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  30 <tr><th colspan="3" align="center">Chapter 3. Name Server Configuration</th></tr>
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  41 <div class="chapter">
  42 <div class="titlepage"><div><div><h1 class="title">
  43 <a name="Bv9ARM.ch03"></a>Chapter 3. Name Server Configuration</h1></div></div></div>
  44 <div class="toc">
  45 <p><b>Table of Contents</b></p>
  46 <dl class="toc">
  47 <dt><span class="section"><a href="Bv9ARM.ch03.html#sample_configuration">Sample Configurations</a></span></dt>
  48 <dd><dl>
  49 <dt><span class="section"><a href="Bv9ARM.ch03.html#cache_only_sample">A Caching-only Name Server</a></span></dt>
  50 <dt><span class="section"><a href="Bv9ARM.ch03.html#auth_only_sample">An Authoritative-only Name Server</a></span></dt>
  51 </dl></dd>
  52 <dt><span class="section"><a href="Bv9ARM.ch03.html#load_balancing">Load Balancing</a></span></dt>
  53 <dt><span class="section"><a href="Bv9ARM.ch03.html#ns_operations">Name Server Operations</a></span></dt>
  54 <dd><dl>
  55 <dt><span class="section"><a href="Bv9ARM.ch03.html#tools">Tools for Use With the Name Server Daemon</a></span></dt>
  56 <dt><span class="section"><a href="Bv9ARM.ch03.html#signals">Signals</a></span></dt>
  57 </dl></dd>
  58 </dl>
  59 </div>
  60 <p>
  61       In this chapter we provide some suggested configurations along
  62       with guidelines for their use.  We suggest reasonable values for
  63       certain option settings.
  64     </p>
  65 <div class="section">
  66 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
  67 <a name="sample_configuration"></a>Sample Configurations</h2></div></div></div>
  68 <div class="section">
  69 <div class="titlepage"><div><div><h3 class="title">
  70 <a name="cache_only_sample"></a>A Caching-only Name Server</h3></div></div></div>
  71 <p>
  72           The following sample configuration is appropriate for a caching-only
  73           name server for use by clients internal to a corporation.  All
  74           queries
  75           from outside clients are refused using the <span class="command"><strong>allow-query</strong></span>
  76           option.  Alternatively, the same effect could be achieved using
  77           suitable
  78           firewall rules.
  79         </p>
  80 <pre class="programlisting">
  81 // Two corporate subnets we wish to allow queries from.
  82 acl corpnets { 192.168.4.0/24; 192.168.7.0/24; };
  83 options {
  84      // Working directory
  85      directory "/etc/namedb";
  86
  87      allow-query { corpnets; };
  88 };
  89 // Provide a reverse mapping for the loopback
  90 // address 127.0.0.1
  91 zone "0.0.127.in-addr.arpa" {
  92      type master;
  93      file "localhost.rev";
  94      notify no;
  95 };
  96 </pre>
  97 </div>
  98 <div class="section">
  99 <div class="titlepage"><div><div><h3 class="title">
 100 <a name="auth_only_sample"></a>An Authoritative-only Name Server</h3></div></div></div>
 101 <p>
 102           This sample configuration is for an authoritative-only server
 103           that is the master server for "<code class="filename">example.com</code>"
 104           and a slave for the subdomain "<code class="filename">eng.example.com</code>".
 105         </p>
 106 <pre class="programlisting">
 107 options {
 108      // Working directory
 109      directory "/etc/namedb";
 110      // Do not allow access to cache
 111      allow-query-cache { none; };
 112      // This is the default
 113      allow-query { any; };
 114      // Do not provide recursive service
 115      recursion no;
 116 };
 117
 118 // Provide a reverse mapping for the loopback
 119 // address 127.0.0.1
 120 zone "0.0.127.in-addr.arpa" {
 121      type master;
 122      file "localhost.rev";
 123      notify no;
 124 };
 125 // We are the master server for example.com
 126 zone "example.com" {
 127      type master;
 128      file "example.com.db";
 129      // IP addresses of slave servers allowed to
 130      // transfer example.com
 131      allow-transfer {
 132           192.168.4.14;
 133           192.168.5.53;
 134      };
 135 };
 136 // We are a slave server for eng.example.com
 137 zone "eng.example.com" {
 138      type slave;
 139      file "eng.example.com.bk";
 140      // IP address of eng.example.com master server
 141      masters { 192.168.4.12; };
 142 };
 143 </pre>
 144 </div>
 145 </div>
 146 <div class="section">
 147 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
 148 <a name="load_balancing"></a>Load Balancing</h2></div></div></div>
 149 <p>
 150         A primitive form of load balancing can be achieved in
 151         the <acronym class="acronym">DNS</acronym> by using multiple records
 152         (such as multiple A records) for one name.
 153       </p>
 154 <p>
 155         For example, if you have three WWW servers with network addresses
 156         of 10.0.0.1, 10.0.0.2 and 10.0.0.3, a set of records such as the
 157         following means that clients will connect to each machine one third
 158         of the time:
 159       </p>
 160 <div class="informaltable"><table border="1">
 161 <colgroup>
 162 <col width="0.875in" class="1">
 163 <col width="0.500in" class="2">
 164 <col width="0.750in" class="3">
 165 <col width="0.750in" class="4">
 166 <col width="2.028in" class="5">
 167 </colgroup>
 168 <tbody>
 169 <tr>
 170 <td>
 171                 <p>
 172                   Name
 173                 </p>
 174               </td>
 175 <td>
 176                 <p>
 177                   TTL
 178                 </p>
 179               </td>
 180 <td>
 181                 <p>
 182                   CLASS
 183                 </p>
 184               </td>
 185 <td>
 186                 <p>
 187                   TYPE
 188                 </p>
 189               </td>
 190 <td>
 191                 <p>
 192                   Resource Record (RR) Data
 193                 </p>
 194               </td>
 195 </tr>
 196 <tr>
 197 <td>
 198                 <p>
 199                   <code class="literal">www</code>
 200                 </p>
 201               </td>
 202 <td>
 203                 <p>
 204                   <code class="literal">600</code>
 205                 </p>
 206               </td>
 207 <td>
 208                 <p>
 209                   <code class="literal">IN</code>
 210                 </p>
 211               </td>
 212 <td>
 213                 <p>
 214                   <code class="literal">A</code>
 215                 </p>
 216               </td>
 217 <td>
 218                 <p>
 219                   <code class="literal">10.0.0.1</code>
 220                 </p>
 221               </td>
 222 </tr>
 223 <tr>
 224 <td>
 225                 <p></p>
 226               </td>
 227 <td>
 228                 <p>
 229                   <code class="literal">600</code>
 230                 </p>
 231               </td>
 232 <td>
 233                 <p>
 234                   <code class="literal">IN</code>
 235                 </p>
 236               </td>
 237 <td>
 238                 <p>
 239                   <code class="literal">A</code>
 240                 </p>
 241               </td>
 242 <td>
 243                 <p>
 244                   <code class="literal">10.0.0.2</code>
 245                 </p>
 246               </td>
 247 </tr>
 248 <tr>
 249 <td>
 250                 <p></p>
 251               </td>
 252 <td>
 253                 <p>
 254                   <code class="literal">600</code>
 255                 </p>
 256               </td>
 257 <td>
 258                 <p>
 259                   <code class="literal">IN</code>
 260                 </p>
 261               </td>
 262 <td>
 263                 <p>
 264                   <code class="literal">A</code>
 265                 </p>
 266               </td>
 267 <td>
 268                 <p>
 269                   <code class="literal">10.0.0.3</code>
 270                 </p>
 271               </td>
 272 </tr>
 273 </tbody>
 274 </table></div>
 275 <p>
 276         When a resolver queries for these records, <acronym class="acronym">BIND</acronym> will rotate
 277         them and respond to the query with the records in a different
 278         order.  In the example above, clients will randomly receive
 279         records in the order 1, 2, 3; 2, 3, 1; and 3, 1, 2. Most clients
 280         will use the first record returned and discard the rest.
 281       </p>
 282 <p>
 283         For more detail on ordering responses, check the
 284         <span class="command"><strong>rrset-order</strong></span> sub-statement in the
 285         <span class="command"><strong>options</strong></span> statement, see
 286         <a class="xref" href="Bv9ARM.ch06.html#rrset_ordering" title="RRset Ordering">RRset Ordering</a>.
 287       </p>
 288 </div>
 289 <div class="section">
 290 <div class="titlepage"><div><div><h2 class="title" style="clear: both">
 291 <a name="ns_operations"></a>Name Server Operations</h2></div></div></div>
 292 <div class="section">
 293 <div class="titlepage"><div><div><h3 class="title">
 294 <a name="tools"></a>Tools for Use With the Name Server Daemon</h3></div></div></div>
 295 <p>
 296           This section describes several indispensable diagnostic,
 297           administrative and monitoring tools available to the system
 298           administrator for controlling and debugging the name server
 299           daemon.
 300         </p>
 301 <div class="section">
 302 <div class="titlepage"><div><div><h4 class="title">
 303 <a name="diagnostic_tools"></a>Diagnostic Tools</h4></div></div></div>
 304 <p>
 305             The <span class="command"><strong>dig</strong></span>, <span class="command"><strong>host</strong></span>, and
 306             <span class="command"><strong>nslookup</strong></span> programs are all command
 307             line tools
 308             for manually querying name servers.  They differ in style and
 309             output format.
 310           </p>
 311 <div class="variablelist"><dl class="variablelist">
 312 <dt><span class="term"><a name="dig"></a><span class="command"><strong>dig</strong></span></span></dt>
 313 <dd>
 314 <p>
 315                   The domain information groper (<span class="command"><strong>dig</strong></span>)
 316                   is the most versatile and complete of these lookup tools.
 317                   It has two modes: simple interactive
 318                   mode for a single query, and batch mode which executes a
 319                   query for
 320                   each in a list of several query lines. All query options are
 321                   accessible
 322                   from the command line.
 323                 </p>
 324 <div class="cmdsynopsis"><p><code class="command">dig</code>  [@<em class="replaceable"><code>server</code></em>]  <em class="replaceable"><code>domain</code></em>  [<em class="replaceable"><code>query-type</code></em>] [<em class="replaceable"><code>query-class</code></em>] [+<em class="replaceable"><code>query-option</code></em>] [-<em class="replaceable"><code>dig-option</code></em>] [%<em class="replaceable"><code>comment</code></em>]</p></div>
 325 <p>
 326                   The usual simple use of <span class="command"><strong>dig</strong></span> will take the form
 327                 </p>
 328 <p class="simpara">
 329                   <span class="command"><strong>dig @server domain query-type query-class</strong></span>
 330                 </p>
 331 <p>
 332                   For more information and a list of available commands and
 333                   options, see the <span class="command"><strong>dig</strong></span> man
 334                   page.
 335                 </p>
 336 </dd>
 337 <dt><span class="term"><span class="command"><strong>host</strong></span></span></dt>
 338 <dd>
 339 <p>
 340                   The <span class="command"><strong>host</strong></span> utility emphasizes
 341                   simplicity
 342                   and ease of use.  By default, it converts
 343                   between host names and Internet addresses, but its
 344                   functionality
 345                   can be extended with the use of options.
 346                 </p>
 347 <div class="cmdsynopsis"><p><code class="command">host</code>  [-aCdlnrsTwv] [-c <em class="replaceable"><code>class</code></em>] [-N <em class="replaceable"><code>ndots</code></em>] [-t <em class="replaceable"><code>type</code></em>] [-W <em class="replaceable"><code>timeout</code></em>] [-R <em class="replaceable"><code>retries</code></em>] [-m <em class="replaceable"><code>flag</code></em>] [-4] [-6]  <em class="replaceable"><code>hostname</code></em>  [<em class="replaceable"><code>server</code></em>]</p></div>
 348 <p>
 349                   For more information and a list of available commands and
 350                   options, see the <span class="command"><strong>host</strong></span> man
 351                   page.
 352                 </p>
 353 </dd>
 354 <dt><span class="term"><span class="command"><strong>nslookup</strong></span></span></dt>
 355 <dd>
 356 <p><span class="command"><strong>nslookup</strong></span>
 357                   has two modes: interactive and
 358                   non-interactive. Interactive mode allows the user to
 359                   query name servers for information about various
 360                   hosts and domains or to print a list of hosts in a
 361                   domain. Non-interactive mode is used to print just
 362                   the name and requested information for a host or
 363                   domain.
 364                 </p>
 365 <div class="cmdsynopsis"><p><code class="command">nslookup</code>  [-option...] [[<em class="replaceable"><code>host-to-find</code></em>] |  [- [server]]]</p></div>
 366 <p>
 367                   Interactive mode is entered when no arguments are given (the
 368                   default name server will be used) or when the first argument
 369                   is a
 370                   hyphen (`-') and the second argument is the host name or
 371                   Internet address
 372                   of a name server.
 373                 </p>
 374 <p>
 375                   Non-interactive mode is used when the name or Internet
 376                   address
 377                   of the host to be looked up is given as the first argument.
 378                   The
 379                   optional second argument specifies the host name or address
 380                   of a name server.
 381                 </p>
 382 <p>
 383                   Due to its arcane user interface and frequently inconsistent
 384                   behavior, we do not recommend the use of <span class="command"><strong>nslookup</strong></span>.
 385                   Use <span class="command"><strong>dig</strong></span> instead.
 386                 </p>
 387 </dd>
 388 </dl></div>
 389 </div>
 390 <div class="section">
 391 <div class="titlepage"><div><div><h4 class="title">
 392 <a name="admin_tools"></a>Administrative Tools</h4></div></div></div>
 393 <p>
 394             Administrative tools play an integral part in the management
 395             of a server.
 396           </p>
 397 <div class="variablelist"><dl class="variablelist">
 398 <dt>
 399 <a name="named-checkconf"></a><span class="term"><span class="command"><strong>named-checkconf</strong></span></span>
 400 </dt>
 401 <dd>
 402 <p>
 403                   The <span class="command"><strong>named-checkconf</strong></span> program
 404                   checks the syntax of a <code class="filename">named.conf</code> file.
 405                 </p>
 406 <div class="cmdsynopsis"><p><code class="command">named-checkconf</code>  [-jvz] [-t <em class="replaceable"><code>directory</code></em>] [<em class="replaceable"><code>filename</code></em>]</p></div>
 407 </dd>
 408 <dt>
 409 <a name="named-checkzone"></a><span class="term"><span class="command"><strong>named-checkzone</strong></span></span>
 410 </dt>
 411 <dd>
 412 <p>
 413                   The <span class="command"><strong>named-checkzone</strong></span> program
 414                   checks a master file for
 415                   syntax and consistency.
 416                 </p>
 417 <div class="cmdsynopsis"><p><code class="command">named-checkzone</code>  [-djqvD] [-c <em class="replaceable"><code>class</code></em>] [-o <em class="replaceable"><code>output</code></em>] [-t <em class="replaceable"><code>directory</code></em>] [-w <em class="replaceable"><code>directory</code></em>] [-k <em class="replaceable"><code>(ignore|warn|fail)</code></em>] [-n <em class="replaceable"><code>(ignore|warn|fail)</code></em>] [-W <em class="replaceable"><code>(ignore|warn)</code></em>]  <em class="replaceable"><code>zone</code></em>  [<em class="replaceable"><code>filename</code></em>]</p></div>
 418 </dd>
 419 <dt>
 420 <a name="named-compilezone"></a><span class="term"><span class="command"><strong>named-compilezone</strong></span></span>
 421 </dt>
 422 <dd><p>
 423                   Similar to <span class="command"><strong>named-checkzone,</strong></span> but
 424                   it always dumps the zone content to a specified file
 425                   (typically in a different format).
 426                 </p></dd>
 427 <dt>
 428 <a name="rndc"></a><span class="term"><span class="command"><strong>rndc</strong></span></span>
 429 </dt>
 430 <dd>
 431 <p>
 432                   The remote name daemon control
 433                   (<span class="command"><strong>rndc</strong></span>) program allows the
 434                   system
 435                   administrator to control the operation of a name server.
 436                   Since <acronym class="acronym">BIND</acronym> 9.2, <span class="command"><strong>rndc</strong></span>
 437                   supports all the commands of the BIND 8 <span class="command"><strong>ndc</strong></span>
 438                   utility except <span class="command"><strong>ndc start</strong></span> and
 439                   <span class="command"><strong>ndc restart</strong></span>, which were also
 440                   not supported in <span class="command"><strong>ndc</strong></span>'s
 441                   channel mode.
 442                   If you run <span class="command"><strong>rndc</strong></span> without any
 443                   options
 444                   it will display a usage message as follows:
 445                 </p>
 446 <div class="cmdsynopsis"><p><code class="command">rndc</code>  [-c <em class="replaceable"><code>config</code></em>] [-s <em class="replaceable"><code>server</code></em>] [-p <em class="replaceable"><code>port</code></em>] [-y <em class="replaceable"><code>key</code></em>]  <em class="replaceable"><code>command</code></em>  [<em class="replaceable"><code>command</code></em>...]</p></div>
 447 <p>See <a class="xref" href="man.rndc.html" title="rndc"><span class="refentrytitle"><span class="application">rndc</span></span>(8)</a> for details of
 448                   the available <span class="command"><strong>rndc</strong></span> commands.
 449                 </p>
 450 <p>
 451                   <span class="command"><strong>rndc</strong></span> requires a configuration file,
 452                   since all
 453                   communication with the server is authenticated with
 454                   digital signatures that rely on a shared secret, and
 455                   there is no way to provide that secret other than with a
 456                   configuration file.  The default location for the
 457                   <span class="command"><strong>rndc</strong></span> configuration file is
 458                   <code class="filename">/etc/rndc.conf</code>, but an
 459                   alternate
 460                   location can be specified with the <code class="option">-c</code>
 461                   option.  If the configuration file is not found,
 462                   <span class="command"><strong>rndc</strong></span> will also look in
 463                   <code class="filename">/etc/rndc.key</code> (or whatever
 464                   <code class="varname">sysconfdir</code> was defined when
 465                   the <acronym class="acronym">BIND</acronym> build was
 466                   configured).
 467                   The <code class="filename">rndc.key</code> file is
 468                   generated by
 469                   running <span class="command"><strong>rndc-confgen -a</strong></span> as
 470                   described in
 471                   <a class="xref" href="Bv9ARM.ch06.html#controls_statement_definition_and_usage" title="controls Statement Definition and Usage">the section called &#8220;<span class="command"><strong>controls</strong></span> Statement Definition and
 472           Usage&#8221;</a>.
 473                 </p>
 474 <p>
 475                   The format of the configuration file is similar to
 476                   that of <code class="filename">named.conf</code>, but
 477                   limited to
 478                   only four statements, the <span class="command"><strong>options</strong></span>,
 479                   <span class="command"><strong>key</strong></span>, <span class="command"><strong>server</strong></span> and
 480                   <span class="command"><strong>include</strong></span>
 481                   statements.  These statements are what associate the
 482                   secret keys to the servers with which they are meant to
 483                   be shared.  The order of statements is not
 484                   significant.
 485                 </p>
 486 <p>
 487                   The <span class="command"><strong>options</strong></span> statement has
 488                   three clauses:
 489                   <span class="command"><strong>default-server</strong></span>, <span class="command"><strong>default-key</strong></span>,
 490                   and <span class="command"><strong>default-port</strong></span>.
 491                   <span class="command"><strong>default-server</strong></span> takes a
 492                   host name or address argument  and represents the server
 493                   that will
 494                   be contacted if no <code class="option">-s</code>
 495                   option is provided on the command line.
 496                   <span class="command"><strong>default-key</strong></span> takes
 497                   the name of a key as its argument, as defined by a <span class="command"><strong>key</strong></span> statement.
 498                   <span class="command"><strong>default-port</strong></span> specifies the
 499                   port to which
 500                   <span class="command"><strong>rndc</strong></span> should connect if no
 501                   port is given on the command line or in a
 502                   <span class="command"><strong>server</strong></span> statement.
 503                 </p>
 504 <p>
 505                   The <span class="command"><strong>key</strong></span> statement defines a
 506                   key to be used
 507                   by <span class="command"><strong>rndc</strong></span> when authenticating
 508                   with
 509                   <span class="command"><strong>named</strong></span>.  Its syntax is
 510                   identical to the
 511                   <span class="command"><strong>key</strong></span> statement in <code class="filename">named.conf</code>.
 512                   The keyword <strong class="userinput"><code>key</code></strong> is
 513                   followed by a key name, which must be a valid
 514                   domain name, though it need not actually be hierarchical;
 515                   thus,
 516                   a string like "<strong class="userinput"><code>rndc_key</code></strong>" is a valid
 517                   name.
 518                   The <span class="command"><strong>key</strong></span> statement has two
 519                   clauses:
 520                   <span class="command"><strong>algorithm</strong></span> and <span class="command"><strong>secret</strong></span>.
 521                   While the configuration parser will accept any string as the
 522                   argument
 523                   to algorithm, currently only the string "<strong class="userinput"><code>hmac-md5</code></strong>"
 524                   has any meaning.  The secret is a base-64 encoded string
 525                   as specified in RFC 3548.
 526                 </p>
 527 <p>
 528                   The <span class="command"><strong>server</strong></span> statement
 529                   associates a key
 530                   defined using the <span class="command"><strong>key</strong></span>
 531                   statement with a server.
 532                   The keyword <strong class="userinput"><code>server</code></strong> is followed by a
 533                   host name or address.  The <span class="command"><strong>server</strong></span> statement
 534                   has two clauses: <span class="command"><strong>key</strong></span> and <span class="command"><strong>port</strong></span>.
 535                   The <span class="command"><strong>key</strong></span> clause specifies the
 536                   name of the key
 537                   to be used when communicating with this server, and the
 538                   <span class="command"><strong>port</strong></span> clause can be used to
 539                   specify the port <span class="command"><strong>rndc</strong></span> should
 540                   connect
 541                   to on the server.
 542                 </p>
 543 <p>
 544                   A sample minimal configuration file is as follows:
 545                 </p>
 546 <pre class="programlisting">
 547 key rndc_key {
 548      algorithm "hmac-md5";
 549      secret
 550        "c3Ryb25nIGVub3VnaCBmb3IgYSBtYW4gYnV0IG1hZGUgZm9yIGEgd29tYW4K";
 551 };
 552 options {
 553      default-server 127.0.0.1;
 554      default-key    rndc_key;
 555 };
 556 </pre>
 557 <p>
 558                   This file, if installed as <code class="filename">/etc/rndc.conf</code>,
 559                   would allow the command:
 560                 </p>
 561 <p>
 562                   <code class="prompt">$ </code><strong class="userinput"><code>rndc reload</code></strong>
 563                 </p>
 564 <p>
 565                   to connect to 127.0.0.1 port 953 and cause the name server
 566                   to reload, if a name server on the local machine were
 567                   running with
 568                   following controls statements:
 569                 </p>
 570 <pre class="programlisting">
 571 controls {
 572         inet 127.0.0.1
 573             allow { localhost; } keys { rndc_key; };
 574 };
 575 </pre>
 576 <p>
 577                   and it had an identical key statement for
 578                   <code class="literal">rndc_key</code>.
 579                 </p>
 580 <p>
 581                   Running the <span class="command"><strong>rndc-confgen</strong></span>
 582                   program will
 583                   conveniently create a <code class="filename">rndc.conf</code>
 584                   file for you, and also display the
 585                   corresponding <span class="command"><strong>controls</strong></span>
 586                   statement that you need to
 587                   add to <code class="filename">named.conf</code>.
 588                   Alternatively,
 589                   you can run <span class="command"><strong>rndc-confgen -a</strong></span>
 590                   to set up
 591                   a <code class="filename">rndc.key</code> file and not
 592                   modify
 593                   <code class="filename">named.conf</code> at all.
 594                 </p>
 595 </dd>
 596 </dl></div>
 597 </div>
 598 </div>
 599 <div class="section">
 600 <div class="titlepage"><div><div><h3 class="title">
 601 <a name="signals"></a>Signals</h3></div></div></div>
 602 <p>
 603           Certain UNIX signals cause the name server to take specific
 604           actions, as described in the following table.  These signals can
 605           be sent using the <span class="command"><strong>kill</strong></span> command.
 606         </p>
 607 <div class="informaltable"><table border="1">
 608 <colgroup>
 609 <col width="1.125in" class="1">
 610 <col width="4.000in" class="2">
 611 </colgroup>
 612 <tbody>
 613 <tr>
 614 <td>
 615                   <p><span class="command"><strong>SIGHUP</strong></span></p>
 616                 </td>
 617 <td>
 618                   <p>
 619                     Causes the server to read <code class="filename">named.conf</code> and
 620                     reload the database.
 621                   </p>
 622                 </td>
 623 </tr>
 624 <tr>
 625 <td>
 626                   <p><span class="command"><strong>SIGTERM</strong></span></p>
 627                 </td>
 628 <td>
 629                   <p>
 630                     Causes the server to clean up and exit.
 631                   </p>
 632                 </td>
 633 </tr>
 634 <tr>
 635 <td>
 636                   <p><span class="command"><strong>SIGINT</strong></span></p>
 637                 </td>
 638 <td>
 639                   <p>
 640                     Causes the server to clean up and exit.
 641                   </p>
 642                 </td>
 643 </tr>
 644 </tbody>
 645 </table></div>
 646 </div>
 647 </div>
 648 </div>
 649 <div class="navfooter">
 650 <hr>
 651 <table width="100%" summary="Navigation footer">
 652 <tr>
 653 <td width="40%" align="left">
 654 <a accesskey="p" href="Bv9ARM.ch02.html">Prev</a> </td>
 655 <td width="20%" align="center"> </td>
 656 <td width="40%" align="right"> <a accesskey="n" href="Bv9ARM.ch04.html">Next</a>
 657 </td>
 658 </tr>
 659 <tr>
 660 <td width="40%" align="left" valign="top">Chapter 2. <acronym class="acronym">BIND</acronym> Resource Requirements </td>
 661 <td width="20%" align="center"><a accesskey="h" href="Bv9ARM.html">Home</a></td>
 662 <td width="40%" align="right" valign="top"> Chapter 4. Advanced DNS Features</td>
 663 </tr>
 664 </table>
 665 </div>
 666 <p xmlns:db="http://docbook.org/ns/docbook" style="text-align: center;">BIND 9.9.9-P4 (Extended Support Version)</p>
 667 </body>
 668 </html>