path: root/docs/guide/Chap08-MigrateNT4Samba3.xml

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<chapter id="migration">
  <title>Migrating NT4 Domain to Samba-3</title>

	<para>
	Ever since Microsoft announced that they are discontinuing support for Windows
	NT4, Samba users started to ask for detailed instructions for how to migrate
	from NT4 to Samba-3. This chapter provides background information that should
	meet these needs.
	</para>

	<para>
	One wonders how many NT4 systems will be left in service by the time you read this
	book though.
	</para>

<sect1>
	<title>Introduction</title>

      <para><indexterm>
	  <primary>migration</primary>
	</indexterm>
	Network administrators who want to migrate off a Windows NT4 environment know
	one thing with certainty. They feel that NT4 has been abandoned and they want
	to update. The desire to get off NT4 and to not adopt Windows 200x and Active
	Directory is driven by a mixture of concerns over complexity, cost, fear of
	failure, and much more.
	</para>

      <para><indexterm>
	  <primary>group policies</primary>
	</indexterm><indexterm>
	  <primary>accounts</primary>
	  <secondary>user</secondary>
	</indexterm><indexterm>
	  <primary>accounts</primary>
	  <secondary>group</secondary>
	</indexterm><indexterm>
	  <primary>accounts</primary>
	  <secondary>machine</secondary>
	</indexterm>
	The migration from NT4 to Samba-3 can involve a number of factors, including:
	migration of data to another server, migration of network environment controls
	such as group policies, and finally migration of the users, groups, and machine
	accounts.
	</para>

      <para><indexterm>
	  <primary>accounts</primary>
	  <secondary>Domain</secondary>
	</indexterm>
	It should be pointed out now that it is possible to migrate some systems from
	Windows NT4 Domain environments to a Samba-3 Domain Environment. This is certainly
	not possible in every case. It is possible to just migrate the Domain accounts
	to Samba-3 and then to switch machines, but as a hands-off transition, this is more
	an exception than the rule. Most systems require some tweaking and adjusting
	following migration before an environment that is acceptable for immediate use
	is obtained.
	</para>

	<sect2>
		<title>Assignment Tasks</title>

	<para><indexterm>
	    <primary>LDAP</primary>
	  </indexterm><indexterm>
	    <primary>ldapsam</primary>
	  </indexterm><indexterm>
	    <primary>passdb backend</primary>
	  </indexterm>
		You are about to migrate an MS Windows NT4 Domain accounts database to
		a Samba-3 server. The Samba-3 server is using a 
		<parameter>passdb backend</parameter> based on LDAP. The 
		<constant>ldapsam</constant> is ideal because an LDAP backend can be distributed
		for use with BDCs &smbmdash; generally essential for larger networks.
		</para>

		<para>
		Your objective is to document the process of migrating user and group accounts
		from several NT4 Domains into a single Samba-3 LDAP backend database.
		</para>

	</sect2>
</sect1>

<sect1>
	<title>Dissection and Discussion</title>

      <para><indexterm>
	  <primary>snap-shot</primary>
	</indexterm><indexterm>
	  <primary>NT4 registry</primary>
	</indexterm><indexterm>
	  <primary>registry</primary>
	  <secondary>keys</secondary>
	  <tertiary>SAM</tertiary>
	</indexterm><indexterm>
	  <primary>registry</primary>
	  <secondary>keys</secondary>
	  <tertiary>SECURITY</tertiary>
	</indexterm><indexterm>
	  <primary>SAM</primary>
	</indexterm><indexterm>
	  <primary>Security Account Manager</primary>
	  <see>SAM</see>
	</indexterm>
	The migration process takes a snap-shot of information that is stored in the
	Windows NT4 registry based accounts database. That information resides in
	the Security Account Manager (SAM) portion of the NT4 Registry under keys called
	<constant>SAM</constant> and <constant>SECURITY</constant>.
	</para>

      <warning><para><indexterm>
	    <primary>crippled</primary>
	  </indexterm><indexterm>
	    <primary>inoperative</primary>
	  </indexterm>
	The Windows NT4 registry keys called <constant>SAM</constant> and <constant>SECURITY</constant>
	are protected so that you cannot view the contents. If you change the security setting
	to reveal the contents under these hive keys, your Windows NT4 Domain is crippled. Do not
	do this unless you are willing to render your domain controller inoperative.
	</para></warning>

      <para><indexterm>
	  <primary>migration</primary>
	  <secondary>objectives</secondary>
	</indexterm><indexterm>
	  <primary>disruptive</primary>
	</indexterm>
	Before commencing an NT4 to Samba-3 migration, you should consider what your objectives are.
	While in some cases it is possible simply to migrate an NT4 domain to a single Samba-3 server,
	that may not be a good idea from an administration perspective. Since you are going through a
	certain amount of disruptive activity anyhow, why not take this as an opportunity to review
	the structure of the network, how Windows clients are controlled and how they
	interact with the network environment.
	</para>

      <para><indexterm>
	  <primary>network</primary>
	  <secondary>logon scripts</secondary>
	</indexterm><indexterm>
	  <primary>profiles share</primary>
	</indexterm><indexterm>
	  <primary>security descriptors</primary>
	</indexterm>
	MS Windows NT4 was introduced some time around 1996. Many environments in which NT4 was deployed
	have done little to keep the NT4 server environment up-to-date with more recent Windows releases, 
	particularly Windows XP Professional. The migration provides opportunity to revise and update 
	roaming profile deployment as well as folder redirection. Given that you must port the 
	greater network configuration of this from the old NT4 server to the new Samba-3 server, you
	also must validate the security descriptors in the profiles share as well as network logon
	scripts. Feedback from sites that are migrating to Samba-3 suggests that many are using this
	as a good time to update desktop systems also. In all, the extra effort should constitute no
	real disruption to users, rather with due diligence and care should make their network experience
	a much happier one.
	</para>

	<sect2>
		<title>Technical Issues</title>

	<para><indexterm>
	    <primary>strategic</primary>
	  </indexterm>
		Migration of an NT4 Domain user and group database to Samba-3 involves a certain strategic
		element. Many sites have asked for instructions regarding merging of multiple different NT4
		Domains into one Samba-3 LDAP database. It would appear that this is viewed as a significant
		added value compared with the alternative of migration to Windows Server 200x and Active
		Directory. The diagram in <link linkend="ch8-migration"/> illustrates the effect of migration
		from a Windows NT4 Domain to a Samba Domain.
		</para>

		<figure id="ch8-migration">
			<title>Schematic Explaining the <command>net rpc vampire</command> Process</title>
			<mediaobject>
				<imageobject role="latex">
					<imagedata fileref="guide/images/ch8-migration.png" scale="80" scalefit="1"/>
				</imageobject>
				<imageobject>
					<imagedata fileref="guide/images/ch8-migration.png" scale="80" scalefit="1"/>
				</imageobject>
			</mediaobject>
		</figure>

		<para>
		In any case, the migration process involves the following steps:
		</para>

		<itemizedlist>
			<listitem><para>
			Prepare the target Samba-3 server. This involves configuring Samba-3 for
			migration to either a tdbsam or an ldapsam backend.
			</para></listitem>

	  <listitem><para><indexterm>
		<primary>uppercase</primary>
	      </indexterm><indexterm>
		<primary>Posix</primary>
	      </indexterm><indexterm>
		<primary>lower-case</primary>
	      </indexterm>
			Clean up the source NT4 PDC. Delete all accounts that need not be migrated.
			Delete all files that should not be migrated. Where possible, change NT Group
			names so there are no spaces or uppercase characters. This is important if
			the target UNIX host insists on Posix compliant all lower-case user and group
			names.
			</para></listitem>

			<listitem><para>
			Step through the migration process.
			</para></listitem>

	  <listitem><para><indexterm>
		<primary>PDC</primary>
	      </indexterm>
			Remove the NT4 PDC from the network.
			</para></listitem>

			<listitem><para>
			Upgrade the Samba-3 server from a BDC to a PDC, and validate all account
			information.
			</para></listitem>
		</itemizedlist>

	<para><indexterm>
	    <primary>merge</primary>
	  </indexterm><indexterm>
	    <primary>passdb.tdb</primary>
	  </indexterm>
		If you are wanting to merge multiple NT4 Domain account databases into one Samba Domain,
		you must now dump the contents of the first migration and edit it as appropriate. Now clean
		out (remove) the tdbsam backend file (<filename>passdb.tdb</filename>), or the LDAP database
		files. You must start each migration with a new database into which you merge your NT4 
		domains.
		</para>

	<para><indexterm>
	    <primary>dump</primary>
	  </indexterm>
		At this point, you are ready to perform the second migration following the same steps as
		for the first. In other words, dump the database, edit it, and then you may merge the
		dump for the first and second migrations.
		</para>

	<para><indexterm>
	    <primary>LDAP</primary>
	  </indexterm><indexterm>
	    <primary>migrate</primary>
	  </indexterm><indexterm>
	    <primary>Domain SID</primary>
	  </indexterm>
		You must be careful. If you choose to migrate to an LDAP backend, your dump file
		now contains the full account information, including the Domain SID. The Domain SID for each 
		of the two NT4 Domains will be different. You must choose one, and change the Domain 
		portion of the account SIDs so that all are the same.
		</para>

	<para><indexterm>
	    <primary>passdb.tdb</primary>
	  </indexterm><indexterm>
	    <primary>/etc/passwd</primary>
	  </indexterm><indexterm>
	    <primary>merged</primary>
	  </indexterm><indexterm>
	    <primary>logon script</primary>
	  </indexterm><indexterm>
	    <primary>logon hours</primary>
	  </indexterm><indexterm>
	    <primary>logon machines</primary>
	  </indexterm><indexterm>
	    <primary>profile path</primary>
	  </indexterm><indexterm>
	    <primary>smbpasswd</primary>
	  </indexterm><indexterm>
	    <primary>tdbsam</primary>
	  </indexterm><indexterm>
	    <primary>LDAP backend</primary>
	  </indexterm><indexterm>
	    <primary>export</primary>
	  </indexterm><indexterm>
	    <primary>import</primary>
	  </indexterm>
		If you choose to use a tdbsam (<filename>passdb.tdb</filename>) backend file, your best choice
		is to use <command>pdbedit</command> to export the contents of the tdbsam file into an
		smbpasswd data file. This automatically strips out all Domain specific information,
		such as logon hours, logon machines, logon script, profile path, as well as the Domain SID.
		The resulting file can be easily merged with other migration attempts (each of which must start
		with a clean file). It should also be noted that all users that end up in the merged smbpasswd
		file must have an account in <filename>/etc/passwd</filename>. The resulting smbpasswd file
		may be exported/imported into either a tdbsam (<filename>passdb.tdb</filename>), or else into
		an LDAP backend.
		</para>

	<figure id="NT4DUM">
		<title>View of Accounts in NT4 Domain User Manager</title>
		<mediaobject>
			<imageobject role="latex">
				<imagedata fileref="guide/images/UserMgrNT4.png" scale="50" scalefit="1"/>
			</imageobject>
			<imageobject>
				<imagedata fileref="guide/images/UserMgrNT4.png" scale="50" scalefit="1"/>
			</imageobject>
		</mediaobject>
	</figure>

	</sect2>


	<sect2>
		<title>Political Issues</title>

		<para>
		The merging of multiple Windows NT4 style Domains into a single LDAP-backend-based Samba-3
		Domain may be seen by those who had power over them as a loss of prestige or a loss of
		power. The imposition of a single Domain may even be seen as a threat. So in migrating and
		merging account databases, be consciously aware of the political fall-out in which you
		may find yourself entangled when key staff feel a loss of prestige.
		</para>

		<para>
		The best advice that can be given to those who set out to merge NT4 Domains into one single
		Samba-3 Domain is to promote (sell) the action as one that reduces costs and delivers
		greater network interoperability and manageability.
		</para>

	</sect2>

</sect1>

<sect1>
	<title>Implementation</title>

	<para>
	You can present here the steps and example output for two NT4 to Samba-3 Domain migrations. The
	first uses an LDAP-based backend, and the second uses a tdbsam backend. In each case the
	scripts you specify in the &smb.conf; file for the <parameter>add user script</parameter>
	collection of parameters are used to effect the addition of accounts into the passdb backend.
	</para>

	<sect2>
	<title>NT4 Migration Using LDAP Backend</title>

	<para>
	In this instance, you migrate an NT4 PDC to an LDAP backend. The accounts you are about
	to migrate are shown in <link linkend="NT4DUM"/>. In this example you make use of the
	smbldap-tools scripts to add the accounts that are migrated into the ldapsam passdb backend.
	Four scripts are essential to the migration process. There are other scripts that will be required
	for daily management, but these are not critical to migration. The critical scripts are dependant
	on which passdb backend is being used. Refer to <link linkend="ch8-vampire"/> to see which scripts
	must be provided so that the migration process can complete.
	</para>

	<para>
	Do verify that you have correctly specified in the &smb.conf; file the scripts, and arguments 
	that should be passed to them, before attempting to perform the account migration.
	</para>

	<table id="ch8-vampire">
		<title>Samba &smb.conf; Scripts Essential to Migration</title>
		<tgroup cols="3">
			<colspec align="left"/>
			<colspec align="center"/>
			<colspec align="center"/>
			<thead>
				<row>
					<entry>Entity</entry>
					<entry>ldapsam Script</entry>
					<entry>tdbsam Script</entry>
				</row>
			</thead>
			<tbody>
				<row>
					<entry>Add User Accounts</entry>
					<entry>smbldap-useradd.pl</entry>
					<entry>useradd</entry>
				</row>
				<row>
					<entry>Delete User Accounts</entry>
					<entry>smbldap-userdel.pl</entry>
					<entry>userdel</entry>
				</row>
				<row>
					<entry>Add Group Accounts</entry>
					<entry>smbldap-groupadd.pl</entry>
					<entry>groupadd</entry>
				</row>
				<row>
					<entry>Delete Group Accounts</entry>
					<entry>smbldap-groupdel.pl</entry>
					<entry>groupdel</entry>
				</row>
				<row>
					<entry>Add User to Group</entry>
					<entry>smbldap-groupmod.pl</entry>
					<entry>usermod (See Note)</entry>
				</row>
				<row>
					<entry>Add Machine Accounts</entry>
					<entry>smbldap-useradd.pl</entry>
					<entry>useradd</entry>
				</row>
			</tbody>
		</tgroup>
	</table>

	<note><para>
	The UNIX/Linux <command>usermod</command> utility does not permit simple user addition to (or deletion
	of users from) groups. This is a feature provided by the smbldap-tools scripts. If you want this
	capability you will need to create your own tool to do this. Alternately, you can search the web
	to locate a utility called <command>groupmem</command> (by George Kraft) that provides this functionality.
	The <command>groupmem</command> utility was contributed to the shadow package but has not surfaced
	in the formal commands provided by Linux distributions (March 2004).
	</para></note>

	<para>
	Before starting the migration, all dead accounts were removed using the User Manager for Domains.
	</para>

	<procedure>
		<step><para>
		Install and configure the Samba-3 server precisely as shown in Chapter 6 for the server
		called <constant>MASSIVE</constant>. The Domain name <constant>MEGANET</constant> must
		match that of the NT4 Domain from which you are about to migrate. Do not execute any Samba
		executables.
		</para></step>

	  <step><para><indexterm>
		<primary>domain master</primary>
	      </indexterm><indexterm>
		<primary>BDC</primary>
	      </indexterm>
		Edit the &smb.conf; file to temporarily change the parameter 
		<smbconfoption><name>domain master</name><value>No</value></smbconfoption> so
		the Samba server functions as a BDC for the purpose of migration.
                </para></step>

	  <step><para><indexterm>
		<primary>preload.LDIF</primary>
	      </indexterm>
		Create a file called <filename>preload.LDIF</filename> as shown in <link linkend="ch8-LDIF"/>.
		</para></step>

	  <step><para><indexterm>
		<primary>slapadd</primary>
	      </indexterm>
		Preload the LDAP database so it is ready to receive the information from the NT4 PDC.
		This pre-loads the LDAP directory with the top-level information, as well as the
		top level containers for user, group, computer, and domain account data. Execute the
		instruction shown here:
<screen>
&rootprompt; slapadd -v -l preload.LDIF
added: "dc=abmas,dc=biz" (00000001)
added: "cn=Manager,dc=abmas,dc=biz" (00000002)
added: "ou=People,dc=abmas,dc=biz" (00000003)
added: "ou=Computers,dc=abmas,dc=biz" (00000004)
added: "ou=Groups,dc=abmas,dc=biz" (00000005)
added: "ou=Idmap,dc=abmas,dc=biz" (00000006)
added: "ou=Domains,dc=abmas,dc=biz" (00000007)
</screen>
		</para></step>

		<step><para>
		Start the LDAP server.
		</para></step>

	  <step><para><indexterm>
		<primary>ping</primary>
	      </indexterm>
		Verify that the NT4 PDC can be reached:
<screen>
&rootprompt; ping nt4s
PING nt4s.abmas.biz (192.168.2.250) 56(84) bytes of data.
64 bytes from NT4S (192.168.2.250): icmp_seq=1 ttl=128 time=10.2 ms
64 bytes from NT4S (192.168.2.250): icmp_seq=2 ttl=128 time=0.518 ms
64 bytes from NT4S (192.168.2.250): icmp_seq=3 ttl=128 time=0.578 ms

--- nt4s.abmas.biz ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2003ms
rtt min/avg/max/mdev = 0.518/3.773/10.223/4.560 ms
</screen>
		It can. Great.
		</para></step>

	  <step><para><indexterm>
		<primary>smbclient</primary>
	      </indexterm>
		Validate that the resources on the NT4 PDC can be listed:
<screen>
&rootprompt; smbclient -L nt4s -UAdministrator%not24get

        Sharename      Type      Comment
        ---------      ----      -------
        NETLOGON       Disk      Logon server share
        IPC$           IPC       Remote IPC
        UserProfiles   Disk      All Network User Profiles

        Server               Comment
        ---------            -------
        NT4S

        Workgroup            Master
        ---------            -------
        MEGANET              NT4S
</screen>
		This looks good.
		</para></step>

	  <step><para><indexterm>
		<primary>Domain SID</primary>
	      </indexterm><indexterm>
		<primary>net</primary>
		<secondary>rpc</secondary>
		<tertiary>getsid</tertiary>
	      </indexterm>
		At this point, it is necessary to fetch the Domain SID from the NT4 PDC and
		apply that to the Samba-3 BDC (soon to be PDC):
<screen>
&rootprompt; net rpc getsid -S NT4S -W MEGANET
Storing SID S-1-5-21-1988699175-926296742-1295600288 for 
                              Domain MEGANET in secrets.tdb
</screen>
		Done.
		</para></step>

	  <step><para><indexterm>
		<primary>secrets.tdb</primary>
	      </indexterm><indexterm>
		<primary>validate</primary>
	      </indexterm><indexterm>
		<primary>tdbdump</primary>
	      </indexterm>
		At this point, you can validate that the information is correct in the
		<filename>secrets.tdb</filename> file, as shown here:
<screen>
&rootprompt; tdbdump /etc/samba/secrets.tdb
{
key = "SECRETS/SID/MASSIVE"
data = "\01\04\00\00\00\00\00\05\15\00\00\00'$\89v\A6*67\A0J9M\
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/LDAP_BIND_PW/cn=Manager,dc=abmas,dc=biz"
data = "not24get\00"
}
</screen>
		This has returned the information expected.
		</para></step>

<note><para>
The <command>tdbdump</command> utility is a utility that you can build from the Samba source
code tree. Not all Linux binary distributions include this tool. If it is missing from your
Linux distribution you will need to build this yourself, or else for-go its use.
</para></note>

	  <step><para><indexterm>
		<primary>net</primary>
		<secondary>rpc</secondary>
		<tertiary>join</tertiary>
	      </indexterm>
		We are ready to join the NT4 Domain as a BDC by executing the following:
<screen>
&rootprompt; net rpc join -S NT4S -W MEGANET -U Administrator%not24get
Joined domain MEGANET.
</screen>
		Done.
		</para></step>	

	  <step><para><indexterm>
		<primary>net</primary>
		<secondary>rpc</secondary>
		<tertiary>vampire</tertiary>
	      </indexterm>
		The Samba-3 BDC is now ready to receive the NT4 PDC accounts database, as shown here:
<screen>
&rootprompt; net rpc vampire -S NT4S
Fetching DOMAIN database
SAM_DELTA_DOMAIN_INFO not handled
Creating account: Administrator
Creating account: Guest
Creating account: NT4S$
Creating account: massive$
Creating account: barryf
Creating account: gdaison
Creating account: atrikhoffer
Creating account: hramsbotham
Creating account: fsellerby
Creating account: jrhapsody
Group members of Domain Admins:
Group members of Domain Users: NT4S$(primary),massive$(primary),
Group members of Domain Guests: nobody(primary),
Group members of rubberboot:
Group members of engineers:
Group members of accounting:
Group members of catalyst:
Group members of shipping:
Group members of receiving:
Group members of marketiod:
Group members of sales:
Fetching BUILTIN database
SAM_DELTA_DOMAIN_INFO not handled
</screen>
		</para></step>

	  <step><para><indexterm>
		<primary>domain master</primary>
	      </indexterm><indexterm>
		<primary>PDC</primary>
	      </indexterm>
		Edit the &smb.conf; file to  reset the parameter 
		<smbconfoption><name>domain master</name><value>Yes</value></smbconfoption> so that
		the Samba server functions as a PDC for the purpose of migration.
                </para></step>
	</procedure>

<example id ="ch8-LDIF">
<title>LDAP Preload LDIF file &smbmdash; <filename>preload.LDIF</filename></title>
<screen>
dn: dc=abmas,dc=biz
objectClass: dcObject
objectClass: organization
dc: abmas
o: Abmas Demo
description: POSIX and Samba LDAP Identity Database
structuralObjectClass: organization

dn: cn=Manager,dc=abmas,dc=biz
objectClass: organizationalRole
cn: Manager
description: Directory Manager
structuralObjectClass: organizationalRole

dn: ou=People,dc=abmas,dc=biz
objectClass: top
objectClass: organizationalUnit
ou: People
structuralObjectClass: organizationalUnit

dn: ou=Groups,dc=abmas,dc=biz
objectClass: top
objectClass: organizationalUnit
ou: Groups
structuralObjectClass: organizationalUnit

dn: ou=Idmap,dc=abmas,dc=biz
objectClass: top
objectClass: organizationalUnit
ou: Idmap
structuralObjectClass: organizationalUnit

dn: ou=Domains,dc=abmas,dc=biz
objectClass: organizationalUnit
ou: Domains
structuralObjectClass: organizationalUnit
</screen>
</example>

	</sect2>

	<sect2>
	<title>NT4 Migration Using tdbsam Backend</title>

	<para>
	In this example, you have chosen to change the Domain name of the NT4 server from
	<constant>DRUGPREP</constant> to <constant>MEGANET</constant> prior to the use
	of the vampire (migration) tool. This migration process makes use of Linux system tools
	(like <command>useradd</command>) to add the accounts that are migrated into the 
	UNIX/Linux <filename>/etc/passwd</filename>, and <filename>/etc/group</filename>
	databases. These entries must therefore be present, and correct options specified,
	in your &smb.conf; file or else the migration does not work as it should.
	</para>

	<procedure>
		<step><para>
		Prepare a Samba-3 server precisely per the instructions shown in Chapter 5.
		Set the workgroup name to <constant>MEGANET</constant>.
		</para></step>

	  <step><para><indexterm>
		<primary>domain master</primary>
	      </indexterm><indexterm>
		<primary>BDC</primary>
	      </indexterm>
		Edit the &smb.conf; file to temporarily change the parameter 
		<smbconfoption><name>domain master</name><value>No</value></smbconfoption> so
		the Samba server functions as a BDC for the purpose of migration.
                </para></step>

		<step><para>
		Start Samba as you have done previously.
		</para></step>

	  <step><para><indexterm>
		<primary>net</primary>
		<secondary>rpc</secondary>
		<tertiary>join</tertiary>
	      </indexterm>
		Join the NT4 Domain as a BDC, as shown here:
<screen>
&rootprompt; net rpc join -S oldnt4pdc -W MEGANET -UAdministrator%not24get
Joined domain MEGANET.
</screen>
		</para></step>

		<step><para><indexterm>
		<primary>net</primary>
		<secondary>rpc</secondary>
		<tertiary>vampire</tertiary>
	      </indexterm>
		You may vampire the accounts from the NT4 PDC by executing the command, as shown here:
<screen>
&rootprompt; net rpc vampire -S oldnt4pdc -U Administrator%not24get
Fetching DOMAIN database
SAM_DELTA_DOMAIN_INFO not handled
Creating unix group: 'Domain Admins'
Creating unix group: 'Domain Users'
Creating unix group: 'Domain Guests'
Creating unix group: 'Engineers'
Creating unix group: 'Marketoids'
Creating account: Administrator
Creating account: Guest
Creating account: oldnt4pdc$
Creating account: jacko
Creating account: maryk
Creating account: bridge
Creating account: sharpec
Creating account: jimbo
Creating account: dhenwick
Creating account: dork
Creating account: blue
Creating account: billw
Creating account: massive$
Group members of Engineers: Administrator,
                 sharpec(primary),bridge,billw(primary),dhenwick
Group members of Marketoids: Administrator,jacko(primary),
                maryk(primary),jimbo,blue(primary),dork(primary)
Creating unix group: 'Gnomes'
Fetching BUILTIN database
SAM_DELTA_DOMAIN_INFO not handled
Creating unix group: 'Account Operators'
Creating unix group: 'Administrators'
Creating unix group: 'Backup Operators'
Creating unix group: 'Guests'
Creating unix group: 'Print Operators'
Creating unix group: 'Replicator'
Creating unix group: 'Server Operators'
Creating unix group: 'Users'
</screen>
		</para></step>

	  <step><para><indexterm>
		<primary>pdbedit</primary>
	      </indexterm>
		At this point, we can validate our migration. Let's look at the accounts
		in the form as they would be seen in a smbpasswd file. This achieves that:
<screen>
&rootprompt; pdbedit -Lw
Administrator:505:84B0D8E14D158FF8417EAF50CFAC29C3:
     AF6DD3FD4E2EA8BDE1695A3F05EFBF52:[UX         ]:LCT-3DF7AA9F:
jimbo:512:6E9A2A51F64A1BD5C187B8085FE1D9DF:
     CDF7E305E639966E489A0CEFB95EE5E0:[UX         ]:LCT-3E9362BC:
sharpec:511:E4301A7CD8FDD1EC6BBF9BC19CDF8151:
     7000255938831D5B948C95C1931534C5:[UX         ]:LCT-3E8B42C4:
dhenwick:513:DCD8886141E3F892AAD3B435B51404EE:
     2DB36465949CB938DD98C312EFDC2639:[UX         ]:LCT-3E939F41:
bridge:510:3FE6873A43101B46417EAF50CFAC29C3:
     891741F481AF111B4CAA09A94016BD01:[UX         ]:LCT-3E8B4291:
blue:515:256D41D2559BB3D2AAD3B435B51404EE:
     9CCADDA4F7D281DD0FAD321478C6F971:[UX         ]:LCT-3E939FDC:
diamond$:517:6C8E7B64EDCDBC4218B6345447A4454B:
     3323AC63C666CFAACB60C13F65D54E9A:[S          ]:LCT-00000000:
oldnt4pdc$:507:3E39430CDCABB5B09ED320D0448AE568:
     95DBAF885854A919C7C7E671060478B9:[S          ]:LCT-3DF7AA9F:
Guest:506:XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:
     XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX:[DUX        ]:LCT-3E93A008:
billw:516:85380CA7C21B6EBE168C8150662AF11B:
     5D7478508293709937E55FB5FBA14C17:[UX         ]:LCT-3FED7CA1:
dork:514:78C70DDEC35A35B5AAD3B435B51404EE:
     0AD886E015AC595EC0AF40E6C9689E1A:[UX         ]:LCT-3E939F9A:
jacko:508:BC472F3BF9A0A5F63832C92FC614B7D1:
     0C6822AAF85E86600A40DC73E40D06D5:[UX         ]:LCT-3E8B4242:
maryk:509:3636AB7E12EBE79AB79AE2610DD89D4C:
     CF271B744F7A55AFDA277FF88D80C527:[UX         ]:LCT-3E8B4270:
</screen>
		</para></step>

		<step><para><indexterm>
		<primary>pdbedit</primary>
	      </indexterm>
		An expanded view of a user account entry shows more of what was
		obtained from the NT4 PDC:
<screen>
sleeth:~ # pdbedit -Lv maryk
Unix username:        maryk
NT username:          maryk
Account Flags:        [UX         ]
User SID:             S-1-5-21-5672968813-926296742-3245673225-1003
Primary Group SID:    S-1-5-21-5672968813-926296742-3245673225-1007
Full Name:            Mary Kathleen
Home Directory:       \\diamond\maryk
HomeDir Drive:        X:
Logon Script:         scripts\logon.bat
Profile Path:         \\diamond\profiles\maryk
Domain:               MEGANET
Account desc:         Peace Maker
Workstations:
Munged dial:
Logon time:           0
Logoff time:          Mon, 18 Jan 2038 20:14:07 GMT
Kickoff time:         Mon, 18 Jan 2038 20:14:07 GMT
Password last set:    Wed, 02 Apr 2003 13:05:04 GMT
Password can change:  0
Password must change: Mon, 18 Jan 2038 20:14:07 GMT
</screen>
		</para></step>

	  <step><para><indexterm>
		<primary>net</primary>
		<secondary>group</secondary>
	      </indexterm>
		And this command lists the long names of the groups that have been
		imported (vampired) from the NT4 PDC:
<screen>
&rootprompt; net group -l -Uroot%not24get -Smassive

Group name            Comment
-----------------------------
Engineers             Snake Oil Engineers
Marketoids            Untrustworthy Hype Vendors
Gnomes                Plain Vanilla Garden Gnomes
Replicator            Supports file replication in a domain
Guests                Users granted guest access to the computer/domain
Administrators        Members can fully administer the computer/domain
Users                 Ordinary users
</screen>
		Everything looks well and in order.
		</para></step>

	  <step><para><indexterm>
		<primary>domain master</primary>
	      </indexterm><indexterm>
		<primary>PDC</primary>
	      </indexterm>
		Edit the &smb.conf; file to  reset the parameter 
		<smbconfoption><name>domain master</name><value>Yes</value></smbconfoption> so
		the Samba server functions as a PDC for the purpose of migration.
                </para></step>
	</procedure>
	</sect2>

	<sect2>
		<title>Key Points Learned</title>

		<para>
		Migration of an NT4 PDC database to a Samba-3 PDC is possible.
		</para>

		<itemizedlist>
			<listitem><para>
			An LDAP backend is a suitable vehicle for NT4 migrations.
			</para></listitem>

			<listitem><para>
			A tdbsam backend can be used to perform a migration.
			</para></listitem>

			<listitem><para>
			Multiple NT4 Domains can be merged into a single Samba-3
			Domain.
			</para></listitem>

			<listitem><para>
			The net Samba-3 Domain most likely requires some
			administration and updating before going live.
			</para></listitem>
		</itemizedlist>

	</sect2>

</sect1>

<sect1>
	<title>Questions and Answers</title>

	<para>
	</para>

	<qandaset defaultlabel="chap08qa" type="number">
	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>clean database</primary>
	      </indexterm>
		Why must I start each migration with a clean database?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>merge</primary>
	      </indexterm>
		This is a recommendation that permits the data from each NT4 Domain to
		be kept separate until you are ready to merge them. Also, if you do not do this,
		you may find errors due to users or groups from multiple Domains having the
		same name, but different SIDs. It is better to permit each migration to complete
		without undue errors and then to handle the merging of vampired data under
		proper supervision.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>Domain SID</primary>
	      </indexterm>
		Is it possible to set my Domain SID to anything I like?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>auto-generated SID</primary>
	      </indexterm><indexterm>
		<primary>SID</primary>
	      </indexterm><indexterm>
		<primary>Domain SID</primary>
	      </indexterm>
		Yes, so long as the SID you create has the same structure as an auto-generated SID.
		The typical SID looks like this: S-1-5-21-XXXXXXXXXX-XXXXXXXXXX-XXXXXXXXXX, where
		the XXXXXXXXXX can be any number with from 6 to 10 digits. On the other hand, why
		would you really want to create your own SID? I cannot think of a good reason.
		You may want to set the SID to one that is already in use somewhere on your network,
		but that is a little different from straight out creating your own Domain SID.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>/etc/passwd</primary>
	      </indexterm><indexterm>
		<primary>/etc/group</primary>
	      </indexterm><indexterm>
		<primary>tdbsam</primary>
	      </indexterm><indexterm>
		<primary>passdb backend</primary>
	      </indexterm><indexterm>
		<primary>accounts</primary>
		<secondary>user</secondary>
	      </indexterm><indexterm>
		<primary>accounts</primary>
		<secondary>group</secondary>
	      </indexterm><indexterm>
		<primary>accounts</primary>
		<secondary>Domain</secondary>
	      </indexterm>
		When using a tdbsam passdb backend, why must I have all Domain user and group accounts
		in <filename>/etc/passwd</filename> and <filename>/etc/group</filename>?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>UID</primary>
	      </indexterm><indexterm>
		<primary>GID</primary>
	      </indexterm><indexterm>
		<primary>smbpasswd</primary>
	      </indexterm><indexterm>
		<primary>/etc/passwd</primary>
	      </indexterm><indexterm>
		<primary>Posix</primary>
	      </indexterm><indexterm>
		<primary>LDAP database</primary>
	      </indexterm>
		Samba-3 must be able to tie all user and group account SIDs to a UNIX UID or GID. Samba
		does not fabricate the UNIX IDs from thin air, but rather requires them to be located
		in a suitable place. 
		</para>

		<para>
		When migrating a <filename>smbpasswd</filename> file to an LDAP backend, the
		UID of each account is taken together with the account information in the 
		<filename>/etc/passwd</filename> and both sets of data are used to create the account
		entrt in the LDAP database. 
		</para>

		<para>
		If you elect to create the Posix account also, the entire UNIX account is copied to the 
		LDAP backend. The same occurs with NT groups and UNIX groups. At the conclusion of 
		migration to the LDAP database, the accounts may be removed from the UNIX database files. 
		In short then, all UNIX and Windows networking accounts, both in tdbsam as well as in 
		LDAP, require UIDs/GIDs.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>validate</primary>
	      </indexterm><indexterm>
		<primary>connectivity</primary>
	      </indexterm><indexterm>
		<primary>migration</primary>
	      </indexterm>
		Why did you validate connectivity before attempting migration?
		</para>

	</question>
	<answer>

		<para>
		Access validation before attempting to migrate NT4 Domain accounts helps to pin-point
		potential problems that may otherwise affect or impede account migration. I am always
		mindful of the 4P's of migration &smbmdash; Planning Prevents Poor Performance.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

		<para>
		How would you merge 10 tdbsam-based domains into an LDAP database?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>risk</primary>
	      </indexterm><indexterm>
		<primary>dump</primary>
	      </indexterm><indexterm>
		<primary>tdbsam</primary>
	      </indexterm><indexterm>
		<primary>Samba Domain</primary>
	      </indexterm><indexterm>
		<primary>UID</primary>
	      </indexterm><indexterm>
		<primary>GID</primary>
	      </indexterm><indexterm>
		<primary>pdbedit</primary>
	      </indexterm><indexterm>
		<primary>transfer</primary>
	      </indexterm><indexterm>
		<primary>smbpasswd</primary>
	      </indexterm><indexterm>
		<primary>LDAP</primary>
	      </indexterm><indexterm>
		<primary>tool</primary>
	      </indexterm>
		If you have 10 tdbsam Samba Domains, there is considerable risk that there are a number of
		accounts that have the same UNIX identifier (UID/GID). This means that you almost 
		certainly have to edit a lot of data. It would be easiest to dump each database in smbpasswd
		file format and then manually edit all records to ensure that each has a unique UID. Each
		file can then be imported a number of ways. You can use the <command>pdbedit</command> tool,
		to affect a transfer from the smbpasswd file to LDAP, or you can migrate them en masse to
		tdbsam and then to LDAP. The final choice is yours. Just remember to verify all accounts that
		you have migrated before handing over access to a user. After all, too many users with a bad
		migration experience may threaten your career.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>machine accounts</primary>
	      </indexterm><indexterm>
		<primary>accounts</primary>
		<secondary>machine</secondary>
	      </indexterm>
		I want to change my Domain name after I migrate all accounts from an NT4 Domain to a 
		Samba-3 Domain.  Does it make any sense to migrate the machine accounts in that case?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>registry</primary>
	      </indexterm><indexterm>
		<primary>un-join</primary>
	      </indexterm><indexterm>
		<primary>rejoin</primary>
	      </indexterm><indexterm>
		<primary>tattooing</primary>
	      </indexterm>
		I would recommend not. The machine accounts should still work, but there are registry entries
		on each Windows NT4 and upward client that have a tattoo of the old domain name. If you
		un-join the domain and then rejoin the newly renamed Samba-3 Domain, you can be certain to avoid
		this tattooing effect.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>multiple group mappings</primary>
	      </indexterm>
		After merging multiple NT4 Domains into a Samba-3 Domain, I lost all multiple group mappings. Why?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>/etc/passwd</primary>
	      </indexterm><indexterm>
		<primary>/etc/group</primary>
	      </indexterm>
		Samba-3 currently does not implement multiple group membership internally. If you use the Windows 
		NT4 Domain User Manager to manage accounts and you have an LDAP backend, the multiple group
		membership is stored in the Posix groups area. If you use either tdbsam or smbpasswd backend,
		then multiple group membership is handled through the UNIX groups file. When you dump the user
		accounts no group account information is provided. When you edit (change) UIDs and GIDs in each
		file to which you migrated the NT4 Domain data, do not forget to edit the UNIX <filename>/etc/passwd</filename>
		and <filename>/etc/group</filename> information also. That is where the multiple group information
		is most closely at your fingertips.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

		<para>
		How can I reset group membership after loading the account information into the LDAP database?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>SRVTOOLS.EXE</primary>
	      </indexterm>
		You can use the NT4 Domain User Manager that can be downloaded from the Microsoft Web site. The
		installation file is called <filename>SRVTOOLS.EXE</filename>.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>group names</primary>
	      </indexterm>
		What are the limits or constraints that apply to group names?
		</para>

	</question>
	<answer>

	    <para><indexterm>
		<primary>limit</primary>
	      </indexterm><indexterm>
		<primary>shadow-utils</primary>
	      </indexterm><indexterm>
		<primary>groupadd</primary>
	      </indexterm><indexterm>
		<primary>groupdel</primary>
	      </indexterm><indexterm>
		<primary>groupmod</primary>
	      </indexterm><indexterm>
		<primary>account names</primary>
	      </indexterm>
		A Windows 200x group name can be up to 254 characters long, while in Windows NT4 the group
		name is limited to 20 characters. Most UNIX systems limit this to 32 characters. Windows 
		groups can contain upper- and lower-case characters, as well as spaces.
		Many UNIX system do not permit the use of upper-case characters, and some do not permit the
		space character either. A number of systems (i.e., Linux) work fine with both upper-case
		and space characters in group names, but the shadow-utils package that provides the group
		control functions (<command>groupadd, groupmod, groupdel</command>, and so on) do not permit them.
		Also, a number of UNIX systems management tools enforce their own particular interpretation
		of the Posix standards, and likewise do not permit upper-case or space characters in group
		or user account names. You have to experiment with your system to find what its 
		peculiarities are.
		</para>

	</answer>
	</qandaentry>

	<qandaentry>
	<question>

	    <para><indexterm>
		<primary>vampire</primary>
	      </indexterm>
		My Windows NT4 PDC has 323,000 user accounts. How long will it take to migrate them to a Samba-3
		LDAP backend system using the vampire process?
		</para>

	</question>
	<answer>

		<para>
		UNIX UIDs and GIDs on most UNIX systems use an unsigned short or an unsigned integer. Recent Linux
		kernels support at least a much larger number. On systems that have a 16-bit constraint on UID/GIDs,
		you would not be able to migrate 323,000 accounts because this number can not fit into a 16-bit unsigned
		integer. UNIX/Linux systems that have a 32-bit UID/GID can easily handle this number of accounts. 
		Please check this carefully before you attempt to effect a migration using the vampire process.
		</para>

	    <para><indexterm>
		<primary>Migration speed</primary>
	      </indexterm>
		Migration speed depends much on the processor speed, the network speed, disk I/O capability, and
		LDAP update overheads. On a dual processor AMD MP1600+ with 1 GB memory, that was mirroring LDAP
		to a second identical system over 1 gigabit ethernet, I was able to migrate around 180 user accounts
		per minute. Migration would obviously go much faster if LDAP mirroring is turned off during the migration.
		</para>

	</answer>
	</qandaentry>

	</qandaset>

</sect1>

</chapter>