path: root/docs/Samba3-ByExample/SBE-Appendix1.xml

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

<appendix id="appendix">
  <title>A Collection of Useful Tidbits</title>

	<para>
	<indexterm><primary>material</primary></indexterm>
	<indexterm><primary>domain</primary><secondary>joining</secondary></indexterm>
	Information presented here is considered to be either basic or well-known material that is informative
	yet helpful. Over the years, I have observed an interesting behavior. There is an expectation that
	the process for joining a Windows client to a Samba-controlled Windows domain may somehow involve steps
	different from doing so with Windows NT4 or a Windows ADS domain. Be assured that the steps are identical,
	as shown in the example given below.
	</para>

<sect1 id="domjoin">
<title>Joining a Domain: Windows 200x/XP Professional</title>

	<para>
	<indexterm><primary>joining a domain</primary></indexterm>
	Microsoft Windows NT/200x/XP Professional platforms can participate in Domain Security.
	This section steps through the process for making a Windows 200x/XP Professional machine a
	member of a Domain Security environment. It should be noted that this process is identical
	when joining a domain that is controlled by Windows NT4/200x as well as a Samba PDC.
	</para>

	<procedure>
	<title>Steps to Join a Domain</title>

		<step><para>
		Click <guimenu>Start</guimenu>.
		</para></step>

		<step><para>
		Right-click <guimenu>My Computer</guimenu>, and then select <guimenuitem>Properties</guimenuitem>.
		</para></step>

		<step><para>
		The opening panel is the same one that can be reached by clicking <guimenu>System</guimenu> on the Control Panel.
		See <link linkend="swxpp001"></link>.
		<figure id="swxpp001"><imagefile>wxpp001</imagefile><title>The General Panel.</title></figure>
		</para></step>

		<step><para>
		Click the <guimenu>Computer Name</guimenu> tab.
		This panel shows the <guimenuitem>Computer Description</guimenuitem>, the <guimenuitem>Full computer name</guimenuitem>,
		and the <guimenuitem>Workgroup</guimenuitem> or <guimenuitem>Domain name</guimenuitem>.
		</para>

		<para>
		Clicking the <guimenu>Network ID</guimenu> button launches the configuration wizard. Do not use this with
		Samba-3. If you wish to change the computer name, or join or leave the domain, click the <guimenu>Change</guimenu> button.
		See <link linkend="swxpp004"></link>.
		<figure id="swxpp004"><imagefile>wxpp004</imagefile><title>The Computer Name Panel.</title></figure>
		</para></step>

		<step><para>
		Click on <guimenu>Change</guimenu>. This panel shows that our example machine (TEMPTATION) is in a workgroup called WORKGROUP.
		We join the domain called MIDEARTH. See <link linkend="swxpp006"></link>.
		<figure id="swxpp006"><imagefile>wxpp006</imagefile><title>The Computer Name Changes Panel</title></figure>
		</para></step>

		<step><para>
		Enter the name <guimenu>MIDEARTH</guimenu> in the field below the Domain radio button.
		</para>

		<para>
		This panel shows that our example machine (TEMPTATION) is set to join the domain called MIDEARTH. See <link linkend="swxpp007"></link>.
		<figure id="swxpp007"><imagefile>wxpp007</imagefile><title>The Computer Name Changes Panel &smbmdash; Domain MIDEARTH</title></figure>
		</para></step>

		<step><para>
		Now click the <guimenu>OK</guimenu> button. A dialog box should appear to allow you to provide the credentials (username and password)
		of a domain administrative account that has the rights to add machines to the domain.
		</para>

		<para>
		Enter the name <quote>root</quote> and the root password from your Samba-3 server. See <link linkend="swxpp008"></link>.
		<figure id="swxpp008"><imagefile>wxpp008</imagefile><title>Computer Name Changes &smbmdash; User name and Password Panel</title></figure>
		</para></step>

		<step><para>
		Click <guimenu>OK</guimenu>.
		</para>

		<para>
		The <quote>Welcome to the MIDEARTH domain</quote> dialog box should appear. At this point, the machine must be rebooted.
		Joining the domain is now complete.
		</para></step>

	</procedure>

	<para>
	<indexterm><primary>Active Directory</primary></indexterm>
	<indexterm><primary>DNS</primary></indexterm>
	The screen capture shown in <link linkend="swxpp007"/> has a button labeled <guimenu>More...</guimenu>. This button opens a
	panel in which you can set (or change) the Primary DNS suffix of the computer. This is a parameter that mainly affects members
	of Microsoft Active Directory. Active Directory is heavily oriented around the DNS namespace.
	</para>

	<para>
	<indexterm><primary>Netlogon</primary></indexterm>
	<indexterm><primary>DNS</primary><secondary>dynamic</secondary></indexterm>
	Where NetBIOS technology uses WINS as well as UDP broadcast as key mechanisms for name resolution, Active Directory servers
	register their services with the Microsoft Dynamic DNS server. Windows clients must be able to query the correct DNS server
	to find the services (like which machines are domain controllers or which machines have the Netlogon service running).
	</para>

	<para>
	<indexterm><primary>DNS</primary><secondary>suffix</secondary></indexterm>
	The default setting of the Primary DNS suffix is the Active Directory domain name. When you change the Primary DNS suffix,
	this does not affect domain membership, but it can break network browsing and the ability to resolve your computer name to
	a valid IP address.
	</para>

	<para>
	The Primary DNS suffix parameter principally affects MS Windows clients that are members of an Active Directory domain.
	Where the client is a member of a Samba domain, it is preferable to leave this field blank.
	</para>

	<para>
	<indexterm><primary>Group Policy</primary></indexterm>
	According to Microsoft documentation, <quote>If this computer belongs to a group with <constant>Group Policy</constant>
	enabled on <command>Primary DNS suffice of this computer</command>, the string specified in the Group Policy is used
	as the primary DNS suffix and you might need to restart your computer to view the correct setting. The local setting is
	used only if Group Policy is disabled or unspecified.</quote>
	</para>

</sect1>

<sect1>
	<title>Samba System File Location</title>

      <para><indexterm>
	  <primary>default installation</primary>
	</indexterm><indexterm>
	  <primary>/usr/local/samba</primary>
	</indexterm><indexterm>
	  <primary>/usr/local</primary>
	</indexterm>
	One of the frustrations expressed by subscribers to the Samba mailing lists revolves around the choice of where the default Samba Team
	build and installation process locates its Samba files. The location, chosen in the early 1990s, for the default installation is
	in the <filename>/usr/local/samba</filename> directory. This is a perfectly reasonable location, particularly given all the other
	Open Source software that installs into the <filename>/usr/local</filename> subdirectories.
	</para>

	<para>
	Several UNIX vendors, and Linux vendors in particular, elected to locate the Samba files in a location other than the Samba Team
	default. 
	</para>

      <para><indexterm>
	  <primary>Free Standards Group</primary>
	  <see>FSG</see>
	</indexterm><indexterm>
	  <primary>FSG</primary>
	</indexterm><indexterm>
	  <primary>Linux Standards Base</primary>
	  <see>LSB</see>
	</indexterm><indexterm>
	  <primary>LSB</primary>
	</indexterm><indexterm>
	  <primary>File Hierarchy System</primary>
	  <see>FHS</see>
	</indexterm><indexterm>
	  <primary>FHS</primary>
	</indexterm><indexterm>
	  <primary>file locations</primary>
	</indexterm><indexterm>
	  <primary>/etc/samba</primary>
	</indexterm><indexterm>
	  <primary>/usr/sbin</primary>
	</indexterm><indexterm>
	  <primary>/usr/bin</primary>
	</indexterm><indexterm>
	  <primary>/usr/share</primary>
	</indexterm><indexterm>
	  <primary>/usr/share/swat</primary>
	</indexterm><indexterm>
	  <primary>/usr/lib/samba</primary>
	</indexterm><indexterm>
	  <primary>/usr/share/samba/swat</primary>
	</indexterm><indexterm>
	  <primary>SWAT</primary>
	</indexterm><indexterm>
	  <primary>VFS modules</primary>
	</indexterm>
	Linux vendors, working in conjunction with the Free Standards Group (FSG), Linux Standards Base (LSB), and File Hierarchy	
	System (FHS), have elected to locate the configuration files under the <filename>/etc/samba</filename> directory, common binary
	files (those used by users) in the <filename>/usr/bin</filename> directory, and the administrative files (daemons) in the
	<filename>/usr/sbin</filename> directory. Support files for the Samba Web Admin Tool (SWAT) are located under the
	<filename>/usr/share</filename> directory, either in <filename>/usr/share/samba/swat</filename> or in
	<filename>/usr/share/swat</filename>. There are additional support files for <command>smbd</command> in the
	<filename>/usr/lib/samba</filename> directory tree. The files located there include the dynamically loadable modules for the
	passdb backend as well as for the VFS modules.
	</para>

      <para><indexterm>
	  <primary>/var/lib/samba</primary>
	</indexterm><indexterm>
	  <primary>/var/log/samba</primary>
	</indexterm><indexterm>
	  <primary>run-time control files</primary>
	</indexterm>
	Samba creates runtime control files and generates log files. The runtime control files (tdb and dat files) are stored in
	the <filename>/var/lib/samba</filename> directory. Log files are created in <filename>/var/log/samba.</filename>
	</para>

	<para>
	When Samba is built and installed using the default Samba Team process, all files are located under the 
	<filename>/usr/local/samba</filename> directory tree. This makes it simple to find the files that Samba owns.
	</para>

      <para><indexterm>
	  <primary>smbd</primary>
	  <secondary>location of files</secondary>
	</indexterm>
	One way to find the Samba files that are installed on your UNIX/Linux system is to search for the location
	of all files called <command>smbd</command>. Here is an example:
<screen>
&rootprompt; find / -name smbd -print
</screen>
	You can find the location of the configuration files by running:
<screen>
&rootprompt; /path-to-binary-file/smbd -b | more
...
Paths:
   SBINDIR: /usr/sbin
   BINDIR: /usr/bin
   SWATDIR: /usr/share/samba/swat
   CONFIGFILE: /etc/samba/smb.conf
   LOGFILEBASE: /var/log/samba
   LMHOSTSFILE: /etc/samba/lmhosts
   LIBDIR: /usr/lib/samba
   SHLIBEXT: so
   LOCKDIR: /var/lib/samba
   PIDDIR: /var/run/samba
   SMB_PASSWD_FILE: /etc/samba/smbpasswd
   PRIVATE_DIR: /etc/samba
...
</screen>
	If you wish to locate the Samba version, just run:
<screen>
&rootprompt; /path-to-binary-file/smbd -V
Version 3.0.20-SUSE
</screen>
	</para>

	<para>
	Many people have been caught by installation of Samba using the default Samba Team process when it was already installed
	by the platform vendor's method. If your platform uses RPM format packages, you can check to see if Samba is installed by
	executing:<indexterm>
	  <primary>rpm</primary>
	</indexterm>
<screen>
&rootprompt; rpm -qa | grep samba
samba3-pdb-3.0.20-1
samba3-vscan-0.3.6-0
samba3-winbind-3.0.20-1
samba3-3.0.20-1
samba3-python-3.0.20-1
samba3-utils-3.0.20-1
samba3-doc-3.0.20-1
samba3-client-3.0.20-1
samba3-cifsmount-3.0.20-1
	</screen><indexterm>
	  <primary>package names</primary>
	</indexterm>
	The package names, of course, vary according to how the vendor, or the binary package builder, prepared them.
	</para>

</sect1>

<sect1>
	<title>Starting Samba</title>

      <para><indexterm>
	  <primary>daemon</primary>
	</indexterm>
	Samba essentially consists of two or three daemons. A daemon is a UNIX application that runs in the background and provides services.
	An example of a service is the Apache Web server for which the daemon is called <command>httpd</command>. In the case of Samba, there
	are three daemons, two of which are needed as a minimum.
	</para>

	<para>
	The Samba server is made up of the following daemons:
	</para>

<example id="ch12SL">
<title>A Useful Samba Control Script for SUSE Linux</title>
<screen>
#!/bin/bash
#
# Script to start/stop samba
# Locate this in /sbin as a file called 'samba'

RCD=/etc/rc.d

if [ z$1 == 'z' ]; then
        echo $0 - No arguments given; must be start or stop.
        exit
fi

if [ $1 == 'start' ]; then
        ${RCD}/nmb start
        ${RCD}/smb start
        ${RCD}/winbind start

fi
if [ $1 == 'stop' ]; then
        ${RCD}/smb stop
        ${RCD}/winbind stop
        ${RCD}/nmb stop
fi
if [ $1 == 'restart' ]; then
        ${RCD}/smb stop
        ${RCD}/winbind stop
        ${RCD}/nmb stop
        sleep 5
        ${RCD}/nmb start
        ${RCD}/smb start
        ${RCD}/winbind start
fi
exit 0
</screen>
</example>

	<variablelist>
		<varlistentry><term>nmbd</term>
			<listitem><para>
			<indexterm><primary>smbd</primary></indexterm>
			<indexterm><primary>starting samba</primary><secondary>smbd</secondary></indexterm>
			This daemon handles all name registration and resolution requests. It is the primary vehicle involved
			in network browsing. It handles all UDP-based protocols. The <command>nmbd</command> daemon should
			be the first command started as part of the Samba startup process.
			</para></listitem>
		</varlistentry>

		<varlistentry><term>smbd</term>
			<listitem><para>
			<indexterm><primary>nmbd</primary></indexterm>
			<indexterm><primary>starting samba</primary><secondary>nmbd</secondary></indexterm>
			This daemon handles all TCP/IP-based connection services for file- and print-based operations. It also
			manages local authentication. It should be started immediately following the startup of <command>nmbd</command>.
			</para></listitem>
		</varlistentry>

		<varlistentry><term>winbindd</term>
			<listitem><para>
			<indexterm><primary>winbindd</primary></indexterm>
			<indexterm><primary>starting samba</primary><secondary>winbindd</secondary></indexterm>
			This daemon should be started when Samba is a member of a Windows NT4 or ADS domain. It is also needed when
			Samba has trust relationships with another domain. The <command>winbindd</command> daemon will check the
			&smb.conf; file for the presence of the <parameter>idmap uid</parameter> and <parameter>idmap gid</parameter>
			parameters. If they are not found, <command>winbindd</command> bails out and refuses to start.
			</para></listitem>
		</varlistentry>
	</variablelist>

	<para>
	When Samba has been packaged by an operating system vendor, the startup process is typically a custom feature of its
	integration into the platform as a whole. Please refer to your operating system platform administration manuals for
	specific information pertaining to correct management of Samba startup.
	</para>

<example id="ch12RHscript">
<title>A Sample Samba Control Script for Red Hat Linux</title>
<screen>
#!/bin/sh
#
# chkconfig: 345 81 35
# description: Starts and stops the Samba smbd and nmbd daemons \
#              used to provide SMB network services.

# Source function library.
. /etc/rc.d/init.d/functions
# Source networking configuration.
. /etc/sysconfig/network
# Check that networking is up.
[ ${NETWORKING} = "no" ] &amp;&amp; exit 0
CONFIG=/etc/samba/smb.conf
# Check that smb.conf exists.
[ -f $CONFIG ] || exit 0

# See how we were called.
case "$1" in
  start)
        echo -n "Starting SMB services: "
        daemon smbd -D; daemon nmbd -D; echo;
        touch /var/lock/subsys/smb
        ;;
  stop)
        echo -n "Shutting down SMB services: "
        smbdpids=`ps guax | grep smbd | grep -v grep | awk '{print $2}'`
        for pid in $smbdpids; do
                kill -TERM $pid
        done
        killproc nmbd -TERM; rm -f /var/lock/subsys/smb
        echo ""
        ;;
  status)
        status smbd; status nmbd;
        ;;
  restart)
        echo -n "Restarting SMB services: "
        $0 stop; $0 start;
        echo "done."
        ;;
  *)
        echo "Usage: smb {start|stop|restart|status}"
        exit 1
esac
</screen>
</example>

      <para><indexterm>
	  <primary>samba control script</primary>
	</indexterm>
	SUSE Linux implements individual control over each Samba daemon. A Samba control script that can be conveniently
	executed from the command line is shown in <link linkend="ch12SL"/>. This can be located in the directory
	<filename>/sbin</filename> in a file called <filename>samba</filename>. This type of control script should be
	owned by user root and group root, and set so that only root can execute it.
	</para>

      <para><indexterm>
	  <primary>startup script</primary>
	</indexterm>
	A sample startup script for a Red Hat Linux system is shown in <link linkend="ch12RHscript"/>.
	This file could be located in the directory <filename>/etc/rc.d</filename> and can be called
	<filename>samba</filename>. A similar startup script is required to control <command>winbind</command>.
	If you want to find more information regarding startup scripts please refer to the packaging section of
	the Samba source code distribution tarball. The packaging files for each platform include a
	startup control file.
	</para>

</sect1>

<sect1>
	<title>DNS Configuration Files</title>

	<para>
	The following files are common to all DNS server configurations. Rather than repeat them multiple times, they
	are presented here for general reference.
	</para>

	<sect2>
	<title>The Forward Zone File for the Loopback Adaptor</title>

	<para>
	The forward zone file for the loopback address never changes. An example file is shown
	in <link linkend="loopback"/>. All traffic destined for an IP address that is hosted on a
	physical interface on the machine itself is routed to the loopback adaptor. This is
	a fundamental design feature of the TCP/IP protocol implementation. The loopback adaptor
	is called <constant>localhost</constant>.
	</para>

<example id="loopback">
<title>DNS Localhost Forward Zone File: <filename>/var/lib/named/localhost.zone</filename></title>
<screen>
$TTL 1W
@		IN SOA	@   root (
				42		; serial
				2D		; refresh
				4H		; retry
				6W		; expiry
				1W )		; minimum

		IN NS		@
		IN A		127.0.0.1
</screen>
</example>

	</sect2>

	<sect2>
	<title>The Reverse Zone File for the Loopback Adaptor</title>

	<para>
	The reverse zone file for the loopback address as shown in <link linkend="dnsloopy"/>
	is necessary so that references to the address <constant>127.0.0.1</constant> can be
	resolved to the correct name of the interface. 
	</para>

<example id="dnsloopy">
<title>DNS Localhost Reverse Zone File: <filename>/var/lib/named/127.0.0.zone</filename></title>
<screen>
$TTL 1W
@		IN SOA		localhost.   root.localhost. (
				42		; serial
				2D		; refresh
				4H		; retry
				6W		; expiry
				1W )		; minimum

		IN NS		localhost.
1		IN PTR		localhost.
</screen>
</example>

<example id="roothint">
<title>DNS Root Name Server Hint File: <filename>/var/lib/named/root.hint</filename></title>
<screen>
; This file is made available by InterNIC under anonymous FTP as
;       file                /domain/named.root
;       on server           FTP.INTERNIC.NET
; last update: Nov 5, 2002. Related version of root zone: 2002110501
; formerly NS.INTERNIC.NET
.                        3600000  IN  NS    A.ROOT-SERVERS.NET.
A.ROOT-SERVERS.NET.      3600000      A     198.41.0.4
; formerly NS1.ISI.EDU
.                        3600000      NS    B.ROOT-SERVERS.NET.
B.ROOT-SERVERS.NET.      3600000      A     128.9.0.107
; formerly C.PSI.NET
.                        3600000      NS    C.ROOT-SERVERS.NET.
C.ROOT-SERVERS.NET.      3600000      A     192.33.4.12
; formerly TERP.UMD.EDU
.                        3600000      NS    D.ROOT-SERVERS.NET.
D.ROOT-SERVERS.NET.      3600000      A     128.8.10.90
; formerly NS.NASA.GOV
.                        3600000      NS    E.ROOT-SERVERS.NET.
E.ROOT-SERVERS.NET.      3600000      A     192.203.230.10
; formerly NS.ISC.ORG
.                        3600000      NS    F.ROOT-SERVERS.NET.
F.ROOT-SERVERS.NET.      3600000      A     192.5.5.241
; formerly NS.NIC.DDN.MIL
.                        3600000      NS    G.ROOT-SERVERS.NET.
G.ROOT-SERVERS.NET.      3600000      A     192.112.36.4
; formerly AOS.ARL.ARMY.MIL
.                        3600000      NS    H.ROOT-SERVERS.NET.
H.ROOT-SERVERS.NET.      3600000      A     128.63.2.53
; formerly NIC.NORDU.NET
.                        3600000      NS    I.ROOT-SERVERS.NET.
I.ROOT-SERVERS.NET.      3600000      A     192.36.148.17
; operated by VeriSign, Inc. 
.                        3600000      NS    J.ROOT-SERVERS.NET.
J.ROOT-SERVERS.NET.      3600000      A     192.58.128.30
; housed in LINX, operated by RIPE NCC
.                        3600000      NS    K.ROOT-SERVERS.NET.
K.ROOT-SERVERS.NET.      3600000      A     193.0.14.129 
; operated by IANA
.                        3600000      NS    L.ROOT-SERVERS.NET.
L.ROOT-SERVERS.NET.      3600000      A     198.32.64.12
; housed in Japan, operated by WIDE
.                        3600000      NS    M.ROOT-SERVERS.NET.
M.ROOT-SERVERS.NET.      3600000      A     202.12.27.33
; End of File
</screen>
</example>
	</sect2>

	<sect2>
	<title>DNS Root Server Hint File</title>

	<para>
	The content of the root hints file as shown in <link linkend="roothint"/>  changes slowly over time. 
	Periodically this file should be updated from the source shown. Because
	  of its size, this file is located at the end of this appendix.
	</para>

	</sect2>

</sect1>

<sect1 id="altldapcfg">
	<title>Alternative LDAP Database Initialization</title>

      <para><indexterm>
	  <primary>LDAP</primary>
	  <secondary>database</secondary>
	</indexterm><indexterm>
	  <primary>LDAP</primary>
	  <secondary>initial configuration</secondary>
	</indexterm>
	The following procedure may be used as an alternative means of configuring
	the initial LDAP database. Many administrators prefer to have greater control
	over how system files get configured.
	</para>

	<sect2>
	<title>Initialization of the LDAP Database</title>

	<para><indexterm>
	    <primary>LDIF</primary>
	  </indexterm><indexterm>
	    <primary>Domain Groups</primary>
	    <secondary>well-known</secondary>
	  </indexterm><indexterm>
	    <primary>SID</primary>
	  </indexterm>
	The first step to get the LDAP server ready for action is to create the LDIF file from
	which the LDAP database will be preloaded. This is necessary to create the containers
	into which the user, group, and other accounts are written. It is also necessary to
	preload the well-known Windows NT Domain Groups, as they must have the correct SID so
	that they can be recognized as special NT Groups by the MS Windows clients.
	</para>

	<procedure id="ldapinit">
	<title>LDAP Directory Pre-Load Steps</title>

		<step><para>
		Create a directory in which to store the files you use to generate
		the LDAP LDIF file for your system. Execute the following:
<screen>
&rootprompt; mkdir /etc/openldap/SambaInit
&rootprompt; chown root:root /etc/openldap/SambaInit
&rootprompt; chmod 700 /etc/openldap/SambaInit
</screen>
		</para></step>

		<step><para>
		Install the files shown in <link linkend="sbehap-ldapreconfa"/>, <link linkend="sbehap-ldapreconfb"/>,
		and <link linkend="sbehap-ldapreconfc"/> into the directory 
		<filename>/etc/openldap/SambaInit/SMBLDAP-ldif-preconfig.sh.</filename> These three files are,
		respectively, parts A, B, and C of the <filename>SMBLDAP-ldif-preconfig.sh</filename> file.
		</para></step>

		<step><para>
		Install the files shown in <link linkend="sbehap-ldifpata"/> and <link linkend="sbehap-ldifpatb"/> into the directory
		<filename>/etc/openldap/SambaInit/nit-ldif.pat.</filename> These two files are
                parts A and B, respectively, of the <filename>init-ldif.pat</filename> file.
		</para></step>

		<step><para>
		Change to the <filename>/etc/openldap/SambaInit</filename> directory. Execute the following:
<screen>
&rootprompt; ./SMBLDAP-ldif-preconfig.sh

How do you wish to refer to your organization?
Suggestions:
        Black Tire Company, Inc.
        Cat With Hat Ltd.
How would you like your organization name to appear?
Your organization name is: My Organization
Enter a new name is this is not what you want, press Enter to Continue.
Name [My Organization]: Abmas Inc.

Samba Config File Location [/etc/samba/smb.conf]:
Enter a new full path or press Enter to continue.
Samba Config File Location [/etc/samba/smb.conf]:
Domain Name: MEGANET2
Domain SID: S-1-5-21-3504140859-1010554828-2431957765

The name of your Internet domain is now needed in a special format
as follows, if your domain name is mydomain.org, what we need is
the information in the form of:
        Domain ID: mydomain
        Top level: org
If your fully qualified hostname is: snoopy.bazaar.garagesale.net
where "snoopy" is the name of the machine,
Then the information needed is:
        Domain ID: garagesale
        Top Level: net

Found the following domain name: abmas.biz
I think the bit we are looking for might be: abmas
Enter the domain name or press Enter to continue:

The top level organization name I will use is: biz
Enter the top level org name or press Enter to continue:
&rootprompt;
</screen>
		This creates a file called <filename>MEGANET2.ldif</filename>.
		</para></step>

		<step><para>
		It is now time to preload the LDAP database with the following
		command:
<screen>
&rootprompt; slapadd -v -l MEGANET2.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=Domains,dc=abmas,dc=biz" (00000006)
added: "sambaDomainName=MEGANET2,ou=Domains,dc=abmas,dc=biz" (00000007)
added: "cn=domadmins,ou=Groups,dc=abmas,dc=biz" (00000008)
added: "cn=domguests,ou=Groups,dc=abmas,dc=biz" (00000009)
added: "cn=domusers,ou=Groups,dc=abmas,dc=biz" (0000000a)
</screen>
		You should verify that the account information was correctly loaded by executing:
<screen>
&rootprompt; slapcat
dn: dc=abmas,dc=biz
objectClass: dcObject
objectClass: organization
dc: abmas
o: Abmas Inc.
description: Posix and Samba LDAP Identity Database
structuralObjectClass: organization
entryUUID: af552f8e-c4a1-1027-9002-9421e01bf474
creatorsName: cn=manager,dc=abmas,dc=biz
modifiersName: cn=manager,dc=abmas,dc=biz
createTimestamp: 20031217055747Z
modifyTimestamp: 20031217055747Z
entryCSN: 2003121705:57:47Z#0x0001#0#0000
...

dn: cn=domusers,ou=Groups,dc=abmas,dc=biz
objectClass: posixGroup
objectClass: sambaGroupMapping
gidNumber: 513
cn: domusers
sambaSID: S-1-5-21-3504140859-1010554828-2431957765-513
sambaGroupType: 2
displayName: Domain Users
description: Domain Users
structuralObjectClass: posixGroup
entryUUID: af7e98ba-c4a1-1027-900b-9421e01bf474
creatorsName: cn=manager,dc=abmas,dc=biz
modifiersName: cn=manager,dc=abmas,dc=biz
createTimestamp: 20031217055747Z
modifyTimestamp: 20031217055747Z
entryCSN: 2003121705:57:47Z#0x000a#0#0000
</screen>
		</para></step>

		<step><para>
		Your LDAP database is ready for testing. You can now start the LDAP server
		using the system tool for your Linux operating system. For SUSE Linux, you can
		do this as follows:
<screen>
&rootprompt; rcldap start
</screen>
		</para></step>

		<step><para>
		It is now a good idea to validate that the LDAP server is running correctly.
		Execute the following:
<screen>
&rootprompt; ldapsearch -x -b "dc=abmas,dc=biz" "(ObjectClass=*)"
# extended LDIF
#
# LDAPv3
# base &lt;dc=abmas,dc=biz&gt; with scope sub
# filter: (ObjectClass=*)
# requesting: ALL
#

# abmas.biz
dn: dc=abmas,dc=biz
objectClass: dcObject
objectClass: organization
dc: abmas
o: Abmas Inc.
description: Posix and Samba LDAP Identity Database
...
# domusers, Groups, abmas.biz
dn: cn=domusers,ou=Groups,dc=abmas,dc=biz
objectClass: posixGroup
objectClass: sambaGroupMapping
gidNumber: 513
cn: domusers
sambaSID: S-1-5-21-3504140859-1010554828-2431957765-513
sambaGroupType: 2
displayName: Domain Users
description: Domain Users

# search result
search: 2
result: 0 Success

# numResponses: 11
# numEntries: 10
</screen>
		Your LDAP server is ready for creation of additional accounts.
		</para></step>
	</procedure>

	</sect2>

<example id="sbehap-ldapreconfa">
<title>LDAP Pre-configuration Script: <filename>SMBLDAP-ldif-preconfig.sh</filename> &smbmdash; Part A</title>
<screen>
#!/bin/bash
#
# This script prepares the ldif LDAP load file only
#

# Pattern File Name
file=init-ldif.pat

# The name of my organization
ORGNAME="My Organization"

# My Internet domain. ie: if my domain is: buckets.org, INETDOMAIN="buckets"
INETDOMAIN="my-domain"

# In the above case, md domain is: buckets.org, TLDORG="org"
TLDORG="org"

# This is the Samba Domain/Workgroup Name
DOMNAME="MYWORKGROUP"

#
# Here We Go ...
#

cat &lt;&lt;EOF

How do you wish to refer to your organization?

Suggestions:
	Black Tire Company, Inc.
	Cat With Hat Ltd.

How would you like your organization name to appear?

EOF

echo "Your organization name is: $ORGNAME"
echo
echo "Enter a new name or, press Enter to Continue."
echo
</screen>
</example>

<example id="sbehap-ldapreconfb">
<title>LDAP Pre-configuration Script: <filename>SMBLDAP-ldif-preconfig.sh</filename> &smbmdash; Part B</title>
<screen>
echo -e -n "Name [$ORGNAME]: "
	read name

if [ ! -z "$name" ]; then 
	ORGNAME=${name}
fi
echo
sed "s/ORGNAME/${ORGNAME}/g" &lt; $file &gt; $file.tmp1

# Try to find smb.conf

if [ -e /usr/local/samba/lib/smb.conf ]; then
	CONF=/usr/local/samba/lib/smb.conf
elif [ -e /etc/samba/smb.conf ]; then
	CONF=/etc/samba/smb.conf
fi

echo "Samba Config File Location [$CONF]: "
echo
echo "Enter a new full path or press Enter to continue."
echo
echo -n "Samba Config File Location [$CONF]: "
	read name
if [ ! -z "$name" ]; then
	CONF=$name
fi
echo

# Find the name of our Domain/Workgroup
DOMNAME=`grep -i workgroup ${CONF} | sed "s/ //g" | cut -f2 -d=`
echo Domain Name: $DOMNAME
echo

sed "s/DOMNAME/${DOMNAME}/g" &lt; $file.tmp1 &gt; $file.tmp2

DOMSID=`net getlocalsid ${DOMNAME} | cut -f2 -d: | sed "s/ //g"`
echo Domain SID: $DOMSID

sed "s/DOMSID/${DOMSID}/g" &lt; $file.tmp2 &gt; $file.tmp1
</screen>
</example>

<example id="sbehap-ldapreconfc">
<title>LDAP Pre-configuration Script: <filename>SMBLDAP-ldif-preconfig.sh</filename> &smbmdash; Part C</title>
<screen>
cat &gt;&gt;EOL
The name of your Internet domain is now needed in a special format
as follows, if your domain name is mydomain.org, what we need is
the information in the form of:
	Domain ID: mydomain
	Top level: org

If your fully qualified hostname is: snoopy.bazaar.garagesale.net
where "snoopy" is the name of the machine,
Then the information needed is:
	Domain ID: garagesale
	Top Level: net

EOL
INETDOMAIN=`hostname -d | cut -f1 -d.`
echo Found the following domain name: `hostname -d`
echo "I think the bit we are looking for might be: $INETDOMAIN"
echo
echo -n "Enter the domain name or press Enter to continue: "
	read domnam
if [ ! -z $domnam ]; then
	INETDOMAIN=$domnam
fi
echo
sed "s/INETDOMAIN/${INETDOMAIN}/g" &lt; $file.tmp1 &gt; $file.tmp2
TLDORG=`hostname -d | sed "s/${INETDOMAIN}.//g"`
echo "The top level organization name I will use is: ${TLDORG}"
echo
echo -n "Enter the top level org name or press Enter to continue: "
	read domnam
if [ ! -z $domnam ]; then
        TLDORG=$domnam
fi
sed "s/TLDORG/${TLDORG}/g" &lt; $file.tmp2 &gt; $DOMNAME.ldif
rm $file.tmp*
exit 0
</screen>
</example>

<example id="sbehap-ldifpata">
<title>LDIF Pattern File Used to Pre-configure LDAP &smbmdash; Part A</title>
<screen>
dn: dc=INETDOMAIN,dc=TLDORG
objectClass: dcObject
objectClass: organization
dc: INETDOMAIN
o: ORGNAME
description: Posix and Samba LDAP Identity Database

dn: cn=Manager,dc=INETDOMAIN,dc=TLDORG
objectClass: organizationalRole
cn: Manager
description: Directory Manager

dn: ou=People,dc=INETDOMAIN,dc=TLDORG
objectClass: top
objectClass: organizationalUnit
ou: People

dn: ou=Computers,dc=INETDOMAIN,dc=TLDORG
objectClass: top
objectClass: organizationalUnit
ou: Computers

dn: ou=Groups,dc=INETDOMAIN,dc=TLDORG
objectClass: top
objectClass: organizationalUnit
ou: Groups

dn: ou=Idmap,dc=INETDOMAIN,dc=TLDORG
objectClass: top
objectClass: organizationalUnit
ou: Idmap

dn: sambaDomainName=DOMNAME,ou=Domains,dc=INETDOMAIN,dc=TLDORG
objectClass: sambaDomain
sambaDomainName: DOMNAME
sambaSID: DOMSID
sambaAlgorithmicRidBase: 1000
structuralObjectClass: sambaDomain
</screen>
</example>

<example id="sbehap-ldifpatb">
<title>LDIF Pattern File Used to Pre-configure LDAP &smbmdash; Part B</title>
<screen>
dn: cn=domadmins,ou=Groups,dc=INETDOMAIN,dc=TLDORG
objectClass: posixGroup
objectClass: sambaGroupMapping
gidNumber: 512
cn: domadmins
sambaSID: DOMSID-512
sambaGroupType: 2
displayName: Domain Admins
description: Domain Administrators

dn: cn=domguests,ou=Groups,dc=INETDOMAIN,dc=TLDORG
objectClass: posixGroup
objectClass: sambaGroupMapping
gidNumber: 514
cn: domguests
sambaSID: DOMSID-514
sambaGroupType: 2
displayName: Domain Guests
description: Domain Guests Users

dn: cn=domusers,ou=Groups,dc=INETDOMAIN,dc=TLDORG
objectClass: posixGroup
objectClass: sambaGroupMapping
gidNumber: 513
cn: domusers
sambaSID: DOMSID-513
sambaGroupType: 2
displayName: Domain Users
description: Domain Users
</screen>
</example>

</sect1>

<sect1>
<title>The LDAP Account Manager</title>

<para>
<indexterm><primary>LAM</primary></indexterm>
<indexterm><primary>LDAP Account Manager</primary><see>LAM</see></indexterm>
<indexterm><primary>PHP</primary></indexterm>
<indexterm><primary>unencrypted</primary></indexterm>
<indexterm><primary>SSL</primary></indexterm>
<indexterm><primary>Posix</primary></indexterm>
<indexterm><primary>accounts</primary><secondary>manage</secondary></indexterm>
The LDAP Account Manager (LAM) is an application suite that has been written in PHP.
LAM can be used with any Web server that has PHP4 support. It connects to the LDAP
server either using unencrypted connections or via SSL/TLS. LAM can be used to manage
Posix accounts as well as SambaSAMAccounts for users, groups, and Windows machines
(hosts).
</para>

<para>
LAM is available from the <ulink url="http://sourceforge.net/projects/lam/">LAM</ulink>
home page and from its mirror sites. LAM has been released under the GNU GPL version 2.
The current version of LAM is 0.4.9. Release of version 0.5 is expected in the third quarter
of 2005.
</para>

<para>
<indexterm><primary>PHP4</primary></indexterm>
<indexterm><primary>OpenLDAP</primary></indexterm>
<indexterm><primary>Perl</primary></indexterm>
Requirements:
</para>

<itemizedlist>
	<listitem><para>A web server that will work with PHP4.</para></listitem>
	<listitem><para>PHP4 (available from the <ulink url="http://www.php.net/">PHP</ulink> home page.)</para></listitem>
	<listitem><para>OpenLDAP 2.0 or later.</para></listitem>
	<listitem><para>A Web browser that supports CSS.</para></listitem>
	<listitem><para>Perl.</para></listitem>
	<listitem><para>The gettext package.</para></listitem>
	<listitem><para>mcrypt + mhash (optional).</para></listitem>
	<listitem><para>It is also a good idea to install SSL support.</para></listitem>
</itemizedlist>

<para>
LAM is a useful tool that provides a simple Web-based device that can be used to
manage the contents of the LDAP directory to:
<indexterm><primary>organizational units</primary></indexterm>
<indexterm><primary>operating profiles</primary></indexterm>
<indexterm><primary>account policies</primary></indexterm>
</para>

<itemizedlist>
	<listitem><para>Display user/group/host and Domain entries.</para></listitem>
	<listitem><para>Manage entries (Add/Delete/Edit).</para></listitem>
	<listitem><para>Filter and sort entries.</para></listitem>
	<listitem><para>Store and use multiple operating profiles.</para></listitem>
	<listitem><para>Edit organizational units (OUs).</para></listitem>
	<listitem><para>Upload accounts from a file.</para></listitem>
	<listitem><para>Is compatible with Samba-2.2.x and Samba-3.</para></listitem>
</itemizedlist>

<para>
When correctly configured, LAM allows convenient management of UNIX (Posix) and Samba
user, group, and windows domain member machine accounts.
</para>

<para>
<indexterm><primary>default password</primary></indexterm>
<indexterm><primary>secure connections</primary></indexterm>
<indexterm><primary>LAM</primary></indexterm>
<indexterm><primary>SSL</primary></indexterm>
The default password is <quote>lam.</quote> It is highly recommended that you use only 
an SSL connection to your Web server for all remote operations involving LAM. If you 
want secure connections, you must configure your Apache Web server to permit connections 
to LAM using only SSL.
</para>

<procedure id="sbehap-laminst">
<title>Apache Configuration Steps for LAM</title>

	<step><para>
	Extract the LAM package by untarring it as shown here:
<screen>
&rootprompt; tar xzf ldap-account-manager_0.4.9.tar.gz
</screen>
	Alternatively, install the LAM DEB for your system using the following command:
<screen>
&rootprompt; dpkg -i ldap-account-manager_0.4.9.all.deb
</screen>
	</para></step>
	
	<step><para>
	Copy the extracted files to the document root directory of your Web server.
	For example, on SUSE Linux Enterprise Server 9, copy to the 
	<filename>/srv/www/htdocs</filename> directory.
	</para></step>

	<step><para>
	<indexterm><primary>file permissions</primary></indexterm>
	Set file permissions using the following commands:
<screen>
&rootprompt; chown -R wwwrun:www /srv/www/htdocs/lam
&rootprompt; chmod 755 /srv/www/htdocs/lam/sess
&rootprompt; chmod 755 /srv/www/htdocs/lam/tmp
&rootprompt; chmod 755 /srv/www/htdocs/lam/config
&rootprompt; chmod 755 /srv/www/htdocs/lam/lib/*pl
</screen>
	</para></step>

	<step><para>
	<indexterm><primary>LAM</primary><secondary>configuration file</secondary></indexterm>
       Using your favorite editor create the following <filename>config.cfg</filename>
       LAM configuration file:
<screen>
&rootprompt; cd /srv/www/htdocs/lam/config
&rootprompt; cp config.cfg_sample config.cfg
&rootprompt; vi config.cfg
</screen>
	<indexterm><primary>LAM</primary><secondary>profile</secondary></indexterm>
	<indexterm><primary>LAM</primary><secondary>wizard</secondary></indexterm>
	An example file is shown in <link linkend="lamcfg"/>.
	This is the minimum configuration that must be completed. The LAM profile
	file can be created using a convenient wizard that is part of the LAM
	configuration suite.
	</para></step>

	<step><para>
	Start your Web server then, using your Web browser, connect to 
	<ulink url="http://localhost/lam">LAM</ulink> URL. Click on the
	the <parameter>Configuration Login</parameter> link then click on the
	Configuration Wizard link to begin creation of the default profile so that 
	LAM can connect to your LDAP server. Alternately, copy the 
	<filename>lam.conf_sample</filename> file to a file called 
	<filename>lam.conf</filename> then, using your favorite editor, 
	change the settings to match local site needs.
	</para></step>
</procedure>

	<para>
	<indexterm><primary>pitfalls</primary></indexterm>
	An example of a working file is shown here in <link linkend="lamconf"/>.
	This file has been stripped of comments to keep the size small. The comments
	and help information provided in the profile file that the wizard creates
	is very useful and will help many administrators to avoid pitfalls.
	Your configuration file obviously reflects the configuration options that
	are preferred at your site.
	</para>

	<para>
	<indexterm><primary>LAM</primary><secondary>login screen</secondary></indexterm>
	It is important that your LDAP server is running at the time that LAM is 
	being configured. This permits you to validate correct operation.
	An example of the LAM login screen is provided in <link linkend="lam-login"/>.
	</para>

	<figure id="lam-login">
		<title>The LDAP Account Manager Login Screen</title>
		<imagefile scale="50">lam-login</imagefile>
	</figure>

	<para>
	<indexterm><primary>LAM</primary><secondary>configuration editor</secondary></indexterm>
	The LAM configuration editor has a number of options that must be managed correctly.
	An example of use of the LAM configuration editor is shown in <link linkend="lam-config"/>.
	It is important that you correctly set the minimum and maximum UID/GID values that are
	permitted for use at your site. The default values may not be compatible with a need to
	modify initial default account values for well-known Windows network users and groups.
	The best work-around is to temporarily set the minimum values to zero (0) to permit
	the initial settings to be made. Do not forget to reset these to sensible values before
	using LAM to add additional users and groups.
	</para>

	<figure id="lam-config">
		<title>The LDAP Account Manager Configuration Screen</title>
		<imagefile scale="50">lam-config</imagefile>
	</figure>

	<para>
	<indexterm><primary>PDF</primary></indexterm>
	LAM has some nice, but unusual features. For example, one unexpected feature in most application
	screens permits the generation of a PDF file that lists configuration information. This is a well
	thought out facility. This option has been edited out of the following screen shots to conserve
	space.
	</para>

	<para>
	<indexterm><primary>LAM</primary><secondary>opening screen</secondary></indexterm>
	When you log onto LAM the opening screen drops you right into the user manager as shown in
	<link linkend="lam-user"/>. This is a logical action as it permits the most-needed facility
	to be used immediately. The editing of an existing user, as with the addition of a new user,
	is easy to follow and very clear in both layout and intent. It is a simple matter to edit
	generic settings, UNIX specific parameters, and then Samba account requirements. Each step
	involves clicking a button that intuitively drives you through the process. When you have
	finished editing simply press the <guimenu>Final</guimenu> button.
	</para>

	<figure id="lam-user">
		<title>The LDAP Account Manager User Edit Screen</title>
		<imagefile scale="50">lam-users</imagefile>
	</figure>

	<para>
	The edit screen for groups is shown in <link linkend="lam-group"/>. As with the edit screen
	for user accounts, group accounts may be rapidly dealt with. <link linkend="lam-group-mem"/>
	shows a sub-screen from the group editor that permits users to be assigned secondary group
	memberships. 
	</para>

	<figure id="lam-group">
		<title>The LDAP Account Manager Group Edit Screen</title>
		<imagefile scale="50">lam-groups</imagefile>
	</figure>

	<figure id="lam-group-mem">
		<title>The LDAP Account Manager Group Membership Edit Screen</title>
		<imagefile scale="50">lam-group-members</imagefile>
	</figure>

	<para>
	<indexterm><primary>smbldap-tools</primary></indexterm><indexterm><primary>scripts</primary></indexterm>
	The final screen presented here is one that you should not normally need to use. Host accounts will
	be automatically managed using the smbldap-tools scripts. This means that the screen <link linkend="lam-host"/>
	will, in most cases, not be used.
	</para>

	<figure id="lam-host">
		<title>The LDAP Account Manager Host Edit Screen</title>
		<imagefile scale="50">lam-hosts</imagefile>
	</figure>

	<para>
	One aspect of LAM that may annoy some users is the way it forces certain conventions on
	the administrator. For example, LAM does not permit the creation of Windows user and group
	accounts that contain spaces even though the underlying UNIX/Linux
	operating system may exhibit no problems with them. Given the propensity for using upper-case
	characters and spaces (particularly in the default Windows account names) this may cause
	some annoyance. For the rest, LAM is a very useful administrative tool.
	</para>
	
	<para>
	The next major release, LAM 0.5, will have fewer restrictions and support the latest Samba features
	(e.g., logon hours). The new plugin-based architecture also allows management of much more different
	account types like plain UNIX accounts. The upload can now handle groups and hosts, too. Another
	important point is the tree view which allows browsing and editing LDAP objects directly.
	</para>

<example id="lamcfg">
<title>Example LAM Configuration File &smbmdash; <filename>config.cfg</filename></title>
<screen>
# password to add/delete/rename configuration profiles
password: not24get

# default profile, without ".conf"
default: lam
</screen>
</example>

<example id="lamconf">
<title>LAM Profile Control File &smbmdash; <filename>lam.conf</filename></title>
<screen>
ServerURL: ldap://massive.abmas.org:389
Admins: cn=Manager,dc=abmas,dc=biz
Passwd: not24get
usersuffix: ou=People,dc=abmas,dc=biz
groupsuffix: ou=Groups,dc=abmas,dc=biz
hostsuffix: ou=Computers,dc=abmas,dc=biz
domainsuffix: ou=Domains,dc=abmas,dc=biz
MinUID: 0
MaxUID: 65535
MinGID: 0
MaxGID: 65535
MinMachine: 20000
MaxMachine: 25000
userlistAttributes: #uid;#givenName;#sn;#uidNumber;#gidNumber
grouplistAttributes: #cn;#gidNumber;#memberUID;#description
hostlistAttributes: #cn;#description;#uidNumber;#gidNumber
maxlistentries: 30
defaultLanguage: en_GB:ISO-8859-1:English (Great Britain)
scriptPath: 
scriptServer: 
samba3: yes
cachetimeout: 5
pwdhash: SSHA
</screen>
</example>

</sect1>

<sect1 id="ch12-SUIDSGID">
	<title>Effect of Setting File and Directory SUID/SGID Permissions Explained</title>

	<indexterm><primary>SUID</primary></indexterm>
	<indexterm><primary>SGID</primary></indexterm>
	<para>
	The setting of the SUID/SGID bits on the file or directory permissions flag has particular
	consequences. If the file is executable and the SUID bit is set, it executes with the privilege
	of (with the UID of) the owner of the file. For example, if you are logged onto a system as
	a normal user (let's say as the user <constant>bobj</constant>), and you execute a file that is owned
	by the user <constant>root</constant> (uid = 0), and the file has the SUID bit set, then the file is
	executed as if you had logged in as the user <constant>root</constant> and then executed the file.
	The SUID bit effectively gives you (as <constant>bobj</constant>) administrative privilege for the
	use of that executable file.
	</para>

	<para>
	The setting of the SGID bit does precisely the same as the effect of the SUID bit, except that it
	applies the privilege to the UNIX group setting. In other words, the file executes with the force
	of capability of the group.
	</para>

	<para>
	When the SUID/SGID permissions are set on a directory, all files that are created within that directory
	are automatically given the ownership of the SUID user and the SGID group, as per the ownership
	of the directory in which the file is created. This means that the system level <command>create()</command>
	function executes with the SUID user and/or SGID group of the directory in which the file is
	created.
	</para>

	<para>
	If you want to obtain the SUID behavior, simply execute the following command:
<screen>
&rootprompt; chmod u+s file-or-directory
</screen>
	To set the SGID properties on a file or a directory, execute this command:
<screen>
&rootprompt; chmod g+s file-or-directory
</screen>
	And to set both SUID and SGID properties, execute the following:
<screen>
&rootprompt; chmod ug+s file-or-directory
</screen>
	</para>

	<para>
	Let's consider the example of a directory <filename>/data/accounts</filename>. The permissions on this
	directory before setting both SUID and SGID on this directory are:
<screen>
&rootprompt; ls -al /data/accounts
total 1
drwxr-xr-x   10 root     root          232 Dec 18 17:08 .
drwxr-xr-x   21 root     root          600 Dec 17 23:15 ..
drwxrwxrwx    2 bobj     Domain Users  48 Dec 18 17:08 accounts/
drwx------    2 root     root           48 Jan 26  2002 lost+found
</screen>
	In this example, if the user <constant>maryv</constant> creates a file, it is owned by her.
	If <constant>maryv</constant> has the primary group of <constant>Accounts</constant>, the file is
	owned by the group <constant>Accounts</constant>, as shown in this listing:
<screen>
&rootprompt; ls -al /data/accounts/maryvfile.txt
drw-rw-r--    2 maryv    Accounts     12346 Dec 18 17:53
</screen>
	</para>

	<para>
	Now you set the SUID and SGID and check the result as follows:
<screen>
&rootprompt; chmod ug+s /data/accounts
&rootprompt; ls -al /data/accounts
total 1
drwxr-xr-x   10 root     root          232 Dec 18 17:08 .
drwxr-xr-x   21 root     root          600 Dec 17 23:15 ..
drwsrwsr-x    2 bobj     Domain Users  48 Dec 18 17:08 accounts
drwx------    2 root     root           48 Jan 26  2002 lost+found
</screen>
	If <constant>maryv</constant> creates a file in this directory after this change has been made, the
	file is owned by the user <constant>bobj</constant>, and the group is set to the group
	<constant>Domain Users</constant>, as shown here:
<screen>
&rootprompt; chmod ug+s /data/accounts
&rootprompt; ls -al /data/accounts/maryvfile.txt
total 1
drw-rw-r--    2 bobj     Domain Users  12346 Dec 18 18:11 maryvfile.txt
</screen>
	</para>

</sect1>

<sect1 id="ch12dblck">
	<title>Shared Data Integrity</title>

      <para><indexterm>
	  <primary>data integrity</primary>
	</indexterm><indexterm>
	  <primary>multi-user</primary>
	  <secondary>data access</secondary>
	</indexterm>
	The integrity of shared data is often viewed as a particularly emotional issue, especially where
	there are concurrent problems with multiuser data access. Contrary to the assertions of some who have
	experienced problems in either area, the cause has nothing to do with the phases of the moons of Jupiter.
	</para>

	<para>
	The solution to concurrent multiuser data access problems must consider three separate areas
	from which the problem may stem:<indexterm>
	  <primary>locking</primary>
	  <secondary>Application level</secondary>
	</indexterm><indexterm>
	  <primary>locking</primary>
	  <secondary>Client side</secondary>
	</indexterm><indexterm>
	  <primary>locking</primary>
	  <secondary>Server side</secondary>
	</indexterm>
	</para>

	<itemizedlist>
		<listitem><para>application-level locking controls</para></listitem>
		<listitem><para>client-side locking controls</para></listitem>
		<listitem><para>server-side locking controls</para></listitem>
	</itemizedlist>

      <para><indexterm>
	  <primary>database applications</primary>
	</indexterm><indexterm>
	  <primary>Microsoft Access</primary>
	</indexterm>
	Many database applications use some form of application-level access control. An example of one
	well-known application that uses application-level locking is Microsoft Access. Detailed guidance
	is provided here because this is the most common application for which problems have been reported.
	</para>

      <para><indexterm>
	  <primary>Microsoft Excel</primary>
	</indexterm><indexterm>
	  <primary>Act!</primary>
	</indexterm>
	Common applications that are affected by client- and server-side locking controls include MS
	Excel and Act!. Important locking guidance is provided here.
	</para>


	<sect2>
	<title>Microsoft Access</title>

	<para>
	The best advice that can be given is to carefully read the Microsoft knowledgebase articles that
	cover this area. Examples of relevant documents include:
	</para>

	<itemizedlist>
	<listitem><para>http://support.microsoft.com/default.aspx?scid=kb;en-us;208778</para></listitem>
	<listitem><para>http://support.microsoft.com/default.aspx?scid=kb;en-us;299373</para></listitem>
	</itemizedlist>


	<para><indexterm>
	    <primary>multi-user</primary>
	    <secondary>access</secondary>
	  </indexterm><indexterm>
	    <primary>exclusive open</primary>
	  </indexterm>
	Make sure that your MS Access database file is configured for multiuser access (not set for 
	exclusive open). Open MS Access on each client workstation, then set the following: <menuchoice>
	<guimenu>(Menu bar) Tools</guimenu><guimenu>Options</guimenu><guimenu>[tab] General</guimenu>
	</menuchoice>.  Set network path to Default database folder: <filename>\\server\share\folder</filename>.
	</para>

	<para>
        You can configure MS Access file sharing behavior as follows: click <guimenu>[tab] Advanced</guimenu>.
	  Set:<indexterm>
	    <primary>record locking</primary>
	  </indexterm>
	</para>

	<itemizedlist>
                <listitem><para>Default open mode: Shared</para></listitem>
                <listitem><para>Default Record Locking: Edited Record</para></listitem>
                <listitem><para>Open databases using record_level locking</para></listitem>
	</itemizedlist>

	<para><indexterm>
	    <primary>MS Access</primary>
	    <secondary>validate</secondary>
	  </indexterm>
        You must now commit the changes so that they will take effect. To do so, click 
	<guimenu>Apply</guimenu><guimenu>Ok</guimenu>. At this point, you should exit MS Access, restart 
	it, and then validate that these settings have not changed.
	</para>

	</sect2>

	<sect2>
	<title>Act! Database Sharing</title>

	<para><indexterm>
	    <primary>ACT! database</primary>
	  </indexterm><indexterm>
	    <primary>data corruption</primary>
	  </indexterm>
	Where the server sharing the ACT! database(s) is running Samba,or Windows NT, 200x, or XP, you 
	must disable opportunistic locking on the server and all workstations. Failure to do so
	results in data corruption. This information is available from the Act! Web site
	knowledgebase articles 
	<ulink url="http://itdomino.saleslogix.com/act.nsf/docid/1998223162925">1998223162925</ulink>
	as well as from article
	<ulink url="http://itdomino.saleslogix.com/act.nsf/docid/200110485036">200110485036</ulink>.
	</para>

	<para><indexterm>
	    <primary>opportunistic locking</primary>
	  </indexterm><indexterm>
	    <primary>Act!Diag</primary>
	  </indexterm>
	These documents clearly state that opportunistic locking must be disabled on both
	the server (Samba in the case we are interested in here), as well as on every workstation
	from which the centrally shared Act! database will be accessed. Act! provides
	a tool called <command>Act!Diag</command> that may be used to disable all workstation
	registry settings that may otherwise interfere with the operation of Act! 
	Registered Act! users may download this utility from the Act! Web 
	<ulink url="http://www.act.com/support/updates/index.cfm">site.</ulink>
	</para>

	</sect2>

	<sect2>
	<title>Opportunistic Locking Controls</title>

	<para><indexterm>
	    <primary>file caching</primary>
	  </indexterm>
	Third-party Windows applications may not be compatible with the use of opportunistic file
	and record locking. For applications that are known not to be compatible,<footnote>Refer to
	the application manufacturer's installation guidelines and knowledge base for specific
	information regarding compatibility. It is often safe to assume that if the software
	manufacturer does not specifically mention incompatibilities with opportunistic file
	and record locking, or with Windows client file caching, the application is probably
	compatible with Windows (as well as Samba) default settings.</footnote> oplock
	support may need to be disabled both on the Samba server and on the Windows workstations.
	</para>

	<para><indexterm>
	    <primary>cache</primary>
	  </indexterm><indexterm>
	    <primary>write lock</primary>
	  </indexterm><indexterm>
	    <primary>flush</primary>
	    <secondary>cache memory</secondary>
	  </indexterm>
	Oplocks enable a Windows client to cache parts of a file that are being
	edited. Another windows client may then request to open the file with the
	ability to write to it. The server will then ask the original workstation
	that had the file open with a write lock to release its lock. Before
	doing so, that workstation must flush the file from cache memory to the
	disk or network drive.
	</para>

	<para><indexterm>
	    <primary>Oplocks</primary>
	    <secondary>disabled</secondary>
	  </indexterm>
	Disabling of Oplocks usage may require server and client changes.
	Oplocks may be disabled by file, by file pattern, on the share, or on the
	Samba server.
	</para>

	<para>
	The following are examples showing how Oplock support may be managed using
	Samba &smb.conf; file settings:
<screen>
By file:        veto oplock files = myfile.mdb

By Pattern:     veto oplock files = /*.mdb/

On the Share:   oplocks = No
                level2 oplocks = No

On the server:
(in [global])   oplocks = No
                level2 oplocks = No
</screen>
	</para>

	<para>
	The following registry entries on Microsoft Windows XP Professional, 2000 Professional, and Windows NT4
	workstation clients must be configured as shown here:
<screen>
REGEDIT4

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
            Services\LanmanServer\Parameters]
      "EnableOplocks"=dword:00000000

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
            Services\LanmanWorkstation\Parameters]
      "UseOpportunisticLocking"=dword:00000000
</screen>
	</para>

	<para>
	Comprehensive coverage of file and record-locking controls is provided in TOSHARG, Chapter 13.
	The information in that chapter was obtained from a wide variety of sources.
	</para>

	</sect2>

</sect1>

</appendix>