release/src/router/samba3/docs/htmldocs/Samba3-HOWTO/DNSDHCP.html

   1 <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>Chapter 47. DNS and DHCP Configuration Guide</title><link rel="stylesheet" href="samba.css" type="text/css"><meta name="generator" content="DocBook XSL Stylesheets V1.70.1"><link rel="start" href="index.html" title="The Official Samba-3 HOWTO and Reference Guide"><link rel="up" href="Appendix.html" title="Part VI. Reference Section"><link rel="prev" href="ch46.html" title="Chapter 46. Samba Support"><link rel="next" href="gpl.html" title="Appendix A. GNU General Public License"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center">Chapter 47. DNS and DHCP Configuration Guide</th></tr><tr><td width="20%" align="left"><a accesskey="p" href="ch46.html">Prev</a> </td><th width="60%" align="center">Part VI. Reference Section</th><td width="20%" align="right"> <a accesskey="n" href="gpl.html">Next</a></td></tr></table><hr></div><div class="chapter" lang="en"><div class="titlepage"><div><div><h2 class="title"><a name="DNSDHCP"></a>Chapter 47. DNS and DHCP Configuration Guide</h2></div><div><div class="author"><h3 class="author"><span class="firstname">John</span> <span class="othername">H.</span> <span class="surname">Terpstra</span></h3><div class="affiliation"><span class="orgname">Samba Team<br></span><div class="address"><p><code class="email">&lt;<a href="mailto:jht@samba.org">jht@samba.org</a>&gt;</code></p></div></div></div></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl><dt><span class="sect1"><a href="DNSDHCP.html#id2694832">Features and Benefits</a></span></dt><dt><span class="sect1"><a href="DNSDHCP.html#id2695011">Example Configuration</a></span></dt><dd><dl><dt><span class="sect2"><a href="DNSDHCP.html#id2695102">Dynamic DNS</a></span></dt><dt><span class="sect2"><a href="DNSDHCP.html#DHCP">DHCP Server</a></span></dt></dl></dd></dl></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2694832"></a>Features and Benefits</h2></div></div></div><p>
   2 <a class="indexterm" name="id2694840"></a>
   3 <a class="indexterm" name="id2694850"></a>
   4 There are few subjects in the UNIX world that might raise as much contention as
   5 Domain Name System (DNS) and Dynamic Host Configuration Protocol (DHCP).
   6 Not all opinions held for or against particular implementations of DNS and DHCP
   7 are valid.
   8 </p><p>
   9 We live in a modern age where many information technology users demand mobility
  10 and freedom. Microsoft Windows users in particular expect to be able to plug their
  11 notebook computer into a network port and have things &#8220;<span class="quote">just work.</span>&#8221;
  12 </p><p>
  13 <a class="indexterm" name="id2694877"></a>
  14 UNIX administrators have a point. Many of the normative practices in the Microsoft
  15 Windows world at best border on bad practice from a security perspective.
  16 Microsoft Windows networking protocols allow workstations to arbitrarily register
  17 themselves on a network. Windows 2000 Active Directory registers entries in the DNS namespace
  18 that are equally perplexing to UNIX administrators. Welcome to the new world!
  19 </p><p>
  20 <a class="indexterm" name="id2694894"></a>
  21 <a class="indexterm" name="id2694903"></a>
  22 <a class="indexterm" name="id2694912"></a>
  23 The purpose of this chapter is to demonstrate the configuration of the Internet
  24 Software Consortium (ISC) DNS and DHCP servers to provide dynamic services that are
  25 compatible with their equivalents in the Microsoft Windows 2000 Server products.
  26 </p><p>
  27 This chapter provides no more than a working example of configuration files for both DNS and DHCP servers. The
  28 examples used match configuration examples used elsewhere in this document.
  29 </p><p>
  30 <a class="indexterm" name="id2694935"></a>
  31 <a class="indexterm" name="id2694942"></a>
  32 <a class="indexterm" name="id2694948"></a>
  33 This chapter explicitly does not provide a tutorial, nor does it pretend to be a reference guide on DNS and
  34 DHCP, as this is well beyond the scope and intent of this document as a whole. Anyone who wants more detailed
  35 reference materials on DNS or DHCP should visit the ISC Web site at <a href="http://www.isc.org" target="_top"> http://www.isc.org</a>.  Those wanting a written text might also be interested
  36 in the O'Reilly publications on DNS, see the <a href="http://www.oreilly.com/catalog/dns/index.htm" target="_top">O'Reilly</a> web site, and the <a href="http://www.bind9.net/books-dhcp" target="_top">BIND9.NET</a> web site for details.
  37 The books are:
  38 </p><div class="orderedlist"><ol type="1"><li><p>DNS and BIND, By Cricket Liu, Paul Albitz, ISBN: 1-56592-010-4</p></li><li><p>DNS &amp; Bind Cookbook, By Cricket Liu, ISBN: 0-596-00410-9</p></li><li><p>The DHCP Handbook (2nd Edition), By: Ralph Droms, Ted Lemon, ISBN 0-672-32327-3</p></li></ol></div></div><div class="sect1" lang="en"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="id2695011"></a>Example Configuration</h2></div></div></div><p>
  39 <a class="indexterm" name="id2695019"></a>
  40 <a class="indexterm" name="id2695026"></a>
  41 The DNS is to the Internet what water is to life. Nearly all information resources (host names) are resolved
  42 to their Internet protocol (IP) addresses through DNS.  Windows networking tried hard to avoid the
  43 complexities of DNS, but alas, DNS won.  <a class="indexterm" name="id2695037"></a> The alternative to
  44 DNS, the Windows Internet Name Service (WINS)  an artifact of NetBIOS networking over the TCP/IP
  45 protocols  has demonstrated scalability problems as well as a flat, nonhierarchical namespace that
  46 became unmanageable as the size and complexity of information technology networks grew.
  47 </p><p>
  48 <a class="indexterm" name="id2695058"></a>
  49 <a class="indexterm" name="id2695064"></a>
  50 WINS is a Microsoft implementation of the RFC1001/1002 NetBIOS Name Service (NBNS).
  51 It allows NetBIOS clients (like Microsoft Windows machines) to register an arbitrary
  52 machine name that the administrator or user has chosen together with the IP
  53 address that the machine has been given. Through the use of WINS, network client machines
  54 could resolve machine names to their IP address.
  55 </p><p>
  56 The demand for an alternative to the limitations of NetBIOS networking finally drove
  57 Microsoft to use DNS and Active Directory. Microsoft's new implementation attempts
  58 to use DNS in a manner similar to the way that WINS is used for NetBIOS networking.
  59 Both WINS and Microsoft DNS rely on dynamic name registration.
  60 </p><p>
  61 Microsoft Windows clients can perform dynamic name registration to the DNS server
  62 on startup. Alternatively, where DHCP is used to assign workstation IP addresses,
  63 it is possible to register hostnames and their IP address by the DHCP server as
  64 soon as a client acknowledges an IP address lease. Finally, Microsoft DNS can resolve
  65 hostnames via Microsoft WINS.
  66 </p><p>
  67 The following configurations demonstrate a simple, insecure dynamic DNS server and
  68 a simple DHCP server that matches the DNS configuration.
  69 </p><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="id2695102"></a>Dynamic DNS</h3></div></div></div><p>
  70         <a class="indexterm" name="id2695110"></a>
  71         The example DNS configuration is for a private network in the IP address
  72         space for network 192.168.1.0/24. The private class network address space
  73         is set forth in RFC1918.
  74         </p><p>
  75         <a class="indexterm" name="id2695125"></a>
  76         It is assumed that this network will be situated behind a secure firewall.
  77         The files that follow work with ISC BIND version 9. BIND is the Berkeley
  78         Internet Name Daemon.
  79         </p><p>
  80         The master configuration file <code class="filename">/etc/named.conf</code>
  81         determines the location of all further configuration files used.
  82         The location and name of this file is specified in the startup script
  83         that is part of the operating system.
  84 </p><pre class="programlisting">
  85 # Quenya.Org configuration file
  86
  87 acl mynet {
  88         192.168.1.0/24;
  89         127.0.0.1;
  90 };
  91
  92 options {
  93
  94         directory "/var/named";
  95         listen-on-v6 { any; };
  96         notify no;
  97         forward first;
  98         forwarders {
  99                 192.168.1.1;
 100                 };
 101         auth-nxdomain yes;
 102         multiple-cnames yes;
 103         listen-on {
 104                 mynet;
 105                 };
 106 };
 107
 108 # The following three zone definitions do not need any modification.
 109 # The first one defines localhost while the second defines the
 110 # reverse lookup for localhost. The last zone "." is the
 111 # definition of the root name servers.
 112
 113 zone "localhost" in {
 114         type master;
 115         file "localhost.zone";
 116 };
 117
 118 zone "0.0.127.in-addr.arpa" in {
 119         type master;
 120         file "127.0.0.zone";
 121 };
 122
 123 zone "." in {
 124         type hint;
 125         file "root.hint";
 126 };
 127
 128 # You can insert further zone records for your own domains below.
 129
 130 zone "quenya.org" {
 131         type master;
 132         file "/var/named/quenya.org.hosts";
 133         allow-query {
 134                 mynet;
 135                 };
 136         allow-transfer {
 137                 mynet;
 138                 };
 139         allow-update {
 140                 mynet;
 141                 };
 142         };
 143
 144 zone "1.168.192.in-addr.arpa" {
 145         type master;
 146         file "/var/named/192.168.1.0.rev";
 147         allow-query {
 148                 mynet;
 149         };
 150         allow-transfer {
 151                 mynet;
 152         };
 153         allow-update {
 154                 mynet;
 155         };
 156 };
 157 </pre><p>
 158         </p><p>
 159         The following files are all located in the directory <code class="filename">/var/named</code>.
 160         This is the <code class="filename">/var/named/localhost.zone</code> file:
 161 </p><pre class="programlisting">
 162 $TTL 1W
 163 @               IN SOA  @   root (
 164                                 42              ; serial (d. adams)
 165                                 2D              ; refresh
 166                                 4H              ; retry
 167                                 6W              ; expiry
 168                                 1W )            ; minimum
 169
 170                 IN NS           @
 171                 IN A            127.0.0.1
 172         </pre><p>
 173         </p><p>
 174         The <code class="filename">/var/named/127.0.0.zone</code> file:
 175 </p><pre class="programlisting">
 176 $TTL 1W
 177 @               IN SOA          localhost.  root.localhost. (
 178                                 42              ; serial (d. adams)
 179                                 2D              ; refresh
 180                                 4H              ; retry
 181                                 6W              ; expiry
 182                                 1W )            ; minimum
 183
 184                                 IN NS           localhost.
 185 1               IN PTR          localhost.
 186 </pre><p>
 187         </p><p>
 188                 The <code class="filename">/var/named/quenya.org.host</code> file:
 189 </p><pre class="programlisting">
 190 $ORIGIN .
 191 $TTL 38400      ; 10 hours 40 minutes
 192 quenya.org      IN SOA  marvel.quenya.org. root.quenya.org. (
 193                                 2003021832 ; serial
 194                                 10800      ; refresh (3 hours)
 195                                 3600       ; retry (1 hour)
 196                                 604800     ; expire (1 week)
 197                                 38400      ; minimum (10 hours 40 minutes)
 198                                 )
 199                         NS      marvel.quenya.org.
 200                         MX      10 mail.quenya.org.
 201 $ORIGIN quenya.org.
 202 frodo                   A       192.168.1.1
 203 marvel                  A       192.168.1.2
 204 ;
 205 mail                    CNAME   marvel
 206 www                     CNAME   marvel
 207 </pre><p>
 208 </p><p>
 209         The <code class="filename">/var/named/192.168.1.0.rev</code> file:
 210 </p><pre class="programlisting">
 211 $ORIGIN .
 212 $TTL 38400      ; 10 hours 40 minutes
 213 1.168.192.in-addr.arpa  IN SOA  marvel.quenya.org. root.quenya.org. (
 214                                 2003021824 ; serial
 215                                 10800      ; refresh (3 hours)
 216                                 3600       ; retry (1 hour)
 217                                 604800     ; expire (1 week)
 218                                 38400      ; minimum (10 hours 40 minutes)
 219                                 )
 220                         NS      marvel.quenya.org.
 221 $ORIGIN 1.168.192.in-addr.arpa.
 222 1                       PTR     frodo.quenya.org.
 223 2                       PTR     marvel.quenya.org.
 224 </pre><p>
 225         </p><p>
 226 <a class="indexterm" name="id2695277"></a>
 227 <a class="indexterm" name="id2695284"></a>
 228         The configuration files shown here were copied from a fully working system. All dynamically registered
 229         entries have been removed. In addition to these files, BIND version 9 will
 230         create for each of the dynamic registration files a file that has a
 231         <code class="filename">.jnl</code> extension. Do not edit or tamper with the configuration
 232         files or with the <code class="filename">.jnl</code> files that are created.
 233         </p></div><div class="sect2" lang="en"><div class="titlepage"><div><div><h3 class="title"><a name="DHCP"></a>DHCP Server</h3></div></div></div><p>
 234         The following file is used with the ISC DHCP Server version 3.
 235         The file is located in <code class="filename">/etc/dhcpd.conf</code>:
 236         </p><p>
 237         </p><pre class="programlisting">
 238 ddns-updates on;
 239 ddns-domainname "quenya.org";
 240 option ntp-servers 192.168.1.2;
 241 ddns-update-style ad-hoc;
 242 allow unknown-clients;
 243 default-lease-time 86400;
 244 max-lease-time 172800;
 245
 246 option domain-name "quenya.org";
 247 option domain-name-servers 192.168.1.2;
 248 option netbios-name-servers 192.168.1.2;
 249 option netbios-dd-server 192.168.1.2;
 250 option netbios-node-type 8;
 251
 252 subnet 192.168.1.0 netmask 255.255.255.0 {
 253         range dynamic-bootp 192.168.1.60 192.168.1.254;
 254         option subnet-mask 255.255.255.0;
 255         option routers 192.168.1.2;
 256         allow unknown-clients;
 257 }
 258 </pre><p>
 259         </p><p>
 260         In this example, IP addresses between 192.168.1.1 and 192.168.1.59 are
 261         reserved for fixed-address (commonly called <code class="constant">hard-wired</code>) IP addresses. The
 262         addresses between 192.168.1.60 and 192.168.1.254 are allocated for dynamic use.
 263         </p></div></div></div><div class="navfooter"><hr><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="ch46.html">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="Appendix.html">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="gpl.html">Next</a></td></tr><tr><td width="40%" align="left" valign="top">Chapter 46. Samba Support </td><td width="20%" align="center"><a accesskey="h" href="index.html">Home</a></td><td width="40%" align="right" valign="top"> Appendix A. GNU General Public License</td></tr></table></div></body></html>