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diff --git a/docs-xml/Samba3-HOWTO/TOSHARG-DomainMember.xml b/docs-xml/Samba3-HOWTO/TOSHARG-DomainMember.xml new file mode 100644 index 0000000000..c0f43ff130 --- /dev/null +++ b/docs-xml/Samba3-HOWTO/TOSHARG-DomainMember.xml @@ -0,0 +1,1419 @@ +<?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="domain-member"> + +<chapterinfo> + &author.jht; + &author.jeremy; + &author.jerry; + &author.tridge; + &author.jelmer; + <author>&person.gd;<contrib>LDAP updates</contrib></author> +</chapterinfo> + +<title>Domain Membership</title> + +<para> +<indexterm><primary>domain member</primary></indexterm> +<indexterm><primary>machine trust account</primary></indexterm> +<indexterm><primary>domain security</primary></indexterm> +Domain membership is a subject of vital concern. Samba must be able to +participate as a member server in a Microsoft domain security context, and +Samba must be capable of providing domain machine member trust accounts; +otherwise it would not be able to offer a viable option for many users. +</para> + +<para> +<indexterm><primary>domain membership</primary></indexterm> +<indexterm><primary>misinformation</primary></indexterm> +This chapter covers background information pertaining to domain membership, +the Samba configuration for it, and MS Windows client procedures for joining a +domain. Why is this necessary? Because both are areas in which there exists +within the current MS Windows networking world, and particularly in the +UNIX/Linux networking and administration world, a considerable level of +misinformation, incorrect understanding, and lack of knowledge. Hopefully +this chapter will fill the voids. +</para> + +<sect1> +<title>Features and Benefits</title> + +<para> +<indexterm><primary>domain security</primary></indexterm> +<indexterm><primary>single sign-on</primary></indexterm> +<indexterm><primary>SSO</primary></indexterm> +MS Windows workstations and servers that want to participate in domain security need to +be made domain members. Participating in domain security is often called +<emphasis>single sign-on</emphasis>, or <acronym>SSO</acronym> for short. This +chapter describes the process that must be followed to make a workstation +(or another server &smbmdash; be it an <application>MS Windows NT4/200x</application> +server) or a Samba server a member of an MS Windows domain security context. +</para> + +<para> +<indexterm><primary>native member</primary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +<indexterm><primary>domain control</primary></indexterm> +<indexterm><primary>Server Type</primary><secondary>Domain Member</secondary></indexterm> +Samba-3 can join an MS Windows NT4-style domain as a native member server, an +MS Windows Active Directory domain as a native member server, or a Samba domain +control network. Domain membership has many advantages: +</para> + +<itemizedlist> + <listitem><para> + <indexterm><primary>SAM</primary></indexterm> + MS Windows workstation users get the benefit of SSO. + </para></listitem> + + <listitem><para> + <indexterm><primary>access rights</primary></indexterm> + <indexterm><primary>file ownership</primary></indexterm> + <indexterm><primary>access controls</primary></indexterm> + <indexterm><primary>SAM</primary></indexterm> + Domain user access rights and file ownership/access controls can be set + from the single Domain Security Account Manager (SAM) database + (works with domain member servers as well as with MS Windows workstations + that are domain members). + </para></listitem> + + <listitem><para> + <indexterm><primary>domain members</primary></indexterm> + <indexterm><primary>network logon</primary></indexterm> + Only <application>MS Windows NT4/200x/XP Professional</application> + workstations that are domain members can use network logon facilities. + </para></listitem> + + <listitem><para> + <indexterm><primary>domain member</primary></indexterm> + <indexterm><primary>policy files</primary></indexterm> + <indexterm><primary>NTConfig.POL</primary></indexterm> + <indexterm><primary>desktop profiles</primary></indexterm> + Domain member workstations can be better controlled through the use of + policy files (<filename>NTConfig.POL</filename>) and desktop profiles. + </para></listitem> + + <listitem><para> + <indexterm><primary>logon script</primary></indexterm> + <indexterm><primary>transparent access</primary></indexterm> + <indexterm><primary>application servers</primary></indexterm> + Through the use of logon scripts, users can be given transparent access to network + applications that run off application servers. + </para></listitem> + + <listitem><para> + <indexterm><primary>user access management</primary></indexterm> + <indexterm><primary>SAM</primary></indexterm> + <indexterm><primary>LDAP</primary></indexterm> + <indexterm><primary>ADS</primary></indexterm> + Network administrators gain better application and user access management + abilities because there is no need to maintain user accounts on any network + client or server other than the central domain database + (either NT4/Samba SAM-style domain, NT4 domain that is backend-ed with an + LDAP directory, or via an Active Directory infrastructure). + </para></listitem> +</itemizedlist> + +</sect1> + +<sect1 id="machine-trust-accounts"> +<title>MS Windows Workstation/Server Machine Trust Accounts</title> + +<para> +<indexterm><primary>Machine Trust Accounts</primary></indexterm> +<indexterm><primary>authenticate</primary></indexterm> +<indexterm><primary>domain controller</primary></indexterm> +<indexterm><primary>rogue user</primary></indexterm> +A Machine Trust Account is an account that is used to authenticate a client machine (rather than a user) to +the domain controller server. In Windows terminology, this is known as a <quote>computer account.</quote> The +purpose of the machine trust account is to prevent a rogue user and domain controller from colluding to gain +access to a domain member workstation. +</para> + +<para> +<indexterm><primary>machine trust account</primary><secondary>password</secondary></indexterm> +<indexterm><primary>shared secret</primary></indexterm> +<indexterm><primary>unauthorized</primary></indexterm> +<indexterm><primary>Windows NT/200x/XP Professional</primary></indexterm> +<indexterm><primary>Windows 9x/Me/XP Home</primary></indexterm> +The password of a Machine Trust Account acts as the shared secret for secure communication with the domain +controller. This is a security feature to prevent an unauthorized machine with the same NetBIOS name from +joining the domain, participating in domain security operations, and gaining access to domain user/group +accounts. Windows NT/200x/XP Professional clients use machine trust accounts, but Windows 9x/Me/XP Home +clients do not. Hence, a Windows 9x/Me/XP Home client is never a true member of a domain because it does not +possess a Machine Trust Account, and, thus, has no shared secret with the domain controller. +</para> + +<para> +<indexterm><primary>Windows Registry</primary></indexterm> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +<indexterm><primary>Machine Trust Account</primary></indexterm> +A Windows NT4 PDC stores each Machine Trust Account in the Windows Registry. +The introduction of MS Windows 2000 saw the introduction of Active Directory, +the new repository for Machine Trust Accounts. A Samba PDC, however, stores +each Machine Trust Account in two parts, +as follows: + +<itemizedlist> + <listitem><para> + <indexterm><primary>domain security account</primary></indexterm> + <indexterm><primary>account information</primary></indexterm> + <indexterm><primary>backend database</primary></indexterm> + A domain security account (stored in the <smbconfoption name="passdb backend"/>) that has been configured in + the &smb.conf; file. The precise nature of the account information that is stored depends on the type of + backend database that has been chosen. + </para> + + <para> + <indexterm><primary>smbpasswd</primary></indexterm> + <indexterm><primary>UNIX login ID</primary></indexterm> + <indexterm><primary>UID</primary></indexterm> + <indexterm><primary>LanMan</primary></indexterm> + <indexterm><primary>NT-encrypted password</primary></indexterm> + <indexterm><primary>UNIX user identifier</primary><see>UID</see></indexterm> + The older format of this data is the <filename>smbpasswd</filename> database + that contains the UNIX login ID, the UNIX user identifier (UID), and the + LanMan and NT-encrypted passwords. There is also some other information in + this file that we do not need to concern ourselves with here. + </para> + + <para> + <indexterm><primary>database</primary></indexterm> + <indexterm><primary>ldapsam</primary></indexterm> + <indexterm><primary>smbpasswd</primary></indexterm> + <indexterm><primary>account controls</primary></indexterm> + The two newer database types are called ldapsam and tdbsam. Both store considerably more data than the older + <filename>smbpasswd</filename> file did. The extra information enables new user account controls to be + implemented. + </para></listitem> + + <listitem><para> + <indexterm><primary>UNIX account</primary></indexterm> + <indexterm><primary>/etc/passwd</primary></indexterm> + A corresponding UNIX account, typically stored in <filename>/etc/passwd</filename>. Work is in progress to + allow a simplified mode of operation that does not require UNIX user accounts, but this has not been a feature + of the early releases of Samba-3, and is not currently planned for release either. + </para></listitem> +</itemizedlist> +</para> + +<?latex \newpage ?> +<para> +<indexterm><primary>Machine Trust Accounts</primary><secondary>creating</secondary></indexterm> +There are three ways to create Machine Trust Accounts: +</para> + +<itemizedlist> + <listitem><para> + <indexterm><primary>manual UNIX account creation</primary></indexterm> + Manual creation from the UNIX/Linux command line. Here, both the Samba and + corresponding UNIX account are created by hand. + </para></listitem> + + <listitem><para> + <indexterm><primary>Server Manager</primary></indexterm> + <indexterm><primary>Nexus toolkit</primary></indexterm> + Using the MS Windows NT4 Server Manager, either from an NT4 domain member + server or using the Nexus toolkit available from the Microsoft Web site. + This tool can be run from any MS Windows machine as long as the user is + logged on as the administrator account. + </para></listitem> + + <listitem><para> + <indexterm><primary>Machine Trust Account</primary></indexterm> + <indexterm><primary>joined client</primary></indexterm> + <quote>On-the-fly</quote> creation. The Samba Machine Trust Account is automatically + created by Samba at the time the client is joined to the domain. + (For security, this is the recommended method.) The corresponding UNIX + account may be created automatically or manually. + </para></listitem> +</itemizedlist> + +<para> +<indexterm><primary>enforcing</primary></indexterm> +<indexterm><primary>machine trust account</primary><secondary>creation</secondary></indexterm> +Neither MS Windows NT4/200x/XP Professional, nor Samba, provide any method for enforcing the method of machine +trust account creation. This is a matter of the administrator's choice. +</para> + +<sect2> +<title>Manual Creation of Machine Trust Accounts</title> + +<para> +<indexterm><primary>/etc/passwd</primary></indexterm> +<indexterm><primary></primary></indexterm> +<indexterm><primary>useradd</primary></indexterm> +<indexterm><primary>vipw</primary></indexterm> +The first step in manually creating a Machine Trust Account is to manually +create the corresponding UNIX account in <filename>/etc/passwd</filename>. +This can be done using <command>vipw</command> or another <quote>adduser</quote> command +that is normally used to create new UNIX accounts. The following is an example for +a Linux-based Samba server: +<screen> +&rootprompt;<userinput>/usr/sbin/useradd -g machines -d /var/lib/nobody \ + -c <replaceable>"machine nickname"</replaceable> \ + -s /bin/false <replaceable>machine_name</replaceable>$ </userinput> + +&rootprompt;<userinput>passwd -l <replaceable>machine_name</replaceable>$</userinput> +</screen> +</para> + +<para> +<indexterm><primary>primary group</primary></indexterm> +<indexterm><primary>GID</primary></indexterm> +<indexterm><primary>machine accounts</primary></indexterm> +In the example above there is an existing system group <quote>machines</quote> which is used +as the primary group for all machine accounts. In the following examples the <quote>machines</quote> group +numeric GID is 100. +</para> + +<para> +<indexterm><primary>chpass</primary></indexterm> +<indexterm><primary>BSD</primary></indexterm> +On *BSD systems, this can be done using the <command>chpass</command> utility: +<screen> +&rootprompt;<userinput>chpass -a \ +'<replaceable>machine_name</replaceable>$:*:101:100::0:0:Windows <replaceable>machine_name</replaceable>:/dev/null:/sbin/nologin'</userinput> +</screen> +</para> + +<para> +<indexterm><primary>/etc/passwd</primary></indexterm> +<indexterm><primary>$</primary></indexterm> +<indexterm><primary>null shell</primary></indexterm> +<indexterm><primary>home directory</primary></indexterm> +The <filename>/etc/passwd</filename> entry will list the machine name +with a <quote>$</quote> appended, and will not have a password, will have a null shell and no +home directory. For example, a machine named <quote>doppy</quote> would have an +<filename>/etc/passwd</filename> entry like this: +<programlisting> +doppy$:x:505:100:<replaceable>machine_nickname</replaceable>:/dev/null:/bin/false +</programlisting> +</para> + +<para> +<indexterm><primary>machine_nickname</primary></indexterm> +<indexterm><primary>machine_name</primary></indexterm> +<indexterm><primary>Machine Trust Account</primary></indexterm> +in which <replaceable>machine_nickname</replaceable> can be any +descriptive name for the client, such as BasementComputer. +<replaceable>machine_name</replaceable> absolutely must be the NetBIOS +name of the client to be joined to the domain. The <quote>$</quote> must be +appended to the NetBIOS name of the client or Samba will not recognize +this as a Machine Trust Account. +</para> + +<para> +<indexterm><primary>UNIX account</primary></indexterm> +<indexterm><primary>Samba account</primary></indexterm> +<indexterm><primary>Machine Trust Account</primary><secondary>password</secondary></indexterm> +Now that the corresponding UNIX account has been created, the next step is to create +the Samba account for the client containing the well-known initial +Machine Trust Account password. This can be done using the +<command>smbpasswd</command> command +as shown here: +<screen> +&rootprompt;<userinput>smbpasswd -a -m <replaceable>machine_name</replaceable></userinput> +</screen> +</para> + +<para> +<indexterm><primary>machine_name</primary></indexterm> +<indexterm><primary>NetBIOS name</primary></indexterm> +<indexterm><primary>RID</primary></indexterm> +<indexterm><primary>UID</primary></indexterm> +where <replaceable>machine_name</replaceable> is the machine's NetBIOS +name. The RID of the new machine account is generated from the UID of +the corresponding UNIX account. +</para> + +<warning> +<title>Join the client to the domain immediately</title> + +<para> +<indexterm><primary>Machine Trust Account</primary></indexterm> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>Server Manager</primary></indexterm> +<indexterm><primary>changes password</primary></indexterm> +<indexterm><primary>NetBIOS name</primary></indexterm> +Manually creating a Machine Trust Account using this method is the +equivalent of creating a Machine Trust Account on a Windows NT PDC using +<indexterm><primary>Server Manager</primary></indexterm> +the <application>Server Manager</application>. From the time at which the +account is created to the time the client joins the domain and +changes the password, your domain is vulnerable to an intruder joining +your domain using a machine with the same NetBIOS name. A PDC inherently +trusts members of the domain and will serve out a large degree of user +information to such clients. You have been warned! +</para> +</warning> +</sect2> + +<sect2> +<title>Managing Domain Machine Accounts using NT4 Server Manager</title> + +<para> +<indexterm><primary>machine trust accounts</primary></indexterm> +<indexterm><primary>automatic account creation</primary></indexterm> +<indexterm><primary>Server Manager</primary></indexterm> +A working <smbconfoption name="add machine script"/> is essential +for machine trust accounts to be automatically created. This applies no matter whether +you use automatic account creation or the NT4 Domain Server Manager. +</para> + +<para> +<indexterm><primary>SRVTOOLS.EXE</primary></indexterm> +<indexterm><primary>SrvMgr.exe</primary></indexterm> +<indexterm><primary>UsrMgr.exe</primary></indexterm> +<indexterm><primary>domain management tools</primary></indexterm> +If the machine from which you are trying to manage the domain is an +<application>MS Windows NT4 workstation or MS Windows 200x/XP Professional</application>, +the tool of choice is the package called <command>SRVTOOLS.EXE</command>. +When executed in the target directory it will unpack <command>SrvMgr.exe</command> +and <command>UsrMgr.exe</command> (both are domain management tools for MS Windows NT4 workstation). +</para> + +<para> +<indexterm><primary>Nexus.exe</primary></indexterm> +<indexterm><primary>Microsoft Windows 9x/Me</primary></indexterm> +If your workstation is a <application>Microsoft Windows 9x/Me</application> family product, + you should download the <command>Nexus.exe</command> package from the Microsoft Web site. +When executed from the target directory, it will unpack the same tools but for use on +this platform. +</para> + +<para> +Further information about these tools may be obtained from Knowledge Base articles +<ulink url="http://support.microsoft.com/default.aspx?scid=kb;en-us;173673">173673</ulink>, and +<ulink url="http://support.microsoft.com/default.aspx?scid=kb;en-us;172540">172540</ulink> +</para> + +<para> +<indexterm><primary>srvmgr.exe</primary></indexterm> +<indexterm><primary>Server Manager for Domains</primary></indexterm> +Launch the <command>srvmgr.exe</command> (Server Manager for Domains) and follow these steps: +</para> + +<procedure> +<title>Server Manager Account Machine Account Management</title> + <step><para> + From the menu select <guimenu>Computer</guimenu>. + </para></step> + + <step><para> + Click <guimenuitem>Select Domain</guimenuitem>. + </para></step> + + <step><para> + Click the name of the domain you wish to administer in the + <guilabel>Select Domain</guilabel> panel and then click + <guibutton>OK</guibutton>. + </para></step> + + <step><para> + Again from the menu select <guimenu>Computer</guimenu>. + </para></step> + + <step><para> + Select <guimenuitem>Add to Domain</guimenuitem>. + </para></step> + + <step><para> + In the dialog box, click the radio button to + <guilabel>Add NT Workstation of Server</guilabel>, then + enter the machine name in the field provided, and click the + <guibutton>Add</guibutton> button. + </para></step> +</procedure> + +</sect2> + +<sect2> +<title>On-the-Fly Creation of Machine Trust Accounts</title> + +<para> +<indexterm><primary>Machine Trust Account</primary><secondary>creation</secondary></indexterm> +The third (and recommended) way of creating Machine Trust Accounts is simply to allow the Samba server to +create them as needed when the client is joined to the domain. +</para> + +<para> +<indexterm><primary>Machine Trust Account</primary><secondary>UNIX account</secondary></indexterm> +<indexterm><primary>UNIX account</primary></indexterm> +<indexterm><primary>add machine script</primary></indexterm> +Since each Samba Machine Trust Account requires a corresponding UNIX account, a method +for automatically creating the UNIX account is usually supplied; this requires configuration of the +add machine script option in &smb.conf;. This method is not required; however, corresponding UNIX +accounts may also be created manually. +</para> + + +<para> +<indexterm><primary>useradd</primary></indexterm> +<indexterm><primary>Red Hat Linux</primary></indexterm> +Here is an example for a Red Hat Linux system: +<smbconfblock> +<smbconfsection name="[global]"/> +<smbconfoption name="add machine script">/usr/sbin/useradd -d /var/lib/nobody -g 100 -s /bin/false -M %u</smbconfoption> +</smbconfblock> +</para> + +</sect2> + +<sect2><title>Making an MS Windows Workstation or Server a Domain Member</title> + +<para> +The procedure for making an MS Windows workstation or server a member of the domain varies +with the version of Windows. +</para> + +<sect3> + <title>Windows 200x/XP Professional Client</title> + + <para> +<indexterm><primary>domain member</primary></indexterm> +<indexterm><primary>machine trust account</primary><secondary>create privilege</secondary></indexterm> +<indexterm><primary>privileges</primary></indexterm> +<indexterm><primary>root</primary></indexterm> + When the user elects to make the client a domain member, Windows 200x prompts for + an account and password that has privileges to create machine accounts in the domain. + A Samba administrator account (i.e., a Samba account that has <constant>root</constant> privileges on the + Samba server) must be entered here; the operation will fail if an ordinary user + account is given. + </para> + + <para> +<indexterm><primary>administrator account</primary></indexterm> +<indexterm><primary>/etc/passwd</primary></indexterm> + For security reasons, the password for this administrator account should be set + to a password that is other than that used for the root user in <filename>/etc/passwd</filename>. + </para> + + <para> +<indexterm><primary>account</primary></indexterm> +<indexterm><primary>create domain member</primary></indexterm> +<indexterm><primary>root</primary></indexterm> +<indexterm><primary>map</primary></indexterm> + The name of the account that is used to create domain member machine trust accounts can be + anything the network administrator may choose. If it is other than <constant>root</constant>, + then this is easily mapped to <constant>root</constant> in the file named in the &smb.conf; parameter + <smbconfoption name="username map">/etc/samba/smbusers</smbconfoption>. + </para> + + <para> +<indexterm><primary>administrator account</primary></indexterm> +<indexterm><primary>encryption key</primary></indexterm> +<indexterm><primary>machine trust account</primary></indexterm> + The session key of the Samba administrator account acts as an encryption key for setting the password of the machine trust + account. The Machine Trust Account will be created on-the-fly, or updated if it already exists. + </para> +</sect3> + +<sect3> + <title>Windows NT4 Client</title> + + <para> +<indexterm><primary>Machine Trust Account</primary></indexterm> +<indexterm><primary>Create a Computer Account</primary></indexterm> +<indexterm><primary>join the machine</primary></indexterm> + If the Machine Trust Account was created manually, on the + Identification Changes menu enter the domain name, but do not + check the box <guilabel>Create a Computer Account in the Domain</guilabel>. + In this case, the existing Machine Trust Account is used to join the machine + to the domain. + </para> + + <para> +<indexterm><primary>Machine Trust Account</primary></indexterm> +<indexterm><primary>on the fly</primary></indexterm> +<indexterm><primary>Computer Account</primary></indexterm> +<indexterm><primary>administrator account</primary></indexterm> + If the Machine Trust Account is to be created on the fly, on the Identification Changes menu enter the domain + name and check the box <guilabel>Create a Computer Account in the Domain</guilabel>. In this case, joining + the domain proceeds as above for Windows 2000 (i.e., you must supply a Samba administrator account when + prompted). + </para> +</sect3> + +<sect3> + <title>Samba Client</title> + + <para> +<indexterm><primary></primary></indexterm> + Joining a Samba client to a domain is documented in <link linkend="domain-member-server">the next section</link>. + </para> +</sect3> + +</sect2> +</sect1> + +<sect1 id="domain-member-server"> +<title>Domain Member Server</title> + +<para> +<indexterm><primary>domain security</primary></indexterm> +<indexterm><primary>security context</primary></indexterm> +<indexterm><primary>authentication regime</primary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +This mode of server operation involves the Samba machine being made a member +of a domain security context. This means by definition that all user +authentication will be done from a centrally defined authentication regime. +The authentication regime may come from an NT3/4-style (old domain technology) +server, or it may be provided from an Active Directory server (ADS) running on +MS Windows 2000 or later. +</para> + +<para> +<emphasis> +<indexterm><primary>authentication</primary><secondary>backend</secondary></indexterm> +<indexterm><primary>distributed directory</primary></indexterm> +<indexterm><primary>LDAP</primary></indexterm> +<indexterm><primary>OpenLDAP</primary></indexterm> +<indexterm><primary>iPlanet</primary></indexterm> +<indexterm><primary>Sun</primary></indexterm> +<indexterm><primary>Novell</primary></indexterm> +<indexterm><primary>e-Directory</primary></indexterm> +Of course it should be clear that the authentication backend itself could be +from any distributed directory architecture server that is supported by Samba. +This can be LDAP (from OpenLDAP), or Sun's iPlanet, or Novell e-Directory +Server, and so on. +</emphasis> +</para> + +<note><para> +<indexterm><primary>LDAP</primary></indexterm> +<indexterm><primary>identity management</primary></indexterm> +<indexterm><primary>machine authentication</primary></indexterm> +When Samba is configured to use an LDAP or other identity management and/or +directory service, it is Samba that continues to perform user and machine +authentication. It should be noted that the LDAP server does not perform +authentication handling in place of what Samba is designed to do. +</para></note> + +<para> +<indexterm><primary>create a domain machine account</primary></indexterm> +<indexterm><primary>domain member server</primary></indexterm> +<indexterm><primary>join the domain</primary></indexterm> +Please refer to <link linkend="samba-pdc">Domain Control</link>, for more information regarding +how to create a domain machine account for a domain member server as well as for +information on how to enable the Samba domain member machine to join the domain +and be fully trusted by it. +</para> + +<sect2> +<title>Joining an NT4-type Domain with Samba-3</title> + +<para><link linkend="assumptions">Assumptions</link> lists names that are used in the remainder of this chapter.</para> + +<table frame="all" id="assumptions"><title>Assumptions</title> + <tgroup cols="2"> + <colspec align="right"/> + <colspec align="left"/> + <tbody> + <row> + <entry>Samba DMS NetBIOS name:</entry><entry>SERV1</entry> + </row> + <row> + <entry>Windows 200x/NT domain name:</entry><entry>&example.workgroup;</entry> + </row> + <row> + <entry>Domain's PDC NetBIOS name:</entry><entry>DOMPDC</entry> + </row> + <row> + <entry>Domain's BDC NetBIOS names:</entry><entry>DOMBDC1 and DOMBDC2</entry> + </row> + </tbody> + </tgroup> +</table> + +<para> +<indexterm><primary></primary></indexterm> +First, you must edit your &smb.conf; file to tell Samba it should now use domain security. +</para> + +<para> +<indexterm><primary>security = user</primary></indexterm> +<indexterm><primary>standalone server</primary></indexterm> +<indexterm><primary>domain member server</primary></indexterm> +<indexterm><primary>domain security</primary></indexterm> +Change (or add) your <smbconfoption name="security"/> line in the [global] section +of your &smb.conf; to read: +<smbconfblock> +<smbconfoption name="security">domain</smbconfoption> +</smbconfblock> +Note that if the parameter <parameter>security = user</parameter> is used, this machine would function as a +standalone server and not as a domain member server. Domain security mode causes Samba to work within the +domain security context. +</para> + +<para> +Next change the <smbconfoption name="workgroup"/> line in the <smbconfsection name="[global]"/> +section to read: +<smbconfblock> +<smbconfoption name="workgroup">&example.workgroup;</smbconfoption> +</smbconfblock> +This is the name of the domain we are joining. +</para> + +<para> +<indexterm><primary>authenticate</primary></indexterm> +<indexterm><primary>PDC</primary></indexterm> +You must also have the parameter <smbconfoption name="encrypt passwords"/> +set to <constant>yes</constant> in order for your users to authenticate to the NT PDC. +This is the default setting if this parameter is not specified. There is no need to specify this +parameter, but if it is specified in the &smb.conf; file, it must be set to <constant>Yes</constant>. +</para> + +<para> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>BDC</primary></indexterm> +<indexterm><primary>authenticate users</primary></indexterm> +<indexterm><primary>domain controllers</primary></indexterm> +Finally, add (or modify) a <smbconfoption name="password server"/> line in the [global] +section to read: +<smbconfblock> +<smbconfoption name="password server">DOMPDC DOMBDC1 DOMBDC2</smbconfoption> +</smbconfblock> +These are the PDC and BDCs Samba +will attempt to contact in order to authenticate users. Samba will +try to contact each of these servers in order, so you may want to +rearrange this list in order to spread out the authentication load +among Domain Controllers. +</para> + +<para> +<indexterm><primary>list of domain controllers</primary></indexterm> +<indexterm><primary>mechanism</primary></indexterm> +<indexterm><primary>broadcast-based name resolution</primary></indexterm> +<indexterm><primary>DNS name resolution</primary></indexterm> +Alternatively, if you want smbd to determine automatically the list of domain controllers to use for +authentication, you may set this line to be: +<smbconfblock> +<smbconfoption name="password server">*</smbconfoption> +</smbconfblock> +<indexterm><primary>WINS</primary></indexterm> +This method allows Samba to use exactly the same mechanism that NT does. The +method either uses broadcast-based name resolution, performs a WINS database +lookup in order to find a domain controller against which to authenticate, +or locates the domain controller using DNS name resolution. +</para> + +<para> +To join the domain, run this command: +<indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm> +<screen> +&rootprompt;<userinput>net rpc join -S DOMPDC -U<replaceable>Administrator%password</replaceable></userinput> +</screen> +</para> + +<para> +<indexterm><primary>NetBIOS name</primary></indexterm> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>WINS lookup</primary></indexterm> +<indexterm><primary>NetBIOS broadcast</primary></indexterm> +If the <option>-S DOMPDC</option> argument is not given, the domain name will be obtained from &smb.conf; and +the NetBIOS name of the PDC will be obtained either using a WINS lookup or via NetBIOS broadcast based name +look up. +</para> + +<para> +<indexterm><primary>joining the domain</primary></indexterm> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>Administrator%password</primary></indexterm> +<indexterm><primary>Joined domain</primary></indexterm> +The machine is joining the domain DOM, and the PDC for that domain (the only machine +that has write access to the domain SAM database) is DOMPDC; therefore, use the <option>-S</option> +option. The <replaceable>Administrator%password</replaceable> is the login name and +password for an account that has the necessary privilege to add machines to the +domain. If this is successful, you will see the following message in your terminal window. +Where the older NT4-style domain architecture is used: +<screen> +<computeroutput>Joined domain DOM.</computeroutput> +</screen> +</para> + +<para> +<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>join</tertiary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +<indexterm><primary>join the ADS domain</primary></indexterm> +Where Active Directory is used, the command used to join the ADS domain is: +<screen> +&rootprompt; net ads join -U<replaceable>Administrator%password</replaceable> +</screen> +And the following output is indicative of a successful outcome: +<screen> +<computeroutput>Joined SERV1 to realm MYREALM.</computeroutput> +</screen> +</para> + +<para> +Refer to the <command>net</command> man page and to <link linkend="NetCommand">the chapter on remote +administration</link> for further information. +</para> + +<para> +<indexterm><primary>join the domain</primary></indexterm> +<indexterm><primary>create machine trust account</primary></indexterm> +<indexterm><primary>PDC</primary></indexterm> +This process joins the server to the domain without separately having to create the machine +trust account on the PDC beforehand. +</para> + +<para> +<indexterm><primary>machine account password</primary><secondary>change protocol</secondary></indexterm> +<indexterm><primary>random machine account password</primary></indexterm> +<indexterm><primary>/usr/local/samba/private/secrets.tdb</primary></indexterm> +<indexterm><primary>/etc/samba/secrets.tdb</primary></indexterm> +This command goes through the machine account password change protocol, then writes the new (random) machine +account password for this Samba server into a file in the same directory in which a smbpasswd file would be +normally stored. The trust account information that is needed by the DMS is written into the file +<filename>/usr/local/samba/private/secrets.tdb</filename> or <filename>/etc/samba/secrets.tdb</filename>. +</para> + +<para> +<indexterm><primary>domain-level security</primary></indexterm> +<indexterm><primary>shadow password file</primary></indexterm> +This file is created and owned by root and is not readable by any other user. It is +the key to the domain-level security for your system and should be treated as carefully +as a shadow password file. +</para> + +<para> +<indexterm><primary>Samba daemons</primary></indexterm> +<indexterm><primary>distribution</primary></indexterm> +<indexterm><primary>/etc/init.d/samba</primary></indexterm> +Finally, restart your Samba daemons and get ready for clients to begin using domain +security. The way you can restart your Samba daemons depends on your distribution, +but in most cases the following will suffice: +<screen> +&rootprompt;/etc/init.d/samba restart +</screen> +</para> + +</sect2> + +<sect2> +<title>Why Is This Better Than <parameter>security = server</parameter>?</title> + +<para> +<indexterm><primary>domain security</primary></indexterm> +<indexterm><primary>UNIX users</primary></indexterm> +<indexterm><primary>authentication</primary></indexterm> +Currently, domain security in Samba does not free you from having to create local UNIX users to represent the +users attaching to your server. This means that if domain user <constant>DOM\fred</constant> attaches to your +domain security Samba server, there needs to be a local UNIX user fred to represent that user in the UNIX file +system. This is similar to the older Samba security mode <smbconfoption +name="security">server</smbconfoption>, where Samba would pass through the authentication request to a Windows +NT server in the same way as a Windows 95 or Windows 98 server would. +</para> + +<para> +<indexterm><primary>winbind</primary></indexterm> +<indexterm><primary>UID</primary></indexterm> +<indexterm><primary>GID</primary></indexterm> +Please refer to <link linkend="winbind">Winbind: Use of Domain Accounts</link>, for information on a system +to automatically assign UNIX UIDs and GIDs to Windows NT domain users and groups. +</para> + +<para> +<indexterm><primary>domain-level</primary></indexterm> +<indexterm><primary>authentication</primary></indexterm> +<indexterm><primary>RPC</primary></indexterm> +The advantage of domain-level security is that the authentication in domain-level security is passed down the +authenticated RPC channel in exactly the same way that an NT server would do it. This means Samba servers now +participate in domain trust relationships in exactly the same way NT servers do (i.e., you can add Samba +servers into a resource domain and have the authentication passed on from a resource domain PDC to an account +domain PDC). +</para> + +<para> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>BDC</primary></indexterm> +<indexterm><primary>connection resources</primary></indexterm> +In addition, with <smbconfoption name="security">server</smbconfoption>, every Samba daemon on a server has to +keep a connection open to the authenticating server for as long as that daemon lasts. This can drain the +connection resources on a Microsoft NT server and cause it to run out of available connections. With +<smbconfoption name="security">domain</smbconfoption>, however, the Samba daemons connect to the PDC or BDC +only for as long as is necessary to authenticate the user and then drop the connection, thus conserving PDC +connection resources. +</para> + +<para> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>authentication reply</primary></indexterm> +<indexterm><primary>SID</primary></indexterm> +<indexterm><primary>NT groups</primary></indexterm> +Finally, acting in the same manner as an NT server authenticating to a PDC means that as part of the +authentication reply, the Samba server gets the user identification information such as the user SID, the list +of NT groups the user belongs to, and so on. +</para> + +<note> +<para> +Much of the text of this document was first published in the Web magazine +<ulink url="http://www.linuxworld.com"><emphasis>LinuxWorld</emphasis></ulink> as the article <ulink +url="http://www.linuxworld.com/linuxworld/lw-1998-10/lw-10-samba.html"/> +<emphasis>Doing the NIS/NT Samba</emphasis>. +</para> +</note> + +</sect2> +</sect1> + +<sect1 id="ads-member"> +<title>Samba ADS Domain Membership</title> + +<para> +<indexterm significance="preferred"><primary>Active Directory</primary></indexterm> +<indexterm significance="preferred"><primary>ADS</primary><see>Active Directory</see></indexterm> +<indexterm><primary>KDC</primary></indexterm> +<indexterm><primary>Kerberos</primary></indexterm> +This is a rough guide to setting up Samba-3 with Kerberos authentication against a +Windows 200x KDC. A familiarity with Kerberos is assumed. +</para> + +<sect2> +<title>Configure &smb.conf;</title> + +<para> +You must use at least the following three options in &smb.conf;: +</para> + +<smbconfblock> +<smbconfoption name="realm">your.kerberos.REALM</smbconfoption> +<smbconfoption name="security">ADS</smbconfoption> +<smbconfcomment>The following parameter need only be specified if present.</smbconfcomment> +<smbconfcomment>The default setting if not present is Yes.</smbconfcomment> +<smbconfoption name="encrypt passwords">yes</smbconfoption> +</smbconfblock> + +<para> +<indexterm><primary>ADS</primary></indexterm> +<indexterm><primary>realm</primary></indexterm> +<indexterm><primary>DNS</primary></indexterm> +<indexterm><primary>ADS DC</primary></indexterm> +<indexterm><primary>password server</primary></indexterm> +In case samba cannot correctly identify the appropriate ADS server using the realm name, use the +<smbconfoption name="password server"/> option in &smb.conf;: +<smbconfblock> +<smbconfoption name="password server">your.kerberos.server</smbconfoption> +</smbconfblock> +The most common reason for which Samba may not be able to locate the ADS domain controller is a consequence of +sites maintaining some DNS servers on UNIX systems without regard for the DNS requirements of the ADS +infrastructure. There is no harm in specifying a preferred ADS domain controller using the <parameter>password +server</parameter>. +</para> + +<note><para> +<indexterm><primary>smbpasswd</primary></indexterm> +<indexterm><primary>authenticated</primary></indexterm> +You do <emphasis>not</emphasis> need an smbpasswd file, and older clients will be authenticated as +if <smbconfoption name="security">domain</smbconfoption>, although it will not do any harm and +allows you to have local users not in the domain. +</para></note> + +</sect2> + +<sect2> +<title>Configure <filename>/etc/krb5.conf</filename></title> + +<para> +<indexterm><primary>/etc/krb5.conf</primary></indexterm> +<indexterm><primary>Kerberos</primary><secondary>/etc/krb5.conf</secondary></indexterm> +<indexterm><primary>MIT</primary></indexterm> +<indexterm><primary>Heimdal</primary></indexterm> +With both MIT and Heimdal Kerberos, it is unnecessary to configure the <filename>/etc/krb5.conf</filename>, +and it may be detrimental. +</para> + +<para> +<indexterm><primary>ADS</primary></indexterm> +<indexterm><primary>SRV records</primary></indexterm> +<indexterm><primary>DNS zon</primary></indexterm> +<indexterm><primary>KDC</primary></indexterm> +<indexterm><primary>_kerberos.REALM.NAME</primary></indexterm> +Microsoft ADS automatically create SRV records in the DNS zone +<parameter>_kerberos._tcp.REALM.NAME</parameter> for each KDC in the realm. This is part +of the installation and configuration process used to create an Active Directory domain. +A KDC is a Kerberos Key Distribution Center and forms an integral part of the Microsoft +active directory infrastructure. +</para> + +<para> +<indexterm><primary>kinit</primary></indexterm> +<indexterm><primary>DES-CBC-MD5</primary></indexterm> +<indexterm><primary>DES-CBC-CRC</primary></indexterm> +<indexterm><primary>encryption types</primary></indexterm> +<indexterm><primary>kerberos</primary></indexterm> +<indexterm><primary>Windows 2000</primary></indexterm> +UNIX systems can use kinit and the DES-CBC-MD5 or DES-CBC-CRC encryption types to authenticate to the Windows +2000 KDC. For further information regarding Windows 2000 ADS kerberos interoperability please refer to the +Microsoft Windows 2000 Kerberos <ulink +url="http://www.microsoft.com/windows2000/techinfo/planning/security/kerbsteps.asp">Interoperability</ulink> +guide. Another very useful document that may be referred to for general information regarding Kerberos +interoperability is <ulink url="http://www.ietf.org/rfc/rfc1510.txt?number=1510">RFC1510</ulink>. This RFC +explains much of the magic behind the operation of Kerberos. +</para> + +<para> +<indexterm><primary>MIT</primary></indexterm> +<indexterm><primary>KRB5</primary></indexterm> +<indexterm><primary>SRV records</primary></indexterm> +<indexterm><primary>krb5.conf</primary></indexterm> +<indexterm><primary>DNS lookup</primary></indexterm> +<indexterm><primary>libraries</primary></indexterm> +MIT's, as well as Heimdal's, recent KRB5 libraries default to checking for SRV records, so they will +automatically find the KDCs. In addition, <filename>krb5.conf</filename> only allows specifying +a single KDC, even there if there may be more than one. Using the DNS lookup allows the KRB5 +libraries to use whichever KDCs are available. +</para> + +<para> +<indexterm><primary>krb5.conf</primary></indexterm> +When manually configuring <filename>krb5.conf</filename>, the minimal configuration is: +<screen> +[libdefaults] + default_realm = YOUR.KERBEROS.REALM + +[realms] + YOUR.KERBEROS.REALM = { + kdc = your.kerberos.server + } + +[domain_realms] + .kerberos.server = YOUR.KERBEROS.REALM +</screen> +</para> + +<para> +<indexterm><primary>Heimdal</primary></indexterm> +When using Heimdal versions before 0.6, use the following configuration settings: +<screen> +[libdefaults] + default_realm = YOUR.KERBEROS.REALM + default_etypes = des-cbc-crc des-cbc-md5 + default_etypes_des = des-cbc-crc des-cbc-md5 + +[realms] + YOUR.KERBEROS.REALM = { + kdc = your.kerberos.server + } + +[domain_realms] + .kerberos.server = YOUR.KERBEROS.REALM +</screen> +</para> + +<para> +<indexterm><primary>KDC</primary></indexterm> +<indexterm><primary>kinit</primary></indexterm> +Test your config by doing a <userinput>kinit +<replaceable>USERNAME</replaceable>@<replaceable>REALM</replaceable></userinput> and +making sure that your password is accepted by the Win2000 KDC. +</para> + +<para> +<indexterm><primary>Heimdal</primary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +<indexterm><primary>KDC</primary></indexterm> +<indexterm><primary>Windows 2003</primary></indexterm> +With Heimdal versions earlier than 0.6.x you can use only newly created accounts +in ADS or accounts that have had the password changed once after migration, or +in case of <constant>Administrator</constant> after installation. At the +moment, a Windows 2003 KDC can only be used with Heimdal releases later than 0.6 +(and no default etypes in krb5.conf). Unfortunately, this whole area is still +in a state of flux. +</para> + +<note><para> +<indexterm><primary>realm</primary></indexterm> +<indexterm><primary>uppercase</primary></indexterm> +<indexterm><primary>KDC</primary></indexterm> +The realm must be in uppercase or you will get a <quote><errorname>Cannot find KDC for +requested realm while getting initial credentials</errorname></quote> error (Kerberos +is case-sensitive!). +</para></note> + +<note><para> +<indexterm><primary>synchronize</primary></indexterm> +<indexterm><primary>credentials</primary></indexterm> +<indexterm><primary>time difference</primary></indexterm> +<indexterm><primary>clock skew</primary></indexterm> +Time between the two servers must be synchronized. You will get a <quote><errorname>kinit(v5): Clock skew too +great while getting initial credentials</errorname></quote> if the time difference (clock skew) is more than five minutes. +</para></note> + +<para> +<indexterm><primary>clock skew</primary></indexterm> +<indexterm><primary>Kerberos</primary></indexterm> +Clock skew limits are configurable in the Kerberos protocols. The default setting is five minutes. +</para> + +<para> +<indexterm><primary>DNS</primary></indexterm> +<indexterm><primary>KDC</primary></indexterm> +<indexterm><primary>hostname</primary></indexterm> +<indexterm><primary>realm</primary></indexterm> +You also must ensure that you can do a reverse DNS lookup on the IP address of your KDC. Also, the name that +this reverse lookup maps to must either be the NetBIOS name of the KDC (i.e., the hostname with no domain +attached) or it can be the NetBIOS name followed by the realm. +</para> + +<para> +<indexterm><primary>/etc/hosts</primary></indexterm> +<indexterm><primary>KDC</primary></indexterm> +<indexterm><primary>realm</primary></indexterm> +The easiest way to ensure you get this right is to add a <filename>/etc/hosts</filename> entry mapping the IP +address of your KDC to its NetBIOS name. If you do not get this correct, then you will get a <errorname>local +error</errorname> when you try to join the realm. +</para> + +<para> +<indexterm><primary>Kerberos</primary></indexterm> +<indexterm><primary>Create the Computer Account</primary></indexterm> +<indexterm><primary>Testing Server Setup</primary></indexterm> +<indexterm><primary></primary></indexterm> +If all you want is Kerberos support in &smbclient;, then you can skip directly to <link +linkend="ads-test-smbclient">Testing with &smbclient;</link> now. <link +linkend="ads-create-machine-account">Create the Computer Account</link> and <link +linkend="ads-test-server">Testing Server Setup</link> are needed only if you want Kerberos support for &smbd; +and &winbindd;. +</para> + +</sect2> + +<sect2 id="ads-create-machine-account"> +<title>Create the Computer Account</title> + +<para> +<indexterm><primary>write permission</primary></indexterm> +<indexterm><primary>Samba private directory</primary></indexterm> +<indexterm><primary>Administrator account</primary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +As a user who has write permission on the Samba private directory (usually root), run: +<screen> +&rootprompt; <userinput>net ads join -U Administrator%password</userinput> +</screen> +The Administrator account can be any account that has been designated in the ADS domain security settings with +permission to add machines to the ADS domain. It is, of course, a good idea to use an account other than Administrator. +On the UNIX/Linux system, this command must be executed by an account that has UID=0 (root). +</para> + +<para> +<indexterm><primary>ADS</primary></indexterm> +<indexterm><primary>machine trust account</primary></indexterm> +<indexterm><primary>organizational unit</primary></indexterm> +<indexterm><primary>ADS manager</primary></indexterm> +<indexterm><primary>kinit</primary></indexterm> +<indexterm><primary>net</primary><secondary>ads</secondary><tertiary>join</tertiary></indexterm> +When making a Windows client a member of an ADS domain within a complex organization, you +may want to create the machine trust account within a particular organizational unit. Samba-3 permits +this to be done using the following syntax: +<screen> +&rootprompt; <userinput>kinit Administrator@your.kerberos.REALM</userinput> +&rootprompt; <userinput>net ads join createcomputer="organizational_unit"</userinput> +</screen> +Your ADS manager will be able to advise what should be specified for the "organizational_unit" parameter. +</para> + +<para> +<indexterm><primary>organizational directory</primary></indexterm> +<indexterm><primary>machine trust account</primary></indexterm> +<indexterm><primary>container</primary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +For example, you may want to create the machine trust account in a container called <quote>Servers</quote> +under the organizational directory <quote>Computers/BusinessUnit/Department,</quote> like this: +<screen> +&rootprompt; <userinput>net ads join "Computers/BusinessUnit/Department/Servers"</userinput> +</screen> +This command will place the Samba server machine trust account in the container +<literal>Computers/BusinessUnit/Department/Servers</literal>. The container should exist in the ADS directory +before executing this command. Please note that forward slashes must be used, because backslashes are both +valid characters in an OU name and used as escapes for other characters. If you need a backslash in an OU +name, it may need to be quadrupled to pass through the shell escape and ldap escape. +</para> + +<sect3> +<title>Possible Errors</title> + +<para> +<variablelist> + <varlistentry><term><errorname>ADS support not compiled in</errorname></term> + <listitem><para> + <indexterm><primary>config.cache</primary></indexterm> + <indexterm><primary>Kerberos</primary></indexterm> + <indexterm><primary>headers files</primary></indexterm> + Samba must be reconfigured (remove config.cache) and recompiled (make clean all install) after the + Kerberos libraries and headers files are installed. + </para></listitem></varlistentry> + + <varlistentry><term><errorname>net ads join prompts for user name</errorname></term> + <listitem><para> + <indexterm><primary>kinit</primary></indexterm> + <indexterm><primary>rights</primary></indexterm> + You need to log in to the domain using <userinput>kinit + <replaceable>USERNAME</replaceable>@<replaceable>REALM</replaceable></userinput>. + <replaceable>USERNAME</replaceable> must be a user who has rights to add a machine to the domain. + </para></listitem></varlistentry> + + <varlistentry><term>Unsupported encryption/or checksum types</term> + <listitem><para> + <indexterm><primary>/etc/krb5.conf</primary></indexterm> + <indexterm><primary>unsupported encryption</primary></indexterm> + <indexterm><primary>Kerberos</primary></indexterm> + Make sure that the <filename>/etc/krb5.conf</filename> is correctly configured + for the type and version of Kerberos installed on the system. + </para></listitem></varlistentry> +</variablelist> +</para> + +</sect3> + +</sect2> + +<sect2 id="ads-test-server"> +<title>Testing Server Setup</title> + +<para> +<indexterm><primary>successful join</primary></indexterm> +<indexterm><primary>computer account</primary></indexterm> +<indexterm><primary>ADS</primary></indexterm> +If the join was successful, you will see a new computer account with the +NetBIOS name of your Samba server in Active Directory (in the <quote>Computers</quote> +folder under Users and Computers. +</para> + +<para> +<indexterm><primary>Windows 2000</primary></indexterm> +<indexterm><primary>net</primary><secondary>use</secondary></indexterm> +<indexterm><primary>DES-CBC-MD5</primary></indexterm> +On a Windows 2000 client, try <userinput>net use * \\server\share</userinput>. You should +be logged in with Kerberos without needing to know a password. If this fails, then run +<userinput>klist tickets</userinput>. Did you get a ticket for the server? Does it have +an encryption type of DES-CBC-MD5? +</para> + +<note><para> +<indexterm><primary>DES-CBC-MD5</primary></indexterm> +<indexterm><primary>ARCFOUR-HMAC-MD5</primary></indexterm> +<indexterm><primary>encoding</primary></indexterm> +Samba can use both DES-CBC-MD5 encryption as well as ARCFOUR-HMAC-MD5 encoding. +</para></note> + +</sect2> + +<sect2 id="ads-test-smbclient"> +<title>Testing with &smbclient;</title> + +<para> +<indexterm><primary>smbclient</primary></indexterm> +<indexterm><primary>Kerberos</primary></indexterm> +<indexterm><primary>Kerberos authentication</primary></indexterm> +On your Samba server try to log in to a Windows 2000 server or your Samba +server using &smbclient; and Kerberos. Use &smbclient; as usual, but +specify the <option>-k</option> option to choose Kerberos authentication. +</para> + +</sect2> + +<sect2> +<title>Notes</title> + +<para> +<indexterm><primary>administrator password</primary></indexterm> +<indexterm><primary>change password</primary></indexterm> +<indexterm><primary>encryption types</primary></indexterm> +You must change the administrator password at least once after installing a domain controller, +to create the right encryption types. +</para> + +<para> +<indexterm><primary>_kerberos._udp</primary></indexterm> +<indexterm><primary>_ldap._tcp</primary></indexterm> +<indexterm><primary>default DNS setup</primary></indexterm> +Windows 200x does not seem to create the <parameter>_kerberos._udp</parameter> and +<parameter>_ldap._tcp</parameter> in the default DNS setup. Perhaps this will be fixed later in service packs. +</para> + +</sect2> +</sect1> + +<sect1> +<title>Sharing User ID Mappings between Samba Domain Members</title> + +<para> +<indexterm><primary>maps UNIX users and groups</primary></indexterm> +<indexterm><primary>UID</primary></indexterm> +<indexterm><primary>GID</primary></indexterm> +<indexterm><primary>SID</primary></indexterm> +Samba maps UNIX users and groups (identified by UIDs and GIDs) to Windows users and groups (identified by SIDs). +These mappings are done by the <parameter>idmap</parameter> subsystem of Samba. +</para> + +<para> +<indexterm><primary>mappings</primary></indexterm> +<indexterm><primary>CIFS</primary></indexterm> +<indexterm><primary>NFS</primary></indexterm> +In some cases it is useful to share these mappings between Samba domain members, +so <emphasis>name->id</emphasis> mapping is identical on all machines. +This may be needed in particular when sharing files over both CIFS and NFS. +</para> + +<para> +<indexterm><primary>LDAP</primary></indexterm> +<indexterm><primary>ldap idmap suffix</primary></indexterm> +To use the <emphasis>LDAP</emphasis> <parameter>ldap idmap suffix</parameter>, set: +</para> + +<smbconfblock> +<smbconfoption name="ldap idmap suffix">ou=Idmap</smbconfoption> +</smbconfblock> + +<para> +See the &smb.conf; man page entry for the <smbconfoption name="ldap idmap suffix"></smbconfoption> +parameter for further information. +</para> + +<para> +<indexterm><primary>smbpasswd</primary></indexterm> +<indexterm><primary>LDAP administrative password</primary></indexterm> +<indexterm><primary>secrets.tdb</primary></indexterm> +Do not forget to specify also the <smbconfoption name="ldap admin dn"/> +and to make certain to set the LDAP administrative password into the <filename>secrets.tdb</filename> using: +<screen> +&rootprompt; smbpasswd -w ldap-admin-password +</screen> +In place of <literal>ldap-admin-password</literal>, substitute the LDAP administration password for your +system. +</para> + +</sect1> + +<sect1> +<title>Common Errors</title> + +<para> +<indexterm><primary>domain member</primary></indexterm> +<indexterm><primary>machine trust accounts</primary></indexterm> +In the process of adding/deleting/re-adding domain member machine trust accounts, there are +many traps for the unwary player and many <quote>little</quote> things that can go wrong. +It is particularly interesting how often subscribers on the Samba mailing list have concluded +after repeated failed attempts to add a machine account that it is necessary to <quote>reinstall</quote> +MS Windows on the machine. In truth, it is seldom necessary to reinstall because of this type +of problem. The real solution is often quite simple, and with an understanding of how MS Windows +networking functions, it is easy to overcome. +</para> + +<sect2> +<title>Cannot Add Machine Back to Domain</title> + +<para> +<indexterm><primary>machine trust account</primary></indexterm> +<indexterm><primary>already exists</primary></indexterm> +<quote>A Windows workstation was reinstalled. The original domain machine trust +account was deleted and added immediately. The workstation will not join the domain if I use +the same machine name. Attempts to add the machine fail with a message that the machine already +exists on the network &smbmdash; I know it does not. Why is this failing?</quote> +</para> + +<para> +<indexterm><primary>NetBIOS name cache</primary></indexterm> +<indexterm><primary>nbtstat</primary></indexterm> +The original name is still in the NetBIOS name cache and must expire after machine account +deletion before adding that same name as a domain member again. The best advice is to delete +the old account and then add the machine with a new name. Alternately, the name cache can be flushed and +reloaded with current data using the <command>nbtstat</command> command on the Windows client: +<screen> +&dosprompt; nbtstat -R +</screen> +</para> + +</sect2> + +<sect2> +<title>Adding Machine to Domain Fails</title> + +<para> +<indexterm><primary>PDC</primary></indexterm> +<indexterm><primary>fails</primary></indexterm> +<quote>Adding a Windows 200x or XP Professional machine to the Samba PDC Domain fails with a +message that says, <errorname>"The machine could not be added at this time, there is a network problem. +Please try again later."</errorname> Why?</quote> +</para> + +<para> +<indexterm><primary>check logs</primary></indexterm> +You should check that there is an <smbconfoption name="add machine script"/> in your &smb.conf; +file. If there is not, please add one that is appropriate for your OS platform. If a script +has been defined, you will need to debug its operation. Increase the <smbconfoption name="log level"></smbconfoption> +in the &smb.conf; file to level 10, then try to rejoin the domain. Check the logs to see which +operation is failing. +</para> + +<para> +Possible causes include: +</para> + +<itemizedlist> + <listitem><para> +<indexterm><primary>script</primary></indexterm> +<indexterm><primary>path specified</primary></indexterm> + The script does not actually exist, or could not be located in the path specified. + </para> + + <para> +<indexterm><primary>UNIX system account</primary></indexterm> +<indexterm><primary>Samba SAM account</primary></indexterm> + <emphasis>Corrective action:</emphasis> Fix it. Make sure when run manually + that the script will add both the UNIX system account and the Samba SAM account. + </para></listitem> + + <listitem><para> +<indexterm><primary>UNIX system account</primary></indexterm> +<indexterm><primary>/etc/passwd</primary></indexterm> + The machine could not be added to the UNIX system accounts file <filename>/etc/passwd</filename>. + </para> + + <para> +<indexterm><primary>legal UNIX system account name</primary></indexterm> +<indexterm><primary>uppercase</primary></indexterm> + <emphasis>Corrective action:</emphasis> Check that the machine name is a legal UNIX + system account name. If the UNIX utility <command>useradd</command> is called, + then make sure that the machine name you are trying to add can be added using this + tool. <command>Useradd</command> on some systems will not allow any uppercase characters + nor will it allow spaces in the name. + </para></listitem> +</itemizedlist> + +<para> +<indexterm><primary>backend database</primary></indexterm> +<indexterm><primary>UNIX system account</primary></indexterm> +<indexterm><primary>Samba backend database</primary></indexterm> +The <smbconfoption name="add machine script"/> does not create the +machine account in the Samba backend database; it is there only to create a UNIX system +account to which the Samba backend database account can be mapped. +</para> + +</sect2> + +<sect2> + <title>I Can't Join a Windows 2003 PDC</title> + + <para> +<indexterm><primary>SMB signing</primary></indexterm> +<indexterm><primary>SMB</primary></indexterm> +<indexterm><primary>Windows 2003</primary></indexterm> +<indexterm><primary>SMB/CIFS</primary></indexterm> + Windows 2003 requires SMB signing. Client-side SMB signing has been implemented in Samba-3.0. + Set <smbconfoption name="client use spnego">yes</smbconfoption> when communicating + with a Windows 2003 server. This will not interfere with other Windows clients that do not + support the more advanced security features of Windows 2003 because the client will simply + negotiate a protocol that both it and the server suppport. This is a well-known fall-back facility + that is built into the SMB/CIFS protocols. + </para> + +</sect2> + +</sect1> +</chapter> |