was the <constant>root</constant> account. This caused
	problems for some users and was a frequent source of scorn over the necessity to hand out the
	credentials for the most security-sensitive account on a UNIX/Linux system.
	</para>

	<para>
<indexterm><primary>delegate administrative privileges</primary></indexterm>
<indexterm><primary>normal user</primary></indexterm>
<indexterm><primary>rights and privilege</primary></indexterm>
<indexterm><primary>privilege management</primary></indexterm>
<indexterm><primary>groups of users</primary></indexterm>
	New to Samba version 3.0.11 is the ability to delegate administrative privileges as necessary to either
	a normal user or to groups of users. The significance of the administrative privileges is documented
	in <link linkend="rights"/>. Examples of use of the <command>net</command> for user rights and privilege
	management is appropriate to this chapter.
	</para>

	<note><para>
	When user rights and privileges are correctly set, there is no longer a need for a Windows
	network account for the <constant>root</constant> user (nor for any synonym of it) with a UNIX UID=0.
	Initial user rights and privileges can be assigned by any account that is a member of the <constant>
	Domain Admins</constant> group. Rights can be assigned to user as well as group accounts.
	</para></note>

	<para>
	By default, no privileges and rights are assigned. This is demonstrated by executing the command
	shown here:
<screen>
&rootprompt; net rpc rights list accounts -U root%not24get
BUILTIN\Print Operators
No privileges assigned

BUILTIN\Account Operators
No privileges assigned

BUILTIN\Backup Operators
No privileges assigned

BUILTIN\Server Operators
No privileges assigned

BUILTIN\Administrators
No privileges assigned

Everyone
No privileges assigned
</screen>
	</para>

	<para>
	The <command>net</command> command can be used to obtain the currently supported capabilities for rights
	and privileges using this method:
<indexterm><primary>SeMachineAccountPrivilege</primary></indexterm>
<indexterm><primary>SePrintOperatorPrivilege</primary></indexterm>
<indexterm><primary>SeAddUsersPrivilege</primary></indexterm>
<indexterm><primary>SeRemoteShutdownPrivilege</primary></indexterm>
<indexterm><primary>SeDiskOperatorPrivilege</primary></indexterm>
<indexterm><primary>SeBackupPrivilege</primary></indexterm>
<indexterm><primary>SeRestorePrivilege</primary></indexterm>
<indexterm><primary>SeTakeOwnershipPrivilege</primary></indexterm>
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>rights list</tertiary></indexterm>
<screen>
&rootprompt; net rpc rights list -U root%not24get
     SeMachineAccountPrivilege  Add machines to domain
      SePrintOperatorPrivilege  Manage printers
           SeAddUsersPrivilege  Add users and groups to the domain
     SeRemoteShutdownPrivilege  Force shutdown from a remote system
       SeDiskOperatorPrivilege  Manage disk shares
             SeBackupPrivilege  Back up files and directories
            SeRestorePrivilege  Restore files and directories
      SeTakeOwnershipPrivilege  Take ownership of files or other objects
</screen>
	Machine account privilege is necessary to permit a Windows NT4 or later network client to be added to the
	domain. The disk operator privilege is necessary to permit the user to manage share ACLs and file and
	directory ACLs for objects not owned by the user.
	</para>

	<para>
	For reference purposes, a Windows 2000 Domain Controller reports that it supports the following
	privileges:
<screen>
         SeCreateTokenPrivilege  Create a token object
  SeAssignPrimaryTokenPrivilege  Replace a process level token
          SeLockMemoryPrivilege  Lock pages in memory
       SeIncreaseQuotaPrivilege  Increase quotas
      SeMachineAccountPrivilege  Add workstations to domain
                 SeTcbPrivilege  Act as part of the operating system
            SeSecurityPrivilege  Manage auditing and security log
       SeTakeOwnershipPrivilege  Take ownership of files or other objects
          SeLoadDriverPrivilege  Load and unload device drivers
       SeSystemProfilePrivilege  Profile system performance
          SeSystemtimePrivilege  Change the system time
SeProfileSingleProcessPrivilege  Profile single process
SeIncreaseBasePriorityPrivilege  Increase scheduling priority
      SeCreatePagefilePrivilege  Create a pagefile
     SeCreatePermanentPrivilege  Create permanent shared objects
              SeBackupPrivilege  Back up files and directories
             SeRestorePrivilege  Restore files and directories
            SeShutdownPrivilege  Shut down the system
               SeDebugPrivilege  Debug programs
               SeAuditPrivilege  Generate security audits
   SeSystemEnvironmentPrivilege  Modify firmware environment values
        SeChangeNotifyPrivilege  Bypass traverse checking
      SeRemoteShutdownPrivilege  Force shutdown from a remote system
              SeUndockPrivilege  Remove computer from docking station
           SeSyncAgentPrivilege  Synchronize directory service data
    SeEnableDelegationPrivilege  Enable computer and user accounts to
                                 be trusted for delegation
        SeManageVolumePrivilege  Perform volume maintenance tasks
         SeImpersonatePrivilege  Impersonate a client after authentication
        SeCreateGlobalPrivilege  Create global objects
</screen>
	The Samba Team are implementing only those privileges that are logical and useful in the UNIX/Linux
	envronment. Many of the Windows 200X/XP privileges have no direct equivalence in UNIX.
	</para>

	<para>
	In this example, all rights are assigned to the <constant>Domain Admins</constant> group. This is a good
	idea since members of this group are generally expected to be all-powerful. This assignment makes that
	the reality:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>rights grant</tertiary></indexterm>
<screen>
&rootprompt; net rpc rights grant "MIDEARTH\Domain Admins" \
    SeMachineAccountPrivilege SePrintOperatorPrivilege \
    SeAddUsersPrivilege SeRemoteShutdownPrivilege \
    SeDiskOperatorPrivilege  -U root%not24get
Successfully granted rights.
</screen>
	Next, the domain user <constant>jht</constant> is given the privileges needed for day-to-day
	administration:
<screen>
&rootprompt; net rpc rights grant "MIDEARTH\jht" \
    SeMachineAccountPrivilege SePrintOperatorPrivilege \
    SeAddUsersPrivilege SeDiskOperatorPrivilege \
    -U root%not24get
Successfully granted rights.
</screen>
	</para>

	<para>
	The following step permits validation of the changes just made:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>rights list accounts</tertiary></indexterm>
<screen>
&rootprompt; net rpc rights list accounts -U root%not24get
MIDEARTH\jht
SeMachineAccountPrivilege
SePrintOperatorPrivilege
SeAddUsersPrivilege
SeDiskOperatorPrivilege

BUILTIN\Print Operators
No privileges assigned

BUILTIN\Account Operators
No privileges assigned

BUILTIN\Backup Operators
No privileges assigned

BUILTIN\Server Operators
No privileges assigned

BUILTIN\Administrators
No privileges assigned

Everyone
No privileges assigned

MIDEARTH\Domain Admins
SeMachineAccountPrivilege
SePrintOperatorPrivilege
SeAddUsersPrivilege
SeRemoteShutdownPrivilege
SeDiskOperatorPrivilege
</screen>
	</para>

	</sect1>

	<sect1>
	<title>Managing Trust Relationships</title>

	<para>
	There are essentially two types of trust relationships: the first is between domain controllers and domain
	member machines (network clients), the second is between domains (called interdomain trusts). All
	Samba servers that participate in domain security require a domain membership trust account, as do like
	Windows NT/200x/XP workstations.
	</para>

	<sect2>
	<title>Machine Trust Accounts</title>

	<para>
	The net command looks in the &smb.conf; file to obtain its own configuration settings. Thus, the following
	command 'know' which domain to join from the &smb.conf; file.
	</para>

	<para>
	A Samba server domain trust account can be validated as shown in this example:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>testjoin</tertiary></indexterm>
<screen>
&rootprompt; net rpc testjoin
Join to 'MIDEARTH' is OK
</screen>
	Where there is no domain membership account, or when the account credentials are not valid, the following
	results will be observed:
<screen>
net rpc testjoin -S DOLPHIN
Join to domain 'WORLDOCEAN' is not valid
</screen>
	</para>

	<para>
	The equivalent command for joining a Samba server to a Windows ADS domain is shown here:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>testjoin</tertiary></indexterm>
<screen>
&rootprompt; net ads testjoin
Using short domain name -- TAKEAWAY
Joined 'LEMONADE' to realm 'TAKEAWAY.BIZ'
</screen>
	In the event that the ADS trust was not established, or is broken for one reason or another, the following
	error message may be obtained:
<screen>
&rootprompt; net ads testjoin -UAdministrator%secret
Join to domain is not valid
</screen>
	</para>

	<para>
	The following demonstrates the process of creating a machine trust account in the target domain for the
	Samba server from which the command is executed:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm>
<screen>
&rootprompt; net rpc join -S FRODO -Uroot%not24get
Joined domain MIDEARTH.
</screen>
	The joining of a Samba server to a Samba domain results in the creation of a machine account. An example
	of this is shown here:
<screen>
&rootprompt; pdbedit -Lw merlin\$
merlin$:1009:9B4489D6B90461FD6A3EC3AB96147E16:\
176D8C554E99914BDF3407DEA2231D80:[S          ]:LCT-42891919:
</screen>
	The S in the square brackets means this is a server (PDC/BDC) account. The domain join can be cast to join
	purely as a workstation, in which case the S is replaced with a W (indicating a workstation account). The
	following command can be used to affect this:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join member</tertiary></indexterm>
<screen>
&rootprompt; net rpc join member -S FRODO -Uroot%not24get
Joined domain MIDEARTH.
</screen>
	Note that the command-line parameter <constant>member</constant> makes this join specific. By default
	the type is deduced from the &smb.conf; file configuration. To specifically join as a PDC or BDC, the
	command-line parameter will be <constant>[PDC | BDC]</constant>. For example:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join bdc</tertiary></indexterm>
<screen>
&rootprompt; net rpc join bdc -S FRODO -Uroot%not24get
Joined domain MIDEARTH.
</screen>
	It is best to let Samba figure out the domain join type from the settings in the &smb.conf; file.
	</para>

	<para>
	The command to join a Samba server to a Windows ADS domain is shown here:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>join</tertiary></indexterm>
<screen>
&rootprompt; net ads join -UAdministrator%not24get
Using short domain name -- GDANSK
Joined 'FRANDIMITZ' to realm 'GDANSK.ABMAS.BIZ'
</screen>
	</para>

	<para>
	There is no specific option to remove a machine account from an NT4 domain. When a domain member that is a
	Windows machine is withdrawn from the domain, the domain membership account is not automatically removed
	either. Inactive domain member accounts can be removed using any convenient tool. If necessary, the
	machine account can be removed using the following <command>net</command> command:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>user delete</tertiary></indexterm>
<screen>
&rootprompt; net rpc user delete HERRING\$ -Uroot%not24get
Deleted user account.
</screen>
	The removal is made possible because machine accounts are just like user accounts with a trailing $
	character. The account management operations treat user and machine accounts in like manner.
	</para>

	<para>
	A Samba-3 server that is a Windows ADS domain member can execute the following command to detach from the
	domain:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>leave</tertiary></indexterm>
<screen>
&rootprompt; net ads leave
</screen>
	</para>

	<para>
	Detailed information regarding an ADS domain can be obtained by a Samba DMS machine by executing the
	following:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>status</tertiary></indexterm>
<screen>
&rootprompt; net ads status
</screen>
	The volume of information is extensive. Please refer to the book <quote>Samba-3 by Example</quote>,
	Chapter 7 for more information regarding its use. This book may be obtained either in print or online from
	the <ulink url="http://www.samba.org/samba/docs/Samba3-ByExample.pdf">Samba-3 by Example</ulink>.
	</para>

	</sect2>

	<sect2>
	<title>Interdomain Trusts</title>

	<para>
	Interdomain trust relationships form the primary mechanism by which users from one domain can be granted
	access rights and privileges in another domain. 
	</para>

	<para>
	To discover what trust relationships are in effect, execute this command:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>trustdom list</tertiary></indexterm>
<screen>
&rootprompt; net rpc trustdom list -Uroot%not24get
Trusted domains list:

none

Trusting domains list:

none
</screen>
	There are no interdomain trusts at this time; the following steps will create them.
	</para>

	<para>
	It is necessary to create a trust account in the local domain. A domain controller in a second domain can
	create a trusted connection with this account. That means that the foreign domain is being trusted
	to access resources in the local domain. This command creates the local trust account:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>trustdom add</tertiary></indexterm>
<screen>
&rootprompt; net rpc trustdom add DAMNATION f00db4r -Uroot%not24get
</screen>
	The account can be revealed by using the <command>pdbedit</command> as shown here:
<screen>
&rootprompt; pdbedit -Lw DAMNATION\$
DAMNATION$:1016:9AC1F121DF897688AAD3B435B51404EE: \
7F845808B91BB9F7FEF44B247D9DC9A6:[I         ]:LCT-428934B1:
</screen>
	A trust account will always have an I in the field within the square brackets.
	</para>

	<para>
	If the trusting domain is not capable of being reached, the following command will fail:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>trustdom list</tertiary></indexterm>
<screen>
&rootprompt; net rpc trustdom list -Uroot%not24get
Trusted domains list:

none

Trusting domains list:

DAMNATION           S-1-5-21-1385457007-882775198-1210191635
</screen>
	The above command executed successfully; a failure is indicated when the following response is obtained:
<screen>
net rpc trustdom list -Uroot%not24get
Trusted domains list:

DAMNATION           S-1-5-21-1385457007-882775198-1210191635

Trusting domains list:

DAMNATION           domain controller is not responding
</screen>
	</para>

	<para>
	Where a trust account has been created on a foreign domain, Samba is able to establish the trust (connect with)
	the foreign account. In the process it creates a one-way trust to the resources on the remote domain. This
	command achieves the objective of joining the trust relationship:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>trustdom establish</tertiary></indexterm>
<screen>
&rootprompt; net rpc trustdom establish DAMNATION
Password: xxxxxxx	== f00db4r
Could not connect to server TRANSGRESSION
Trust to domain DAMNATION established
</screen>
	Validation of the two-way trust now established is possible as shown here:
<screen>
&rootprompt; net rpc trustdom list -Uroot%not24get
Trusted domains list:

DAMNATION           S-1-5-21-1385457007-882775198-1210191635

Trusting domains list:

DAMNATION           S-1-5-21-1385457007-882775198-1210191635
</screen>
	</para>

	<para>
	Sometimes it is necessary to remove the ability for local users to access a foreign domain. The trusting
	connection can be revoked as shown here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>trustdom revoke</tertiary></indexterm>
<screen>
&rootprompt; net rpc trustdom revoke DAMNATION -Uroot%not24get
</screen>
	At other times it becomes necessary to remove the ability for users from a foreign domain to be able to
	access resources in the local domain. The command shown here will do that:
<screen>
&rootprompt; net rpc trustdom del DAMNATION -Uroot%not24get
</screen>

	</para>

	</sect2>

	</sect1>

	<sect1>
	<title>Managing Security Identifiers (SIDS)</title>

	<para>
<indexterm><primary>security identifier</primary></indexterm>
<indexterm><primary>SID</primary></indexterm>
<indexterm><primary>desktop profiles</primary></indexterm>
<indexterm><primary>user encoded</primary></indexterm>
<indexterm><primary>group SID</primary></indexterm>
	The basic security identifier that is used by all Windows networking operations is the Windows security
	identifier (SID). All Windows network machines (servers and workstations), users, and groups are
	identified by their respective SID. All desktop profiles are also encoded with user and group SIDs that
	are specific to the SID of the domain to which the user belongs.
	</para>

	<para>
<indexterm><primary>machine SID</primary></indexterm>
<indexterm><primary>domain SID</primary></indexterm>
<indexterm><primary>SID</primary></indexterm>
<indexterm><primary>rejoin</primary></indexterm>
	It is truly prudent to store the machine and/or domain SID in a file for safekeeping. Why? Because 
	a change in hostname or in the domain (workgroup) name may result in a change in the SID. When you
	have the SID on hand, it is a simple matter to restore it. The alternative is to suffer the pain of
	having to recover user desktop profiles and perhaps rejoin all member machines to the domain.
	</para>

	<para>
	First, do not forget to store the local SID in a file. It is a good idea to put this in the directory
	in which the &smb.conf; file is also stored. Here is a simple action to achieve this:
<indexterm><primary>net</primary><secondary>getlocalsid</secondary></indexterm>
<screen>
&rootprompt; net getlocalsid > /etc/samba/my-sid
</screen>
	Good, there is now a safe copy of the local machine SID. On a PDC/BDC this is the domain SID also.
	</para>

	<para>
	The following command reveals what the former one should have placed into the file called
	<filename>my-sid</filename>:
<screen>
&rootprompt; net getlocalsid
SID for domain MERLIN is: S-1-5-21-726309263-4128913605-1168186429
</screen>
	</para>

	<para>
	If ever it becomes necessary to restore the SID that has been stored in the <filename>my-sid</filename>
	file, simply copy the SID (the string of characters that begins with <constant>S-1-5-21</constant>) to
	the command line shown here:
<indexterm><primary>net</primary><secondary>setlocalsid</secondary></indexterm>
<screen>
&rootprompt; net setlocalsid S-1-5-21-1385457007-882775198-1210191635
</screen>
	Restoration of a machine SID is a simple operation, but the absence of a backup copy can be very
	problematic.
	</para>

	<para>
	The following operation is useful only for machines that are being configured as a PDC or a BDC.
	DMS and workstation clients should have their own machine SID to avoid
	any potential namespace collision. Here is the way that the BDC SID can be synchronized to that
	of the PDC (this is the default NT4 domain practice also):
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>getsid</tertiary></indexterm>
<screen>
&rootprompt; net rpc getsid -S FRODO -Uroot%not24get
Storing SID S-1-5-21-726309263-4128913605-1168186429 \
    for Domain MIDEARTH in secrets.tdb
</screen>
	Usually it is not necessary to specify the target server (-S FRODO) or the administrator account
	credentials (-Uroot%not24get).
	</para>

	</sect1>
	
	<sect1>
	<title>Share Management</title>

	<para>
	Share management is central to all file serving operations. Typical share operations include:
	</para>

	<itemizedlist>
		<listitem><para>Creation/change/deletion of shares</para></listitem>
		<listitem><para>Setting/changing ACLs on shares</para></listitem>
		<listitem><para>Moving shares from one server to another</para></listitem>
		<listitem><para>Change of permissions of share contents</para></listitem>
	</itemizedlist>

	<para>
	Each of these are dealt with here insofar as they involve the use of the <command>net</command>
	command. Operations outside of this command are covered elsewhere in this document.
	</para>

	<sect2>
	<title>Creating, Editing, and Removing Shares</title>

	<para>
	A share can be added using the <command>net rpc share</command> command capabilities.
	The target machine may be local or remote and is specified by the -S option. It must be noted
	that the addition and deletion of shares using this tool depends on the availability of a suitable
	interface script. The interface scripts Sambas <command>smbd</command> uses are called
	<smbconfoption name="add share script"/> and <smbconfoption name="delete share script"/>.
	A set of example scripts are provided in the Samba source code tarball in the directory
	<filename>~samba/examples/scripts</filename>.
	</para>

	<para>
	The following steps demonstrate the use of the share management capabilities of the <command>net</command>
	utility. In the first step a share called <constant>Bulge</constant> is added. The sharepoint within the
	file system is the directory <filename>/data</filename>. The command that can be executed to perform the
	addition of this share is shown here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>share add</tertiary></indexterm>
<screen>
&rootprompt; net rpc share add Bulge=/data -S MERLIN -Uroot%not24get
</screen>
	Validation is an important process, and by executing the command <command>net rpc share</command>
	with no other operators it is possible to obtain a listing of available shares, as shown here:
<screen>
&rootprompt; net rpc share -S MERLIN -Uroot%not24get
profdata
archive
Bulge   &lt;--- This one was added
print$
netlogon
profiles
IPC$
kyocera
ADMIN$
</screen>
	</para>

	<para>
	Often it is desirable also to permit a share to be removed using a command-line tool.
	The following step permits the share that was previously added to be removed:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>share delete</tertiary></indexterm>
<screen>
&rootprompt; net rpc share delete Bulge -S MERLIN -Uroot%not24get
</screen>
	A simple validation shown here demonstrates that the share has been removed:
<screen>
&rootprompt; net rpc share -S MERLIN -Uroot%not24get
profdata
archive
print$
netlogon
profiles
IPC$
ADMIN$
kyocera
</screen>
	</para>

	</sect2>

	<sect2>
	<title>Creating and Changing Share ACLs</title>

	<para>
	At this time the <command>net</command> tool cannot be used to manage ACLs on Samba shares. In MS Windows 
	language this is called Share Permissions.
	</para>

	<para>
	It is possible to set ACLs on Samba shares using either the SRVTOOLS NT4 Domain Server Manager
	or using the Computer Management MMC snap-in. Neither is covered here,
	but see <link linkend="AccessControls"/>.
	</para>

	</sect2>

	<sect2>
	<title>Share, Directory, and File Migration</title>

	<para>
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>vampire</tertiary></indexterm>
	Shares and files can be migrated in the same manner as user, machine, and group accounts.
	It is possible to preserve access control settings (ACLs) as well as security settings
	throughout the migration process. The <command>net rpc vampire</command> facility is used
	to migrate accounts from a Windows NT4 (or later) domain to a Samba server. This process
	preserves passwords and account security settings and is a precursor to the migration
	of shares and files.
	</para>

	<para>
	The <command>net rpc share</command> command may be used to migrate shares, directories,
	files, printers, and all relevant data from a Windows server to a Samba server.
	</para>

	<para>
	A set of command-line switches permit the creation of almost direct clones of Windows file
	servers. For example, when migrating a fileserver, file ACLs and DOS file attributes from
	the Windows server can be included in the migration process and will reappear, almost identically,
	on the Samba server when the migration has been completed.
	</para>

	<para>
	The migration process can be completed only with the Samba server already being fully operational.
	The user and group accounts must be migrated before attempting to migrate data
	share, files, and printers. The migration of files and printer configurations involves the use
	of both SMB and MS DCE RPC services. The benefit of the manner in which the migration process has
	been implemented is that the possibility now exists to use a Samba server as a man-in-middle migration
	service that affects a transfer of data from one server to another. For example, if the Samba
	server is called MESSER, the source Windows NT4 server is called PEPPY, and the target Samba
	server is called GONZALES, the machine MESSER can be used to effect the migration of all data
	(files and shares) from PEPPY to GONZALES. If the target machine is not specified, the local
	server is assumed by default.
	</para>

	<para>
	The success of server migration requires a firm understanding of the structure of the source
	server (or domain) as well as  the processes on which the migration is critically dependant.
	</para>

	<para>
	There are two known limitations to the migration process:
	</para>

	<orderedlist>
		<listitem><para>
		The <command>net</command> command requires that the user credentials provided exist on both
		the migration source and the migration target.
		</para></listitem>

		<listitem><para>
		Printer settings may not be fully or may be incorrectly migrated. This might in particular happen
		when migrating a Windows 2003 print server to Samba.
		</para></listitem>
	</orderedlist>

	<sect3>
	<title>Share Migration</title>

	<para>
	The <command>net rpc share migrate</command> command operation permits the migration of plain
	share stanzas. A stanza contains the parameters within which a file or print share are defined.
	The use of this migration method will create share stanzas that have as parameters the file
	system directory path, an optional description, and simple security settings that permit write
	access to files. One of the first steps necessary following migration is to review the share
	stanzas to ensure that the settings are suitable for use.
	</para>

	<para>
	The shares are created on the fly as part of the migration process. The <command>smbd</command>
	application does this by calling on the operating system to execute the script specified by the 
	&smb.conf; parameter <parameter>add share command</parameter>.
	</para>

	<para>
	There is a suitable example script for the <parameter>add share command</parameter> in the
	<filename>$SAMBA_SOURCES/examples/scripts</filename> directory. It should be noted that
	the account that is used to drive the migration must, of necessity, have appropriate file system
	access privileges and have the right to create shares and to set ACLs on them. Such rights are
	conferred by these rights: <parameter>SeAddUsersPrivilege</parameter> and <parameter>SeDiskOperatorPrivilege</parameter>.
	For more information regarding rights and privileges please refer to <link linkend="rights"/>.
	</para>

	<para>
	The syntax of the share migration command is shown here:
<screen>
net rpc share MIGRATE SHARES &lt;share-name&gt; -S &lt;source&gt;
        [--destination=localhost] [--exclude=share1,share2] [-v]
</screen>
	When the parameter &lt;share-name&gt; is omitted, all shares will be migrated. The potentially
	large list of available shares on the system that is being migrated can be limited using the
	<parameter>--exclude</parameter> switch. For example:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>share migrate</tertiary></indexterm>
<screen>
&rootprompt; net rpc share migrate shares myshare\
         -S win2k -U administrator%secret"
</screen>
	This will migrate the share <constant>myshare</constant> from the server <constant>win2k</constant>
	to the Samba Server using the permissions that are tied to the account <constant>administrator</constant> 
	with the password <constant>secret</constant>. The account that is used must be the same on both the
	migration source server and the target Samba server. The use of the <command>net rpc
	vampire</command>, prior to attempting the migration of shares, will ensure that accounts will be
	identical on both systems. One precaution worth taking before commencement of migration of shares is
	to validate that the migrated accounts (on the Samba server) have the needed rights and privileges.
	This can be done as shown here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>right list accounts</tertiary></indexterm>
<screen>
&rootprompt; net rpc right list accounts -Uroot%not24get
</screen>
	The steps taken so far perform only the migration of shares. Directories and directory contents
	are not migrated by the steps covered up to this point.
	</para>

	</sect3>

	<sect3>
	<title>File and Directory Migration</title>

	<para>
	Everything covered to this point has been done in preparation for the migration of file and directory
	data. For many people preparation is potentially boring and the real excitement only begins when file
	data can be used. The next steps demonstrate the techniques that can be used to transfer (migrate)
	data files using the <command>net</command> command.
	</para>

	<para>
	Transfer of files from one server to another has always been a challenge for MS Windows
	administrators because Windows NT and 200X servers do not include the tools needed. The
	<command>xcopy</command> is not capable of preserving file and directory ACLs. Microsoft does provide a
	utility that can copy ACLs (security settings) called <command>scopy</command>, but it is provided only
	as part of the Windows NT or 200X Server Resource Kit.
	</para>

	<para>
	There are several tools, both commercial and freeware, that can be used from a Windows server to copy files
	and directories with full preservation of security settings. One of the best known of the free tools is
	called <command>robocopy</command>.
	</para>

	<para>
	The <command>net</command> utility can be used to copy files and directories with full preservation of
	ACLs as well as DOS file attributes. Note that including ACLs makes sense only where the destination
	system will operate within the same security context as the source system. This applies both to a
	DMS and to domain controllers that result from a vampired domain.
	Before file and directory migration, all shares must already exist.
	</para>

	<para>
	The syntax for the migration commands is shown here:
<screen>
net rpc share MIGRATE FILES &lt;share-name&gt; -S &lt;source&gt;
    [--destination=localhost] [--exclude=share1,share2]
    [--acls] [--attrs] [--timestamps] [-v]
</screen>
	If the &lt;share-name&gt; parameter is omitted, all shares will be migrated. The potentially large
	list of shares on the source system can be restricted using the <parameter>--exclude</parameter> command
	switch.
	</para>

	<para>
	Where it is necessary to preserve all file ACLs, the <parameter>--acls</parameter> switch should be added
	to the above command line. Original file timestamps can be preserved by specifying the
	<parameter>--timestamps</parameter> switch, and the DOS file attributes (i.e., hidden, archive, etc.) can
	be preserved by specifying the <parameter>--attrs</parameter> switch.
	</para>

	<note><para>
	The ability to preserve ACLs depends on appropriate support for ACLs as well as the general file system
	semantics of the host operating system on the target server. A migration from one Windows file server to
	another will perfectly preserve all file attributes. Because of the difficulty of mapping Windows ACLs
	onto a POSIX ACLs-supporting system, there can be no perfect migration of Windows ACLs to a Samba server.
	</para></note>

	<para>
	The ACLs that result on a Samba server will most probably not match the originating ACLs. Windows supports
	the possibility of files that are owned only by a group. Group-alone file ownership is not possible under
	UNIX/Linux. Errors in migrating group-owned files can be avoided by using the &smb.conf; file
	<smbconfoption name="force unknown acl user">yes</smbconfoption> parameter. This facility will
	automatically convert group-owned files into correctly user-owned files on the Samba server.
	</para>

	<para>
	An example for migration of files from a machine called <constant>nt4box</constant> to the Samba server
	from which the process will be handled is shown here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>share migrate files</tertiary></indexterm>
<screen>
&rootprompt; net rpc share migrate files -S nt4box --acls \
    --attrs -U administrator%secret
</screen>
	</para>

	<para>
	This command  will migrate all files and directories from all file shares on the Windows server called
	<constant>nt4box</constant> to the Samba server from which migration is initiated. Files that are group-owned
	will be owned by the user account <constant>administrator</constant>.
	</para>

	</sect3>

	<sect3>
	<title>Simultaneous Share and File Migration</title>

	<para>
	The operating mode shown here is just a combination of the previous two. It first migrates
	share definitions and then all shared files and directories:
<screen>
net rpc share MIGRATE ALL &lt;share-name&gt; -S &lt;source&gt;
    [--exclude=share1, share2] [--acls] [--attrs] [--timestamps] [-v]
</screen>
	</para>

	<para>
	An example of simultaneous migration is shown here:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>share migrate all</tertiary></indexterm>
<screen>
&rootprompt; net rpc share migrate all -S w2k3server -U administrator%secret
</screen>
	This will generate a complete server clone of the <parameter>w2k3server</parameter> server.
	</para>

	</sect3>

	</sect2>

	<sect2>
	<title>Printer Migration</title>

	<para>
	The installation of a new server, as with the migration to a new network environment, often is similar to
	building a house; progress is very rapid from the laying of foundations up to the stage at which
	the the house can be locked up, but the finishing off appears to take longer and longer as building
	approaches completion.
	</para>

	<para>
	Printing needs vary greatly depending on the network environment and may be very simple or complex. If
	the need is very simple, the best solution to the implementation of printing support may well be to
	re-install everything from a clean slate instead of migrating older configurations. On the other hand,
	a complex network that is integrated with many international offices and a multiplexity of local branch
	offices, each of which form an inter-twined maze of printing possibilities, the ability to migrate all
	printer configurations is decidedly beneficial. To manually re-establish a complex printing network
	will take much time and frustration. Often it will not be possible to find driver files that are
	currently in use, necessitating the installation of newer drivers. Newer drivers often implement
	printing features that will necessitate a change in the printer usage. Additionally, with very complex
	printer configurations it becomes almost impossible to re-create the same environment &smbmdash; no matter
	how extensively it has been documented.
	</para>

	<para>
	The migration of an existing printing architecture involves the following:
	</para>

	<itemizedlist>
		<listitem><para>Establishment of print queues.</para></listitem>

		<listitem><para>Installation of printer drivers (both for the print server and for Windows clients.</para></listitem>

		<listitem><para>Configuration of printing forms.</para></listitem>

		<listitem><para>Implementation of security settings.</para></listitem>

		<listitem><para>Configuration of printer settings.</para></listitem>
	</itemizedlist>

	<para>
	The Samba <command>net</command> utility permits printer migration from one Windows print server
	to another. When this tool is used to migrate printers to a Samba server <command>smbd</command>,
	the application that receives the network requests to create the necessary services must call out
	to the operating system in order to create the underlying printers. The call-out is implemented
	by way of an interface script that can be specified by the &smb.conf; file parameter
	<smbconfoption id="add printer script"/>. This script is essential to the migration process.
	A suitable example script may be obtained from the <filename>$SAMBA_SOURCES/examples/scripts</filename>
	directory. Take note that this script must be customized to suit the operating system environment
	and may use its tools to create a print queue.
	</para>

	<para>
	Each of the components listed above can be completed separately, or they can be completed as part of an
	automated operation. Many network administrators prefer to deal with migration issues in a manner that
	gives them the most control, particularly when things go wrong. The syntax for each operation is now
	briefly described.
	</para>

	<para>
	Printer migration from a Windows print server (NT4 or 200x) is shown. This instruction causes the
	printer share to be created together with the underlying print queue:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>printer migrate printers</tertiary></indexterm>
<screen>
net rpc printer MIGRATE PRINTERS [printer] [misc. options] [targets]
</screen>
	Printer drivers can be migrated from the Windows print server to the Samba server using this
	command-line instruction:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>printer migrate drivers</tertiary></indexterm>
<screen>
net rpc printer MIGRATE DRIVERS [printer] [misc. options] [targets]
</screen>
	Printer forms can be migrated with the following operation:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>printer migrate forms</tertiary></indexterm>
<screen>
net rpc printer MIGRATE FORMS [printer] [misc. options] [targets]
</screen>
	Printer security settings (ACLs) can be migrated from the Windows server to the Samba server using this command:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>printer migrate security</tertiary></indexterm>
<screen>
net rpc printer MIGRATE SECURITY [printer] [misc. options] [targets]
</screen>
	Printer configuration settings include factors such as paper size and default paper orientation.
	These can be migrated from the Windows print server to the Samba server with this command:
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>printer migrate settings</tertiary></indexterm>
<screen>
net rpc printer MIGRATE SETTINGS [printer] [misc. options] [targets]
</screen>
	</para>

	<para>
	Migration of printers including the above-mentioned sets of information may be completed
	with a single command using this syntax:
<screen>
net rpc printer MIGRATE ALL [printer] [misc. options] [targets]
</screen>
	</para>

	</sect2>

	</sect1>

	<sect1>
	<title>Controlling Open Files</title>

	<para>
	The man page documents the <command>net file</command> function suite, which provides the tools to
	close open files using either RAP or RPC function calls. Please refer to the man page for specific
	usage information.
	</para>

	</sect1>

	<sect1>
	<title>Session and Connection Management</title>

	<para>
	The session management interface of the <command>net session</command> command uses the old RAP
	method to obtain the list of connections to the Samba server, as shown here:
<indexterm><primary>net</primary><secondary>rap</secondary><tertiary>session</tertiary></indexterm>
<screen>
&rootprompt; net rap session -S MERLIN -Uroot%not24get
Computer             User name            Client Type        Opens Idle time
------------------------------------------------------------------------------
\\merlin             root                 Unknown Client         0 00:00:00
\\marvel             jht                  Unknown Client         0 00:00:00
\\maggot             jht                  Unknown Client         0 00:00:00
\\marvel             jht                  Unknown Client         0 00:00:00
</screen>
	</para>

	<para>
	A session can be closed by executing a command as shown here:
<screen>
&rootprompt; net rap session close marvel -Uroot%not24get
</screen>
	</para>

	</sect1>

	<sect1>
	<title>Printers and ADS</title>

	<para>
	When Samba-3 is used within an MS Windows ADS environment, printers shared via Samba will not be browseable
	until they have been published to the ADS domain. Information regarding published printers may be obtained
	from the ADS server by executing the <command>net ads print info</command> command following this syntax:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>printer info</tertiary></indexterm>
<screen>
net ads printer info &lt;printer_name&gt; &lt;server_name&gt; -Uadministrator%secret
</screen>
	If the asterisk (*) is used in place of the printer_name argument, a list of all printers will be
	returned.
	</para>

	<para>
	To publish (make available) a printer to ADS, execute the following command:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>printer publish</tertiary></indexterm>
<screen>
net ads printer publish &lt;printer_name&gt; -Uadministrator%secret
</screen>
	This publishes a printer from the local Samba server to ADS.
	</para>

	<para>
	Removal of a Samba printer from ADS is achieved by executing this command:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>printer remove</tertiary></indexterm>
<screen>
net ads printer remove &lt;printer_name&gt; -Uadministrator%secret
</screen>
	</para>

	<para>
	A generic search (query) can also be made to locate a printer across the entire ADS domain by executing:
<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>printer search</tertiary></indexterm>
<screen>
net ads printer search &lt;printer_name&gt; -Uadministrator%secret
</screen>
	</para>

	</sect1>

	<sect1>
	<title>Manipulating the Samba Cache</title>

	<para>
	Please refer to the <command>net</command> command man page for information regarding cache management.
	</para>

	</sect1>

	<sect1 id="netmisc1">
	<title>Other Miscellaneous Operations</title>

	<para>
	The following command is useful for obtaining basic statistics regarding a Samba domain. This command does
	not work with current Windows XP Professional clients.
<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>info</tertiary></indexterm>
<screen>
&rootprompt; net rpc info
Domain Name: RAPIDFLY
Domain SID: S-1-5-21-399034208-633907489-3292421255
Sequence number: 1116312355
Num users: 720
Num domain groups: 27
Num local groups: 6
</screen>
	</para>

	<para>
	Another useful tool is the <command>net time</command> tool set. This tool may be used to query the
	current time on the target server as shown here:
<indexterm><primary>net</primary><secondary>time</secondary></indexterm>
<screen>
&rootprompt; net time -S SAURON
Tue May 17 00:50:43 2005
</screen>
	In the event that it is the intent to pass the time information obtained to the UNIX
	<command>/bin/time</command>, it is a good idea to obtain the time from the target server in a format
	that is ready to be passed through. This may be done by executing:
<indexterm><primary>net</primary><secondary>time</secondary><tertiary>system</tertiary></indexterm>
<screen>
&rootprompt; net time system -S FRODO
051700532005.16
</screen>
	The time can be set on a target server by executing:
<indexterm><primary>net</primary><secondary>time</secondary><tertiary>set</tertiary></indexterm>
<screen>
&rootprompt; net time set -S MAGGOT -U Administrator%not24get
Tue May 17 00:55:30 MDT 2005
</screen>
	It is possible to obtain the time zone of a server by executing the following command against it:
<indexterm><primary>net</primary><secondary>time</secondary><tertiary>zone</tertiary></indexterm>
<screen>
&rootprompt; net time zone -S SAURON
-0600
</screen>
	</para>

	</sect1>

</chapter>