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+<?xml version="1.0" encoding="iso-8859-1"?>
+<!DOCTYPE chapter PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
+<chapter id="Big500users">
+ <title>The 500-User Office</title>
+
+ <para>
+ The Samba-3 networking you explored in <link linkend="secure"/> covers the finer points of
+ configuration of peripheral services such as DHCP and DNS, and WINS. You experienced
+ implementation of a simple configuration of the services that are important adjuncts
+ to successful deployment of Samba.
+ </para>
+
+ <para>
+ An analysis of the history of postings to the Samba mailing list easily demonstrates
+ that the two most prevalent Samba problem areas are
+ </para>
+
+ <itemizedlist>
+ <listitem><para>
+ Defective resolution of a NetBIOS name to its IP address
+ </para></listitem>
+
+ <listitem><para>
+ Printing problems
+ </para></listitem>
+
+ </itemizedlist>
+
+ <para>
+ The exercises
+ so far in this book have focused on implementation of the simplest printing processes
+ involving no print job processing intelligence. In this chapter, you maintain
+ that same approach to printing, but <link linkend="happy"/> presents an opportunity
+ to make printing more complex for the administrator while making it easier for the user.
+ </para>
+
+ <para>
+ <indexterm><primary>WINS server</primary></indexterm>
+ <indexterm><primary>tdbsam</primary></indexterm>
+ <indexterm><primary>passdb backend</primary></indexterm>
+ <link linkend="secure"/> demonstrates operation of a DHCP server and a DNS server
+ as well as a central WINS server. You validated the operation of these services and
+ saw an effective implementation of a Samba domain controller using the
+ <parameter>tdbsam</parameter> passdb backend.
+ </para>
+
+ <para>
+ The objective of this chapter is to introduce more complex techniques that can be used to
+ improve manageability of Samba as networking needs grow. In this chapter, you implement
+ a distributed DHCP server environment, a distributed DNS server arrangement, a centralized
+ WINS server, and a centralized Samba domain controller.
+ </para>
+
+ <para>
+ A note of caution is important regarding the Samba configuration that is used in this
+ chapter. The use of a single domain controller on a routed, multisegment network is
+ a poor design choice that leads to potential network user complaints.
+ This chapter demonstrates some successful
+ techniques in deployment and configuration management. This should be viewed as a
+ foundation chapter for complex Samba deployments.
+ </para>
+
+ <para>
+ As you master the techniques presented here, you may find much better methods to
+ improve network management and control while reducing human resource overheads.
+ You should take the opportunity to innovate and expand on the methods presented
+ here and explore them to the fullest.
+ </para>
+
+<sect1>
+ <title>Introduction</title>
+
+ <para>
+ Business continues to go well for Abmas. Mr. Meany is driving your success and the
+ network continues to grow thanks to the hard work Christine has done. You recently
+ hired Stanley Soroka as manager of information systems. Christine recommended Stan
+ to the role. She told you Stan is so good at handling Samba that he can make a cast
+ iron rocking horse that is embedded in concrete kick like a horse at a rodeo. You
+ need skills like his. Christine and Stan get along just fine. Let's see what
+ you can get out of this pair as they plot the next-generation networks.
+ </para>
+
+ <para>
+ Ten months ago Abmas closed an acquisition of a property insurance business. The
+ founder lost interest in the business and decided to sell it to Mr. Meany. Because
+ they were former university classmates, the purchase was concluded with mutual assent.
+ The acquired business is located at the other end of town in much larger facilities.
+ The old Abmas building has become too small. Located on the same campus as the newly
+ acquired business are two empty buildings that are ideal to provide Abmas with
+ opportunity for growth.
+ </para>
+
+ <para>
+ Abmas has now completed the purchase of the two empty buildings, and you are
+ to install a new network and relocate staff in nicely furnished new facilities.
+ The new network is to be used to fully integrate company operations. You have
+ decided to locate the new network operations control center in the larger building
+ in which the insurance group is located to take advantage of an ideal floor space
+ and to allow Stan and Christine to fully stage the new network and test it before
+ it is rolled out. Your strategy is to complete the new network so that it
+ is ready for operation when the old office moves into the new premises.
+ </para>
+
+ <sect2>
+ <title>Assignment Tasks</title>
+
+ <para>
+ The acquired business had 280 network users. The old Abmas building housed
+ 220 network users in unbelievably cramped conditions. The network that
+ initially served 130 users now handles 220 users quite well.
+ </para>
+
+ <para>
+ The two businesses will be fully merged to create a single campus company.
+ The Property Insurance Group (PIG) houses 300 employees, the new Accounting
+ Services Group (ASG) will be in a small building (BLDG1) that houses 50
+ employees, and the Financial Services Group (FSG) will be housed in a large
+ building that has capacity for growth (BLDG2). Building 2 houses 150 network
+ users.
+ </para>
+
+ <para>
+ You have decided to connect the building using fiber optic links between new
+ routers. As a backup, the buildings are interconnected using line-of-sight
+ high-speed infrared facilities. The infrared connection provides a
+ secondary route to be used during periods of high demand for network
+ bandwidth.
+ </para>
+
+ <para>
+ The Internet gateway is upgraded to 15 Mb/sec service. Your ISP
+ provides on your premises a fully managed Cisco PIX firewall. You no longer need
+ to worry about firewall facilities on your network.
+ </para>
+
+ <para>
+ Stanley and Christine have purchased new server hardware. Christine wants to
+ roll out a network that has whistles and bells. Stan wants to start off with
+ a simple to manage, not-too-complex network. He believes that network
+ users need to be gradually introduced to new features and capabilities and not
+ rushed into an environment that may cause disorientation and loss of productivity.
+ </para>
+
+ <para>
+ Your intrepid network team has decided to implement a network configuration
+ that closely mirrors the successful system you installed in the old Abmas building.
+ The new network infrastructure is owned by Abmas, but all desktop systems
+ are being procured through a new out-source services and leasing company. Under
+ the terms of a deal with Mr. M. Proper (CEO), DirectPointe, Inc., provides
+ all desktop systems and includes full level-one help desk support for
+ a flat per-machine monthly fee. The deal allows you to add workstations on demand.
+ This frees Stan and Christine to deal with deeper issues as they emerge and
+ permits Stan to work on creating new future value-added services.
+ </para>
+
+ <para>
+ DirectPointe Inc. receives from you a new standard desktop configuration
+ every four months. They automatically roll that out to each desktop system.
+ You must keep DirectPointe informed of all changes.
+ </para>
+
+ <para><indexterm>
+ <primary>PDC</primary>
+ </indexterm>
+ The new network has a single Samba Primary Domain Controller (PDC) located in the
+ Network Operation Center (NOC). Buildings 1 and 2 each have a local server
+ for local application servicing. It is a domain member. The new system
+ uses the <parameter>tdbsam</parameter> passdb backend.
+ </para>
+
+ <para>
+ Printing is based on raw pass-through facilities just as it has been used so far.
+ All printer drivers are installed on the desktop and notebook computers.
+ </para>
+
+ </sect2>
+</sect1>
+
+<sect1>
+ <title>Dissection and Discussion</title>
+
+ <para>
+ <indexterm><primary>network load factors</primary></indexterm>
+ The example you are building in this chapter is of a network design that works, but this
+ does not make it a design that is recommended. As a general rule, there should be at least
+ one Backup Domain Controller (BDC) per 150 Windows network clients. The principle behind
+ this recommendation is that correct operation of MS Windows clients requires rapid
+ network response to all SMB/CIFS requests. The same rule says that if there are more than
+ 50 clients per domain controller, they are too busy to service requests. Let's put such
+ rules aside and recognize that network load affects the integrity of domain controller
+ responsiveness. This network will have 500 clients serviced by one central domain
+ controller. This is not a good omen for user satisfaction. You, of course, address this
+ very soon (see <link linkend="happy"/>).
+ </para>
+
+ <sect2>
+ <title>Technical Issues</title>
+
+ <para>
+ Stan has talked you into a horrible compromise, but it is addressed. Just make
+ certain that the performance of this network is well validated before going live.
+ </para>
+
+ <para>
+ Design decisions made in this design include the following:
+ </para>
+
+ <itemizedlist>
+ <listitem><para>
+ <indexterm><primary>PDC</primary></indexterm>
+ <indexterm><primary>LDAP</primary></indexterm>
+ <indexterm><primary>identity management</primary></indexterm>
+ A single PDC is being implemented. This limitation is based on the choice not to
+ use LDAP. Many network administrators fear using LDAP because of the perceived
+ complexity of implementation and management of an LDAP-based backend for all user
+ identity management as well as to store network access credentials.
+ </para></listitem>
+
+ <listitem><para>
+ <indexterm><primary>BDC</primary></indexterm>
+ <indexterm><primary>machine secret password</primary></indexterm>
+ Because of the refusal to use an LDAP (ldapsam) passdb backend at this time, the
+ only choice that makes sense with 500 users is to use the tdbsam passwd backend.
+ This type of backend is not receptive to replication to BDCs. If the tdbsam
+ <filename>passdb.tdb</filename> file is replicated to BDCs using
+ <command>rsync</command>, there are two potential problems: (1) data that is in
+ memory but not yet written to disk will not be replicated, and (2) domain member
+ machines periodically change the secret machine password. When this happens, there
+ is no mechanism to return the changed password to the PDC.
+ </para></listitem>
+
+ <listitem><para>
+ All domain user, group, and machine accounts are managed on the PDC. This makes
+ for a simple mode of operation but has to be balanced with network performance and
+ integrity of operations considerations.
+ </para></listitem>
+
+ <listitem><para>
+ <indexterm><primary>WINS</primary></indexterm>
+ A single central WINS server is being used. The PDC is also the WINS server.
+ Any attempt to operate a routed network without a WINS server while using NetBIOS
+ over TCP/IP protocols does not work unless on each client the name resolution
+ entries for the PDC are added to the <filename>LMHOSTS</filename>. This file is
+ normally located on the Windows XP Professional client in the
+ <filename>C:\WINDOWS\SYSTEM32\ETC\DRIVERS</filename> directory.
+ </para></listitem>
+
+ <listitem><para>
+ At this time the Samba WINS database cannot be replicated. That is
+ why a single WINS server is being implemented. This should work without a problem.
+ </para></listitem>
+
+ <listitem><para>
+ <indexterm><primary>winbindd</primary></indexterm>
+ BDCs make use of <command>winbindd</command> to provide
+ access to domain security credentials for file system access and object storage.
+ </para></listitem>
+
+ <listitem><para>
+ <indexterm><primary>DHCP</primary><secondary>relay</secondary></indexterm>
+ <indexterm><primary>DHCP</primary><secondary>requests</secondary></indexterm>
+ Configuration of Windows XP Professional clients is achieved using DHCP. Each
+ subnet has its own DHCP server. Backup DHCP serving is provided by one
+ alternate DHCP server. This necessitates enabling of the DHCP Relay agent on
+ all routers. The DHCP Relay agent must be programmed to pass DHCP Requests from the
+ network directed at the backup DHCP server.
+ </para></listitem>
+
+ <listitem><para>
+ All network users are granted the ability to print to any printer that is
+ network-attached. All printers are available from each server. Print jobs that
+ are spooled to a printer that is not on the local network segment are automatically
+ routed to the print spooler that is in control of that printer. The specific details
+ of how this might be done are demonstrated for one example only.
+ </para></listitem>
+
+ <listitem><para>
+ The network address and subnetmask chosen provide 1022 usable IP addresses in
+ each subnet. If in the future more addresses are required, it would make sense
+ to add further subnets rather than change addressing.
+ </para></listitem>
+
+ </itemizedlist>
+
+ </sect2>
+
+
+ <sect2>
+ <title>Political Issues</title>
+
+ <para>
+ This case gets close to the real world. You and I know the right way to implement
+ domain control. Politically, we have to navigate a minefield. In this case, the need is to
+ get the PDC rolled out in compliance with expectations and also to be ready to save the day
+ by having the real solution ready before it is needed. That real solution is presented in
+ <link linkend="happy"/>.
+ </para>
+
+ </sect2>
+
+</sect1>
+
+<sect1>
+ <title>Implementation</title>
+
+ <para>
+ The following configuration process begins following installation of Red Hat Fedora Core2 on the
+ three servers shown in the network topology diagram in <link linkend="chap05net"/>. You have
+ selected hardware that is appropriate to the task.
+ </para>
+
+ <figure id="chap05net">
+ <title>Network Topology &smbmdash; 500 User Network Using tdbsam passdb backend.</title>
+ <imagefile scale="50">chap5-net</imagefile>
+ </figure>
+
+ <sect2 id="ch5-dnshcp-setup">
+ <title>Installation of DHCP, DNS, and Samba Control Files</title>
+
+ <para>
+ Carefully install the configuration files into the correct locations as shown in
+ <link linkend="ch5-filelocations"/>. You should validate that the full file path is
+ correct as shown.
+ </para>
+
+ <para>
+ The abbreviation shown in this table as <constant>{VLN}</constant> refers to
+ the directory location beginning with <filename>/var/lib/named</filename>.
+ </para>
+
+
+ <table id="ch5-filelocations"><title>Domain: <constant>MEGANET</constant>, File Locations for Servers</title>
+ <tgroup cols="5">
+ <colspec colname='c1' align="left"/>
+ <colspec colname='c2' align="left"/>
+ <colspec colname='c3' align="center"/>
+ <colspec colname='c4' align="center"/>
+ <colspec colname='c5' align="center"/>
+ <thead>
+ <row>
+ <entry align="center" namest='c1' nameend='c2'>File Information</entry>
+ <entry align="center" namest="c3" nameend="c5">Server Name</entry>
+ </row>
+ <row>
+ <entry align="center">Source</entry>
+ <entry align="center">Target Location</entry>
+ <entry align="center">MASSIVE</entry>
+ <entry align="center">BLDG1</entry>
+ <entry align="center">BLDG2</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><link linkend="ch5-massivesmb"/></entry>
+ <entry><filename>/etc/samba/smb.conf</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="ch5-dc-common"/></entry>
+ <entry><filename>/etc/samba/dc-common.conf</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="ch5-commonsmb"/></entry>
+ <entry><filename>/etc/samba/common.conf</filename></entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="ch5-bldg1-smb"/></entry>
+ <entry><filename>/etc/samba/smb.conf</filename></entry>
+ <entry>No</entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="ch5-bldg2-smb"/></entry>
+ <entry><filename>/etc/samba/smb.conf</filename></entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="ch5-dommem-smb"/></entry>
+ <entry><filename>/etc/samba/dommem.conf</filename></entry>
+ <entry>No</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="massive-dhcp"/></entry>
+ <entry><filename>/etc/dhcpd.conf</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="bldg1dhcp"/></entry>
+ <entry><filename>/etc/dhcpd.conf</filename></entry>
+ <entry>No</entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="bldg2dhcp"/></entry>
+ <entry><filename>/etc/dhcpd.conf</filename></entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="massive-nameda"/></entry>
+ <entry><filename>/etc/named.conf (part A)</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="massive-namedb"/></entry>
+ <entry><filename>/etc/named.conf (part B)</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="massive-namedc"/></entry>
+ <entry><filename>/etc/named.conf (part C)</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="abmasbizdns"/></entry>
+ <entry><filename>{VLN}/master/abmas.biz.hosts</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="abmasusdns"/></entry>
+ <entry><filename>{VLN}/master/abmas.us.hosts</filename></entry>
+ <entry>Yes</entry>
+ <entry>No</entry>
+ <entry>No</entry>
+ </row>
+ <row>
+ <entry><link linkend="bldg12nameda"/></entry>
+ <entry><filename>/etc/named.conf (part A)</filename></entry>
+ <entry>No</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="bldg12namedb"/></entry>
+ <entry><filename>/etc/named.conf (part B)</filename></entry>
+ <entry>No</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="loopback"/></entry>
+ <entry><filename>{VLN}/localhost.zone</filename></entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="dnsloopy"/></entry>
+ <entry><filename>{VLN}/127.0.0.zone</filename></entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ <row>
+ <entry><link linkend="roothint"/></entry>
+ <entry><filename>{VLN}/root.hint</filename></entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ <entry>Yes</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ </sect2>
+
+ <sect2>
+ <title>Server Preparation: All Servers</title>
+
+ <para>
+ The following steps apply to all servers. Follow each step carefully.
+ </para>
+
+ <procedure>
+ <title>Server Preparation Steps</title>
+
+ <step><para>
+ Using the UNIX/Linux system tools, set the name of the server as shown in the network
+ topology diagram in <link linkend="chap05net"/>. For SUSE Linux products, the tool
+ that permits this is called <command>yast2</command>; for Red Hat Linux products,
+ you can use the <command>netcfg</command> tool.
+ Verify that your hostname is correctly set by running:
+<screen>
+&rootprompt; uname -n
+</screen>
+ An alternate method to verify the hostname is:
+<screen>
+&rootprompt; hostname -f
+</screen>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>/etc/hosts</primary></indexterm>
+ <indexterm><primary>named</primary></indexterm>
+ Edit your <filename>/etc/hosts</filename> file to include the primary names and addresses
+ of all network interfaces that are on the host server. This is necessary so that during
+ startup the system is able to resolve all its own names to the IP address prior to
+ startup of the DNS server. You should check the startup order of your system. If the
+ CUPS print server is started before the DNS server (<command>named</command>), you
+ should also include an entry for the printers in the <filename>/etc/hosts</filename> file.
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>/etc/resolv.conf</primary></indexterm>
+ All DNS name resolution should be handled locally. To ensure that the server is configured
+ correctly to handle this, edit <filename>/etc/resolv.conf</filename> so it has the following
+ content:
+<screen>
+search abmas.us abmas.biz
+nameserver 127.0.0.1
+</screen>
+ This instructs the name resolver function (when configured correctly) to ask the DNS server
+ that is running locally to resolve names to addresses.
+ </para></step>
+
+
+ <step><para>
+ <indexterm><primary>administrator</primary></indexterm>
+ <indexterm><primary>smbpasswd</primary></indexterm>
+ Add the <constant>root</constant> user to the password backend:
+<screen>
+&rootprompt; smbpasswd -a root
+New SMB password: XXXXXXXX
+Retype new SMB password: XXXXXXXX
+&rootprompt;
+</screen>
+ The <constant>root</constant> account is the UNIX equivalent of the Windows domain administrator.
+ This account is essential in the regular maintenance of your Samba server. It must never be
+ deleted. If for any reason the account is deleted, you may not be able to recreate this account
+ without considerable trouble.
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>username map</primary></indexterm>
+ <indexterm><primary>/etc/samba/smbusers</primary></indexterm>
+ Create the username map file to permit the <constant>root</constant> account to be called
+ <constant>Administrator</constant> from the Windows network environment. To do this, create
+ the file <filename>/etc/samba/smbusers</filename> with the following contents:
+<screen>
+####
+# User mapping file
+####
+# File Format
+# -----------
+# Unix_ID = Windows_ID
+#
+# Examples:
+# root = Administrator
+# janes = "Jane Smith"
+# jimbo = Jim Bones
+#
+# Note: If the name contains a space it must be double quoted.
+# In the example above the name 'jimbo' will be mapped to Windows
+# user names 'Jim' and 'Bones' because the space was not quoted.
+#######################################################################
+root = Administrator
+####
+# End of File
+####
+</screen>
+ </para></step>
+
+ <step><para>
+ Configure all network-attached printers to have a fixed IP address.
+ </para></step>
+
+ <step><para>
+ Create an entry in the DNS database on the server <constant>MASSIVE</constant>
+ in both the forward lookup database for the zone <constant>abmas.biz.hosts</constant>
+ and in the reverse lookup database for the network segment that the printer is
+ located in. Example configuration files for similar zones were presented in <link linkend="secure"/>,
+ <link linkend="abmasbiz"/> and <link linkend="eth2zone"/>.
+ </para></step>
+
+ <step><para>
+ Follow the instructions in the printer manufacturer's manuals to permit printing
+ to port 9100. Use any other port the manufacturer specifies for direct mode,
+ raw printing. This allows the CUPS spooler to print using raw mode protocols.
+ <indexterm><primary>CUPS</primary></indexterm>
+ <indexterm><primary>raw printing</primary></indexterm>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>CUPS</primary><secondary>queue</secondary></indexterm>
+ Only on the server to which the printer is attached configure the CUPS Print
+ Queues as follows:
+<screen>
+&rootprompt; lpadmin -p <parameter>printque</parameter> -v socket://<parameter>printer-name</parameter>.abmas.biz:9100 -E
+</screen>
+ <indexterm><primary>print filter</primary></indexterm>
+ This step creates the necessary print queue to use no assigned print filter. This
+ is ideal for raw printing, that is, printing without use of filters.
+ The name <parameter>printque</parameter> is the name you have assigned for
+ the particular printer.
+ </para></step>
+
+ <step><para>
+ Print queues may not be enabled at creation. Make certain that the queues
+ you have just created are enabled by executing the following:
+<screen>
+&rootprompt; /usr/bin/enable <parameter>printque</parameter>
+</screen>
+ </para></step>
+
+ <step><para>
+ Even though your print queue may be enabled, it is still possible that it
+ does not accept print jobs. A print queue services incoming printing
+ requests only when configured to do so. Ensure that your print queue is
+ set to accept incoming jobs by executing the following command:
+<screen>
+&rootprompt; /usr/bin/accept <parameter>printque</parameter>
+</screen>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>mime type</primary></indexterm>
+ <indexterm><primary>/etc/mime.convs</primary></indexterm>
+ <indexterm><primary>application/octet-stream</primary></indexterm>
+ This step, as well as the next one, may be omitted where CUPS version 1.1.18
+ or later is in use. Although it does no harm to follow it anyway, and may
+ help to avoid time spent later trying to figure out why print jobs may be
+ disappearing without a trace. Look at these two steps as <emphasis>insurance</emphasis>
+ against lost time. Edit file <filename>/etc/cups/mime.convs</filename> to
+ uncomment the line:
+<screen>
+application/octet-stream application/vnd.cups-raw 0 -
+</screen>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>/etc/mime.types</primary></indexterm>
+ Edit the file <filename>/etc/cups/mime.types</filename> to uncomment the line:
+<screen>
+application/octet-stream
+</screen>
+ </para></step>
+
+ <step><para>
+ Refer to the CUPS printing manual for instructions regarding how to configure
+ CUPS so that print queues that reside on CUPS servers on remote networks
+ route print jobs to the print server that owns that queue. The default setting
+ on your CUPS server may automatically discover remotely installed printers and
+ may permit this functionality without requiring specific configuration.
+ </para></step>
+
+ <step><para>
+ As part of the roll-out program, you need to configure the application's
+ server shares. This can be done once on the central server and may then be
+ replicated using a tool such as <command>rsync</command>. Refer to the man
+ page for <command>rsync</command> for details regarding use. The notes in
+ <link linkend="ch4appscfg"/> may help in your decisions to use an application
+ server facility.
+ </para></step>
+
+ </procedure>
+
+ <note><para>
+ Logon scripts that are run from a domain controller (PDC or BDC) are capable of using semi-intelligent
+ processes to automap Windows client drives to an application server that is nearest to the client. This
+ is considerably more difficult when a single PDC is used on a routed network. It can be done, but not
+ as elegantly as you see in the next chapter.
+ </para></note>
+
+ </sect2>
+
+ <sect2>
+ <title>Server-Specific Preparation</title>
+
+ <para>
+ There are some steps that apply to particular server functionality only. Each step is critical
+ to correct server operation. The following step-by-step installation guidance will assist you
+ in working through the process of configuring the PDC and then both BDC's.
+ </para>
+
+ <sect3>
+ <title>Configuration for Server: <constant>MASSIVE</constant></title>
+
+ <para>
+ The steps presented here attempt to implement Samba installation in a generic manner. While
+ some steps are clearly specific to Linux, it should not be too difficult to apply them to
+ your platform of choice.
+ </para>
+
+ <procedure>
+ <title>Primary Domain Controller Preparation</title>
+
+ <step><para>
+ <indexterm><primary>/etc/rc.d/boot.local</primary></indexterm>
+ <indexterm><primary>IP forwarding</primary></indexterm>
+ The host server acts as a router between the two internal network segments as well
+ as for all Internet access. This necessitates that IP forwarding be enabled. This can be
+ achieved by adding to the <filename>/etc/rc.d/boot.local</filename> an entry as follows:
+<screen>
+echo 1 > /proc/sys/net/ipv4/ip_forward
+</screen>
+ To ensure that your kernel is capable of IP forwarding during configuration, you may wish to execute
+ that command manually also. This setting permits the Linux system to act as a router.
+ </para></step>
+
+ <step><para>
+ This server is dual hosted (i.e., has two network interfaces) &smbmdash; one goes to the Internet
+ and the other to a local network that has a router that is the gateway to the remote networks.
+ You must therefore configure the server with route table entries so that it can find machines
+ on the remote networks. You can do this using the appropriate system tools for your Linux
+ server or using static entries that you place in one of the system startup files. It is best
+ to always use the tools that the operating system vendor provided. In the case of SUSE Linux, the
+ best tool to do this is YaST (refer to SUSE Administration Manual); in the case of Red Hat,
+ this is best done using the graphical system configuration tools (see the Red Hat documentation).
+ An example of how this may be done manually is as follows:
+<screen>
+&rootprompt; route add net 172.16.4.0 netmask 255.255.252.0 gw 172.16.0.128
+&rootprompt; route add net 172.16.8.0 netmask 255.255.252.0 gw 172.16.0.128
+</screen>
+ If you just execute these commands manually, the route table entries you have created are
+ not persistent across system reboots. You may add these commands directly to the local
+ startup files as follows: (SUSE) <filename>/etc/rc.d/boot.local</filename>, (Red Hat)
+ <filename>/etc/rc.d/init.d/rc.local</filename>.
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>/etc/nsswitch.conf</primary></indexterm>
+ The final step that must be completed is to edit the <filename>/etc/nsswitch.conf</filename> file.
+ This file controls the operation of the various resolver libraries that are part of the Linux
+ Glibc libraries. Edit this file so that it contains the following entries:
+<screen>
+hosts: files dns wins
+</screen>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>initGrps.sh</primary></indexterm>
+ Create and map Windows domain groups to UNIX groups. A sample script is provided in
+ <link linkend="ch5-initgrps"/>. Create a file containing this script. You called yours
+ <filename>/etc/samba/initGrps.sh</filename>. Set this file so it can be executed
+ and then execute the script. An example of the execution of this script as well as its
+ validation are shown in Section 4.3.2, Step 5.
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>/etc/passwd</primary></indexterm>
+ <indexterm><primary>password</primary><secondary>backend</secondary></indexterm>
+ <indexterm><primary>smbpasswd</primary></indexterm>
+ For each user who needs to be given a Windows domain account, make an entry in the
+ <filename>/etc/passwd</filename> file as well as in the Samba password backend.
+ Use the system tool of your choice to create the UNIX system account, and use the Samba
+ <command>smbpasswd</command> to create a domain user account.
+ </para>
+
+ <para>
+ <indexterm><primary>useradd</primary></indexterm>
+ <indexterm><primary>adduser</primary></indexterm>
+ <indexterm><primary>user</primary><secondary>management</secondary></indexterm>
+ There are a number of tools for user management under UNIX, such as
+ <command>useradd</command>, <command>adduser</command>, as well as a plethora of custom
+ tools. With the tool of your choice, create a home directory for each user.
+ </para></step>
+
+ <step><para>
+ Using the preferred tool for your UNIX system, add each user to the UNIX groups created
+ previously as necessary. File system access control is based on UNIX group membership.
+ </para></step>
+
+ <step><para>
+ Create the directory mount point for the disk subsystem that is to be mounted to provide
+ data storage for company files, in this case, the mount point indicated in the &smb.conf;
+ file is <filename>/data</filename>. Format the file system as required and mount the formatted
+ file system partition using appropriate system tools.
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>file system</primary>
+ <secondary>permissions</secondary></indexterm>
+ Create the top-level file storage directories for data and applications as follows:
+<screen>
+&rootprompt; mkdir -p /data/{accounts,finsvcs,pidata}
+&rootprompt; mkdir -p /apps
+&rootprompt; chown -R root:root /data
+&rootprompt; chown -R root:root /apps
+&rootprompt; chown -R bjordan:accounts /data/accounts
+&rootprompt; chown -R bjordan:finsvcs /data/finsvcs
+&rootprompt; chown -R bjordan:finsvcs /data/pidata
+&rootprompt; chmod -R ug+rwxs,o-rwx /data
+&rootprompt; chmod -R ug+rwx,o+rx-w /apps
+</screen>
+ Each department is responsible for creating its own directory structure within the departmental
+ share. The directory root of the <command>accounts</command> share is <filename>/data/accounts</filename>.
+ The directory root of the <command>finsvcs</command> share is <filename>/data/finsvcs</filename>.
+ The <filename>/apps</filename> directory is the root of the <constant>apps</constant> share
+ that provides the application server infrastructure.
+ </para></step>
+
+ <step><para>
+ The &smb.conf; file specifies an infrastructure to support roaming profiles and network
+ logon services. You can now create the file system infrastructure to provide the
+ locations on disk that these services require. Adequate planning is essential
+ because desktop profiles can grow to be quite large. For planning purposes, a minimum of
+ 200 MB of storage should be allowed per user for profile storage. The following
+ commands create the directory infrastructure needed:
+<screen>
+&rootprompt; mkdir -p /var/spool/samba
+&rootprompt; mkdir -p /var/lib/samba/{netlogon/scripts,profiles}
+&rootprompt; chown -R root:root /var/spool/samba
+&rootprompt; chown -R root:root /var/lib/samba
+&rootprompt; chmod a+rwxt /var/spool/samba
+</screen>
+ For each user account that is created on the system, the following commands should be
+ executed:
+<screen>
+&rootprompt; mkdir /var/lib/samba/profiles/'username'
+&rootprompt; chown 'username':users /var/lib/samba/profiles/'username'
+&rootprompt; chmod ug+wrx,o+rx,-w /var/lib/samba/profiles/'username'
+</screen>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>unix2dos</primary></indexterm>
+ <indexterm><primary>dos2unix</primary></indexterm>
+ Create a logon script. It is important that each line is correctly terminated with
+ a carriage return and line-feed combination (i.e., DOS encoding). The following procedure
+ works if the right tools (<constant>unxi2dos</constant> and <constant>dos2unix</constant>) are installed.
+ First, create a file called <filename>/var/lib/samba/netlogon/scripts/logon.bat.unix</filename>
+ with the following contents:
+<screen>
+net time \\massive /set /yes
+net use h: /home
+</screen>
+ Convert the UNIX file to a DOS file:
+<screen>
+&rootprompt; dos2unix &lt; /var/lib/samba/netlogon/scripts/logon.bat.unix \
+ &gt; /var/lib/samba/netlogon/scripts/logon.bat
+</screen>
+ </para></step>
+
+ <step><para>
+ There is one preparatory step without which you cannot have a working Samba network
+ environment. You must add an account for each network user. You can do this by executing
+ the following steps for each user:
+<screen>
+&rootprompt; useradd -m <parameter>username</parameter>
+&rootprompt; passwd <parameter>username</parameter>
+Changing password for <parameter>username</parameter>.
+New password: XXXXXXXX
+Re-enter new password: XXXXXXXX
+Password changed
+&rootprompt; smbpasswd -a <parameter>username</parameter>
+New SMB password: XXXXXXXX
+Retype new SMB password: XXXXXXXX
+Added user <parameter>username</parameter>.
+</screen>
+ You do, of course, use a valid user login ID in place of <parameter>username</parameter>.
+ </para></step>
+
+ <step><para>
+ Follow the processes shown in <link linkend="ch5-procstart"/> to start all services.
+ </para></step>
+
+ <step><para>
+ Your server is ready for validation testing. Do not proceed with the steps in
+ <link linkend="ch5-domsvrspec"/> until after the operation of the server has been
+ validated following the same methods as outlined in <link linkend="secure"/>, <link linkend="ch4valid"/>.
+ </para></step>
+
+ </procedure>
+
+ </sect3>
+
+ <sect3 id="ch5-domsvrspec">
+ <title>Configuration Specific to Domain Member Servers: <constant>BLDG1, BLDG2</constant></title>
+
+ <para>
+ The following steps will guide you through the nuances of implementing BDCs for the broadcast
+ isolated network segments. Remember that if the target installation platform is not Linux, it may
+ be necessary to adapt some commands to the equivalent on the target platform.
+ </para>
+
+ <procedure>
+ <title>Backup Domain Controller Configuration Steps</title>
+
+ <step><para>
+ <indexterm><primary>/etc/nsswitch.conf</primary></indexterm>
+ The final step that must be completed is to edit the <filename>/etc/nsswitch.conf</filename> file.
+ This file controls the operation of the various resolver libraries that are part of the Linux
+ Glibc libraries. Edit this file so that it contains the following entries:
+<screen>
+passwd: files winbind
+group: files winbind
+hosts: files dns wins
+</screen>
+ </para></step>
+
+ <step><para>
+ Follow the steps outlined in <link linkend="ch5-procstart"/> to start all services. Do not
+ start Samba at this time. Samba is controlled by the process called <command>smb</command>.
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>net</primary><secondary>rpc</secondary><tertiary>join</tertiary></indexterm>
+ You must now attempt to join the domain member servers to the domain. The following
+ instructions should be executed to effect this:
+<screen>
+&rootprompt; net rpc join
+</screen>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>service</primary><secondary>smb</secondary><tertiary>start</tertiary></indexterm>
+ You now start the Samba services by executing:
+<screen>
+&rootprompt; service smb start
+</screen>
+ </para></step>
+
+ <step><para>
+ Your server is ready for validation testing. Do not proceed with the steps in
+ <link linkend="ch5-domsvrspec"/> until after the operation of the server has been
+ validated following the same methods as outlined in <link linkend="ch4valid"/>.
+ </para></step>
+
+ </procedure>
+
+ </sect3>
+
+ </sect2>
+
+<!-- One -->
+<example id="ch5-massivesmb">
+<title>Server: MASSIVE (PDC), File: <filename>/etc/samba/smb.conf</filename></title>
+<smbconfblock>
+<smbconfcomment>Global parameters</smbconfcomment>
+<smbconfsection name="[global]"/>
+<smbconfoption name="workgroup">MEGANET</smbconfoption>
+<smbconfoption name="netbios name">MASSIVE</smbconfoption>
+<smbconfoption name="interfaces">eth1, lo</smbconfoption>
+<smbconfoption name="bind interfaces only">Yes</smbconfoption>
+<smbconfoption name="passdb backend">tdbsam</smbconfoption>
+<smbconfoption name="smb ports">139</smbconfoption>
+<smbconfoption name="add user script">/usr/sbin/useradd -m '%u'</smbconfoption>
+<smbconfoption name="delete user script">/usr/sbin/userdel -r '%u'</smbconfoption>
+<smbconfoption name="add group script">/usr/sbin/groupadd '%g'</smbconfoption>
+<smbconfoption name="delete group script">/usr/sbin/groupdel '%g'</smbconfoption>
+<smbconfoption name="add user to group script">/usr/sbin/usermod -G '%g' '%u'</smbconfoption>
+<smbconfoption name="add machine script">/usr/sbin/useradd -s /bin/false -d /var/lib/nobody '%u'</smbconfoption>
+<smbconfoption name="preferred master">Yes</smbconfoption>
+<smbconfoption name="wins support">Yes</smbconfoption>
+<smbconfoption name="include">/etc/samba/dc-common.conf</smbconfoption>
+
+<smbconfsection name="[accounts]"/>
+<smbconfoption name="comment">Accounting Files</smbconfoption>
+<smbconfoption name="path">/data/accounts</smbconfoption>
+<smbconfoption name="read only">No</smbconfoption>
+
+<smbconfsection name="[service]"/>
+<smbconfoption name="comment">Financial Services Files</smbconfoption>
+<smbconfoption name="path">/data/service</smbconfoption>
+<smbconfoption name="read only">No</smbconfoption>
+
+<smbconfsection name="[pidata]"/>
+<smbconfoption name="comment">Property Insurance Files</smbconfoption>
+<smbconfoption name="path">/data/pidata</smbconfoption>
+<smbconfoption name="read only">No</smbconfoption>
+</smbconfblock>
+</example>
+
+<!-- Two -->
+<example id="ch5-dc-common">
+<title>Server: MASSIVE (PDC), File: <filename>/etc/samba/dc-common.conf</filename></title>
+<smbconfblock>
+<smbconfcomment>Global parameters</smbconfcomment>
+<smbconfsection name="[global]"/>
+<smbconfoption name="shutdown script">/var/lib/samba/scripts/shutdown.sh</smbconfoption>
+<smbconfoption name="abort shutdown script">/sbin/shutdown -c</smbconfoption>
+<smbconfoption name="logon script">scripts\logon.bat</smbconfoption>
+<smbconfoption name="logon path">\%L\profiles\%U</smbconfoption>
+<smbconfoption name="logon drive">X:</smbconfoption>
+<smbconfoption name="logon home">\%L\%U</smbconfoption>
+<smbconfoption name="domain logons">Yes</smbconfoption>
+<smbconfoption name="preferred master">Yes</smbconfoption>
+<smbconfoption name="include">/etc/samba/common.conf</smbconfoption>
+
+<smbconfsection name="[homes]"/>
+<smbconfoption name="comment">Home Directories</smbconfoption>
+<smbconfoption name="valid users">%S</smbconfoption>
+<smbconfoption name="read only">No</smbconfoption>
+<smbconfoption name="browseable">No</smbconfoption>
+
+<smbconfsection name="[netlogon]"/>
+<smbconfoption name="comment">Network Logon Service</smbconfoption>
+<smbconfoption name="path">/var/lib/samba/netlogon</smbconfoption>
+<smbconfoption name="guest ok">Yes</smbconfoption>
+<smbconfoption name="locking">No</smbconfoption>
+
+<smbconfsection name="[profiles]"/>
+<smbconfoption name="comment">Profile Share</smbconfoption>
+<smbconfoption name="path">/var/lib/samba/profiles</smbconfoption>
+<smbconfoption name="read only">No</smbconfoption>
+<smbconfoption name="profile acls">Yes</smbconfoption>
+</smbconfblock>
+</example>
+
+<!-- Three -->
+<example id="ch5-commonsmb">
+<title>Common Samba Configuration File: <filename>/etc/samba/common.conf</filename></title>
+<smbconfblock>
+<smbconfsection name="[global]"/>
+<smbconfoption name="username map">/etc/samba/smbusers</smbconfoption>
+<smbconfoption name="log level">1</smbconfoption>
+<smbconfoption name="syslog">0</smbconfoption>
+<smbconfoption name="log file">/var/log/samba/%m</smbconfoption>
+<smbconfoption name="max log size">50</smbconfoption>
+<smbconfoption name="smb ports">139</smbconfoption>
+<smbconfoption name="name resolve order">wins bcast hosts</smbconfoption>
+<smbconfoption name="time server">Yes</smbconfoption>
+<smbconfoption name="printcap name">CUPS</smbconfoption>
+<smbconfoption name="show add printer wizard">No</smbconfoption>
+<smbconfoption name="shutdown script">/var/lib/samba/scripts/shutdown.sh</smbconfoption>
+<smbconfoption name="abort shutdown script">/sbin/shutdown -c</smbconfoption>
+<smbconfoption name="utmp">Yes</smbconfoption>
+<smbconfoption name="map acl inherit">Yes</smbconfoption>
+<smbconfoption name="printing">cups</smbconfoption>
+<smbconfoption name="veto files">/*.eml/*.nws/*.{*}/</smbconfoption>
+<smbconfoption name="veto oplock files">/*.doc/*.xls/*.mdb/</smbconfoption>
+<smbconfoption name="include"> </smbconfoption>
+
+<smbconfcomment>Share and Service Definitions are common to all servers</smbconfcomment>
+<smbconfsection name="[printers]"/>
+<smbconfoption name="comment">SMB Print Spool</smbconfoption>
+<smbconfoption name="path">/var/spool/samba</smbconfoption>
+<smbconfoption name="guest ok">Yes</smbconfoption>
+<smbconfoption name="printable">Yes</smbconfoption>
+<smbconfoption name="use client driver">Yes</smbconfoption>
+<smbconfoption name="default devmode">Yes</smbconfoption>
+<smbconfoption name="browseable">No</smbconfoption>
+
+<smbconfsection name="[apps]"/>
+<smbconfoption name="comment">Application Files</smbconfoption>
+<smbconfoption name="path">/apps</smbconfoption>
+<smbconfoption name="admin users">bjordan</smbconfoption>
+<smbconfoption name="read only">No</smbconfoption>
+</smbconfblock>
+</example>
+
+<!-- Four -->
+<example id="ch5-bldg1-smb">
+<title>Server: BLDG1 (Member), File: smb.conf</title>
+<smbconfblock>
+<smbconfcomment>Global parameters</smbconfcomment>
+<smbconfsection name="[global]"/>
+<smbconfoption name="workgroup">MEGANET</smbconfoption>
+<smbconfoption name="netbios name">BLDG1</smbconfoption>
+<smbconfoption name="include">/etc/samba/dom-mem.conf</smbconfoption>
+</smbconfblock>
+</example>
+
+<!-- Five -->
+<example id="ch5-bldg2-smb">
+<title>Server: BLDG2 (Member), File: smb.conf</title>
+<smbconfblock>
+<smbconfcomment>Global parameters</smbconfcomment>
+<smbconfsection name="[global]"/>
+<smbconfoption name="workgroup">MEGANET</smbconfoption>
+<smbconfoption name="netbios name">BLDG2</smbconfoption>
+<smbconfoption name="include">/etc/samba/dom-mem.conf</smbconfoption>
+</smbconfblock>
+</example>
+
+<!-- Six -->
+<example id="ch5-dommem-smb">
+<title>Common Domain Member Include File: dom-mem.conf</title>
+<smbconfblock>
+<smbconfcomment>Global parameters</smbconfcomment>
+<smbconfsection name="[global]"/>
+<smbconfoption name="shutdown script">/var/lib/samba/scripts/shutdown.sh</smbconfoption>
+<smbconfoption name="abort shutdown script">/sbin/shutdown -c</smbconfoption>
+<smbconfoption name="preferred master">Yes</smbconfoption>
+<smbconfoption name="wins server">172.16.0.1</smbconfoption>
+<smbconfoption name="idmap uid">15000-20000</smbconfoption>
+<smbconfoption name="idmap gid">15000-20000</smbconfoption>
+<smbconfoption name="include">/etc/samba/common.conf</smbconfoption>
+</smbconfblock>
+</example>
+
+<!-- Seven -->
+<example id="massive-dhcp">
+<title>Server: MASSIVE, File: dhcpd.conf</title>
+<screen>
+# Abmas Accounting Inc.
+
+default-lease-time 86400;
+max-lease-time 172800;
+default-lease-time 86400;
+ddns-updates on;
+ddns-update-style interim;
+
+option ntp-servers 172.16.0.1;
+option domain-name "abmas.biz";
+option domain-name-servers 172.16.0.1, 172.16.4.1;
+option netbios-name-servers 172.16.0.1;
+option netbios-node-type 8;
+
+subnet 172.16.1.0 netmask 255.255.252.0 {
+ range dynamic-bootp 172.16.1.0 172.16.2.255;
+ option subnet-mask 255.255.252.0;
+ option routers 172.16.0.1, 172.16.0.128;
+ allow unknown-clients;
+ }
+subnet 172.16.4.0 netmask 255.255.252.0 {
+ range dynamic-bootp 172.16.7.0 172.16.7.254;
+ option subnet-mask 255.255.252.0;
+ option routers 172.16.4.128;
+ allow unknown-clients;
+ }
+subnet 172.16.8.0 netmask 255.255.252.0 {
+ range dynamic-bootp 172.16.11.0 172.16.11.254;
+ option subnet-mask 255.255.252.0;
+ option routers 172.16.4.128;
+ allow unknown-clients;
+ }
+subnet 127.0.0.0 netmask 255.0.0.0 {
+ }
+subnet 123.45.67.64 netmask 255.255.255.252 {
+ }
+</screen>
+</example>
+
+<!-- Eight -->
+<example id="bldg1dhcp">
+<title>Server: BLDG1, File: dhcpd.conf</title>
+<screen>
+# Abmas Accounting Inc.
+
+default-lease-time 86400;
+max-lease-time 172800;
+default-lease-time 86400;
+ddns-updates on;
+ddns-update-style ad-hoc;
+
+option ntp-servers 172.16.0.1;
+option domain-name "abmas.biz";
+option domain-name-servers 172.16.0.1, 172.16.4.1;
+option netbios-name-servers 172.16.0.1;
+option netbios-node-type 8;
+
+subnet 172.16.1.0 netmask 255.255.252.0 {
+ range dynamic-bootp 172.16.3.0 172.16.3.255;
+ option subnet-mask 255.255.252.0;
+ option routers 172.16.0.1, 172.16.0.128;
+ allow unknown-clients;
+ }
+subnet 172.16.4.0 netmask 255.255.252.0 {
+ range dynamic-bootp 172.16.5.0 172.16.6.255;
+ option subnet-mask 255.255.252.0;
+ option routers 172.16.4.128;
+ allow unknown-clients;
+ }
+subnet 127.0.0.0 netmask 255.0.0.0 {
+ }
+</screen>
+</example>
+
+<!-- Nine -->
+<example id="bldg2dhcp">
+<title>Server: BLDG2, File: dhcpd.conf</title>
+<screen>
+# Abmas Accounting Inc.
+
+default-lease-time 86400;
+max-lease-time 172800;
+default-lease-time 86400;
+ddns-updates on;
+ddns-update-style interim;
+
+option ntp-servers 172.16.0.1;
+option domain-name "abmas.biz";
+option domain-name-servers 172.16.0.1, 172.16.4.1;
+option netbios-name-servers 172.16.0.1;
+option netbios-node-type 8;
+
+subnet 172.16.8.0 netmask 255.255.252.0 {
+ range dynamic-bootp 172.16.9.0 172.16.10.255;
+ option subnet-mask 255.255.252.0;
+ option routers 172.16.8.128;
+ allow unknown-clients;
+ }
+subnet 127.0.0.0 netmask 255.0.0.0 {
+ }
+</screen>
+</example>
+
+<!-- Ten -->
+<example id="massive-nameda">
+<title>Server: MASSIVE, File: named.conf, Part: A</title>
+<screen>
+###
+# Abmas Biz DNS Control File
+###
+# Date: November 15, 2003
+###
+options {
+ directory "/var/lib/named";
+ forwarders {
+ 123.45.12.23;
+ 123.45.54.32;
+ };
+ forward first;
+ listen-on {
+ mynet;
+ };
+ auth-nxdomain yes;
+ multiple-cnames yes;
+ notify no;
+};
+
+zone "." in {
+ type hint;
+ file "root.hint";
+};
+
+zone "localhost" in {
+ type master;
+ file "localhost.zone";
+};
+
+zone "0.0.127.in-addr.arpa" in {
+ type master;
+ file "127.0.0.zone";
+};
+
+acl mynet {
+ 172.16.0.0/24;
+ 172.16.4.0/24;
+ 172.16.8.0/24;
+ 127.0.0.1;
+};
+
+acl seconddns {
+ 123.45.54.32;
+};
+</screen>
+</example>
+
+<!-- Eleven -->
+<example id="massive-namedb">
+<title>Server: MASSIVE, File: named.conf, Part: B</title>
+<screen>
+zone "abmas.biz" {
+ type master;
+ file "/var/lib/named/master/abmas.biz.hosts";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+ allow-update {
+ mynet;
+ };
+};
+
+zone "abmas.us" {
+ type master;
+ file "/var/lib/named/master/abmas.us.hosts";
+ allow-query {
+ all;
+ };
+ allow-transfer {
+ seconddns;
+ };
+};
+</screen>
+</example>
+
+<!-- Twelve -->
+<example id="massive-namedc">
+<title>Server: MASSIVE, File: named.conf, Part: C</title>
+<screen>
+zone "0.16.172.in-addr.arpa" {
+ type master;
+ file "/var/lib/named/master/172.16.0.0.rev";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+ allow-update {
+ mynet;
+ };
+};
+
+zone "4.16.172.in-addr.arpa" {
+ type master;
+ file "/var/lib/named/master/172.16.4.0.rev";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+ allow-update {
+ mynet;
+ };
+};
+
+zone "8.16.172.in-addr.arpa" {
+ type master;
+ file "/var/lib/named/master/172.16.8.0.rev";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+ allow-update {
+ mynet;
+ };
+};
+</screen>
+</example>
+
+<!-- Thirteen -->
+<example id="abmasbizdns">
+<title>Forward Zone File: abmas.biz.hosts</title>
+<screen>
+$ORIGIN .
+$TTL 38400 ; 10 hours 40 minutes
+abmas.biz IN SOA massive.abmas.biz. root.abmas.biz. (
+ 2003021833 ; serial
+ 10800 ; refresh (3 hours)
+ 3600 ; retry (1 hour)
+ 604800 ; expire (1 week)
+ 38400 ; minimum (10 hours 40 minutes)
+ )
+ NS massive.abmas.biz.
+ NS bldg1.abmas.biz.
+ NS bldg2.abmas.biz.
+ MX 10 massive.abmas.biz.
+$ORIGIN abmas.biz.
+massive A 172.16.0.1
+router0 A 172.16.0.128
+bldg1 A 172.16.4.1
+router4 A 172.16.4.128
+bldg2 A 172.16.8.1
+router8 A 172.16.8.128
+</screen>
+</example>
+
+<!-- Forteen -->
+<example id="abmasusdns">
+<title>Forward Zone File: abmas.biz.hosts</title>
+<screen>
+$ORIGIN .
+$TTL 38400 ; 10 hours 40 minutes
+abmas.us IN SOA server.abmas.us. root.abmas.us. (
+ 2003021833 ; serial
+ 10800 ; refresh (3 hours)
+ 3600 ; retry (1 hour)
+ 604800 ; expire (1 week)
+ 38400 ; minimum (10 hours 40 minutes)
+ )
+ NS dns.abmas.us.
+ NS dns2.abmas.us.
+ MX 10 mail.abmas.us.
+$ORIGIN abmas.us.
+server A 123.45.67.66
+dns2 A 123.45.54.32
+gw A 123.45.67.65
+www CNAME server
+mail CNAME server
+dns CNAME server
+</screen>
+</example>
+
+<!-- Fifteen -->
+<example id="bldg12nameda">
+<title>Servers: BLDG1/BLDG2, File: named.conf, Part: A</title>
+<screen>
+###
+# Abmas Biz DNS Control File
+###
+# Date: November 15, 2003
+###
+options {
+ directory "/var/lib/named";
+ forwarders {
+ 172.16.0.1;
+ };
+ forward first;
+ listen-on {
+ mynet;
+ };
+ auth-nxdomain yes;
+ multiple-cnames yes;
+ notify no;
+};
+
+zone "." in {
+ type hint;
+ file "root.hint";
+};
+
+zone "localhost" in {
+ type master;
+ file "localhost.zone";
+};
+
+zone "0.0.127.in-addr.arpa" in {
+ type master;
+ file "127.0.0.zone";
+};
+
+acl mynet {
+ 172.16.0.0/24;
+ 172.16.4.0/24;
+ 172.16.8.0/24;
+ 127.0.0.1;
+};
+
+acl seconddns {
+ 123.45.54.32;
+};
+</screen>
+</example>
+
+<!-- Sixteen -->
+<example id="bldg12namedb">
+<title>Servers: BLDG1/BLDG2, File: named.conf, Part: B</title>
+<screen>
+zone "abmas.biz" {
+ type slave;
+ file "/var/lib/named/slave/abmas.biz.hosts";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+};
+
+zone "0.16.172.in-addr.arpa" {
+ type slave;
+ file "/var/lib/slave/master/172.16.0.0.rev";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+};
+
+zone "4.16.172.in-addr.arpa" {
+ type slave;
+ file "/var/lib/named/slave/172.16.4.0.rev";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+};
+
+zone "8.16.172.in-addr.arpa" {
+ type slave;
+ file "/var/lib/named/slave/172.16.8.0.rev";
+ allow-query {
+ mynet;
+ };
+ allow-transfer {
+ mynet;
+ };
+};
+</screen>
+</example>
+
+
+<!-- Seventeen -->
+<example id="ch5-initgrps">
+<title>Initialize Groups Script, File: /etc/samba/initGrps.sh</title>
+<screen>
+#!/bin/bash
+
+# Create UNIX groups
+groupadd acctsdep
+groupadd finsrvcs
+groupadd piops
+
+# Map Windows Domain Groups to UNIX groups
+net groupmap add ntgroup="Domain Admins" unixgroup=root type=d
+net groupmap add ntgroup="Domain Users" unixgroup=users type=d
+net groupmap add ntgroup="Domain Guests" unixgroup=nobody type=d
+
+# Add Functional Domain Groups
+net groupmap add ntgroup="Accounts Dept" unixgroup=acctsdep type=d
+net groupmap add ntgroup="Financial Services" unixgroup=finsrvcs type=d
+net groupmap add ntgroup="Insurance Group" unixgroup=piops type=d
+</screen>
+</example>
+
+<!-- End of Examples -->
+
+ <sect2 id="ch5-procstart">
+ <title>Process Startup Configuration</title>
+
+ <para>
+ <indexterm><primary>chkconfig</primary></indexterm>
+ <indexterm><primary>daemon control</primary></indexterm>
+ There are two essential steps to process startup configuration. A process
+ must be configured so that it is automatically restarted each time the server
+ is rebooted. This step involves use of the <command>chkconfig</command> tool that
+ created appropriate symbolic links from the master daemon control file that is
+ located in the <filename>/etc/rc.d</filename> directory to the <filename>/etc/rc'x'.d</filename>
+ directories. Links are created so that when the system run-level is changed, the
+ necessary start or kill script is run.
+ </para>
+
+ <para>
+ <indexterm><primary>/etc/xinetd.d</primary></indexterm>
+ In the event that a service is provided not as a daemon but via the internetworking
+ super daemon (<command>inetd</command> or <command>xinetd</command>), then the <command>chkconfig</command>
+ tool makes the necessary entries in the <filename>/etc/xinetd.d</filename> directory
+ and sends a hang-up (HUP) signal to the super daemon, thus forcing it to
+ re-read its control files.
+ </para>
+
+ <para>
+ Last, each service must be started to permit system validation to proceed. The following steps
+ are for a Red Hat Linux system, please adapt them to suit the target OS platform on which you
+ are installing Samba.
+ </para>
+
+ <procedure>
+ <title>Process Startup Configuration Steps</title>
+
+ <step><para>
+ Use the standard system tool to configure each service to restart
+ automatically at every system reboot. For example,
+ <indexterm><primary>chkconfig</primary></indexterm>
+<screen>
+&rootprompt; chkconfig dhpc on
+&rootprompt; chkconfig named on
+&rootprompt; chkconfig cups on
+&rootprompt; chkconfig smb on
+&rootprompt; chkconfig swat on
+</screen>
+ </para></step>
+
+ <step><para>
+ <indexterm><primary>starting dhcpd</primary></indexterm>
+ <indexterm><primary>starting samba</primary></indexterm>
+ <indexterm><primary>starting CUPS</primary></indexterm>
+ Now start each service to permit the system to be validated.
+ Execute each of the following in the sequence shown:
+
+<screen>
+&rootprompt; service dhcp restart
+&rootprompt; service named restart
+&rootprompt; service cups restart
+&rootprompt; service smb restart
+&rootprompt; service swat restart
+</screen>
+ </para></step>
+ </procedure>
+
+ </sect2>
+
+ <sect2 id="ch5wincfg">
+ <title>Windows Client Configuration</title>
+
+ <para>
+ The procedure for desktop client configuration for the network in this chapter is similar to
+ that used for the previous one. There are a few subtle changes that should be noted.
+ </para>
+
+ <procedure>
+ <title>Windows Client Configuration Steps</title>
+
+ <step><para>
+ Install MS Windows XP Professional. During installation, configure the client to use DHCP for
+ TCP/IP protocol configuration.
+ <indexterm><primary>WINS</primary></indexterm>
+ <indexterm><primary>DHCP</primary></indexterm>
+ DHCP configures all Windows clients to use the WINS Server address that has been defined
+ for the local subnet.
+ </para></step>
+
+ <step><para>
+ Join the Windows domain <constant>MEGANET</constant>. Use the domain administrator
+ username <constant>root</constant> and the SMB password you assigned to this account.
+ A detailed step-by-step procedure for joining a Windows 200x/XP Professional client to
+ a Windows domain is given in <link linkend="appendix"/>, <link linkend="domjoin"/>.
+ Reboot the machine as prompted and then log on using the domain administrator account
+ (<constant>root</constant>).
+ </para></step>
+
+ <step><para>
+ Verify that the server called <constant>MEGANET</constant> is visible in <guimenu>My Network Places</guimenu>,
+ that it is possible to connect to it and see the shares <guimenuitem>accounts</guimenuitem>,
+ <guimenuitem>apps</guimenuitem>, and <guimenuitem>finsvcs</guimenuitem>,
+ and that it is possible to open each share to reveal its contents.
+ </para></step>
+
+ <step><para>
+ Create a drive mapping to the <constant>apps</constant> share on a server. At this time, it does
+ not particularly matter which application server is used. It is necessary to manually
+ set a persistent drive mapping to the local applications server on each workstation at the time of
+ installation. This step is avoided by the improvements to the design of the network configuration
+ in the next chapter.
+ </para></step>
+
+ <step><para>
+ Perform an administrative installation of each application to be used. Select the options
+ that you wish to use. Of course, you choose to run applications over the network, correct?
+ </para></step>
+
+ <step><para>
+ Now install all applications to be installed locally. Typical tools include Adobe Acrobat,
+ NTP-based time synchronization software, drivers for specific local devices such as fingerprint
+ scanners, and the like. Probably the most significant application to be locally installed
+ is antivirus software.
+ </para></step>
+
+ <step><para>
+ Now install all four printers onto the staging system. The printers you install
+ include the accounting department HP LaserJet 6 and Minolta QMS Magicolor printers, and you
+ also configure use of the identical printers that are located in the financial services department.
+ Install printers on each machine using the following steps:
+
+ <procedure>
+ <title>Steps to Install Printer Drivers on Windows Clients</title>
+
+ <step><para>
+ Click <menuchoice>
+ <guimenu>Start</guimenu>
+ <guimenuitem>Settings</guimenuitem>
+ <guimenuitem>Printers</guimenuitem>
+ <guiicon>Add Printer</guiicon>
+ <guibutton>Next</guibutton>
+ </menuchoice>. Do not click <guimenuitem>Network printer</guimenuitem>.
+ Ensure that <guimenuitem>Local printer</guimenuitem> is selected.
+ </para></step>
+
+ <step><para>
+ Click <guibutton>Next</guibutton>. In the
+ <guimenuitem>Manufacturer:</guimenuitem> panel, select <constant>HP</constant>.
+ In the <guimenuitem>Printers:</guimenuitem> panel, select the printer called
+ <constant>HP LaserJet 6</constant>. Click <guibutton>Next</guibutton>.
+ </para></step>
+
+ <step><para>
+ In the <guimenuitem>Available ports:</guimenuitem> panel, select
+ <constant>FILE:</constant>. Accept the default printer name by clicking
+ <guibutton>Next</guibutton>. When asked, <quote>Would you like to print a
+ test page?</quote>, click <guimenuitem>No</guimenuitem>. Click
+ <guibutton>Finish</guibutton>.
+ </para></step>
+
+ <step><para>
+ You may be prompted for the name of a file to print to. If so, close the
+ dialog panel. Right-click <menuchoice>
+ <guiicon>HP LaserJet 6</guiicon>
+ <guimenuitem>Properties</guimenuitem>
+ <guimenusub>Details (Tab)</guimenusub>
+ <guimenubutton>Add Port</guimenubutton>
+ </menuchoice>.
+ </para></step>
+
+ <step><para>
+ In the <guimenuitem>Network</guimenuitem> panel, enter the name of
+ the print queue on the Samba server as follows: <constant>\\BLDG1\hplj6a</constant>.
+ Click <menuchoice>
+ <guibutton>OK</guibutton>
+ <guibutton>OK</guibutton>
+ </menuchoice> to complete the installation.
+ </para></step>
+
+ <step><para>
+ Repeat the printer installation steps above for both HP LaserJet 6 printers
+ as well as for both QMS Magicolor laser printers. Remember to install all
+ printers but to set the destination port for each to the server on the
+ local network. For example, a workstation in the accounting group should
+ have all printers directed at the server <constant>BLDG1</constant>.
+ You may elect to point all desktop workstation configurations at the
+ server called <constant>MASSIVE</constant> and then in your deployment
+ procedures, it would be wise to document the need to redirect the printer
+ configuration (as well as the applications server drive mapping) to the
+ server on the network segment on which the workstation is to be located.
+ </para></step>
+ </procedure>
+ </para></step>
+
+ <step><para>
+ When you are satisfied that the staging systems are complete, use the appropriate procedure to
+ remove the client from the domain. Reboot the system, and then log on as the local administrator
+ and clean out all temporary files stored on the system. Before shutting down, use the disk
+ defragmentation tool so that the file system is in optimal condition before replication.
+ </para></step>
+
+ <step><para>
+ Boot the workstation using the Norton (Symantec) Ghosting disk (or CD-ROM) and image the
+ machine to a network share on the server.
+ </para></step>
+
+ <step><para>
+ You may now replicate the image using the appropriate Norton Ghost procedure to the target
+ machines. Make sure to use the procedure that ensures each machine has a unique
+ Windows security identifier (SID). When the installation of the disk image is complete, boot the PC.
+ </para></step>
+
+ <step><para>
+ Log onto the machine as the local Administrator (the only option), and join the machine to
+ the domain following the procedure set out in <link linkend="appendix"/>, <link linkend="domjoin"/>. You must now set the
+ persistent drive mapping to the applications server that the user is to use. The system is now
+ ready for the user to log on, provided you have created a network logon account for that
+ user, of course.
+ </para></step>
+
+ <step><para>
+ Instruct all users to log onto the workstation using their assigned username and password.
+ </para></step>
+ </procedure>
+
+ </sect2>
+
+ <sect2>
+ <title>Key Points Learned</title>
+
+ <para>
+ The network you have just deployed has been a valuable exercise in forced constraint.
+ You have deployed a network that works well, although you may soon start to see
+ performance problems, at which time the modifications demonstrated in <link linkend="happy"/>
+ bring the network to life. The following key learning points were experienced:
+ </para>
+
+ <itemizedlist>
+ <listitem><para>
+ The power of using &smb.conf; include files
+ </para></listitem>
+
+ <listitem><para>
+ Use of a single PDC over a routed network
+ </para></listitem>
+
+ <listitem><para>
+ Joining a Samba-3 domain member server to a Samba-3 domain
+ </para></listitem>
+
+ <listitem><para>
+ Configuration of winbind to use domain users and groups for Samba access
+ to resources on the domain member servers
+ </para></listitem>
+
+ <listitem><para>
+ The introduction of roaming profiles
+ </para></listitem>
+
+ </itemizedlist>
+
+ </sect2>
+
+</sect1>
+
+<sect1>
+ <title>Questions and Answers</title>
+
+ <para>
+ </para>
+
+ <qandaset defaultlabel="chap01qa" type="number">
+ <qandaentry>
+ <question>
+
+ <para>
+ The example &smb.conf; files in this chapter make use of the <parameter>include</parameter> facility.
+ How may I get to see what the actual working &smb.conf; settings are?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ You may readily see the net compound effect of the included files by running:
+<screen>
+&rootprompt; testparm -s | less
+</screen>
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ Why does the include file <filename>common.conf</filename> have an empty include statement?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ The use of the empty include statement nullifies further includes. For example, let's say you
+ desire to have just an smb.conf file that is built from the array of include files of which the
+ master control file is called <filename>master.conf</filename>. The following command
+ produces a compound &smb.conf; file.
+<screen>
+&rootprompt; testparm -s /etc/samba/master.conf > /etc/samba/smb.conf
+</screen>
+ If the include parameter was not in the common.conf file, the final &smb.conf; file leaves
+ the include in place, even though the file it points to has already been included. This is a bug
+ that will be fixed at a future date.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ I accept that the simplest configuration necessary to do the job is the best. The use of <parameter>tdbsam</parameter>
+ passdb backend is much simpler than having to manage an LDAP-based <parameter>ldapsam</parameter> passdb backend.
+ I tried using <command>rsync</command> to replicate the <filename>passdb.tdb</filename>, and it seems to work fine!
+ So what is the problem?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ Replication of the <parameter>tdbsam</parameter> database file can result in loss of currency in its
+ contents between the PDC and BDCs. The most notable symptom is that workstations may not be able
+ to log onto the network following a reboot and may have to rejoin the domain to recover network
+ access capability.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ You are using DHCP Relay enabled on the routers as well as a local DHCP server. Will this cause a clash?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ No. It is possible to have as many DHCP servers on a network segment as makes sense. A DHCP server
+ offers an IP address lease, but it is the client that determines which offer is accepted, no matter how many
+ offers are made. Under normal operation, the client accepts the first offer it receives.
+ </para>
+
+ <para>
+ The only exception to this rule is when the client makes a directed request from a specific DHCP server
+ for renewal of the lease it has. This means that under normal circumstances there is no risk of a clash.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ How does the Windows client find the PDC?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ The Windows client obtains the WINS server address from the DHCP lease information. It also
+ obtains from the DHCP lease information the parameter that causes it to use directed UDP (UDP Unicast)
+ to register itself with the WINS server and to obtain enumeration of vital network information to
+ enable it to operate successfully.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ Why did you enable IP forwarding (routing) only on the server called <constant>MASSIVE</constant>?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ The server called <constant>MASSIVE</constant> is acting as a router to the Internet. No other server
+ (BLDG1 or BLDG2) has any need for IP forwarding because they are attached only to their own network.
+ Route table entries are needed to direct MASSIVE to send all traffic intended for the remote network
+ segments to the router that is its gateway to them.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ You did nothing special to implement roaming profiles. Why?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ Unless configured to do otherwise, the default behavior with Samba-3 and Windows XP Professional
+ clients is to use roaming profiles.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ On the domain member computers, you configured winbind in the <filename>/etc/nsswitch.conf</filename> file.
+ You did not configure any PAM settings. Is this an omission?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ PAM is needed only for authentication. When Samba is using Microsoft encrypted passwords, it makes only
+ marginal use of PAM. PAM configuration handles only authentication. If you want to log onto the domain
+ member servers using Windows networking usernames and passwords, it is necessary to configure PAM
+ to enable the use of winbind. Samba makes use only of the identity resolution facilities of the name
+ service switch (NSS).
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ You are starting SWAT up on this example but have not discussed that anywhere. Why did you do this?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ Oh, I did not think you would notice that. It is there so that it can be used. This is more fully discussed
+ in <emphasis>TOSHARG2</emphasis>, which has a full chapter dedicated to the subject. While we are on the
+ subject, it should be noted that you should definitely not use SWAT on any system that makes use
+ of &smb.conf; <parameter>include</parameter> files because SWAT optimizes them out into an aggregated
+ file but leaves in place a broken reference to the top-layer include file. SWAT was not designed to
+ handle this functionality gracefully.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ <qandaentry>
+ <question>
+
+ <para>
+ The domain controller has an auto-shutdown script. Isn't that dangerous?
+ </para>
+
+ </question>
+ <answer>
+
+ <para>
+ Well done, you spotted that! I guess it is dangerous. It is good to know that you can do this, though.
+ </para>
+
+ </answer>
+ </qandaentry>
+
+ </qandaset>
+
+</sect1>
+
+</chapter>
+