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diff --git a/docs/htmldocs/samba-bdc.html b/docs/htmldocs/samba-bdc.html index ef06a89416..95d1cc4e5f 100644 --- a/docs/htmldocs/samba-bdc.html +++ b/docs/htmldocs/samba-bdc.html @@ -1,348 +1,246 @@ -<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> -<HTML -><HEAD -><TITLE ->How to Act as a Backup Domain Controller in a Purely Samba Controlled Domain</TITLE -><META -NAME="GENERATOR" -CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ -"><LINK -REL="HOME" -TITLE="SAMBA Project Documentation" -HREF="samba-howto-collection.html"><LINK -REL="UP" -TITLE="Type of installation" -HREF="type.html"><LINK -REL="PREVIOUS" -TITLE="How to Configure Samba as a NT4 Primary Domain Controller" -HREF="samba-pdc.html"><LINK -REL="NEXT" -TITLE="Samba as a ADS domain member" -HREF="ads.html"></HEAD -><BODY -CLASS="CHAPTER" -BGCOLOR="#FFFFFF" -TEXT="#000000" -LINK="#0000FF" -VLINK="#840084" -ALINK="#0000FF" -><DIV -CLASS="NAVHEADER" -><TABLE -SUMMARY="Header navigation table" -WIDTH="100%" -BORDER="0" -CELLPADDING="0" -CELLSPACING="0" -><TR -><TH -COLSPAN="3" -ALIGN="center" ->SAMBA Project Documentation</TH -></TR -><TR -><TD -WIDTH="10%" -ALIGN="left" -VALIGN="bottom" -><A -HREF="samba-pdc.html" -ACCESSKEY="P" ->Prev</A -></TD -><TD -WIDTH="80%" -ALIGN="center" -VALIGN="bottom" -></TD -><TD -WIDTH="10%" -ALIGN="right" -VALIGN="bottom" -><A -HREF="ads.html" -ACCESSKEY="N" ->Next</A -></TD -></TR -></TABLE -><HR -ALIGN="LEFT" -WIDTH="100%"></DIV -><DIV -CLASS="CHAPTER" -><H1 -><A -NAME="SAMBA-BDC">Chapter 7. How to Act as a Backup Domain Controller in a Purely Samba Controlled Domain</H1 -><DIV -CLASS="SECT1" -><H1 -CLASS="SECT1" -><A -NAME="AEN1127">7.1. Prerequisite Reading</H1 -><P ->Before you continue reading in this chapter, please make sure -that you are comfortable with configuring a Samba PDC -as described in the <A -HREF="Samba-PDC-HOWTO.html" -TARGET="_top" ->Samba-PDC-HOWTO</A ->.</P -></DIV -><DIV -CLASS="SECT1" -><H1 -CLASS="SECT1" -><A -NAME="AEN1131">7.2. Background</H1 -><P ->What is a Domain Controller? It is a machine that is able to answer -logon requests from workstations in a Windows NT Domain. Whenever a -user logs into a Windows NT Workstation, the workstation connects to a -Domain Controller and asks him whether the username and password the -user typed in is correct. The Domain Controller replies with a lot of -information about the user, for example the place where the users -profile is stored, the users full name of the user. All this -information is stored in the NT user database, the so-called SAM.</P -><P ->There are two kinds of Domain Controller in a NT 4 compatible Domain: -A Primary Domain Controller (PDC) and one or more Backup Domain -Controllers (BDC). The PDC contains the master copy of the -SAM. Whenever the SAM has to change, for example when a user changes -his password, this change has to be done on the PDC. A Backup Domain -Controller is a machine that maintains a read-only copy of the -SAM. This way it is able to reply to logon requests and authenticate -users in case the PDC is not available. During this time no changes to -the SAM are possible. Whenever changes to the SAM are done on the PDC, -all BDC receive the changes from the PDC.</P -><P ->Since version 2.2 Samba officially supports domain logons for all -current Windows Clients, including Windows 2000 and XP. This text -assumes the domain to be named SAMBA. To be able to act as a PDC, some -parameters in the [global]-section of the smb.conf have to be set:</P -><P -><PRE -CLASS="PROGRAMLISTING" ->workgroup = SAMBA -domain master = yes -domain logons = yes</PRE -></P -><P ->Several other things like a [homes] and a [netlogon] share also may be -set along with settings for the profile path, the users home drive and -others. This will not be covered in this document.</P -></DIV -><DIV -CLASS="SECT1" -><H1 -CLASS="SECT1" -><A -NAME="AEN1139">7.3. What qualifies a Domain Controller on the network?</H1 -><P ->Every machine that is a Domain Controller for the domain SAMBA has to -register the NetBIOS group name SAMBA#1c with the WINS server and/or -by broadcast on the local network. The PDC also registers the unique -NetBIOS name SAMBA#1b with the WINS server. The name type #1b is -normally reserved for the domain master browser, a role that has -nothing to do with anything related to authentication, but the -Microsoft Domain implementation requires the domain master browser to -be on the same machine as the PDC.</P -><DIV -CLASS="SECT2" -><H2 -CLASS="SECT2" -><A -NAME="AEN1142">7.3.1. How does a Workstation find its domain controller?</H2 -><P ->A NT workstation in the domain SAMBA that wants a local user to be -authenticated has to find the domain controller for SAMBA. It does -this by doing a NetBIOS name query for the group name SAMBA#1c. It -assumes that each of the machines it gets back from the queries is a -domain controller and can answer logon requests. To not open security -holes both the workstation and the selected (TODO: How is the DC -chosen) domain controller authenticate each other. After that the -workstation sends the user's credentials (his name and password) to -the domain controller, asking for approval.</P -></DIV -><DIV -CLASS="SECT2" -><H2 -CLASS="SECT2" -><A -NAME="AEN1145">7.3.2. When is the PDC needed?</H2 -><P ->Whenever a user wants to change his password, this has to be done on -the PDC. To find the PDC, the workstation does a NetBIOS name query -for SAMBA#1b, assuming this machine maintains the master copy of the -SAM. The workstation contacts the PDC, both mutually authenticate and -the password change is done.</P -></DIV -></DIV -><DIV -CLASS="SECT1" -><H1 -CLASS="SECT1" -><A -NAME="AEN1148">7.4. Can Samba be a Backup Domain Controller?</H1 -><P ->With version 2.2, no. The native NT SAM replication protocols have -not yet been fully implemented. The Samba Team is working on -understanding and implementing the protocols, but this work has not -been finished for version 2.2.</P -><P ->Can I get the benefits of a BDC with Samba? Yes. The main reason for -implementing a BDC is availability. If the PDC is a Samba machine, -a second Samba machine can be set up to -service logon requests whenever the PDC is down.</P -></DIV -><DIV -CLASS="SECT1" -><H1 -CLASS="SECT1" -><A -NAME="AEN1152">7.5. How do I set up a Samba BDC?</H1 -><P ->Several things have to be done:</P -><P -></P -><UL -><LI -><P ->The domain SID has to be the same on the PDC and the BDC. This used to -be stored in the file private/MACHINE.SID. This file is not created -anymore since Samba 2.2.5 or even earlier. Nowadays the domain SID is -stored in the file private/secrets.tdb. Simply copying the secrets.tdb -from the PDC to the BDC does not work, as the BDC would -generate a new SID for itself and override the domain SID with this -new BDC SID.</P -><P ->To retrieve the domain SID from the PDC or an existing BDC and store it in the -secrets.tdb, execute 'net rpc getsid' on the BDC.</P -></LI -><LI -><P ->The Unix user database has to be synchronized from the PDC to the -BDC. This means that both the /etc/passwd and /etc/group have to be -replicated from the PDC to the BDC. This can be done manually -whenever changes are made, or the PDC is set up as a NIS master -server and the BDC as a NIS slave server. To set up the BDC as a -mere NIS client would not be enough, as the BDC would not be able to -access its user database in case of a PDC failure.</P -></LI -><LI -><P ->The Samba password database in the file private/smbpasswd has to be -replicated from the PDC to the BDC. This is a bit tricky, see the -next section.</P -></LI -><LI -><P ->Any netlogon share has to be replicated from the PDC to the -BDC. This can be done manually whenever login scripts are changed, -or it can be done automatically together with the smbpasswd -synchronization.</P -></LI -></UL -><P ->Finally, the BDC has to be found by the workstations. This can be done -by setting</P -><P -><PRE -CLASS="PROGRAMLISTING" ->workgroup = samba -domain master = no -domain logons = yes</PRE -></P -><P ->in the [global]-section of the smb.conf of the BDC. This makes the BDC -only register the name SAMBA#1c with the WINS server. This is no -problem as the name SAMBA#1c is a NetBIOS group name that is meant to +<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 6. Backup Domain Control</title><link rel="stylesheet" href="samba.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.60.1"><link rel="home" href="index.html" title="SAMBA Project Documentation"><link rel="up" href="type.html" title="Part II. Server Configuration Basics"><link rel="previous" href="samba-pdc.html" title="Chapter 5. Domain Control"><link rel="next" href="domain-member.html" title="Chapter 7. Domain Membership"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 6. Backup Domain Control</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="samba-pdc.html">Prev</a> </td><th width="60%" align="center">Part II. Server Configuration Basics</th><td width="20%" align="right"> <a accesskey="n" href="domain-member.html">Next</a></td></tr></table><hr></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="samba-bdc"></a>Chapter 6. Backup Domain Control</h2></div><div><div class="author"><h3 class="author"><span class="firstname">John</span> <span class="othername">H.</span> <span class="surname">Terpstra</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><tt class="email"><<a href="mailto:jht@samba.org">jht@samba.org</a>></tt></p></div></div></div></div><div><div class="author"><h3 class="author"><span class="firstname">Volker</span> <span class="surname">Lendecke</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><tt class="email"><<a href="mailto:Volker.Lendecke@SerNet.DE">Volker.Lendecke@SerNet.DE</a>></tt></p></div></div></div></div></div><div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><a href="samba-bdc.html#id2895956">Features And Benefits</a></dt><dt><a href="samba-bdc.html#id2896128">Essential Background Information</a></dt><dd><dl><dt><a href="samba-bdc.html#id2896156">MS Windows NT4 Style Domain Control</a></dt><dt><a href="samba-bdc.html#id2896368">Active Directory Domain Control</a></dt><dt><a href="samba-bdc.html#id2896390">What qualifies a Domain Controller on the network?</a></dt><dt><a href="samba-bdc.html#id2896416">How does a Workstation find its domain controller?</a></dt></dl></dd><dt><a href="samba-bdc.html#id2896462">Backup Domain Controller Configuration</a></dt><dd><dl><dt><a href="samba-bdc.html#id2896532">Example Configuration</a></dt></dl></dd><dt><a href="samba-bdc.html#id2896591">Common Errors</a></dt><dd><dl><dt><a href="samba-bdc.html#id2896605">Machine Accounts keep expiring, what can I do?</a></dt><dt><a href="samba-bdc.html#id2896630">Can Samba be a Backup Domain Controller to an NT4 PDC?</a></dt><dt><a href="samba-bdc.html#id2896663">How do I replicate the smbpasswd file?</a></dt><dt><a href="samba-bdc.html#id2896692">Can I do this all with LDAP?</a></dt></dl></dd></dl></div><p> +Before you continue reading in this section, please make sure that you are comfortable +with configuring a Samba Domain Controller as described in the +<a href="Samba-PDC-HOWTO.html" target="_top">Domain Control Chapter</a>. +</p><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2895956"></a>Features And Benefits</h2></div></div><div></div></div><p> +This is one of the most difficult chapters to summarise. It matters not what we say here +for someone will still draw conclusions and / or approach the Samba-Team with expectations +that are either not yet capable of being delivered, or that can be achieved for more +effectively using a totally different approach. Since this HOWTO is already so large and +extensive, we have taken the decision to provide sufficient (but not comprehensive) +information regarding Backup Domain Control. In the event that you should have a persistent +concern that is not addressed in this HOWTO document then please email +<a href="mailto:jht@samba.org" target="_top">John H Terpstra</a> clearly setting out your requirements +and / or question and we will do our best to provide a solution. +</p><p> +Samba-3 is capable of acting as a Backup Domain Controller to another Samba Primary Domain +Controller. A Samba-3 PDC can operate with an LDAP Account backend. The Samba-3 BDC can +operate with a slave LDAP server for the Account backend. This effectively gives samba a high +degree of scalability. This is a very sweet (nice) solution for large organisations. +</p><p> +While it is possible to run a Samba-3 BDC with non-LDAP backend, the administrator will +need to figure out precisely what is the best way to replicate (copy / distribute) the +user and machine Accounts backend. +</p><p> +The use of a non-LDAP backend SAM database is particularly problematic because Domain member +servers and workstations periodically change the machine trust account password. The new +password is then stored only locally. This means that in the absence of a centrally stored +accounts database (such as that provided with an LDAP based solution) if Samba-3 is running +as a BDC, the PDC instance of the Domain member trust account password will not reach the +PDC (master) copy of the SAM. If the PDC SAM is then replicated to BDCs this results in +overwriting of the SAM that contains the updated (changed) trust account password with resulting +breakage of the domain trust. +</p><p> +Considering the number of comments and questions raised concerning how to configure a BDC +lets consider each possible option and look at the pro's and con's for each theoretical solution: +</p><div class="itemizedlist"><p class="title"><b>Backup Domain Backend Account Distribution Options</b></p><ul type="disc"><li><p> + Solution: Passwd Backend is LDAP based, BDCs use a slave LDAP server + </p><p> + Arguments For: This is a neat and manageable solution. The LDAP based SAM (ldapsam) + is constantly kept up to date. + </p><p> + Arguments Against: Complexity + </p></li><li><p> + Passdb Backend is tdbsam based, BDCs use cron based "net rcp vampire" to + suck down the Accounts database from the PDC + </p><p> + Arguments For: It would be a nice solution + </p><p> + Arguments Against: It does not work because Samba-3 does not support the required + protocols. This may become a later feature but is not available today. + </p></li><li><p> + Make use of rsync to replicate (pull down) copies of the essential account files + </p><p> + Arguments For: It is a simple solution, easy to set up as a scheduled job + </p><p> + Arguments Against: This will over-write the locally changed machine trust account + passwords. This is a broken and flawed solution. Do NOT do this. + </p></li><li><p> + Operate with an entirely local accounts database (not recommended) + </p><p> + Arguments For: Simple, easy to maintain + </p><p> + Arguments Against: All machine trust accounts and user accounts will be locally + maintained. Domain users will NOT be able to roam from office to office. This is + a broken and flawed solution. Do NOT do this. + </p></li></ul></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2896128"></a>Essential Background Information</h2></div></div><div></div></div><p> +A Domain Controller is a machine that is able to answer logon requests from network +workstations. Microsoft LanManager and IBM LanServer were two early products that +provided this capability. The technology has become known as the LanMan Netlogon service. +</p><p> +When MS Windows NT3.10 was first released it supported an new style of Domain Control +and with it a new form of the network logon service that has extended functionality. +This service became known as the NT NetLogon Service. The nature of this service has +changed with the evolution of MS Windows NT and today provides a very complex array of +services that are implemented over a complex spectrum of technologies. +</p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896156"></a>MS Windows NT4 Style Domain Control</h3></div></div><div></div></div><p> +Whenever a user logs into a Windows NT4 / 200x / XP Profresional Workstation, +the workstation connects to a Domain Controller (authentication server) to validate +the username and password that the user entered are valid. If the information entered +does not validate against the account information that has been stored in the Domain +Control database (the SAM, or Security Accounts Manager database) then a set of error +codes is returned to the workstation that has made the authentication request. +</p><p> +When the username / password pair has been validated, the Domain Controller +(authentication server) will respond with full enumeration of the account information +that has been stored regarding that user in the User and Machine Accounts database +for that Domain. This information contains a complete network access profile for +the user but excludes any information that is particular to the user's desktop profile, +or for that matter it excludes all desktop profiles for groups that the user may +belong to. It does include password time limits, password uniqueness controls, +network access time limits, account validity information, machine names from which the +user may access the network, and much more. All this information was stored in the SAM +in all versions of MS Windows NT (3.10, 3.50, 3.51, 4.0). +</p><p> +The account information (user and machine) on Domain Controllers is stored in two files, +one containing the Security information and the other the SAM. These are stored in files +by the same name in the <tt class="filename">C:\WinNT\System32\config</tt> directory. These +are the files that are involved in replication of the SAM database where Backup Domain +Controllers are present on the network. +</p><p> +There are two situations in which it is desirable to install Backup Domain Controllers: +</p><div class="itemizedlist"><ul type="disc"><li><p> + On the local network that the Primary Domain Controller is on if there are many + workstations and/or where the PDC is generally very busy. In this case the BDCs + will pick up network logon requests and help to add robustness to network services. + </p></li><li><p> + At each remote site, to reduce wide area network traffic and to add stability to + remote network operations. The design of the network, the strategic placement of + Backup Domain Controllers, together with an implementation that localises as much + of network to client interchange as possible will help to minimise wide area network + bandwidth needs (and thus costs). + </p></li></ul></div><p> +The PDC contains the master copy of the SAM. In the event that an administrator makes a +change to the user account database while physically present on the local network that +has the PDC, the change will likely be made directly to the PDC instance of the master +copy of the SAM. In the event that this update may be performed in a branch office the +change will likely be stored in a delta file on the local BDC. The BDC will then send +a trigger to the PDC to commence the process of SAM synchronisation. The PDC will then +request the delta from the BDC and apply it to the master SAM. THe PDC will then contact +all the BDCs in the Domain and trigger them to obtain the update and then apply that to +their own copy of the SAM. +</p><p> +Thus the BDC is said to hold a <span class="emphasis"><em>read-only</em></span> of the SAM from which +it is able to process network logon requests and to authenticate users. The BDC can +continue to provide this service, particularly while, for example, the wide area +network link to the PDC is down. Thus a BDC plays a very important role in both +maintenance of Domain security as well as in network integrity. +</p><p> +In the event that the PDC should need to be taken out of service, or if it dies, then +one of the BDCs can be promoted to a PDC. If this happens while the original PDC is on +line then it is automatically demoted to a BDC. This is an important aspect of Domain +Controller management. The tool that is used to affect a promotion or a demotion is the +Server Manager for Domains. +</p><div class="sect3" lang="en"><div class="titlepage"><div><div><h4 class="title"><a name="id2896305"></a>Example PDC Configuration</h4></div></div><div></div></div><p> +Since version 2.2 Samba officially supports domain logons for all current Windows Clients, +including Windows NT4, 2003 and XP Professional. For samba to be enabled as a PDC some +parameters in the <i class="parameter"><tt>[global]</tt></i>-section of the <tt class="filename">smb.conf</tt> have to be set: +</p><pre class="programlisting"> + workgroup = SAMBA + domain master = yes + domain logons = yes +</pre><p> +Several other things like a <i class="parameter"><tt>[homes]</tt></i> and a <i class="parameter"><tt>[netlogon]</tt></i> share also need to be set along with +settings for the profile path, the users home drive, etc.. This will not be covered in this +chapter, for more information please refer to the chapter on Domain Control. +</p></div></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896368"></a>Active Directory Domain Control</h3></div></div><div></div></div><p> +As of the release of MS Windows 2000 and Active Directory, this information is now stored +in a directory that can be replicated and for which partial or full administrative control +can be delegated. Samba-3 is NOT able to be a Domain Controller within an Active Directory +tree, and it can not be an Active Directory server. This means that Samba-3 also can NOT +act as a Backup Domain Contoller to an Active Directory Domain Controller. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896390"></a>What qualifies a Domain Controller on the network?</h3></div></div><div></div></div><p> +Every machine that is a Domain Controller for the domain SAMBA has to register the NetBIOS +group name SAMBA<#1c> with the WINS server and/or by broadcast on the local network. +The PDC also registers the unique NetBIOS name SAMBA<#1b> with the WINS server. +The name type <#1b> name is normally reserved for the Domain Master Browser, a role +that has nothing to do with anything related to authentication, but the Microsoft Domain +implementation requires the domain master browser to be on the same machine as the PDC. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896416"></a>How does a Workstation find its domain controller?</h3></div></div><div></div></div><p> +An MS Windows NT4 / 200x / XP Professional workstation in the domain SAMBA that wants a +local user to be authenticated has to find the domain controller for SAMBA. It does this +by doing a NetBIOS name query for the group name SAMBA<#1c>. It assumes that each +of the machines it gets back from the queries is a domain controller and can answer logon +requests. To not open security holes both the workstation and the selected domain controller +authenticate each other. After that the workstation sends the user's credentials (name and +password) to the local Domain Controller, for valdation. +</p></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2896462"></a>Backup Domain Controller Configuration</h2></div></div><div></div></div><p> +Several things have to be done: +</p><div class="itemizedlist"><ul type="disc"><li><p> + The domain SID has to be the same on the PDC and the BDC. This used to + be stored in the file private/MACHINE.SID. This file is not created + anymore since Samba 2.2.5 or even earlier. Nowadays the domain SID is + stored in the file private/secrets.tdb. Simply copying the secrets.tdb + from the PDC to the BDC does not work, as the BDC would + generate a new SID for itself and override the domain SID with this + new BDC SID.</p><p> + To retrieve the domain SID from the PDC or an existing BDC and store it in the + secrets.tdb, execute 'net rpc getsid' on the BDC. + </p></li><li><p> + The Unix user database has to be synchronized from the PDC to the + BDC. This means that both the /etc/passwd and /etc/group have to be + replicated from the PDC to the BDC. This can be done manually + whenever changes are made, or the PDC is set up as a NIS master + server and the BDC as a NIS slave server. To set up the BDC as a + mere NIS client would not be enough, as the BDC would not be able to + access its user database in case of a PDC failure. + </p></li><li><p> + The Samba password database in the file private/smbpasswd has to be + replicated from the PDC to the BDC. This is a bit tricky, see the + next section. + </p></li><li><p> + Any netlogon share has to be replicated from the PDC to the + BDC. This can be done manually whenever login scripts are changed, + or it can be done automatically together with the smbpasswd + synchronization. + </p></li></ul></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896532"></a>Example Configuration</h3></div></div><div></div></div><p> +Finally, the BDC has to be found by the workstations. This can be done by setting: +</p><pre class="programlisting"> + workgroup = SAMBA + domain master = no + domain logons = yes +</pre><p> +in the <i class="parameter"><tt>[global]</tt></i>-section of the <tt class="filename">smb.conf</tt> of the BDC. This makes the BDC +only register the name SAMBA<#1c> with the WINS server. This is no +problem as the name SAMBA<#1c> is a NetBIOS group name that is meant to be registered by more than one machine. The parameter 'domain master = -no' forces the BDC not to register SAMBA#1b which as a unique NetBIOS -name is reserved for the Primary Domain Controller.</P -><DIV -CLASS="SECT2" -><H2 -CLASS="SECT2" -><A -NAME="AEN1169">7.5.1. How do I replicate the smbpasswd file?</H2 -><P ->Replication of the smbpasswd file is sensitive. It has to be done -whenever changes to the SAM are made. Every user's password change is -done in the smbpasswd file and has to be replicated to the BDC. So -replicating the smbpasswd file very often is necessary.</P -><P ->As the smbpasswd file contains plain text password equivalents, it -must not be sent unencrypted over the wire. The best way to set up -smbpasswd replication from the PDC to the BDC is to use the utility -rsync. rsync can use ssh as a transport. ssh itself can be set up to -accept *only* rsync transfer without requiring the user to type a -password.</P -></DIV -></DIV -></DIV -><DIV -CLASS="NAVFOOTER" -><HR -ALIGN="LEFT" -WIDTH="100%"><TABLE -SUMMARY="Footer navigation table" -WIDTH="100%" -BORDER="0" -CELLPADDING="0" -CELLSPACING="0" -><TR -><TD -WIDTH="33%" -ALIGN="left" -VALIGN="top" -><A -HREF="samba-pdc.html" -ACCESSKEY="P" ->Prev</A -></TD -><TD -WIDTH="34%" -ALIGN="center" -VALIGN="top" -><A -HREF="samba-howto-collection.html" -ACCESSKEY="H" ->Home</A -></TD -><TD -WIDTH="33%" -ALIGN="right" -VALIGN="top" -><A -HREF="ads.html" -ACCESSKEY="N" ->Next</A -></TD -></TR -><TR -><TD -WIDTH="33%" -ALIGN="left" -VALIGN="top" ->How to Configure Samba as a NT4 Primary Domain Controller</TD -><TD -WIDTH="34%" -ALIGN="center" -VALIGN="top" -><A -HREF="type.html" -ACCESSKEY="U" ->Up</A -></TD -><TD -WIDTH="33%" -ALIGN="right" -VALIGN="top" ->Samba as a ADS domain member</TD -></TR -></TABLE -></DIV -></BODY -></HTML ->
\ No newline at end of file +no' forces the BDC not to register SAMBA<#1b> which as a unique NetBIOS +name is reserved for the Primary Domain Controller. +</p></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2896591"></a>Common Errors</h2></div></div><div></div></div><p> +As this is a rather new area for Samba there are not many examples that we may refer to. Keep +watching for updates to this section. +</p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896605"></a>Machine Accounts keep expiring, what can I do?</h3></div></div><div></div></div><p> +This problem will occur when occur when the passdb (SAM) files are copied from a central +server but the local Backup Domain Controllers. Local machine trust account password updates +are not copied back to the central server. The newer machine account password is then over +written when the SAM is copied from the PDC. The result is that the Domain member machine +on start up will find that it's passwords does not match the one now in the database and +since the startup security check will now fail, this machine will not allow logon attempts +to procede and the account expiry error will be reported. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896630"></a>Can Samba be a Backup Domain Controller to an NT4 PDC?</h3></div></div><div></div></div><p> +With version 2.2, no. The native NT4 SAM replication protocols have not yet been fully +implemented. The Samba Team is working on understanding and implementing the protocols, +but this work has not been finished for version 2.2. +</p><p> +With version 3.0, the work on both the replication protocols and a suitable storage +mechanism has progressed, and some form of NT4 BDC support is expected soon. +</p><p> +Can I get the benefits of a BDC with Samba? Yes. The main reason for implementing a +BDC is availability. If the PDC is a Samba machine, a second Samba machine can be set up to +service logon requests whenever the PDC is down. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896663"></a>How do I replicate the smbpasswd file?</h3></div></div><div></div></div><p> +Replication of the smbpasswd file is sensitive. It has to be done whenever changes +to the SAM are made. Every user's password change is done in the smbpasswd file and +has to be replicated to the BDC. So replicating the smbpasswd file very often is necessary. +</p><p> +As the smbpasswd file contains plain text password equivalents, it must not be +sent unencrypted over the wire. The best way to set up smbpasswd replication from +the PDC to the BDC is to use the utility rsync. rsync can use ssh as a transport. +Ssh itself can be set up to accept *only* rsync transfer without requiring the user +to type a password. +</p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2896692"></a>Can I do this all with LDAP?</h3></div></div><div></div></div><p> +The simple answer is YES. Samba's pdb_ldap code supports binding to a replica +LDAP server, and will also follow referrals and rebind to the master if it ever +needs to make a modification to the database. (Normally BDCs are read only, so +this will not occur often). +</p></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="samba-pdc.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="type.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="domain-member.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 5. Domain Control </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Chapter 7. Domain Membership</td></tr></table></div></body></html> |