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diff --git a/docs-xml/Samba3-ByExample/SBE-AddingUNIXClients.xml b/docs-xml/Samba3-ByExample/SBE-AddingUNIXClients.xml deleted file mode 100644 index f28f4a1085b..00000000000 --- a/docs-xml/Samba3-ByExample/SBE-AddingUNIXClients.xml +++ /dev/null @@ -1,2865 +0,0 @@ -<?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="unixclients"> - <title>Adding Domain Member Servers and Clients</title> - - <para><indexterm> - <primary>Open Magazine</primary> - </indexterm><indexterm> - <primary>survey</primary> - </indexterm> - The most frequently discussed Samba subjects over the past 2 years have focused around domain control and printing. - It is well known that Samba is a file and print server. A recent survey conducted by <emphasis>Open Magazine</emphasis> found - that of all respondents, 97 percent use Samba for file and print services, and 68 percent use Samba for Domain Control. See the - <ulink url="http://www.open-mag.com/cgi-bin/opencgi/surveys/survey.cgi?survey_name=samba">Open-Mag</ulink> - Web site for current information. The survey results as found on January 14, 2004, are shown in - <link linkend="ch09openmag"/>. - </para> - - <figure id="ch09openmag"> - <title>Open Magazine Samba Survey</title> - <imagefile scale="60">openmag</imagefile> - </figure> - - <para> - While domain control is an exciting subject, basic file and print sharing remains the staple bread-and-butter - function that Samba provides. Yet this book may give the appearance of having focused too much on more - exciting aspects of Samba deployment. This chapter directs your attention to provide important information on - the addition of Samba servers into your present Windows network &smbmdash; whatever the controlling technology - may be. So let's get back to our good friends at Abmas. - </para> - -<sect1> - <title>Introduction</title> - - <para><indexterm> - <primary>Linux desktop</primary> - </indexterm><indexterm> - <primary>Domain Member</primary> - <secondary>server</secondary> - </indexterm> - Looking back over the achievements of the past year or two, daily events at Abmas are rather straightforward - with not too many distractions or problems. Your team is doing well, but a number of employees - are asking for Linux desktop systems. Your network has grown and demands additional domain member servers. Let's - get on with this; Christine and Stan are ready to go. - </para> - - <para><indexterm> - <primary>Domain Member</primary> - <secondary>desktop</secondary> - </indexterm> - Stan is firmly in control of the department of the future, while Christine is enjoying a stable and - predictable network environment. It is time to add more servers and to add Linux desktops. It is - time to meet the demands of future growth and endure trial by fire. - </para> - - <sect2> - <title>Assignment Tasks</title> - - <para><indexterm> - <primary>Active Directory</primary> - </indexterm> - You must now add UNIX/Linux domain member servers to your network. You have a friend who has a Windows 2003 - Active Directory domain network who wants to add a Samba/Linux server and has asked Christine to help him - out. Your real objective is to help Christine to see more of the way the Microsoft world lives and use - her help to get validation that Samba really does live up to expectations. - </para> - - <para> - Over the past 6 months, you have hired several new staff who want Linux on their desktops. You must integrate - these systems to make sure that Abmas is not building islands of technology. You ask Christine to - do likewise at Swodniw Biz NL (your friend's company) to help them to evaluate a Linux desktop. You want to make - the right decision, don't you? - </para> - - </sect2> -</sect1> - -<sect1> - <title>Dissection and Discussion</title> - - <para> - <indexterm><primary>winbind</primary></indexterm> - Recent Samba mailing-list activity is witness to how many sites are using winbind. Some have no trouble - at all with it, yet to others the problems seem insurmountable. Periodically there are complaints concerning - an inability to achieve identical user and group IDs between Windows and UNIX environments. - </para> - - <para> - You provide step-by-step implementations of the various tools that can be used for identity - resolution. You also provide working examples of solutions for integrated authentication for - both UNIX/Linux and Windows environments. - </para> - - <sect2> - <title>Technical Issues</title> - - <para> - One of the great challenges we face when people ask us, <quote>What is the best way to solve - this problem?</quote> is to get beyond the facts so we not only can clearly comprehend - the immediate technical problem, but also can understand how needs may change. - </para> - - <para> - <indexterm><primary>integrate</primary></indexterm> - There are a few facts we should note when dealing with the question of how best to - integrate UNIX/Linux clients and servers into a Windows networking environment: - </para> - - <itemizedlist> - <listitem><para> - <indexterm><primary>Domain Controller</primary></indexterm> - <indexterm><primary>authoritative</primary></indexterm> - <indexterm><primary>accounts</primary><secondary>authoritative</secondary></indexterm> - <indexterm><primary>PDC</primary></indexterm> - <indexterm><primary>BDC</primary></indexterm> - A domain controller (PDC or BDC) is always authoritative for all accounts in its domain. - This means that a BDC must (of necessity) be able to resolve all account UIDs and GIDs - to the same values that the PDC resolved them to. - </para></listitem> - - <listitem><para> - <indexterm><primary>local accounts</primary></indexterm> - <indexterm><primary>Domain Member</primary><secondary>authoritative</secondary><tertiary>local accounts</tertiary></indexterm> - <indexterm><primary>Domain accounts</primary></indexterm> - <indexterm><primary>winbindd</primary></indexterm> - A domain member can be authoritative for local accounts, but is never authoritative for - domain accounts. If a user is accessing a domain member server and that user's account - is not known locally, the domain member server must resolve the identity of that user - from the domain in which that user's account resides. It must then map that ID to a - UID/GID pair that it can use locally. This is handled by <command>winbindd</command>. - </para></listitem> - - <listitem><para> - Samba, when running on a domain member server, can resolve user identities from a - number of sources: - </para> - - <itemizedlist> - <listitem><para> - <indexterm><primary>getpwnam</primary></indexterm> - <indexterm><primary>getgrnam</primary></indexterm> - <indexterm><primary>NSS</primary></indexterm> - <indexterm><primary>LDAP</primary></indexterm> - <indexterm><primary>NIS</primary></indexterm> - By executing a system <command>getpwnam()</command> or <command>getgrnam()</command> call. - On systems that support it, this utilizes the name service switch (NSS) facility to - resolve names according to the configuration of the <filename>/etc/nsswitch.conf</filename> - file. NSS can be configured to use LDAP, winbind, NIS, or local files. - </para></listitem> - - <listitem><para> - <indexterm><primary>passdb backend</primary></indexterm> - <indexterm><primary>PADL</primary></indexterm> - <indexterm><primary>nss_ldap</primary></indexterm> - Performing, via NSS, a direct LDAP search (where an LDAP passdb backend has been configured). - This requires the use of the PADL nss_ldap tool (or equivalent). - </para></listitem> - - <listitem><para> - <indexterm><primary>winbindd</primary></indexterm> - <indexterm><primary>SID</primary></indexterm> - <indexterm><primary>winbindd_idmap.tdb</primary></indexterm> - <indexterm><primary>winbindd_cache.tdb</primary></indexterm> - Directly by querying <command>winbindd</command>. The <command>winbindd</command> - contacts a domain controller to attempt to resolve the identity of the user or group. It - receives the Windows networking security identifier (SID) for that appropriate - account and then allocates a local UID or GID from the range of available IDs and - creates an entry in its <filename>winbindd_idmap.tdb</filename> and - <filename>winbindd_cache.tdb</filename> files. - </para> - - <para> - <indexterm><primary>idmap backend</primary></indexterm> - <indexterm><primary>mapping</primary></indexterm> - If the parameter <smbconfoption name="idmap backend">ldap:ldap://myserver.domain</smbconfoption> - was specified and the LDAP server has been configured with a container in which it may - store the IDMAP entries, all domain members may share a common mapping. - </para></listitem> - </itemizedlist> - - <para> - Irrespective of how &smb.conf; is configured, winbind creates and caches a local copy of - the ID mapping database. It uses the <filename>winbindd_idmap.tdb</filename> and - <filename>winbindd_cache.tdb</filename> files to do this. - </para> - - <para> - Which of the resolver methods is chosen is determined by the way that Samba is configured - in the &smb.conf; file. Some of the configuration options are rather less than obvious to the - casual user. - </para></listitem> - - <listitem><para> - <indexterm><primary>winbind trusted domains only</primary></indexterm> - <indexterm><primary>domain member</primary><secondary>servers</secondary></indexterm> - <indexterm><primary>domain controllers</primary></indexterm> - If you wish to make use of accounts (users and/or groups) that are local to (i.e., capable - of being resolved using) the NSS facility, it is possible to use the - <smbconfoption name="winbind trusted domains only">Yes</smbconfoption> - in the &smb.conf; file. This parameter specifically applies to domain controllers, - and to domain member servers. - </para></listitem> - - </itemizedlist> - - <para> - <indexterm><primary>Posix accounts</primary></indexterm> - <indexterm><primary>Samba accounts</primary></indexterm> - <indexterm><primary>LDAP</primary></indexterm> - For many administrators, it should be plain that the use of an LDAP-based repository for all network - accounts (both for POSIX accounts and for Samba accounts) provides the most elegant and - controllable facility. You eventually appreciate the decision to use LDAP. - </para> - - <para> - <indexterm><primary>nss_ldap</primary></indexterm> - <indexterm><primary>identifiers</primary></indexterm> - <indexterm><primary>resolve</primary></indexterm> - If your network account information resides in an LDAP repository, you should use it ahead of any - alternative method. This means that if it is humanly possible to use the <command>nss_ldap</command> - tools to resolve UNIX account UIDs/GIDs via LDAP, this is the preferred solution, because it provides - a more readily controllable method for asserting the exact same user and group identifiers - throughout the network. - </para> - - <para> - <indexterm><primary>Domain Member</primary><secondary>server</secondary></indexterm> - <indexterm><primary>winbind trusted domains only</primary></indexterm> - <indexterm><primary>getpwnam</primary></indexterm> - <indexterm><primary>smbd</primary></indexterm> - <indexterm><primary>Trusted Domains</primary></indexterm> - <indexterm><primary>External Domains</primary></indexterm> - In the situation where UNIX accounts are held on the domain member server itself, the only effective - way to use them involves the &smb.conf; entry - <smbconfoption name="winbind trusted domains only">Yes</smbconfoption>. This forces - Samba (<command>smbd</command>) to perform a <command>getpwnam()</command> system call that can - then be controlled via <filename>/etc/nsswitch.conf</filename> file settings. The use of this parameter - disables the use of Samba with trusted domains (i.e., external domains). - </para> - - <para> - <indexterm><primary>appliance mode</primary></indexterm> - <indexterm><primary>Domain Member</primary><secondary>server</secondary></indexterm> - <indexterm><primary>winbindd</primary></indexterm> - <indexterm><primary>automatically allocate</primary></indexterm> - Winbind can be used to create an appliance mode domain member server. In this capacity, <command>winbindd</command> - is configured to automatically allocate UIDs/GIDs from numeric ranges set in the &smb.conf; file. The allocation - is made for all accounts that connect to that domain member server, whether within its own domain or from - trusted domains. If not stored in an LDAP backend, each domain member maintains its own unique mapping database. - This means that it is almost certain that a given user who accesses two domain member servers does not have the - same UID/GID on both servers &smbmdash; however, this is transparent to the Windows network user. This data - is stored in the <filename>winbindd_idmap.tdb</filename> and <filename>winbindd_cache.tdb</filename> files. - </para> - - <para> - <indexterm><primary>mapping</primary></indexterm> - The use of an LDAP backend for the Winbind IDMAP facility permits Windows domain SIDs - mappings to UIDs/GIDs to be stored centrally. The result is a consistent mapping across all domain member - servers so configured. This solves one of the major headaches for network administrators who need to copy - files between or across network file servers. - </para> - - </sect2> - - <sect2> - <title>Political Issues</title> - - <para> - <indexterm><primary>OpenLDAP</primary></indexterm> - <indexterm><primary>NIS</primary></indexterm> - <indexterm><primary>yellow pages</primary><see>NIS</see></indexterm> - <indexterm><primary>identity management</primary></indexterm> - One of the most fierce conflicts recently being waged is resistance to the adoption of LDAP, in - particular OpenLDAP, as a replacement for UNIX NIS (previously called Yellow Pages). Let's face it, LDAP - is different and requires a new approach to the need for a better identity management solution. The more - you work with LDAP, the more its power and flexibility emerges from its dark, cavernous chasm. - </para> - - <para> - LDAP is a most suitable solution for heterogenous environments. If you need crypto, add Kerberos. - The reason these are preferable is because they are heterogenous. Windows solutions of this sort are <emphasis>not</emphasis> - heterogenous by design. This is fundamental &smbmdash; it isn't religious or political. This also doesn't say that - you can't use Windows Active Directory in a heterogenous environment &smbmdash; it can be done, it just requires - commercial integration products. But it's not what Active Directory was designed for. - </para> - - <para> - <indexterm><primary>directory</primary></indexterm> - <indexterm><primary>management</primary></indexterm> - A number of long-term UNIX devotees have recently commented in various communications that the Samba Team - is the first application group to almost force network administrators to use LDAP. It should be pointed - out that we resisted this for as long as we could. It is not out of laziness or malice that LDAP has - finally emerged as the preferred identity management backend for Samba. We recommend LDAP for your total - organizational directory needs. - </para> - - </sect2> - -</sect1> - -<sect1> - <title>Implementation</title> - - <para> - <indexterm><primary>Domain Member</primary><secondary>server</secondary></indexterm> - <indexterm><primary>Domain Member</primary><secondary>client</secondary></indexterm> - <indexterm><primary>Domain Controller</primary></indexterm> - The domain member server and the domain member client are at the center of focus in this chapter. - Configuration of Samba domain controller is covered in earlier chapters, so if your - interest is in domain controller configuration, you will not find that here. You will find good - oil that helps you to add domain member servers and clients. - </para> - - <para> - <indexterm><primary>Domain Member</primary><secondary>workstations</secondary></indexterm> - In practice, domain member servers and domain member workstations are very different entities, but in - terms of technology they share similar core infrastructure. A technologist would argue that servers - and workstations are identical. Many users would argue otherwise, given that in a well-disciplined - environment a workstation (client) is a device from which a user creates documents and files that - are located on servers. A workstation is frequently viewed as a disposable (easy to replace) item, - but a server is viewed as a core component of the business. - </para> - - <para> - <indexterm><primary>workstation</primary></indexterm> - We can look at this another way. If a workstation breaks down, one user is affected, but if a - server breaks down, hundreds of users may not be able to work. The services that a workstation - must provide are document- and file-production oriented; a server provides information storage - and is distribution oriented. - </para> - - <para> - <indexterm><primary>authentication process</primary></indexterm> - <indexterm><primary>logon process</primary></indexterm> - <indexterm><primary>user identities</primary></indexterm> - <emphasis>Why is this important?</emphasis> For starters, we must identify what - components of the operating system and its environment must be configured. Also, it is necessary - to recognize where the interdependencies between the various services to be used are. - In particular, it is important to understand the operation of each critical part of the - authentication process, the logon process, and how user identities get resolved and applied - within the operating system and applications (like Samba) that depend on this and may - actually contribute to it. - </para> - - <para> - So, in this chapter we demonstrate how to implement the technology. It is done within a context of - what type of service need must be fulfilled. - </para> - - <sect2 id="sdcsdmldap"> - <title>Samba Domain with Samba Domain Member Server &smbmdash; Using NSS LDAP</title> - - <para> - <indexterm><primary>ldapsam</primary></indexterm> - <indexterm><primary>ldapsam backend</primary></indexterm> - <indexterm><primary>IDMAP</primary></indexterm> - <indexterm><primary>mapping</primary><secondary>consistent</secondary></indexterm> - <indexterm><primary>winbindd</primary></indexterm> - <indexterm><primary>foreign SID</primary></indexterm> - In this example, it is assumed that you have Samba PDC/BDC servers. This means you are using - an LDAP ldapsam backend. We are adding to the LDAP backend database (directory) - containers for use by the IDMAP facility. This makes it possible to have globally consistent - mapping of SIDs to and from UIDs and GIDs. This means that it is necessary to run - <command>winbindd</command> as part of your configuration. The primary purpose of running - <command>winbindd</command> (within this operational context) is to permit mapping of foreign - SIDs (those not originating from the the local Samba server). Foreign SIDs can come from any - domain member client or server, or from Windows clients that do not belong to a domain. Another - way to explain the necessity to run <command>winbindd</command> is that Samba can locally - resolve only accounts that belong to the security context of its own machine SID. Winbind - handles all non-local SIDs and maps them to a local UID/GID value. The UID and GID are allocated - from the parameter values set in the &smb.conf; file for the <parameter>idmap uid</parameter> and - <parameter>idmap gid</parameter> ranges. Where LDAP is used, the mappings can be stored in LDAP - so that all domain member servers can use a consistent mapping. - </para> - - <para> - <indexterm><primary>winbindd</primary></indexterm> - <indexterm><primary>getpwnam</primary></indexterm> - <indexterm><primary>NSS</primary></indexterm> - If your installation is accessed only from clients that are members of your own domain, and all - user accounts are present in a local passdb backend then it is not necessary to run - <command>winbindd</command>. The local passdb backend can be in smbpasswd, tdbsam, or in ldapsam. - </para> - - <para> - It is possible to use a local passdb backend with any convenient means of resolving the POSIX - user and group account information. The POSIX information is usually obtained using the - <command>getpwnam()</command> system call. On NSS-enabled systems, the actual POSIX account - source can be provided from - </para> - - <itemizedlist> - <listitem><para> - <indexterm><primary>/etc/passwd</primary></indexterm> - <indexterm><primary>/etc/group</primary></indexterm> - Accounts in <filename>/etc/passwd</filename> or in <filename>/etc/group</filename>. - </para></listitem> - - <listitem><para> - <indexterm><primary>NSS</primary></indexterm> - <indexterm><primary>compat</primary></indexterm> - <indexterm><primary>ldap</primary></indexterm> - <indexterm><primary>nis</primary></indexterm> - <indexterm><primary>nisplus</primary></indexterm> - <indexterm><primary>hesiod</primary></indexterm> - <indexterm><primary>ldap</primary></indexterm> - <indexterm><primary>nss_ldap</primary></indexterm> - <indexterm><primary>PADL Software</primary></indexterm> - Resolution via NSS. On NSS-enabled systems, there is usually a facility to resolve IDs - via multiple methods. The methods typically include <command>files</command>, - <command>compat</command>, <command>db</command>, <command>ldap</command>, - <command>nis</command>, <command>nisplus</command>, <command>hesiod.</command> When - correctly installed, Samba adds to this list the <command>winbindd</command> facility. - The ldap facility is frequently the nss_ldap tool provided by PADL Software. - </para></listitem> - </itemizedlist> - - <note><para> - To advoid confusion the use of the term <literal>local passdb backend</literal> means that - the user account backend is not shared by any other Samba server &smbmdash; instead, it is - used only locally on the Samba domain member server under discussion. - </para></note> - - <para> - <indexterm><primary>Identity resolution</primary></indexterm> - The diagram in <link linkend="ch9-sambadc"/> demonstrates the relationship of Samba and system - components that are involved in the identity resolution process where Samba is used as a domain - member server within a Samba domain control network. - </para> - -<figure id="ch9-sambadc"> - <title>Samba Domain: Samba Member Server</title> - <imagefile scale="60">chap9-SambaDC</imagefile> -</figure> - - <para> - <indexterm><primary>IDMAP</primary></indexterm> - <indexterm><primary>foreign</primary></indexterm> - In this example configuration, Samba will directly search the LDAP-based passwd backend ldapsam - to obtain authentication and user identity information. The IDMAP information is stored in the LDAP - backend so that it can be shared by all domain member servers so that every user will have a - consistent UID and GID across all of them. The IDMAP facility will be used for all foreign - (i.e., not having the same SID as the domain it is a member of) domains. The configuration of - NSS will ensure that all UNIX processes will obtain a consistent UID/GID. - </para> - - <para> - The instructions given here apply to the Samba environment shown in <link linkend="happy"/> and <link linkend="net2000users"/>. - If the network does not have an LDAP slave server (i.e., <link linkend="happy"/> configuration), - change the target LDAP server from <constant>lapdc</constant> to <constant>massive.</constant> - </para> - - <procedure> - <title>Configuration of NSS_LDAP-Based Identity Resolution</title> - - <step><para> - Create the &smb.conf; file as shown in <link linkend="ch9-sdmsdc"/>. Locate - this file in the directory <filename>/etc/samba</filename>. - </para></step> - - <step><para> - <indexterm><primary>ldap.conf</primary></indexterm> - Configure the file that will be used by <constant>nss_ldap</constant> to - locate and communicate with the LDAP server. This file is called <filename>ldap.conf</filename>. - If your implementation of <constant>nss_ldap</constant> is consistent with - the defaults suggested by PADL (the authors), it will be located in the - <filename>/etc</filename> directory. On some systems, the default location is - the <filename>/etc/openldap</filename> directory, however this file is intended - for use by the OpenLDAP utilities and should not really be used by the nss_ldap - utility since its content and structure serves the specific purpose of enabling - the resolution of user and group IDs via NSS. - </para> - - <para> - Change the parameters inside the file that is located on your OS so it matches - <link linkend="ch9-sdmlcnf"/>. To find the correct location of this file, you - can obtain this from the library that will be used by executing the following: -<screen> -&rootprompt; strings /lib/libnss_ldap* | grep ldap.conf -/etc/ldap.conf -</screen> - </para></step> - - <step><para> - Configure the NSS control file so it matches the one shown in - <link linkend="ch9-sdmnss"/>. - </para></step> - - <step><para> - <indexterm><primary>Identity resolution</primary></indexterm> - <indexterm><primary>getent</primary></indexterm> - Before proceeding to configure Samba, validate the operation of the NSS identity - resolution via LDAP by executing: -<screen> -&rootprompt; getent passwd -... -root:x:0:512:Netbios Domain Administrator:/root:/bin/false -nobody:x:999:514:nobody:/dev/null:/bin/false -bobj:x:1000:513:Robert Jordan:/home/bobj:/bin/bash -stans:x:1001:513:Stanley Soroka:/home/stans:/bin/bash -chrisr:x:1002:513:Christine Roberson:/home/chrisr:/bin/bash -maryv:x:1003:513:Mary Vortexis:/home/maryv:/bin/bash -jht:x:1004:513:John H Terpstra:/home/jht:/bin/bash -bldg1$:x:1006:553:bldg1$:/dev/null:/bin/false -temptation$:x:1009:553:temptation$:/dev/null:/bin/false -vaioboss$:x:1005:553:vaioboss$:/dev/null:/bin/false -fran$:x:1008:553:fran$:/dev/null:/bin/false -josephj:x:1007:513:Joseph James:/home/josephj:/bin/bash -</screen> - You should notice the location of the users' home directories. First, make certain that - the home directories exist on the domain member server; otherwise, the home directory - share is not available. The home directories could be mounted off a domain controller - using NFS or by any other suitable means. Second, the absence of the domain name in the - home directory path is indicative that identity resolution is not being done via winbind. -<screen> -&rootprompt; getent group -... -Domain Admins:x:512:root,jht -Domain Users:x:513:bobj,stans,chrisr,maryv,jht,josephj -Domain Guests:x:514: -Accounts:x:1000: -Finances:x:1001: -PIOps:x:1002: -sammy:x:4321: -</screen> - <indexterm><primary>secondary group</primary></indexterm> - <indexterm><primary>primary group</primary></indexterm> - <indexterm><primary>group membership</primary></indexterm> - This shows that all is working as it should be. Notice that in the LDAP database - the users' primary and secondary group memberships are identical. It is not - necessary to add secondary group memberships (in the group database) if the - user is already a member via primary group membership in the password database. - When using winbind, it is in fact undesirable to do this because it results in - doubling up of group memberships and may cause problems with winbind under certain - conditions. It is intended that these limitations with winbind will be resolved soon - after Samba-3.0.20 has been released. - </para></step> - - <step><para> - <indexterm><primary>slapcat</primary></indexterm> - The LDAP directory must have a container object for IDMAP data. There are several ways you can - check that your LDAP database is able to receive IDMAP information. One of the simplest is to - execute: -<screen> -&rootprompt; slapcat | grep -i idmap -dn: ou=Idmap,dc=abmas,dc=biz -ou: idmap -</screen> - <indexterm><primary>ldapadd</primary></indexterm> - If the execution of this command does not return IDMAP entries, you need to create an LDIF - template file (see <link linkend="ch9-ldifadd"/>). You can add the required entries using - the following command: -<screen> -&rootprompt; ldapadd -x -D "cn=Manager,dc=abmas,dc=biz" \ - -w not24get < /etc/openldap/idmap.LDIF -</screen> - </para></step> - - <step><para> - Samba automatically populates the LDAP directory container when it needs to. To permit Samba - write access to the LDAP directory it is necessary to set the LDAP administrative password - in the <filename>secrets.tdb</filename> file as shown here: -<screen> -&rootprompt; smbpasswd -w not24get -</screen> - </para></step> - - <step><para> - <indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm> - <indexterm><primary>Domain join</primary></indexterm> - The system is ready to join the domain. Execute the following: -<screen> -&rootprompt; net rpc join -U root%not24get -Joined domain MEGANET2. -</screen> - This indicates that the domain join succeeded. - </para> - - <para> - Failure to join the domain could be caused by any number of variables. The most common - causes of failure to join are: - </para> - - <para> - <itemizedlist> - <listitem><para>Broken resolution of NetBIOS names to the respective IP address.</para></listitem> - <listitem><para>Incorrect username and password credentials.</para></listitem> - <listitem><para>The NT4 <parameter>restrict anonymous</parameter> is set to exclude anonymous - connections.</para></listitem> - </itemizedlist> - </para> - - <para> - The connection setup can be diagnosed by executing: -<screen> -&rootprompt; net rpc join -S 'pdc-name' -U administrator%password -d 5 -</screen> - <indexterm><primary>failed</primary></indexterm> - <indexterm><primary>failed join</primary></indexterm> - <indexterm><primary>rejected</primary></indexterm> - <indexterm><primary>restrict anonymous</primary></indexterm> - Note: Use "root" for UNIX/Linux and Samba, use "Administrator" for Windows NT4/200X. If the cause of - the failure appears to be related to a rejected or failed NT_SESSION_SETUP* or an error message that - says NT_STATUS_ACCESS_DENIED immediately check the Windows registry setting that controls the - <constant>restrict anonymous</constant> setting. Set this to the value 0 so that an anonymous connection - can be sustained, then try again. - </para> - - <para> - It is possible (perhaps even recommended) to use the following to validate the ability to connect - to an NT4 PDC/BDC: -<screen> -&rootprompt; net rpc info -S 'pdc-name' -U Administrator%not24get -Domain Name: MEGANET2 -Domain SID: S-1-5-21-422319763-4138913805-7168186429 -Sequence number: 1519909596 -Num users: 7003 -Num domain groups: 821 -Num local groups: 8 - -&rootprompt; net rpc testjoin -S 'pdc-name' -U Administrator%not24get -Join to 'MEGANET2' is OK -</screen> - If for any reason the following response is obtained to the last command above,it is time to - call in the Networking Super-Snooper task force (i.e., start debugging): -<screen> -NT_STATUS_ACCESS_DENIED -Join to 'MEGANET2' failed. -</screen> - </para></step> - - <step><para> - <indexterm><primary>wbinfo</primary></indexterm> - Just joining the domain is not quite enough; you must now provide a privileged set - of credentials through which <command>winbindd</command> can interact with the - domain servers. Execute the following to implant the necessary credentials: -<screen> -&rootprompt; wbinfo --set-auth-user=Administrator%not24get -</screen> - The configuration is now ready to obtain the Samba domain user and group information. - </para></step> - - <step><para> - You may now start Samba in the usual manner, and your Samba domain member server - is ready for use. Just add shares as required. - </para></step> - - </procedure> - -<example id="ch9-sdmsdc"> -<title>Samba Domain Member in Samba Domain Using LDAP &smbmdash; &smb.conf; File</title> -<smbconfblock> -<smbconfcomment>Global parameters</smbconfcomment> -<smbconfsection name="[global]"/> -<smbconfoption name="unix charset">LOCALE</smbconfoption> -<smbconfoption name="workgroup">MEGANET2</smbconfoption> -<smbconfoption name="security">DOMAIN</smbconfoption> -<smbconfoption name="username map">/etc/samba/smbusers</smbconfoption> -<smbconfoption name="log level">10</smbconfoption> -<smbconfoption name="syslog">0</smbconfoption> -<smbconfoption name="log file">/var/log/samba/%m</smbconfoption> -<smbconfoption name="max log size">50</smbconfoption> -<smbconfoption name="smb ports">139</smbconfoption> -<smbconfoption name="name resolve order">wins bcast hosts</smbconfoption> -<smbconfoption name="printcap name">CUPS</smbconfoption> -<smbconfoption name="wins server">192.168.2.1</smbconfoption> -<smbconfoption name="ldap suffix">dc=abmas,dc=biz</smbconfoption> -<smbconfoption name="ldap machine suffix">ou=People</smbconfoption> -<smbconfoption name="ldap user suffix">ou=People</smbconfoption> -<smbconfoption name="ldap group suffix">ou=Groups</smbconfoption> -<smbconfoption name="ldap idmap suffix">ou=Idmap</smbconfoption> -<smbconfoption name="ldap admin dn">cn=Manager,dc=abmas,dc=biz</smbconfoption> -<smbconfoption name="idmap backend">ldap:ldap://lapdc.abmas.biz</smbconfoption> -<smbconfoption name="idmap uid">10000-20000</smbconfoption> -<smbconfoption name="idmap gid">10000-20000</smbconfoption> -<smbconfoption name="winbind trusted domains only">Yes</smbconfoption> -<smbconfoption name="printing">cups</smbconfoption> - -<smbconfsection name="[homes]"/> -<smbconfoption name="comment">Home Directories</smbconfoption> -<smbconfoption name="valid users">%S</smbconfoption> -<smbconfoption name="read only">No</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[printers]"/> -<smbconfoption name="comment">SMB Print Spool</smbconfoption> -<smbconfoption name="path">/var/spool/samba</smbconfoption> -<smbconfoption name="guest ok">Yes</smbconfoption> -<smbconfoption name="printable">Yes</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[print$]"/> -<smbconfoption name="comment">Printer Drivers</smbconfoption> -<smbconfoption name="path">/var/lib/samba/drivers</smbconfoption> -<smbconfoption name="admin users">root, Administrator</smbconfoption> -<smbconfoption name="write list">root</smbconfoption> -</smbconfblock> -</example> - -<example id="ch9-ldifadd"> -<title>LDIF IDMAP Add-On Load File &smbmdash; File: /etc/openldap/idmap.LDIF</title> -<screen> -dn: ou=Idmap,dc=abmas,dc=biz -objectClass: organizationalUnit -ou: idmap -structuralObjectClass: organizationalUnit -</screen> -</example> - -<example id="ch9-sdmlcnf"> -<title>Configuration File for NSS LDAP Support &smbmdash; <filename>/etc/ldap.conf</filename></title> -<screen> -URI ldap://massive.abmas.biz ldap://massive.abmas.biz:636 -host 192.168.2.1 -base dc=abmas,dc=biz -binddn cn=Manager,dc=abmas,dc=biz -bindpw not24get - -pam_password exop - -nss_base_passwd ou=People,dc=abmas,dc=biz?one -nss_base_shadow ou=People,dc=abmas,dc=biz?one -nss_base_group ou=Groups,dc=abmas,dc=biz?one -ssl no -</screen> -</example> - -<example id="ch9-sdmnss"> -<title>NSS using LDAP for Identity Resolution &smbmdash; File: <filename>/etc/nsswitch.conf</filename></title> -<screen> -passwd: files ldap -shadow: files ldap -group: files ldap - -hosts: files dns wins -networks: files dns - -services: files -protocols: files -rpc: files -ethers: files -netmasks: files -netgroup: files -publickey: files - -bootparams: files -automount: files -aliases: files -</screen> -</example> - - </sect2> - - <sect2 id="wdcsdm"> - <title>NT4/Samba Domain with Samba Domain Member Server: Using NSS and Winbind</title> - - <para> - You need to use this method for creating a Samba domain member server if any of the following conditions - prevail: - </para> - - <itemizedlist> - <listitem><para> - LDAP support (client) is not installed on the system. - </para></listitem> - - <listitem><para> - There are mitigating circumstances forcing a decision not to use LDAP. - </para></listitem> - - <listitem><para> - The Samba domain member server must be part of a Windows NT4 Domain, or a Samba Domain. - </para></listitem> - </itemizedlist> - - <para> - <indexterm><primary>Windows ADS Domain</primary></indexterm> - <indexterm><primary>Samba Domain</primary></indexterm> - <indexterm><primary>LDAP</primary></indexterm> - Later in the chapter, you can see how to configure a Samba domain member server for a Windows ADS domain. - Right now your objective is to configure a Samba server that can be a member of a Windows NT4-style - domain and/or does not use LDAP. - </para> - - <note><para> - <indexterm><primary>duplicate accounts</primary></indexterm> - If you use <command>winbind</command> for identity resolution, make sure that there are no - duplicate accounts. - </para> - - <para> - <indexterm><primary>/etc/passwd</primary></indexterm> - For example, do not have more than one account that has UID=0 in the password database. If there - is an account called <constant>root</constant> in the <filename>/etc/passwd</filename> database, - it is okay to have an account called <constant>root</constant> in the LDAP ldapsam or in the - tdbsam. But if there are two accounts in the passdb backend that have the same UID, winbind will - break. This means that the <constant>Administrator</constant> account must be called - <constant>root</constant>. - </para> - - <para> - <indexterm><primary>/etc/passwd</primary></indexterm> - <indexterm><primary>ldapsam</primary></indexterm> - <indexterm><primary>tdbsam</primary></indexterm> - Winbind will break if there is an account in <filename>/etc/passwd</filename> that has - the same UID as an account that is in LDAP ldapsam (or in tdbsam) but that differs in name only. - </para></note> - - <para> - <indexterm><primary>credentials</primary></indexterm> - <indexterm><primary>traverse</primary></indexterm> - <indexterm><primary>wide-area</primary></indexterm> - <indexterm><primary>network</primary><secondary>wide-area</secondary></indexterm> - <indexterm><primary>tdbdump</primary></indexterm> - The following configuration uses CIFS/SMB protocols alone to obtain user and group credentials. - The winbind information is locally cached in the <filename>winbindd_cache.tdb winbindd_idmap.tdb</filename> - files. This provides considerable performance benefits compared with the LDAP solution, particularly - where the LDAP lookups must traverse WAN links. You may examine the contents of these - files using the tool <command>tdbdump</command>, though you may have to build this from the Samba - source code if it has not been supplied as part of a binary package distribution that you may be using. - </para> - - <procedure> - <title>Configuration of Winbind-Based Identity Resolution</title> - - <step><para> - Using your favorite text editor, create the &smb.conf; file so it has the contents - shown in <link linkend="ch0-NT4DSDM"/>. - </para></step> - - <step><para> - <indexterm><primary>/etc/nsswitch.conf</primary></indexterm> - Edit the <filename>/etc/nsswitch.conf</filename> so it has the entries shown in - <link linkend="ch9-sdmnss"/>. - </para></step> - - <step><para> - <indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm> - The system is ready to join the domain. Execute the following: -<screen> -net rpc join -U root%not2g4et -Joined domain MEGANET2. -</screen> - This indicates that the domain join succeed. - - </para></step> - - <step><para> - <indexterm><primary>winbind</primary></indexterm> - <indexterm><primary>wbinfo</primary></indexterm> - Validate operation of <command>winbind</command> using the <command>wbinfo</command> - tool as follows: -<screen> -&rootprompt; wbinfo -u -MEGANET2+root -MEGANET2+nobody -MEGANET2+jht -MEGANET2+maryv -MEGANET2+billr -MEGANET2+jelliott -MEGANET2+dbrady -MEGANET2+joeg -MEGANET2+balap -</screen> - This shows that domain users have been listed correctly. -<screen> -&rootprompt; wbinfo -g -MEGANET2+Domain Admins -MEGANET2+Domain Users -MEGANET2+Domain Guests -MEGANET2+Accounts -MEGANET2+Finances -MEGANET2+PIOps -</screen> - This shows that domain groups have been correctly obtained also. - </para></step> - - <step><para> - <indexterm><primary>NSS</primary></indexterm> - <indexterm><primary>getent</primary></indexterm> - <indexterm><primary>winbind</primary></indexterm> - The next step verifies that NSS is able to obtain this information - correctly from <command>winbind</command> also. -<screen> -&rootprompt; getent passwd -... -MEGANET2+root:x:10000:10001:NetBIOS Domain Admin: - /home/MEGANET2/root:/bin/bash -MEGANET2+nobody:x:10001:10001:nobody: - /home/MEGANET2/nobody:/bin/bash -MEGANET2+jht:x:10002:10001:John H Terpstra: - /home/MEGANET2/jht:/bin/bash -MEGANET2+maryv:x:10003:10001:Mary Vortexis: - /home/MEGANET2/maryv:/bin/bash -MEGANET2+billr:x:10004:10001:William Randalph: - /home/MEGANET2/billr:/bin/bash -MEGANET2+jelliott:x:10005:10001:John G Elliott: - /home/MEGANET2/jelliott:/bin/bash -MEGANET2+dbrady:x:10006:10001:Darren Brady: - /home/MEGANET2/dbrady:/bin/bash -MEGANET2+joeg:x:10007:10001:Joe Green: - /home/MEGANET2/joeg:/bin/bash -MEGANET2+balap:x:10008:10001:Bala Pillay: - /home/MEGANET2/balap:/bin/bash -</screen> - The user account information has been correctly obtained. This information has - been merged with the winbind template information configured in the &smb.conf; file. -<screen> -&rootprompt;# getent group -... -MEGANET2+Domain Admins:x:10000:MEGANET2+root,MEGANET2+jht -MEGANET2+Domain Users:x:10001:MEGANET2+jht,MEGANET2+maryv,\ - MEGANET2+billr,MEGANET2+jelliott,MEGANET2+dbrady,\ - MEGANET2+joeg,MEGANET2+balap -MEGANET2+Domain Guests:x:10002:MEGANET2+nobody -MEGANET2+Accounts:x:10003: -MEGANET2+Finances:x:10004: -MEGANET2+PIOps:x:10005: -</screen> - </para></step> - - <step><para> - The Samba member server of a Windows NT4 domain is ready for use. - </para></step> - - </procedure> - -<example id="ch0-NT4DSDM"> -<title>Samba Domain Member Server Using Winbind &smb.conf; File for NT4 Domain</title> -<smbconfblock> -<smbconfcomment>Global parameters</smbconfcomment> -<smbconfsection name="[global]"/> -<smbconfoption name="unix charset">LOCALE</smbconfoption> -<smbconfoption name="workgroup">MEGANET2</smbconfoption> -<smbconfoption name="security">DOMAIN</smbconfoption> -<smbconfoption name="username map">/etc/samba/smbusers</smbconfoption> -<smbconfoption name="log level">1</smbconfoption> -<smbconfoption name="syslog">0</smbconfoption> -<smbconfoption name="log file">/var/log/samba/%m</smbconfoption> -<smbconfoption name="max log size">0</smbconfoption> -<smbconfoption name="smb ports">139</smbconfoption> -<smbconfoption name="name resolve order">wins bcast hosts</smbconfoption> -<smbconfoption name="printcap name">CUPS</smbconfoption> -<smbconfoption name="wins server">192.168.2.1</smbconfoption> -<smbconfoption name="idmap uid">10000-20000</smbconfoption> -<smbconfoption name="idmap gid">10000-20000</smbconfoption> -<smbconfoption name="template primary group">"Domain Users"</smbconfoption> -<smbconfoption name="template shell">/bin/bash</smbconfoption> -<smbconfoption name="winbind separator">+</smbconfoption> -<smbconfoption name="hosts allow">192.168.2., 192.168.3., 127.</smbconfoption> -<smbconfoption name="printing">cups</smbconfoption> - -<smbconfsection name="[homes]"/> -<smbconfoption name="comment">Home Directories</smbconfoption> -<smbconfoption name="valid users">%S</smbconfoption> -<smbconfoption name="read only">No</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[printers]"/> -<smbconfoption name="comment">SMB Print Spool</smbconfoption> -<smbconfoption name="path">/var/spool/samba</smbconfoption> -<smbconfoption name="guest ok">Yes</smbconfoption> -<smbconfoption name="printable">Yes</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[print$]"/> -<smbconfoption name="comment">Printer Drivers</smbconfoption> -<smbconfoption name="path">/var/lib/samba/drivers</smbconfoption> -<smbconfoption name="admin users">root, Administrator</smbconfoption> -<smbconfoption name="write list">root</smbconfoption> -</smbconfblock> -</example> - - </sect2> - - <sect2 id="dcwonss"> - <title>NT4/Samba Domain with Samba Domain Member Server without NSS Support</title> - - <para> - No matter how many UNIX/Linux administrators there may be who believe that a UNIX operating - system that does not have NSS and PAM support to be outdated, the fact is there - are still many such systems in use today. Samba can be used without NSS support, but this - does limit it to the use of local user and group accounts only. - </para> - - <para> - The following steps may be followed to implement Samba with support for local accounts. - In this configuration Samba is made a domain member server. All incoming connections - to the Samba server will cause the look-up of the incoming username. If the account - is found, it is used. If the account is not found, one will be automatically created - on the local machine so that it can then be used for all access controls. - </para> - - <procedure> - <title>Configuration Using Local Accounts Only</title> - - <step><para> - Using your favorite text editor, create the &smb.conf; file so it has the contents - shown in <link linkend="ch0-NT4DSCM"/>. - </para></step> - - <step> - <para><indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm> - The system is ready to join the domain. Execute the following: -<screen> -net rpc join -U root%not24get -Joined domain MEGANET2. -</screen> - This indicates that the domain join succeed. - </para></step> - - <step><para> - Be sure to run all three Samba daemons: <command>smbd</command>, <command>nmbd</command>, <command>winbindd</command>. - </para></step> - - <step><para> - The Samba member server of a Windows NT4 domain is ready for use. - </para></step> - </procedure> - -<example id="ch0-NT4DSCM"> -<title>Samba Domain Member Server Using Local Accounts &smb.conf; File for NT4 Domain</title> -<smbconfblock> -<smbconfcomment>Global parameters</smbconfcomment> -<smbconfsection name="[global]"/> -<smbconfoption name="unix charset">LOCALE</smbconfoption> -<smbconfoption name="workgroup">MEGANET3</smbconfoption> -<smbconfoption name="netbios name">BSDBOX</smbconfoption> -<smbconfoption name="security">DOMAIN</smbconfoption> -<smbconfoption name="username map">/etc/samba/smbusers</smbconfoption> -<smbconfoption name="log level">1</smbconfoption> -<smbconfoption name="syslog">0</smbconfoption> -<smbconfoption name="add user script">/usr/sbin/useradd -m '%u'</smbconfoption> -<smbconfoption name="add machine script">/usr/sbin/useradd -M '%u'</smbconfoption> -<smbconfoption name="add group script">/usr/sbin/groupadd '%g'</smbconfoption> -<smbconfoption name="log file">/var/log/samba/%m</smbconfoption> -<smbconfoption name="max log size">0</smbconfoption> -<smbconfoption name="smb ports">139</smbconfoption> -<smbconfoption name="name resolve order">wins bcast hosts</smbconfoption> -<smbconfoption name="printcap name">CUPS</smbconfoption> -<smbconfoption name="wins server">192.168.2.1</smbconfoption> -<smbconfoption name="hosts allow">192.168.2., 192.168.3., 127.</smbconfoption> -<smbconfoption name="printing">cups</smbconfoption> - -<smbconfsection name="[homes]"/> -<smbconfoption name="comment">Home Directories</smbconfoption> -<smbconfoption name="valid users">%S</smbconfoption> -<smbconfoption name="read only">No</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[printers]"/> -<smbconfoption name="comment">SMB Print Spool</smbconfoption> -<smbconfoption name="path">/var/spool/samba</smbconfoption> -<smbconfoption name="guest ok">Yes</smbconfoption> -<smbconfoption name="printable">Yes</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[print$]"/> -<smbconfoption name="comment">Printer Drivers</smbconfoption> -<smbconfoption name="path">/var/lib/samba/drivers</smbconfoption> -<smbconfoption name="admin users">root, Administrator</smbconfoption> -<smbconfoption name="write list">root</smbconfoption> -</smbconfblock> -</example> - </sect2> - - <sect2 id="adssdm"> - <title>Active Directory Domain with Samba Domain Member Server</title> - - <para> - <indexterm><primary>Active Directory</primary><secondary>join</secondary></indexterm> - <indexterm><primary>Kerberos</primary></indexterm> - <indexterm><primary>Domain Member</primary><secondary>server</secondary></indexterm> - One of the much-sought-after features new to Samba is the ability to join an Active Directory - domain using Kerberos protocols. This makes it possible to operate an entire Windows network - without the need to run NetBIOS over TCP/IP and permits more secure networking in general. An - exhaustively complete discussion of the protocols is not possible in this book; perhaps a - later book may explore the intricacies of the NetBIOS-less operation that Samba can participate - in. For now, we simply focus on how a Samba server can be made a domain member server. - </para> - - <para> - <indexterm><primary>Active Directory</primary></indexterm> - <indexterm><primary>LDAP</primary></indexterm> - <indexterm><primary>Identity resolution</primary></indexterm> - <indexterm><primary>Kerberos</primary></indexterm> - The diagram in <link linkend="ch9-adsdc"/> demonstrates how Samba interfaces with - Microsoft Active Directory components. It should be noted that if Microsoft Windows Services - for UNIX (SFU) has been installed and correctly configured, it is possible to use client LDAP - for identity resolution just as can be done with Samba when using an LDAP passdb backend. - The UNIX tool that you need for this, as in the case of LDAP on UNIX/Linux, is the PADL - Software nss_ldap tool-set. Compared with use of winbind and Kerberos, the use of - LDAP-based identity resolution is a little less secure. In view of the fact that this solution - requires additional software to be installed on the Windows 200x ADS domain controllers, - and that means more management overhead, it is likely that most Samba ADS client sites - may elect to use winbind. - </para> - - <para> - Do not attempt to use this procedure if you are not 100 percent certain that the build of Samba - you are using has been compiled and linked with all the tools necessary for this to work. - Given the importance of this step, you must first validate that the Samba message block - daemon (<command>smbd</command>) has the necessary features. - </para> - - <para> - The hypothetical domain you are using in this example assumes that the Abmas London office - decided to take its own lead (some would say this is a typical behavior in a global - corporate world; besides, a little divergence and conflict makes for an interesting life). - The Windows Server 2003 ADS domain is called <constant>london.abmas.biz</constant> and the - name of the server is <constant>W2K3S</constant>. In ADS realm terms, the domain controller - is known as <constant>w2k3s.london.abmas.biz</constant>. In NetBIOS nomenclature, the - domain name is <constant>LONDON</constant> and the server name is <constant>W2K3S</constant>. - </para> - - <figure id="ch9-adsdc"> - <title>Active Directory Domain: Samba Member Server</title> - <imagefile scale="60">chap9-ADSDC</imagefile> - </figure> - - <procedure> - <title>Joining a Samba Server as an ADS Domain Member</title> - - <step><para> - <indexterm><primary>smbd</primary></indexterm> - Before you try to use Samba, you want to know for certain that your executables have - support for Kerberos and for LDAP. Execute the following to identify whether or - not this build is perhaps suitable for use: -<screen> -&rootprompt; cd /usr/sbin -&rootprompt; smbd -b | grep KRB - HAVE_KRB5_H - HAVE_ADDR_TYPE_IN_KRB5_ADDRESS - HAVE_KRB5 - HAVE_KRB5_AUTH_CON_SETKEY - HAVE_KRB5_GET_DEFAULT_IN_TKT_ETYPES - HAVE_KRB5_GET_PW_SALT - HAVE_KRB5_KEYBLOCK_KEYVALUE - HAVE_KRB5_KEYTAB_ENTRY_KEYBLOCK - HAVE_KRB5_MK_REQ_EXTENDED - HAVE_KRB5_PRINCIPAL_GET_COMP_STRING - HAVE_KRB5_SET_DEFAULT_IN_TKT_ETYPES - HAVE_KRB5_STRING_TO_KEY - HAVE_KRB5_STRING_TO_KEY_SALT - HAVE_LIBKRB5 -</screen> - This output was obtained on a SUSE Linux system and shows the output for - Samba that has been compiled and linked with the Heimdal Kerberos libraries. - The following is a typical output that will be found on a Red Hat Linux system that - has been linked with the MIT Kerberos libraries: -<screen> -&rootprompt; cd /usr/sbin -&rootprompt; smbd -b | grep KRB - HAVE_KRB5_H - HAVE_ADDRTYPE_IN_KRB5_ADDRESS - HAVE_KRB5 - HAVE_KRB5_AUTH_CON_SETUSERUSERKEY - HAVE_KRB5_ENCRYPT_DATA - HAVE_KRB5_FREE_DATA_CONTENTS - HAVE_KRB5_FREE_KTYPES - HAVE_KRB5_GET_PERMITTED_ENCTYPES - HAVE_KRB5_KEYTAB_ENTRY_KEY - HAVE_KRB5_LOCATE_KDC - HAVE_KRB5_MK_REQ_EXTENDED - HAVE_KRB5_PRINCIPAL2SALT - HAVE_KRB5_PRINC_COMPONENT - HAVE_KRB5_SET_DEFAULT_TGS_KTYPES - HAVE_KRB5_SET_REAL_TIME - HAVE_KRB5_STRING_TO_KEY - HAVE_KRB5_TKT_ENC_PART2 - HAVE_KRB5_USE_ENCTYPE - HAVE_LIBGSSAPI_KRB5 - HAVE_LIBKRB5 -</screen> - You can validate that Samba has been compiled and linked with LDAP support - by executing: -<screen> -&rootprompt; smbd -b | grep LDAP -massive:/usr/sbin # smbd -b | grep LDAP - HAVE_LDAP_H - HAVE_LDAP - HAVE_LDAP_DOMAIN2HOSTLIST - HAVE_LDAP_INIT - HAVE_LDAP_INITIALIZE - HAVE_LDAP_SET_REBIND_PROC - HAVE_LIBLDAP - LDAP_SET_REBIND_PROC_ARGS -</screen> - This does look promising; <command>smbd</command> has been built with Kerberos and LDAP - support. You are relieved to know that it is safe to progress. - </para></step> - - <step><para> - <indexterm><primary>Kerberos</primary><secondary>libraries</secondary></indexterm> - <indexterm><primary>MIT Kerberos</primary></indexterm> - <indexterm><primary>Heimdal Kerberos</primary></indexterm> - <indexterm><primary>Kerberos</primary><secondary>MIT</secondary></indexterm> - <indexterm><primary>Kerberos</primary><secondary>Heimdal</secondary></indexterm> - <indexterm><primary>Red Hat Linux</primary></indexterm> - <indexterm><primary>SUSE Linux</primary></indexterm> - <indexterm><primary>SerNet</primary></indexterm> - <indexterm><primary>validated</primary></indexterm> - The next step is to identify which version of the Kerberos libraries have been used. - In order to permit Samba to interoperate with Windows 2003 Active Directory, it is - essential that it has been linked with either MIT Kerberos version 1.3.1 or later, - or that it has been linked with Heimdal Kerberos 0.6 plus specific patches. You may - identify what version of the MIT Kerberos libraries are installed on your system by - executing (on Red Hat Linux): -<screen> -&rootprompt; rpm -q krb5 -</screen> - Or on SUSE Linux, execute: -<screen> -&rootprompt; rpm -q heimdal -</screen> - Please note that the RPMs provided by the Samba-Team are known to be working and have - been validated. Red Hat Linux RPMs may be obtained from the Samba FTP sites. SUSE - Linux RPMs may be obtained from <ulink url="ftp://ftp.sernet.de">Sernet</ulink> in - Germany. - </para> - - <para> - From this point on, you are certain that the Samba build you are using has the - necessary capabilities. You can now configure Samba and the NSS. - </para></step> - - <step><para> - Using you favorite editor, configure the &smb.conf; file that is located in the - <filename>/etc/samba</filename> directory so that it has the contents shown - in <link linkend="ch9-adssdm"/>. - </para></step> - - <step><para> - Edit or create the NSS control file so it has the contents shown in <link linkend="ch9-sdmnss"/>. - </para></step> - - <step><para> - <indexterm><primary>/etc/samba/secrets.tdb</primary></indexterm> - Delete the file <filename>/etc/samba/secrets.tdb</filename> if it exists. Of course, you - do keep a backup, don't you? - </para></step> - - <step><para> - Delete the tdb files that cache Samba information. You keep a backup of the old - files, of course. You also remove all files to ensure that nothing can pollute your - nice, new configuration. Execute the following (example is for SUSE Linux): -<screen> -&rootprompt; rm /var/lib/samba/*tdb -</screen> - </para></step> - - <step><para> - <indexterm><primary>testparm</primary></indexterm> - Validate your &smb.conf; file using <command>testparm</command> (as you have - done previously). Correct all errors reported before proceeding. The command you - execute is: -<screen> -&rootprompt; testparm -s | less -</screen> - Now that you are satisfied that your Samba server is ready to join the Windows - ADS domain, let's move on. - </para></step> - - <step><para> - <indexterm><primary>net</primary><secondary>ads</secondary><tertiary>join</tertiary></indexterm> - <indexterm><primary>Kerberos</primary></indexterm> - This is a good time to double-check everything and then execute the following - command when everything you have done has checked out okay: -<screen> -&rootprompt; net ads join -UAdministrator%not24get -Using short domain name -- LONDON -Joined 'FRAN' to realm 'LONDON.ABMAS.BIZ' -</screen> - You have successfully made your Samba server a member of the ADS domain - using Kerberos protocols. - </para> - - <para> - <indexterm><primary>silent return</primary></indexterm> - <indexterm><primary>failed join</primary></indexterm> - In the event that you receive no output messages, a silent return means that the - domain join failed. You should use <command>ethereal</command> to identify what - may be failing. Common causes of a failed join include: - - <itemizedlist> - <listitem><para> - <indexterm><primary>name resolution</primary><secondary>Defective</secondary></indexterm> - Defective or misconfigured DNS name resolution. - </para></listitem> - - <listitem><para> - <indexterm><primary>Restrictive security</primary></indexterm> - Restrictive security settings on the Windows 200x ADS domain controller - preventing needed communications protocols. You can check this by searching - the Windows Server 200x Event Viewer. - </para></listitem> - - <listitem><para> - Incorrectly configured &smb.conf; file settings. - </para></listitem> - - <listitem><para> - Lack of support of necessary Kerberos protocols because the version of MIT - Kerberos (or Heimdal) in use is not up to date enough to support the necessary - functionality. - </para></listitem> - </itemizedlist> - - <indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm> - <indexterm><primary>RPC</primary></indexterm> - <indexterm><primary>mixed mode</primary></indexterm> - In any case, never execute the <command>net rpc join</command> command in an attempt - to join the Samba server to the domain, unless you wish not to use the Kerberos - security protocols. Use of the older RPC-based domain join facility requires that - Windows Server 200x ADS has been configured appropriately for mixed mode operation. - </para></step> - - <step><para> - <indexterm><primary>tdbdump</primary></indexterm> - <indexterm><primary>/etc/samba/secrets.tdb</primary></indexterm> - If the <command>tdbdump</command> is installed on your system (not essential), - you can look inside the <filename>/etc/samba/secrets.tdb</filename> file. If - you wish to do this, execute: -<screen> -&rootprompt; tdbdump secrets.tdb -{ -key = "SECRETS/SID/LONDON" -data = "\01\04\00\00\00\00\00\05\15\00\00\00\EBw\86\F1\ED\BD\ - F6{\5C6\E5W\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\ - 00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\00\ - 00\00\00\00\00\00\00\00" -} -{ -key = "SECRETS/MACHINE_PASSWORD/LONDON" -data = "le3Q5FPnN5.ueC\00" -} -{ -key = "SECRETS/MACHINE_SEC_CHANNEL_TYPE/LONDON" -data = "\02\00\00\00" -} -{ -key = "SECRETS/MACHINE_LAST_CHANGE_TIME/LONDON" -data = "E\89\F6?" -} -</screen> - This is given to demonstrate to the skeptics that this process truly does work. - </para></step> - - <step><para> - It is now time to start Samba in the usual way (as has been done many time before - in this book). - </para></step> - - <step><para> - <indexterm><primary>wbinfo</primary></indexterm> - This is a good time to verify that everything is working. First, check that - winbind is able to obtain the list of users and groups from the ADS domain controller. - Execute the following: -<screen> -&rootprompt; wbinfo -u -LONDON+Administrator -LONDON+Guest -LONDON+SUPPORT_388945a0 -LONDON+krbtgt -LONDON+jht -</screen> - Good, the list of users was obtained. Now do likewise for group accounts: -<screen> -&rootprompt; wbinfo -g -LONDON+Domain Computers -LONDON+Domain Controllers -LONDON+Schema Admins -LONDON+Enterprise Admins -LONDON+Domain Admins -LONDON+Domain Users -LONDON+Domain Guests -LONDON+Group Policy Creator Owners -LONDON+DnsUpdateProxy -</screen> - Excellent. That worked also, as expected. - </para></step> - - <step><para><indexterm> - <primary>getent</primary> - </indexterm> - Now repeat this via NSS to validate that full identity resolution is - functional as required. Execute: -<screen> -&rootprompt; getent passwd -... -LONDON+Administrator:x:10000:10000:Administrator: - /home/LONDON/administrator:/bin/bash -LONDON+Guest:x:10001:10001:Guest: - /home/LONDON/guest:/bin/bash -LONDON+SUPPORT_388945a0:x:10002:10000:SUPPORT_388945a0: - /home/LONDON/support_388945a0:/bin/bash -LONDON+krbtgt:x:10003:10000:krbtgt: - /home/LONDON/krbtgt:/bin/bash -LONDON+jht:x:10004:10000:John H. Terpstra: - /home/LONDON/jht:/bin/bash -</screen> - Okay, ADS user accounts are being resolved. Now you try group resolution: -<screen> -&rootprompt; getent group -... -LONDON+Domain Computers:x:10002: -LONDON+Domain Controllers:x:10003: -LONDON+Schema Admins:x:10004:LONDON+Administrator -LONDON+Enterprise Admins:x:10005:LONDON+Administrator -LONDON+Domain Admins:x:10006:LONDON+jht,LONDON+Administrator -LONDON+Domain Users:x:10000: -LONDON+Domain Guests:x:10001: -LONDON+Group Policy Creator Owners:x:10007:LONDON+Administrator -LONDON+DnsUpdateProxy:x:10008: -</screen> - This is very pleasing. Everything works as expected. - </para></step> - - <step><para> - <indexterm><primary>net</primary><secondary>ads</secondary><tertiary>info</tertiary></indexterm> - <indexterm><primary>Active Directory</primary><secondary>server</secondary></indexterm> - <indexterm><primary>Kerberos</primary></indexterm> - You may now perform final verification that communications between Samba winbind and - the Active Directory server is using Kerberos protocols. Execute the following: -<screen> -&rootprompt; net ads info -LDAP server: 192.168.2.123 -LDAP server name: w2k3s -Realm: LONDON.ABMAS.BIZ -Bind Path: dc=LONDON,dc=ABMAS,dc=BIZ -LDAP port: 389 -Server time: Sat, 03 Jan 2004 02:44:44 GMT -KDC server: 192.168.2.123 -Server time offset: 2 -</screen> - It should be noted that Kerberos protocols are time-clock critical. You should - keep all server time clocks synchronized using the network time protocol (NTP). - In any case, the output we obtained confirms that all systems are operational. - </para></step> - - <step><para> - <indexterm><primary>net</primary><secondary>ads</secondary><tertiary>status</tertiary></indexterm> - There is one more action you elect to take, just because you are paranoid and disbelieving, - so you execute the following command: -<programlisting> -&rootprompt; net ads status -UAdministrator%not24get -objectClass: top -objectClass: person -objectClass: organizationalPerson -objectClass: user -objectClass: computer -cn: fran -distinguishedName: CN=fran,CN=Computers,DC=london,DC=abmas,DC=biz -instanceType: 4 -whenCreated: 20040103092006.0Z -whenChanged: 20040103092006.0Z -uSNCreated: 28713 -uSNChanged: 28717 -name: fran -objectGUID: 58f89519-c467-49b9-acb0-f099d73696e -userAccountControl: 69632 -badPwdCount: 0 -codePage: 0 -countryCode: 0 -badPasswordTime: 0 -lastLogoff: 0 -lastLogon: 127175965783327936 -localPolicyFlags: 0 -pwdLastSet: 127175952062598496 -primaryGroupID: 515 -objectSid: S-1-5-21-4052121579-2079768045-1474639452-1109 -accountExpires: 9223372036854775807 -logonCount: 13 -sAMAccountName: fran$ -sAMAccountType: 805306369 -operatingSystem: Samba -operatingSystemVersion: 3.0.20-SUSE -dNSHostName: fran -userPrincipalName: HOST/fran@LONDON.ABMAS.BIZ -servicePrincipalName: CIFS/fran.london.abmas.biz -servicePrincipalName: CIFS/fran -servicePrincipalName: HOST/fran.london.abmas.biz -servicePrincipalName: HOST/fran -objectCategory: CN=Computer,CN=Schema,CN=Configuration, - DC=london,DC=abmas,DC=biz -isCriticalSystemObject: FALSE --------------- Security Descriptor (revision: 1, type: 0x8c14) -owner SID: S-1-5-21-4052121579-2079768045-1474639452-512 -group SID: S-1-5-21-4052121579-2079768045-1474639452-513 -------- (system) ACL (revision: 4, size: 120, number of ACEs: 2) -------- ACE (type: 0x07, flags: 0x5a, size: 0x38, - mask: 0x20, object flags: 0x3) -access SID: S-1-1-0 -access type: AUDIT OBJECT -Permissions: - [Write All Properties] -------- ACE (type: 0x07, flags: 0x5a, size: 0x38, - mask: 0x20, object flags: 0x3) -access SID: S-1-1-0 -access type: AUDIT OBJECT -Permissions: - [Write All Properties] -------- (user) ACL (revision: 4, size: 1944, number of ACEs: 40) -------- ACE (type: 0x00, flags: 0x00, size: 0x24, mask: 0xf01ff) -access SID: S-1-5-21-4052121579-2079768045-1474639452-512 -access type: ALLOWED -Permissions: [Full Control] -------- ACE (type: 0x00, flags: 0x00, size: 0x18, mask: 0xf01ff) -access SID: S-1-5-32-548 -... -------- ACE (type: 0x05, flags: 0x12, size: 0x38, - mask: 0x10, object flags: 0x3) -access SID: S-1-5-9 -access type: ALLOWED OBJECT -Permissions: - [Read All Properties] --------------- End Of Security Descriptor -</programlisting> - And now you have conclusive proof that your Samba ADS domain member server - called <constant>FRAN</constant> is able to communicate fully with the ADS - domain controllers. - </para></step> - - </procedure> - - - <para> - Your Samba ADS domain member server is ready for use. During training sessions, - you may be asked what is inside the <filename>winbindd_cache.tdb and winbindd_idmap.tdb</filename> - files. Since curiosity just took hold of you, execute the following: -<programlisting> -&rootprompt; tdbdump /var/lib/samba/winbindd_idmap.tdb -{ -key = "S-1-5-21-4052121579-2079768045-1474639452-501\00" -data = "UID 10001\00" -} -{ -key = "UID 10005\00" -data = "S-1-5-21-4052121579-2079768045-1474639452-1111\00" -} -{ -key = "GID 10004\00" -data = "S-1-5-21-4052121579-2079768045-1474639452-518\00" -} -{ -key = "S-1-5-21-4052121579-2079768045-1474639452-502\00" -data = "UID 10003\00" -} -... - -&rootprompt; tdbdump /var/lib/samba/winbindd_cache.tdb -{ -key = "UL/LONDON" -data = "\00\00\00\00bp\00\00\06\00\00\00\0DAdministrator\0D - Administrator-S-1-5-21-4052121579-2079768045-1474639452-500- - S-1-5-21-4052121579-2079768045-1474639452-513\05Guest\05 - Guest-S-1-5-21-4052121579-2079768045-1474639452-501- - S-1-5-21-4052121579-2079768045-1474639452-514\10 - SUPPORT_388945a0\10SUPPORT_388945a0. - S-1-5-21-4052121579-2079768045-1474639452-1001- - S-1-5-21-4052121579-2079768045-1474639452-513\06krbtgt\06 - krbtgt-S-1-5-21-4052121579-2079768045-1474639452-502- - S-1-5-21-4052121579-2079768045-1474639452-513\03jht\10 - John H. Terpstra.S-1-5-21-4052121579-2079768045-1474639452-1110- - S-1-5-21-4052121579-2079768045-1474639452-513" -} -{ -key = "GM/S-1-5-21-4052121579-2079768045-1474639452-512" -data = "\00\00\00\00bp\00\00\02\00\00\00. - S-1-5-21-4052121579-2079768045-1474639452-1110\03 - jht\01\00\00\00-S-1-5-21-4052121579-2079768045-1474639452-500\0D - Administrator\01\00\00\00" -} -{ -key = "SN/S-1-5-21-4052121579-2079768045-1474639452-513" -data = "\00\00\00\00xp\00\00\02\00\00\00\0CDomain Users" -} -{ -key = "GM/S-1-5-21-4052121579-2079768045-1474639452-518" -data = "\00\00\00\00bp\00\00\01\00\00\00- - S-1-5-21-4052121579-2079768045-1474639452-500\0D - Administrator\01\00\00\00" -} -{ -key = "SEQNUM/LONDON\00" -data = "xp\00\00C\92\F6?" -} -{ -key = "U/S-1-5-21-4052121579-2079768045-1474639452-1110" -data = "\00\00\00\00xp\00\00\03jht\10John H. Terpstra. - S-1-5-21-4052121579-2079768045-1474639452-1110- - S-1-5-21-4052121579-2079768045-1474639452-513" -} -{ -key = "NS/S-1-5-21-4052121579-2079768045-1474639452-502" -data = "\00\00\00\00bp\00\00- - S-1-5-21-4052121579-2079768045-1474639452-502" -} -{ -key = "SN/S-1-5-21-4052121579-2079768045-1474639452-1001" -data = "\00\00\00\00bp\00\00\01\00\00\00\10SUPPORT_388945a0" -} -{ -key = "SN/S-1-5-21-4052121579-2079768045-1474639452-500" -data = "\00\00\00\00bp\00\00\01\00\00\00\0DAdministrator" -} -{ -key = "U/S-1-5-21-4052121579-2079768045-1474639452-502" -data = "\00\00\00\00bp\00\00\06krbtgt\06krbtgt- - S-1-5-21-4052121579-2079768045-1474639452-502- - S-1-5-21-4052121579-2079768045-1474639452-513" -} -.... -</programlisting> - Now all is revealed. Your curiosity, as well as that of your team, has been put at ease. - May this server serve well all who happen upon it. - </para> - -<example id="ch9-adssdm"> -<title>Samba Domain Member &smb.conf; File for Active Directory Membership</title> -<smbconfblock> -<smbconfcomment>Global parameters</smbconfcomment> -<smbconfsection name="[global]"/> -<smbconfoption name="unix charset">LOCALE</smbconfoption> -<smbconfoption name="workgroup">LONDON</smbconfoption> -<smbconfoption name="realm">LONDON.ABMAS.BIZ</smbconfoption> -<smbconfoption name="server string">Samba 3.0.20</smbconfoption> -<smbconfoption name="security">ADS</smbconfoption> -<smbconfoption name="username map">/etc/samba/smbusers</smbconfoption> -<smbconfoption name="log level">1</smbconfoption> -<smbconfoption name="syslog">0</smbconfoption> -<smbconfoption name="log file">/var/log/samba/%m</smbconfoption> -<smbconfoption name="max log size">50</smbconfoption> -<smbconfoption name="printcap name">CUPS</smbconfoption> -<smbconfoption name="ldap ssl">no</smbconfoption> -<smbconfoption name="idmap uid">10000-20000</smbconfoption> -<smbconfoption name="idmap gid">10000-20000</smbconfoption> -<smbconfoption name="template primary group">"Domain Users"</smbconfoption> -<smbconfoption name="template shell">/bin/bash</smbconfoption> -<smbconfoption name="winbind separator">+</smbconfoption> -<smbconfoption name="printing">cups</smbconfoption> - -<smbconfsection name="[homes]"/> -<smbconfoption name="comment">Home Directories</smbconfoption> -<smbconfoption name="valid users">%S</smbconfoption> -<smbconfoption name="read only">No</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[printers]"/> -<smbconfoption name="comment">SMB Print Spool</smbconfoption> -<smbconfoption name="path">/var/spool/samba</smbconfoption> -<smbconfoption name="guest ok">Yes</smbconfoption> -<smbconfoption name="printable">Yes</smbconfoption> -<smbconfoption name="browseable">No</smbconfoption> - -<smbconfsection name="[print$]"/> -<smbconfoption name="comment">Printer Drivers</smbconfoption> -<smbconfoption name="path">/var/lib/samba/drivers</smbconfoption> -<smbconfoption name="admin users">root, Administrator</smbconfoption> -<smbconfoption name="write list">root</smbconfoption> -</smbconfblock> -</example> - - <sect3> - <title>IDMAP_RID with Winbind</title> - - <para> - <indexterm><primary>idmap_rid</primary></indexterm> - <indexterm><primary>SID</primary></indexterm> - <indexterm><primary>RID</primary></indexterm> - <indexterm><primary>IDMAP</primary></indexterm> - The <command>idmap_rid</command> facility is a new tool that, unlike native winbind, creates a - predictable mapping of MS Windows SIDs to UNIX UIDs and GIDs. The key benefit of this method - of implementing the Samba IDMAP facility is that it eliminates the need to store the IDMAP data - in a central place. The downside is that it can be used only within a single ADS domain and - is not compatible with trusted domain implementations. - </para> - - <para> - <indexterm><primary>SID</primary></indexterm> - <indexterm><primary>allow trusted domains</primary></indexterm> - <indexterm><primary>idmap uid</primary></indexterm> - <indexterm><primary>idmap gid</primary></indexterm> - This alternate method of SID to UID/GID mapping can be achieved with the idmap_rid - plug-in. This plug-in uses the RID of the user SID to derive the UID and GID by adding the - RID to a base value specified. This utility requires that the parameter - <quote>allow trusted domains = No</quote> must be specified, as it is not compatible - with multiple domain environments. The <parameter>idmap uid</parameter> and - <parameter>idmap gid</parameter> ranges must be specified. - </para> - - <para> - <indexterm><primary>idmap_rid</primary></indexterm> - <indexterm><primary>realm</primary></indexterm> - The idmap_rid facility can be used both for NT4/Samba-style domains as well as with Active Directory. - To use this with an NT4 domain, the <parameter>realm</parameter> is not used. Additionally the - method used to join the domain uses the <constant>net rpc join</constant> process. - </para> - - <para> - An example &smb.conf; file for an ADS domain environment is shown in <link linkend="sbe-idmapridex"/>. - </para> - -<example id="sbe-idmapridex"> -<title>Example &smb.conf; File Using <constant>idmap_rid</constant></title> -<smbconfblock> -<smbconfcomment>Global parameters</smbconfcomment> -<smbconfsection name="[global]"/> -<smbconfoption name="workgroup">KPAK</smbconfoption> -<smbconfoption name="netbios name">BIGJOE</smbconfoption> -<smbconfoption name="realm">CORP.KPAK.COM</smbconfoption> -<smbconfoption name="server string">Office Server</smbconfoption> -<smbconfoption name="security">ADS</smbconfoption> -<smbconfoption name="allow trusted domains">No</smbconfoption> -<smbconfoption name="idmap backend">idmap_rid:KPAK=500-100000000</smbconfoption> -<smbconfoption name="idmap uid">500-100000000</smbconfoption> -<smbconfoption name="idmap gid">500-100000000</smbconfoption> -<smbconfoption name="template shell">/bin/bash</smbconfoption> -<smbconfoption name="winbind use default domain">Yes</smbconfoption> -<smbconfoption name="winbind enum users">No</smbconfoption> -<smbconfoption name="winbind enum groups">No</smbconfoption> -<smbconfoption name="winbind nested groups">Yes</smbconfoption> -</smbconfblock> -</example> - - <para> - <indexterm><primary>large domain</primary></indexterm> - <indexterm><primary>Active Directory</primary></indexterm> - <indexterm><primary>response</primary></indexterm> - <indexterm><primary>getent</primary></indexterm> - In a large domain with many users, it is imperative to disable enumeration of users and groups. - For example, at a site that has 22,000 users in Active Directory the winbind-based user and - group resolution is unavailable for nearly 12 minutes following first start-up of - <command>winbind</command>. Disabling of such enumeration results in instantaneous response. - The disabling of user and group enumeration means that it will not be possible to list users - or groups using the <command>getent passwd</command> and <command>getent group</command> - commands. It will be possible to perform the lookup for individual users, as shown in the procedure - below. - </para> - - <para> - <indexterm><primary>NSS</primary></indexterm> - <indexterm><primary>/etc/nsswitch.conf</primary></indexterm> - The use of this tool requires configuration of NSS as per the native use of winbind. Edit the - <filename>/etc/nsswitch.conf</filename> so it has the following parameters: -<screen> -... -passwd: files winbind -shadow: files winbind -group: files winbind -... -hosts: files wins -... -</screen> - </para> - - <para> - The following procedure can be used to utilize the idmap_rid facility: - </para> - - <procedure> - <step><para> - Create or install and &smb.conf; file with the above configuration. - </para></step> - - <step><para> - Edit the <filename>/etc/nsswitch.conf</filename> file as shown above. - </para></step> - - <step><para> - Execute: -<screen> -&rootprompt; net ads join -UAdministrator%password -Using short domain name -- KPAK -Joined 'BIGJOE' to realm 'CORP.KPAK.COM' -</screen> - </para> - - <para> - <indexterm><primary>failed join</primary></indexterm> - An invalid or failed join can be detected by executing: -<screen> -&rootprompt; net ads testjoin -BIGJOE$@'s password: -[2004/11/05 16:53:03, 0] utils/net_ads.c:ads_startup(186) - ads_connect: No results returned -Join to domain is not valid -</screen> - The specific error message may differ from the above because it depends on the type of failure that - may have occurred. Increase the <parameter>log level</parameter> to 10, repeat the above test, - and then examine the log files produced to identify the nature of the failure. - </para></step> - - <step><para> - Start the <command>nmbd</command>, <command>winbind,</command> and <command>smbd</command> daemons in the order shown. - </para></step> - - <step><para> - Validate the operation of this configuration by executing: - <indexterm><primary></primary></indexterm> -<screen> -&rootprompt; getent passwd administrator -administrator:x:1000:1013:Administrator:/home/BE/administrator:/bin/bash -</screen> - </para></step> - </procedure> - - </sect3> - - <sect3> - <title>IDMAP Storage in LDAP using Winbind</title> - - <para> - <indexterm><primary>ADAM</primary></indexterm> - <indexterm><primary>ADS</primary></indexterm> - The storage of IDMAP information in LDAP can be used with both NT4/Samba-style domains as well as - with ADS domains. OpenLDAP is a commonly used LDAP server for this purpose, although any standards-compliant - LDAP server can be used. It is therefore possible to deploy this IDMAP configuration using - the Sun iPlanet LDAP server, Novell eDirectory, Microsoft ADS plus ADAM, and so on. - </para> - - <para> - The example in <link linkend="sbeunxa"/> is for an ADS-style domain. - </para> - -<example id="sbeunxa"> -<title>Typical ADS Style Domain &smb.conf; File</title> -<smbconfblock> -<smbconfcomment>Global parameters</smbconfcomment> -<smbconfsection name="[global]"/> -<smbconfoption name="workgroup">SNOWSHOW</smbconfoption> -<smbconfoption name="netbios name">GOODELF</smbconfoption> -<smbconfoption name="realm">SNOWSHOW.COM</smbconfoption> -<smbconfoption name="server string">Samba Server</smbconfoption> -<smbconfoption name="security">ADS</smbconfoption> -<smbconfoption name="log level">1 ads:10 auth:10 sam:10 rpc:10</smbconfoption> -<smbconfoption name="ldap admin dn">cn=Manager,dc=SNOWSHOW,dc=COM</smbconfoption> -<smbconfoption name="ldap idmap suffix">ou=Idmap</smbconfoption> -<smbconfoption name="ldap suffix">dc=SNOWSHOW,dc=COM</smbconfoption> -<smbconfoption name="idmap backend">ldap:ldap://ldap.snowshow.com</smbconfoption> -<smbconfoption name="idmap uid">150000-550000</smbconfoption> -<smbconfoption name="idmap gid">150000-550000</smbconfoption> -<smbconfoption name="template shell">/bin/bash</smbconfoption> -<smbconfoption name="winbind use default domain">Yes</smbconfoption> -</smbconfblock> -</example> - - <para> - <indexterm><primary>realm</primary></indexterm> - In the case of an NT4 or Samba-style domain the <parameter>realm</parameter> is not used, and the - command used to join the domain is <command>net rpc join</command>. The above example also demonstrates - advanced error reporting techniques that are documented in the chapter called "Reporting Bugs" in - <quote>The Official Samba HOWTO and Reference Guide, Second Edition</quote> (TOSHARG2). - </para> - - <para> - <indexterm><primary>MIT kerberos</primary></indexterm> - <indexterm><primary>Heimdal kerberos</primary></indexterm> - <indexterm><primary>/etc/krb5.conf</primary></indexterm> - Where MIT kerberos is installed (version 1.3.4 or later), edit the <filename>/etc/krb5.conf</filename> - file so it has the following contents: -<screen> -[logging] - default = FILE:/var/log/krb5libs.log - kdc = FILE:/var/log/krb5kdc.log - admin_server = FILE:/var/log/kadmind.log - -[libdefaults] - default_realm = SNOWSHOW.COM - dns_lookup_realm = false - dns_lookup_kdc = true - -[appdefaults] - pam = { - debug = false - ticket_lifetime = 36000 - renew_lifetime = 36000 - forwardable = true - krb4_convert = false - } -</screen> - </para> - - <para> - Where Heimdal kerberos is installed, edit the <filename>/etc/krb5.conf</filename> - file so it is either empty (i.e., no contents) or it has the following contents: -<screen> -[libdefaults] - default_realm = SNOWSHOW.COM - clockskew = 300 - -[realms] - SNOWSHOW.COM = { - kdc = ADSDC.SHOWSHOW.COM - } - -[domain_realm] - .snowshow.com = SNOWSHOW.COM -</screen> - </para> - - <note><para> - Samba cannot use the Heimdal libraries if there is no <filename>/etc/krb5.conf</filename> file. - So long as there is an empty file, the Heimdal kerberos libraries will be usable. There is no - need to specify any settings because Samba, using the Heimdal libraries, can figure this out automatically. - </para></note> - <para> - Edit the NSS control file <filename>/etc/nsswitch.conf</filename> so it has the following entries: -<screen> -... -passwd: files ldap -shadow: files ldap -group: files ldap -... -hosts: files wins -... -</screen> - </para> - - <para> - <indexterm><primary>PADL</primary></indexterm> - <indexterm><primary>/etc/ldap.conf</primary></indexterm> - You will need the <ulink url="http://www.padl.com">PADL</ulink> <command>nss_ldap</command> - tool set for this solution. Configure the <filename>/etc/ldap.conf</filename> file so it has - the information needed. The following is an example of a working file: -<screen> -host 192.168.2.1 -base dc=snowshow,dc=com -binddn cn=Manager,dc=snowshow,dc=com -bindpw not24get - -pam_password exop - -nss_base_passwd ou=People,dc=snowshow,dc=com?one -nss_base_shadow ou=People,dc=snowshow,dc=com?one -nss_base_group ou=Groups,dc=snowshow,dc=com?one -ssl no -</screen> - </para> - - <para> - The following procedure may be followed to affect a working configuration: - </para> - <procedure> - <step><para> - Configure the &smb.conf; file as shown above. - </para></step> - - <step><para> - Create the <filename>/etc/krb5.conf</filename> file following the indications above. - </para></step> - - <step><para> - Configure the <filename>/etc/nsswitch.conf</filename> file as shown above. - </para></step> - - <step><para> - Download, build, and install the PADL nss_ldap tool set. Configure the - <filename>/etc/ldap.conf</filename> file as shown above. - </para></step> - - <step><para> - Configure an LDAP server and initialize the directory with the top-level entries needed by IDMAP - as shown in the following LDIF file: -<screen> -dn: dc=snowshow,dc=com -objectClass: dcObject -objectClass: organization -dc: snowshow -o: The Greatest Snow Show in Singapore. -description: Posix and Samba LDAP Identity Database - -dn: cn=Manager,dc=snowshow,dc=com -objectClass: organizationalRole -cn: Manager -description: Directory Manager - -dn: ou=Idmap,dc=snowshow,dc=com -objectClass: organizationalUnit -ou: idmap -</screen> - </para></step> - - <step><para> - Execute the command to join the Samba domain member server to the ADS domain as shown here: -<screen> -&rootprompt; net ads testjoin -Using short domain name -- SNOWSHOW -Joined 'GOODELF' to realm 'SNOWSHOW.COM' -</screen> - </para></step> - - <step><para> - Store the LDAP server access password in the Samba <filename>secrets.tdb</filename> file as follows: -<screen> -&rootprompt; smbpasswd -w not24get -</screen> - </para></step> - - <step><para> - Start the <command>nmbd</command>, <command>winbind</command>, and <command>smbd</command> daemons in the order shown. - </para></step> - </procedure> - - - <para> - <indexterm><primary>diagnostic</primary></indexterm> - Follow the diagnostic procedures shown earlier in this chapter to identify success or failure of the join. - In many cases a failure is indicated by a silent return to the command prompt with no indication of the - reason for failure. - </para> - - </sect3> - - <sect3> - <title>IDMAP and NSS Using LDAP from ADS with RFC2307bis Schema Extension</title> - - <para> - <indexterm><primary>rfc2307bis</primary></indexterm> - <indexterm><primary>schema</primary></indexterm> - The use of this method is messy. The information provided in this section is for guidance only - and is very definitely not complete. This method does work; it is used in a number of large sites - and has an acceptable level of performance. - </para> - - <para> - An example &smb.conf; file is shown in <link linkend="sbewinbindex"/>. - </para> - -<example id="sbewinbindex"> -<title>ADS Membership Using RFC2307bis Identity Resolution &smb.conf; File</title> -<smbconfblock> -<smbconfcomment>Global parameters</smbconfcomment> -<smbconfsection name="[global]"/> -<smbconfoption name="workgroup">BUBBAH</smbconfoption> -<smbconfoption name="netbios name">MADMAX</smbconfoption> -<smbconfoption name="realm">BUBBAH.COM</smbconfoption> -<smbconfoption name="server string">Samba Server</smbconfoption> -<smbconfoption name="security">ADS</smbconfoption> -<smbconfoption name="idmap uid">150000-550000</smbconfoption> -<smbconfoption name="idmap gid">150000-550000</smbconfoption> -<smbconfoption name="template shell">/bin/bash</smbconfoption> -<smbconfoption name="winbind use default domain">Yes</smbconfoption> -<smbconfoption name="winbind trusted domains only">Yes</smbconfoption> -<smbconfoption name="winbind nested groups">Yes</smbconfoption> -</smbconfblock> -</example> - - <para> - <indexterm><primary>nss_ldap</primary></indexterm> - The DMS must be joined to the domain using the usual procedure. Additionally, it is necessary - to build and install the PADL nss_ldap tool set. Be sure to build this tool set with the - following: -<screen> -./configure --enable-rfc2307bis --enable-schema-mapping -make install -</screen> - </para> - - <para> - <indexterm><primary>/etc/nsswitch.conf</primary></indexterm> - The following <filename>/etc/nsswitch.conf</filename> file contents are required: -<screen> -... -passwd: files ldap -shadow: files ldap -group: files ldap -... -hosts: files wins -... -</screen> - </para> - - <para> - <indexterm><primary>/etc/ldap.conf</primary></indexterm> - <indexterm><primary>nss_ldap</primary></indexterm> - The <filename>/etc/ldap.conf</filename> file must be configured also. Refer to the PADL documentation - and source code for nss_ldap instructions. - </para> - - <para> - The next step involves preparation on the ADS schema. This is briefly discussed in the remaining - part of this chapter. - </para> - - <sect4> - <title>IDMAP, Active Directory, and MS Services for UNIX 3.5</title> - - <para> - <indexterm><primary>SFU</primary></indexterm> - The Microsoft Windows Service for UNIX version 3.5 is available for free - <ulink url="http://www.microsoft.com/windows/sfu/">download</ulink> - from the Microsoft Web site. You will need to download this tool and install it following - Microsoft instructions. - </para> - - </sect4> - - <sect4> - <title>IDMAP, Active Directory, and AD4UNIX</title> - - <para> - Instructions for obtaining and installing the AD4UNIX tool set can be found from the - <ulink url="http://www.geekcomix.com/cgi-bin/classnotes/wiki.pl?LDAP01/An_Alternative_Approach"> - Geekcomix</ulink> Web site. - </para> - - </sect4> - - </sect3> - - </sect2> - - <sect2> - <title>UNIX/Linux Client Domain Member</title> - - <para><indexterm> - <primary>user credentials</primary> - </indexterm> - So far this chapter has been mainly concerned with the provision of file and print - services for domain member servers. However, an increasing number of UNIX/Linux - workstations are being installed that do not act as file or print servers to anyone - other than a single desktop user. The key demand for desktop systems is to be able - to log onto any UNIX/Linux or Windows desktop using the same network user credentials. - </para> - - <para><indexterm> - <primary>Single Sign-On</primary> - <see>SSO</see> - </indexterm> - The ability to use a common set of user credential across a variety of network systems - is generally regarded as a single sign-on (SSO) solution. SSO systems are sold by a - large number of vendors and include a range of technologies such as: - </para> - - <itemizedlist> - <listitem><para> - Proxy sign-on - </para></listitem> - - <listitem><para> - Federated directory provisioning - </para></listitem> - - <listitem><para> - Metadirectory server solutions - </para></listitem> - - <listitem><para> - Replacement authentication systems - </para></listitem> - </itemizedlist> - - <para><indexterm> - <primary>Identity management</primary> - </indexterm> - There are really four solutions that provide integrated authentication and - user identity management facilities: - </para> - - <itemizedlist> - <listitem><para> - Samba winbind (free). Samba-3.0.20 introduced a complete replacement for Winbind that now - provides a greater level of scalability in large ADS environments. - </para></listitem> - - <listitem><para> - <ulink url="http://www.padl.com">PADL</ulink> PAM and LDAP tools (free). - </para></listitem> - - <listitem><para> - <ulink url="http://www.vintela.com">Vintela</ulink> Authentication Services (commercial). - </para></listitem> - - <listitem><para> - <ulink url="http://www.centrify.com">Centrify</ulink> DirectControl (commercial). - Centrify's commercial product allows UNIX and Linux systems to use Active Directory - security, directory and policy services. Enhancements include a centralized ID mapping that - allows Samba, DirectControl and Active Directory to seamlessly work together. - </para></listitem> - </itemizedlist> - - <para> - The following guidelines are pertinent to the deployment of winbind-based authentication - and identity resolution with the express purpose of allowing users to log on to UNIX/Linux desktops - using Windows network domain user credentials (username and password). - </para> - - <para> - You should note that it is possible to use LDAP-based PAM and NSS tools to permit distributed - systems logons (SSO), providing user and group accounts are stored in an LDAP directory. This - provides logon services for UNIX/Linux users, while Windows users obtain their sign-on - support via Samba. - </para> - - <para> - <indexterm><primary>Windows Services for UNIX</primary><see>SUS</see></indexterm> - On the other hand, if the authentication and identity resolution backend must be provided by - a Windows NT4-style domain or from an Active Directory Domain that does not have the Microsoft - Windows Services for UNIX installed, winbind is your best friend. Specific guidance for these - situations now follows. - </para> - - <para> - <indexterm><primary>PAM</primary></indexterm> - <indexterm><primary>Identity resolution</primary></indexterm> - <indexterm><primary>NSS</primary></indexterm> - To permit users to log on to a Linux system using Windows network credentials, you need to - configure identity resolution (NSS) and PAM. This means that the basic steps include those - outlined above with the addition of PAM configuration. Given that most workstations (desktop/client) - usually do not need to provide file and print services to a group of users, the configuration - of shares and printers is generally less important. Often this allows the share specifications - to be entirely removed from the &smb.conf; file. That is obviously an administrator decision. - </para> - - <sect3> - <title>NT4 Domain Member</title> - - <para> - The following steps provide a Linux system that users can log onto using - Windows NT4 (or Samba) domain network credentials: - </para> - - <procedure> - <step><para> - Follow the steps outlined in <link linkend="wdcsdm"/> and ensure that - all validation tests function as shown. - </para></step> - - <step><para> - Identify what services users must log on to. On Red Hat Linux, if it is - intended that the user shall be given access to all services, it may be - most expeditious to simply configure the file - <filename>/etc/pam.d/system-auth</filename>. - </para></step> - - <step><para> - Carefully make a backup copy of all PAM configuration files before you - begin making changes. If you break the PAM configuration, please note - that you may need to use an emergency boot process to recover your Linux - system. It is possible to break the ability to log into the system if - PAM files are incorrectly configured. The entire directory - <filename>/etc/pam.d</filename> should be backed up to a safe location. - </para></step> - - <step><para> - If you require only console login support, edit the <filename>/etc/pam.d/login</filename> - so it matches <link linkend="ch9-pamwnbdlogin"/>. - </para></step> - - <step><para> - To provide the ability to log onto the graphical desktop interface, you must edit - the files <filename>gdm</filename> and <filename>xdm</filename> in the - <filename>/etc/pam.d</filename> directory. - </para></step> - - <step><para> - Edit only one file at a time. Carefully validate its operation before attempting - to reboot the machine. - </para></step> - </procedure> - - </sect3> - - <sect3> - <title>ADS Domain Member</title> - - <para> - This procedure should be followed to permit a Linux network client (workstation/desktop) - to permit users to log on using Microsoft Active Directory-based user credentials. - </para> - - <procedure> - <step><para> - Follow the steps outlined in <link linkend="adssdm"/> and ensure that - all validation tests function as shown. - </para></step> - - <step><para> - Identify what services users must log on to. On Red Hat Linux, if it is - intended that the user shall be given access to all services, it may be - most expeditious to simply configure the file - <filename>/etc/pam.d/system-auth</filename> as shown in <link linkend="ch9-rhsysauth"/>. - </para></step> - - <step><para> - Carefully make a backup copy of all PAM configuration files before you - begin making changes. If you break the PAM configuration, please note - that you may need to use an emergency boot process to recover your Linux - system. It is possible to break the ability to log into the system if - PAM files are incorrectly configured. The entire directory - <filename>/etc/pam.d</filename> should be backed up to a safe location. - </para></step> - - <step><para> - If you require only console login support, edit the <filename>/etc/pam.d/login</filename> - so it matches <link linkend="ch9-pamwnbdlogin"/>. - </para></step> - - <step><para> - To provide the ability to log onto the graphical desktop interface, you must edit - the files <filename>gdm</filename> and <filename>xdm</filename> in the - <filename>/etc/pam.d</filename> directory. - </para></step> - - <step><para> - Edit only one file at a time. Carefully validate its operation before attempting - to reboot the machine. - </para></step> - </procedure> - - </sect3> - -<example id="ch9-pamwnbdlogin"> -<title>SUSE: PAM <filename>login</filename> Module Using Winbind</title> -<screen> -# /etc/pam.d/login - -#%PAM-1.0 -auth sufficient pam_unix2.so nullok -auth sufficient pam_winbind.so use_first_pass use_authtok -auth required pam_securetty.so -auth required pam_nologin.so -auth required pam_env.so -auth required pam_mail.so -account sufficient pam_unix2.so -account sufficient pam_winbind.so user_first_pass use_authtok -password required pam_pwcheck.so nullok -password sufficient pam_unix2.so nullok use_first_pass use_authtok -password sufficient pam_winbind.so use_first_pass use_authtok -session sufficient pam_unix2.so none -session sufficient pam_winbind.so use_first_pass use_authtok -session required pam_limits.so -</screen> -</example> - -<example id="ch9-pamwbndxdm"> -<title>SUSE: PAM <filename>xdm</filename> Module Using Winbind</title> -<screen> -# /etc/pam.d/gdm (/etc/pam.d/xdm) - -#%PAM-1.0 -auth sufficient pam_unix2.so nullok -auth sufficient pam_winbind.so use_first_pass use_authtok -account sufficient pam_unix2.so -account sufficient pam_winbind.so use_first_pass use_authtok -password sufficient pam_unix2.so -password sufficient pam_winbind.so use_first_pass use_authtok -session sufficient pam_unix2.so -session sufficient pam_winbind.so use_first_pass use_authtok -session required pam_dev perm.so -session required pam_resmgr.so -</screen> -</example> - -<example id="ch9-rhsysauth"> -<title>Red Hat 9: PAM System Authentication File: <filename>/etc/pam.d/system-auth</filename> Module Using Winbind</title> -<screen> -#%PAM-1.0 -auth required /lib/security/$ISA/pam_env.so -auth sufficient /lib/security/$ISA/pam_unix.so likeauth nullok -auth sufficient /lib/security/$ISA/pam_winbind.so use_first_pass -auth required /lib/security/$ISA/pam_deny.so - -account required /lib/security/$ISA/pam_unix.so -account sufficient /lib/security/$ISA/pam_winbind.so use_first_pass - -password required /lib/security/$ISA/pam_cracklib.so retry=3 type= -# Note: The above line is complete. There is nothing following the '=' -password sufficient /lib/security/$ISA/pam_unix.so \ - nullok use_authtok md5 shadow -password sufficient /lib/security/$ISA/pam_winbind.so use_first_pass -password required /lib/security/$ISA/pam_deny.so - -session required /lib/security/$ISA/pam_limits.so -session sufficient /lib/security/$ISA/pam_unix.so -session sufficient /lib/security/$ISA/pam_winbind.so use_first_pass -</screen> -</example> - - </sect2> - - <sect2> - <title>Key Points Learned</title> - - <para> - The addition of UNIX/Linux Samba servers and clients is a common requirement. In this chapter, you - learned how to integrate such servers so that the UID/GID mappings they use can be consistent - across all domain member servers. You also discovered how to implement the ability to use Samba - or Windows domain account credentials to log on to a UNIX/Linux client. - </para> - - <para> - The following are key points made in this chapter: - </para> - - <itemizedlist> - <listitem><para> - Domain controllers are always authoritative for the domain. - </para></listitem> - - <listitem><para> - Domain members may have local accounts and must be able to resolve the identity of - domain user accounts. Domain user account identity must map to a local UID/GID. That - local UID/GID can be stored in LDAP. This way, it is possible to share the IDMAP data - across all domain member machines. - </para></listitem> - - <listitem><para> - Resolution of user and group identities on domain member machines may be implemented - using direct LDAP services or using winbind. - </para></listitem> - - <listitem><para> - On NSS/PAM enabled UNIX/Linux systems, NSS is responsible for identity management - and PAM is responsible for authentication of logon credentials (username and password). - </para></listitem> - </itemizedlist> - - </sect2> - -</sect1> - -<sect1> - <title>Questions and Answers</title> - - <para> - The following questions were obtained from the mailing list and also from private discussions - with Windows network administrators. - </para> - - <qandaset defaultlabel="chap09qa" type="number"> - <qandaentry> - <question> - - <para> - We use NIS for all UNIX accounts. Why do we need winbind? - </para> - - </question> - <answer> - - <para> - <indexterm><primary>NIS</primary></indexterm> - <indexterm><primary>encrypted passwords</primary></indexterm> - <indexterm><primary>smbpasswd</primary></indexterm> - <indexterm><primary>tdbsam</primary></indexterm> - <indexterm><primary>passdb backend</primary></indexterm> - <indexterm><primary>Winbind</primary></indexterm> - You can use NIS for your UNIX accounts. NIS does not store the Windows encrypted - passwords that need to be stored in one of the acceptable passdb backends. - Your choice of backend is limited to <parameter>smbpasswd</parameter> or - <parameter>tdbsam</parameter>. Winbind is needed to handle the resolution of - SIDs from trusted domains to local UID/GID values. - </para> - - <para> - <indexterm><primary>winbind trusted domains only</primary></indexterm> - <indexterm><primary>getpwnam()</primary></indexterm> - On a domain member server, you effectively map Windows domain users to local users - that are in your NIS database by specifying the <parameter>winbind trusted domains - only</parameter>. This causes user and group account lookups to be routed via - the <command>getpwnam()</command> family of systems calls. On an NIS-enabled client, - this pushes the resolution of users and groups out through NIS. - </para> - - <para> - As a general rule, it is always a good idea to run winbind on all Samba servers. - </para> - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para> - Our IT management people do not like LDAP but are looking at Microsoft Active Directory. - Which is better?<indexterm> - <primary>Active Directory</primary> - </indexterm> - </para> - - </question> - <answer> - - <para><indexterm> - <primary>LDAP</primary> - <secondary>server</secondary> - </indexterm><indexterm> - <primary>Kerberos</primary> - </indexterm><indexterm> - <primary>schema</primary> - </indexterm> - Microsoft Active Directory is an LDAP server that is intricately tied to a Kerberos - infrastructure. Most IT managers who object to LDAP do so because - an LDAP server is most often supplied as a raw tool that needs to be configured and - for which the administrator must create the schema, create the administration tools, and - devise the backup and recovery facilities in a site-dependent manner. LDAP servers - in general are seen as a high-energy, high-risk facility. - </para> - - <para><indexterm> - <primary>management</primary> - </indexterm> - Microsoft Active Directory by comparison is easy to install and configure and - is supplied with all tools necessary to implement and manage the directory. For sites - that lack a lot of technical competence, Active Directory is a good choice. For sites - that have the technical competence to handle Active Directory well, LDAP is a good - alternative. The real issue is, What type of solution does - the site want? If management wants a choice to use an alternative, they may want to - consider the options. On the other hand, if management just wants a solution that works, - Microsoft Active Directory is a good solution. - </para> - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para> - We want to implement a Samba PDC, four Samba BDCs, and 10 Samba servers. Is it possible - to use NIS in place of LDAP? - </para> - - </question> - <answer> - - <para><indexterm> - <primary>NIS</primary> - </indexterm><indexterm> - <primary>LDAP</primary> - </indexterm><indexterm> - <primary>encrypted passwords</primary> - </indexterm><indexterm> - <primary>synchronized</primary> - </indexterm><indexterm> - <primary>secure account password</primary> - </indexterm><indexterm> - <primary>PDC</primary> - </indexterm><indexterm> - <primary>BDC</primary> - </indexterm> - Yes, it is possible to use NIS in place of LDAP, but there may be problems with keeping - the Windows (SMB) encrypted passwords database correctly synchronized across the entire - network. Workstations (Windows client machines) periodically change their domain - membership secure account password. How can you keep changes that are on remote BDCs - synchronized on the PDC? - </para> - - <para><indexterm> - <primary>centralized storage</primary> - </indexterm><indexterm> - <primary>management</primary> - </indexterm><indexterm> - <primary>network Identities</primary> - </indexterm> - LDAP is a more elegant solution because it permits centralized storage and management - of all network identities (user, group, and machine accounts) together with all information - Samba needs to provide to network clients and their users. - </para> - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para> - Are you suggesting that users should not log on to a domain member server? If so, why? - </para> - - </question> - <answer> - - <para><indexterm> - <primary>security</primary> - </indexterm><indexterm> - <primary>data</primary> - <secondary>integrity</secondary> - </indexterm><indexterm> - <primary>mapped drives</primary> - </indexterm> - Many UNIX administrators mock the model that the personal computer industry has adopted - as normative since the early days of Novell NetWare. The old - perception of the necessity to keep users off file and print servers was a result of - fears concerning the security and integrity of data. It was a simple and generally - effective measure to keep users away from servers, except through mapped drives. - </para> - - <para><indexterm> - <primary>user logins</primary> - </indexterm><indexterm> - <primary>risk</primary> - </indexterm><indexterm> - <primary>user errors</primary> - </indexterm><indexterm> - <primary>strategy</primary> - </indexterm><indexterm> - <primary>policy</primary> - </indexterm> - UNIX administrators are fully correct in asserting that UNIX servers and workstations - are identical in terms of the software that is installed. They correctly assert that - in a well-secured environment it is safe to store files on a system that has hundreds - of users. But all network administrators must factor into the decision to allow or - reject general user logins to a UNIX system that is principally a file and print - server the risk to operations through simple user errors. - Only then can one begin to appraise the best strategy and adopt a site-specific - policy that best protects the needs of users and of the organization alike. - </para> - - <para><indexterm> - <primary>system level logins</primary> - </indexterm> - From experience, it is my recommendation to keep general system-level logins to a - practical minimum and to eliminate them if possible. This should not be taken as a - hard rule, though. The better question is, what works best for the site? - </para> - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para><indexterm> - <primary>trusted domains</primary> - </indexterm><indexterm> - <primary>domain</primary> - <secondary>trusted</secondary> - </indexterm><indexterm> - <primary>winbind trusted domains only</primary> - </indexterm><indexterm> - <primary>domain members</primary> - </indexterm> - We want to ensure that only users from our own domain plus from trusted domains can use our - Samba servers. In the &smb.conf; file on all servers, we have enabled the <parameter>winbind - trusted domains only</parameter> parameter. We now find that users from trusted domains - cannot access our servers, and users from Windows clients that are not domain members - can also access our servers. Is this a Samba bug? - </para> - - </question> - <answer> - - <para><indexterm> - <primary>distributed</primary> - </indexterm><indexterm> - <primary>NIS</primary> - </indexterm><indexterm> - <primary>rsync</primary> - </indexterm><indexterm> - <primary>LDAP</primary> - </indexterm><indexterm> - <primary>winbindd</primary> - </indexterm><indexterm> - <primary>/etc/passwd</primary> - </indexterm> - The manual page for this <parameter>winbind trusted domains only</parameter> parameter says, - <quote>This parameter is designed to allow Samba servers that are members of a Samba-controlled - domain to use UNIX accounts distributed vi NIS, rsync, or LDAP as the UIDs for winbindd users - in the hosts primary domain. Therefore, the user <constant>SAMBA\user1</constant> would be - mapped to the account <constant>user1</constant> in <filename>/etc/passwd</filename> instead - of allocating a new UID for him or her.</quote> This clearly suggests that you are trying - to use this parameter inappropriately. - </para> - - <para><indexterm> - <primary>valid users</primary> - </indexterm> - A far better solution is to use the <parameter>valid users</parameter> by specifying - precisely the domain users and groups that should be permitted access to the shares. You could, - for example, set the following parameters: -<screen> -[demoshare] - path = /export/demodata - valid users = @"Domain Users", @"OTHERDOMAIN\Domain Users" -</screen> - </para> - - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para> - What are the benefits of using LDAP for my domain member servers? - </para> - - </question> - <answer> - - <para><indexterm> - <primary>LDAP</primary> - </indexterm><indexterm> - <primary>benefit</primary> - </indexterm><indexterm> - <primary>UID</primary> - </indexterm><indexterm> - <primary>GID</primary> - </indexterm><indexterm> - <primary>Domain Controllers</primary> - </indexterm><indexterm> - <primary>Domain Member servers</primary> - </indexterm><indexterm> - <primary>copy</primary> - </indexterm><indexterm> - <primary>replicate</primary> - </indexterm><indexterm> - <primary>identity</primary> - </indexterm> - The key benefit of using LDAP is that the UID of all users and the GID of all groups - are globally consistent on domain controllers as well as on domain member servers. - This means that it is possible to copy/replicate files across servers without - loss of identity. - </para> - - <para><indexterm> - <primary>Identity resolution</primary> - </indexterm><indexterm> - <primary>winbind</primary> - </indexterm><indexterm> - <primary>IDMAP backend</primary> - </indexterm><indexterm> - <primary>LDAP</primary> - </indexterm><indexterm> - <primary>Domain Controllers</primary> - </indexterm><indexterm> - <primary>Domain Member</primary> - <secondary>servers</secondary> - </indexterm><indexterm> - <primary>Posix</primary> - </indexterm><indexterm> - <primary>account information</primary> - </indexterm> - When use is made of account identity resolution via winbind, even when an IDMAP backend - is stored in LDAP, the UID/GID on domain member servers is consistent, but differs - from the ID that the user/group has on domain controllers. The winbind allocated UID/GID - that is stored in LDAP (or locally) will be in the numeric range specified in the <parameter> - idmap uid/gid</parameter> in the &smb.conf; file. On domain controllers, the UID/GID is - that of the POSIX value assigned in the LDAP directory as part of the POSIX account information. - </para> - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para> - Is proper DNS operation necessary for Samba plus LDAP? If so, what must I put into - my DNS configuration? - </para> - - </question> - <answer> - - <para><indexterm> - <primary>DNS</primary> - <secondary>configuration</secondary> - </indexterm><indexterm> - <primary>DNS</primary> - <secondary>lookup</secondary> - </indexterm><indexterm> - <primary>hosts</primary> - </indexterm><indexterm> - <primary>/etc/nsswitch.conf</primary> - </indexterm><indexterm> - <primary>NSS</primary> - </indexterm><indexterm> - <primary>/etc/hosts</primary> - </indexterm><indexterm> - <primary>WINS</primary> - <secondary>lookup</secondary> - </indexterm> - Samba depends on correctly functioning resolution of hostnames to their IP address. Samba - makes no direct DNS lookup calls, but rather redirects all name-to-address calls via the - <command>getXXXbyXXX()</command> function calls. The configuration of the <constant>hosts</constant> - entry in the NSS <filename>/etc/nsswitch.conf</filename> file determines how the underlying - resolution process is implemented. If the <constant>hosts</constant> entry in your NSS - control file says: -<screen> -hosts: files dns wins -</screen> - this means that a hostname lookup first tries the <filename>/etc/hosts</filename>. - If this fails to resolve, it attempts a DNS lookup, and if that fails, it tries a - WINS lookup. - </para> - - <para><indexterm> - <primary>NetBIOS</primary> - </indexterm><indexterm> - <primary>TCP/IP</primary> - </indexterm><indexterm> - <primary>name resolution</primary> - </indexterm> - The addition of the WINS-based name lookup makes sense only if NetBIOS over TCP/IP has - been enabled on all Windows clients. Where NetBIOS over TCP/IP has been disabled, DNS - is the preferred name resolution technology. This usually makes most sense when Samba - is a client of an Active Directory domain, where NetBIOS use has been disabled. In this - case, the Windows 200x autoregisters all locator records it needs with its own DNS - server or servers. - </para> - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para> - Our Windows 2003 Server Active Directory domain runs with NetBIOS disabled. Can we - use Samba with that configuration? - </para> - - </question> - <answer> - - <para> - Yes. - </para> - - </answer> - </qandaentry> - - <qandaentry> - <question> - - <para><indexterm> - <primary>net</primary> - <secondary>ads</secondary> - <tertiary>join</tertiary> - </indexterm><indexterm> - <primary>net</primary> - <secondary>rpc</secondary> - <tertiary>join</tertiary> - </indexterm> - When I tried to execute net ads join, I got no output. It did not work, so - I think that it failed. I then executed net rpc join and that worked fine. - That is okay, isn't it? - </para> - - </question> - <answer> - - <para><indexterm> - <primary>Kerberos</primary> - </indexterm><indexterm> - <primary>authentication</primary> - </indexterm> - No. This is not okay. It means that your Samba client has joined the ADS domain as - a Windows NT4 client, and Samba will not be using Kerberos-based authentication. - </para> - - </answer> - </qandaentry> - - </qandaset> - -</sect1> - -</chapter> |