contrib/bind9/bin/named/lwresd.docbook

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  20
  21 <!-- $Id: lwresd.docbook,v 1.7.18.10 2008/10/16 23:46:00 tbox Exp $ -->
  22 <refentry>
  23   <refentryinfo>
  24     <date>June 30, 2000</date>
  25   </refentryinfo>
  26
  27   <refmeta>
  28     <refentrytitle><application>lwresd</application></refentrytitle>
  29     <manvolnum>8</manvolnum>
  30     <refmiscinfo>BIND9</refmiscinfo>
  31   </refmeta>
  32
  33   <refnamediv>
  34     <refname><application>lwresd</application></refname>
  35     <refpurpose>lightweight resolver daemon</refpurpose>
  36   </refnamediv>
  37
  38   <docinfo>
  39     <copyright>
  40       <year>2004</year>
  41       <year>2005</year>
  42       <year>2007</year>
  43       <year>2008</year>
  44       <holder>Internet Systems Consortium, Inc. ("ISC")</holder>
  45     </copyright>
  46     <copyright>
  47       <year>2000</year>
  48       <year>2001</year>
  49       <holder>Internet Software Consortium.</holder>
  50     </copyright>
  51   </docinfo>
  52
  53   <refsynopsisdiv>
  54     <cmdsynopsis>
  55       <command>lwresd</command>
  56       <arg><option>-c <replaceable class="parameter">config-file</replaceable></option></arg>
  57       <arg><option>-C <replaceable class="parameter">config-file</replaceable></option></arg>
  58       <arg><option>-d <replaceable class="parameter">debug-level</replaceable></option></arg>
  59       <arg><option>-f</option></arg>
  60       <arg><option>-g</option></arg>
  61       <arg><option>-i <replaceable class="parameter">pid-file</replaceable></option></arg>
  62       <arg><option>-m <replaceable class="parameter">flag</replaceable></option></arg>
  63       <arg><option>-n <replaceable class="parameter">#cpus</replaceable></option></arg>
  64       <arg><option>-P <replaceable class="parameter">port</replaceable></option></arg>
  65       <arg><option>-p <replaceable class="parameter">port</replaceable></option></arg>
  66       <arg><option>-s</option></arg>
  67       <arg><option>-t <replaceable class="parameter">directory</replaceable></option></arg>
  68       <arg><option>-u <replaceable class="parameter">user</replaceable></option></arg>
  69       <arg><option>-v</option></arg>
  70       <arg><option>-4</option></arg>
  71       <arg><option>-6</option></arg>
  72     </cmdsynopsis>
  73   </refsynopsisdiv>
  74
  75   <refsect1>
  76     <title>DESCRIPTION</title>
  77
  78     <para><command>lwresd</command>
  79       is the daemon providing name lookup
  80       services to clients that use the BIND 9 lightweight resolver
  81       library.  It is essentially a stripped-down, caching-only name
  82       server that answers queries using the BIND 9 lightweight
  83       resolver protocol rather than the DNS protocol.
  84     </para>
  85
  86     <para><command>lwresd</command>
  87       listens for resolver queries on a
  88       UDP port on the IPv4 loopback interface, 127.0.0.1.  This
  89       means that <command>lwresd</command> can only be used by
  90       processes running on the local machine.  By default UDP port
  91       number 921 is used for lightweight resolver requests and
  92       responses.
  93     </para>
  94     <para>
  95       Incoming lightweight resolver requests are decoded by the
  96       server which then resolves them using the DNS protocol.  When
  97       the DNS lookup completes, <command>lwresd</command> encodes
  98       the answers in the lightweight resolver format and returns
  99       them to the client that made the request.
 100     </para>
 101     <para>
 102       If <filename>/etc/resolv.conf</filename> contains any
 103       <option>nameserver</option> entries, <command>lwresd</command>
 104       sends recursive DNS queries to those servers.  This is similar
 105       to the use of forwarders in a caching name server.  If no
 106       <option>nameserver</option> entries are present, or if
 107       forwarding fails, <command>lwresd</command> resolves the
 108       queries autonomously starting at the root name servers, using
 109       a built-in list of root server hints.
 110     </para>
 111   </refsect1>
 112
 113   <refsect1>
 114     <title>OPTIONS</title>
 115
 116     <variablelist>
 117
 118       <varlistentry>
 119         <term>-4</term>
 120         <listitem>
 121           <para>
 122             Use IPv4 only even if the host machine is capable of IPv6.
 123             <option>-4</option> and <option>-6</option> are mutually
 124             exclusive.
 125           </para>
 126         </listitem>
 127       </varlistentry>
 128
 129       <varlistentry>
 130         <term>-6</term>
 131         <listitem>
 132           <para>
 133             Use IPv6 only even if the host machine is capable of IPv4.
 134             <option>-4</option> and <option>-6</option> are mutually
 135             exclusive.
 136           </para>
 137         </listitem>
 138       </varlistentry>
 139
 140       <!-- this is in source but not mentioned? does this matter? -->
 141       <varlistentry>
 142         <term>-c <replaceable class="parameter">config-file</replaceable></term>
 143         <listitem>
 144           <para>
 145             Use <replaceable class="parameter">config-file</replaceable> as the
 146             configuration file instead of the default,
 147             <filename>/etc/lwresd.conf</filename>.
 148             <!-- Should this be an absolute path name? -->
 149             <option>-c</option> can not be used with <option>-C</option>.
 150           </para>
 151         </listitem>
 152       </varlistentry>
 153
 154       <varlistentry>
 155         <term>-C <replaceable class="parameter">config-file</replaceable></term>
 156         <listitem>
 157           <para>
 158             Use <replaceable class="parameter">config-file</replaceable> as the
 159             configuration file instead of the default,
 160             <filename>/etc/resolv.conf</filename>.
 161             <option>-C</option> can not be used with <option>-c</option>.
 162           </para>
 163         </listitem>
 164       </varlistentry>
 165
 166       <varlistentry>
 167         <term>-d <replaceable class="parameter">debug-level</replaceable></term>
 168         <listitem>
 169           <para>
 170             Set the daemon's debug level to <replaceable class="parameter">debug-level</replaceable>.
 171             Debugging traces from <command>lwresd</command> become
 172                         more verbose as the debug level increases.
 173           </para>
 174         </listitem>
 175       </varlistentry>
 176
 177       <varlistentry>
 178         <term>-f</term>
 179         <listitem>
 180           <para>
 181             Run the server in the foreground (i.e. do not daemonize).
 182           </para>
 183         </listitem>
 184       </varlistentry>
 185
 186       <varlistentry>
 187         <term>-g</term>
 188         <listitem>
 189           <para>
 190             Run the server in the foreground and force all logging
 191             to <filename>stderr</filename>.
 192           </para>
 193         </listitem>
 194       </varlistentry>
 195
 196       <varlistentry>
 197         <term>-i <replaceable class="parameter">pid-file</replaceable></term>
 198         <listitem>
 199           <para>
 200             Use <replaceable class="parameter">pid-file</replaceable> as the
 201             PID file instead of the default,
 202             <filename>/var/run/lwresd.pid</filename>.
 203           </para>
 204         </listitem>
 205       </varlistentry>
 206
 207       <varlistentry>
 208         <term>-m <replaceable class="parameter">flag</replaceable></term>
 209         <listitem>
 210           <para>
 211             Turn on memory usage debugging flags.  Possible flags are
 212             <replaceable class="parameter">usage</replaceable>,
 213             <replaceable class="parameter">trace</replaceable>,
 214             <replaceable class="parameter">record</replaceable>,
 215             <replaceable class="parameter">size</replaceable>, and
 216             <replaceable class="parameter">mctx</replaceable>.
 217             These correspond to the ISC_MEM_DEBUGXXXX flags described in
 218             <filename>&lt;isc/mem.h&gt;</filename>.
 219           </para>
 220         </listitem>
 221       </varlistentry>
 222
 223       <varlistentry>
 224         <term>-n <replaceable class="parameter">#cpus</replaceable></term>
 225         <listitem>
 226           <para>
 227             Create <replaceable class="parameter">#cpus</replaceable> worker threads
 228             to take advantage of multiple CPUs.  If not specified,
 229             <command>lwresd</command> will try to determine the
 230             number of CPUs present and create one thread per CPU.
 231             If it is unable to determine the number of CPUs, a
 232             single worker thread will be created.
 233           </para>
 234         </listitem>
 235       </varlistentry>
 236
 237       <varlistentry>
 238         <term>-P <replaceable class="parameter">port</replaceable></term>
 239         <listitem>
 240           <para>
 241             Listen for lightweight resolver queries on port
 242             <replaceable class="parameter">port</replaceable>.  If
 243                         not specified, the default is port 921.
 244           </para>
 245         </listitem>
 246       </varlistentry>
 247
 248       <varlistentry>
 249         <term>-p <replaceable class="parameter">port</replaceable></term>
 250         <listitem>
 251           <para>
 252             Send DNS lookups to port <replaceable class="parameter">port</replaceable>.  If not
 253             specified, the default is port 53.  This provides a
 254             way of testing the lightweight resolver daemon with a
 255             name server that listens for queries on a non-standard
 256             port number.
 257           </para>
 258         </listitem>
 259       </varlistentry>
 260
 261       <varlistentry>
 262         <term>-s</term>
 263         <listitem>
 264           <para>
 265             Write memory usage statistics to <filename>stdout</filename>
 266             on exit.
 267           </para>
 268           <note>
 269             <para>
 270               This option is mainly of interest to BIND 9 developers
 271               and may be removed or changed in a future release.
 272             </para>
 273           </note>
 274         </listitem>
 275       </varlistentry>
 276
 277       <varlistentry>
 278         <term>-t <replaceable class="parameter">directory</replaceable></term>
 279         <listitem>
 280           <para>Chroot
 281             to <replaceable class="parameter">directory</replaceable> after
 282             processing the command line arguments, but before
 283             reading the configuration file.
 284           </para>
 285           <warning>
 286             <para>
 287               This option should be used in conjunction with the
 288               <option>-u</option> option, as chrooting a process
 289               running as root doesn't enhance security on most
 290               systems; the way <function>chroot(2)</function> is
 291               defined allows a process with root privileges to
 292               escape a chroot jail.
 293             </para>
 294           </warning>
 295         </listitem>
 296       </varlistentry>
 297
 298       <varlistentry>
 299         <term>-u <replaceable class="parameter">user</replaceable></term>
 300         <listitem>
 301           <para>Setuid
 302             to <replaceable class="parameter">user</replaceable> after completing
 303             privileged operations, such as creating sockets that
 304             listen on privileged ports.
 305           </para>
 306         </listitem>
 307       </varlistentry>
 308
 309       <varlistentry>
 310         <term>-v</term>
 311         <listitem>
 312           <para>
 313             Report the version number and exit.
 314           </para>
 315         </listitem>
 316       </varlistentry>
 317
 318     </variablelist>
 319
 320   </refsect1>
 321
 322   <refsect1>
 323     <title>FILES</title>
 324
 325     <variablelist>
 326
 327       <varlistentry>
 328         <term><filename>/etc/resolv.conf</filename></term>
 329         <listitem>
 330           <para>
 331             The default configuration file.
 332           </para>
 333         </listitem>
 334       </varlistentry>
 335
 336       <varlistentry>
 337         <term><filename>/var/run/lwresd.pid</filename></term>
 338         <listitem>
 339           <para>
 340             The default process-id file.
 341           </para>
 342         </listitem>
 343       </varlistentry>
 344
 345     </variablelist>
 346
 347   </refsect1>
 348
 349   <refsect1>
 350     <title>SEE ALSO</title>
 351     <para><citerefentry>
 352         <refentrytitle>named</refentrytitle><manvolnum>8</manvolnum>
 353       </citerefentry>,
 354       <citerefentry>
 355         <refentrytitle>lwres</refentrytitle><manvolnum>3</manvolnum>
 356       </citerefentry>,
 357       <citerefentry>
 358         <refentrytitle>resolver</refentrytitle><manvolnum>5</manvolnum>
 359       </citerefentry>.
 360     </para>
 361   </refsect1>
 362
 363   <refsect1>
 364     <title>AUTHOR</title>
 365     <para><corpauthor>Internet Systems Consortium</corpauthor>
 366     </para>
 367   </refsect1>
 368
 369 </refentry><!--
 370  - Local variables:
 371  - mode: sgml
 372  - End:
 373 -->