1<!-- 2 - Copyright (C) 2004-2015 Internet Systems Consortium, Inc. ("ISC") 3 - Copyright (C) 2000-2003 Internet Software Consortium. 4 - 5 - Permission to use, copy, modify, and/or distribute this software for any 6 - purpose with or without fee is hereby granted, provided that the above 7 - copyright notice and this permission notice appear in all copies. 8 - 9 - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH 10 - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY 11 - AND FITNESS. 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For more 57 information on the DNS, see RFCs 1033, 1034, and 1035. 58 </p> 59<p> 60 When invoked without arguments, <span><strong class="command">named</strong></span> 61 will 62 read the default configuration file 63 <code class="filename">/etc/named.conf</code>, read any initial 64 data, and listen for queries. 65 </p> 66</div> 67<div class="refsect1" lang="en"> 68<a name="id2646803"></a><h2>OPTIONS</h2> 69<div class="variablelist"><dl> 70<dt><span class="term">-4</span></dt> 71<dd><p> 72 Use IPv4 only even if the host machine is capable of IPv6. 73 <code class="option">-4</code> and <code class="option">-6</code> are mutually 74 exclusive. 75 </p></dd> 76<dt><span class="term">-6</span></dt> 77<dd><p> 78 Use IPv6 only even if the host machine is capable of IPv4. 79 <code class="option">-4</code> and <code class="option">-6</code> are mutually 80 exclusive. 81 </p></dd> 82<dt><span class="term">-c <em class="replaceable"><code>config-file</code></em></span></dt> 83<dd><p> 84 Use <em class="replaceable"><code>config-file</code></em> as the 85 configuration file instead of the default, 86 <code class="filename">/etc/named.conf</code>. To 87 ensure that reloading the configuration file continues 88 to work after the server has changed its working 89 directory due to to a possible 90 <code class="option">directory</code> option in the configuration 91 file, <em class="replaceable"><code>config-file</code></em> should be 92 an absolute pathname. 93 </p></dd> 94<dt><span class="term">-d <em class="replaceable"><code>debug-level</code></em></span></dt> 95<dd><p> 96 Set the daemon's debug level to <em class="replaceable"><code>debug-level</code></em>. 97 Debugging traces from <span><strong class="command">named</strong></span> become 98 more verbose as the debug level increases. 99 </p></dd> 100<dt><span class="term">-D <em class="replaceable"><code>string</code></em></span></dt> 101<dd><p> 102 Specifies a string that is used to identify a instance of 103 <span><strong class="command">named</strong></span> in a process listing. The contents 104 of <em class="replaceable"><code>string</code></em> are 105 not examined. 106 </p></dd> 107<dt><span class="term">-E <em class="replaceable"><code>engine-name</code></em></span></dt> 108<dd> 109<p> 110 When applicable, specifies the hardware to use for 111 cryptographic operations, such as a secure key store used 112 for signing. 113 </p> 114<p> 115 When BIND is built with OpenSSL PKCS#11 support, this defaults 116 to the string "pkcs11", which identifies an OpenSSL engine 117 that can drive a cryptographic accelerator or hardware service 118 module. When BIND is built with native PKCS#11 cryptography 119 (--enable-native-pkcs11), it defaults to the path of the PKCS#11 120 provider library specified via "--with-pkcs11". 121 </p> 122</dd> 123<dt><span class="term">-f</span></dt> 124<dd><p> 125 Run the server in the foreground (i.e. do not daemonize). 126 </p></dd> 127<dt><span class="term">-g</span></dt> 128<dd><p> 129 Run the server in the foreground and force all logging 130 to <code class="filename">stderr</code>. 131 </p></dd> 132<dt><span class="term">-m <em class="replaceable"><code>flag</code></em></span></dt> 133<dd><p> 134 Turn on memory usage debugging flags. Possible flags are 135 <em class="replaceable"><code>usage</code></em>, 136 <em class="replaceable"><code>trace</code></em>, 137 <em class="replaceable"><code>record</code></em>, 138 <em class="replaceable"><code>size</code></em>, and 139 <em class="replaceable"><code>mctx</code></em>. 140 These correspond to the ISC_MEM_DEBUGXXXX flags described in 141 <code class="filename"><isc/mem.h></code>. 142 </p></dd> 143<dt><span class="term">-n <em class="replaceable"><code>#cpus</code></em></span></dt> 144<dd><p> 145 Create <em class="replaceable"><code>#cpus</code></em> worker threads 146 to take advantage of multiple CPUs. If not specified, 147 <span><strong class="command">named</strong></span> will try to determine the 148 number of CPUs present and create one thread per CPU. 149 If it is unable to determine the number of CPUs, a 150 single worker thread will be created. 151 </p></dd> 152<dt><span class="term">-p <em class="replaceable"><code>port</code></em></span></dt> 153<dd><p> 154 Listen for queries on port <em class="replaceable"><code>port</code></em>. If not 155 specified, the default is port 53. 156 </p></dd> 157<dt><span class="term">-s</span></dt> 158<dd> 159<p> 160 Write memory usage statistics to <code class="filename">stdout</code> on exit. 161 </p> 162<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> 163<h3 class="title">Note</h3> 164<p> 165 This option is mainly of interest to BIND 9 developers 166 and may be removed or changed in a future release. 167 </p> 168</div> 169</dd> 170<dt><span class="term">-S <em class="replaceable"><code>#max-socks</code></em></span></dt> 171<dd> 172<p> 173 Allow <span><strong class="command">named</strong></span> to use up to 174 <em class="replaceable"><code>#max-socks</code></em> sockets. 175 The default value is 4096 on systems built with default 176 configuration options, and 21000 on systems built with 177 "configure --with-tuning=large". 178 </p> 179<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"> 180<h3 class="title">Warning</h3> 181<p> 182 This option should be unnecessary for the vast majority 183 of users. 184 The use of this option could even be harmful because the 185 specified value may exceed the limitation of the 186 underlying system API. 187 It is therefore set only when the default configuration 188 causes exhaustion of file descriptors and the 189 operational environment is known to support the 190 specified number of sockets. 191 Note also that the actual maximum number is normally a little 192 fewer than the specified value because 193 <span><strong class="command">named</strong></span> reserves some file descriptors 194 for its internal use. 195 </p> 196</div> 197</dd> 198<dt><span class="term">-t <em class="replaceable"><code>directory</code></em></span></dt> 199<dd> 200<p>Chroot 201 to <em class="replaceable"><code>directory</code></em> after 202 processing the command line arguments, but before 203 reading the configuration file. 204 </p> 205<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"> 206<h3 class="title">Warning</h3> 207<p> 208 This option should be used in conjunction with the 209 <code class="option">-u</code> option, as chrooting a process 210 running as root doesn't enhance security on most 211 systems; the way <code class="function">chroot(2)</code> is 212 defined allows a process with root privileges to 213 escape a chroot jail. 214 </p> 215</div> 216</dd> 217<dt><span class="term">-U <em class="replaceable"><code>#listeners</code></em></span></dt> 218<dd><p> 219 Use <em class="replaceable"><code>#listeners</code></em> 220 worker threads to listen for incoming UDP packets on each 221 address. If not specified, <span><strong class="command">named</strong></span> will 222 calculate a default value based on the number of detected 223 CPUs: 1 for 1 CPU, 2 for 2-4 CPUs, and the number of 224 detected CPUs divided by 2 for values higher than 4. 225 If <code class="option">-n</code> has been set to a higher value than 226 the number of detected CPUs, then <code class="option">-U</code> may 227 be increased as high as that value, but no higher. 228 </p></dd> 229<dt><span class="term">-u <em class="replaceable"><code>user</code></em></span></dt> 230<dd> 231<p>Setuid 232 to <em class="replaceable"><code>user</code></em> after completing 233 privileged operations, such as creating sockets that 234 listen on privileged ports. 235 </p> 236<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> 237<h3 class="title">Note</h3> 238<p> 239 On Linux, <span><strong class="command">named</strong></span> uses the kernel's 240 capability mechanism to drop all root privileges 241 except the ability to <code class="function">bind(2)</code> to 242 a 243 privileged port and set process resource limits. 244 Unfortunately, this means that the <code class="option">-u</code> 245 option only works when <span><strong class="command">named</strong></span> is 246 run 247 on kernel 2.2.18 or later, or kernel 2.3.99-pre3 or 248 later, since previous kernels did not allow privileges 249 to be retained after <code class="function">setuid(2)</code>. 250 </p> 251</div> 252</dd> 253<dt><span class="term">-v</span></dt> 254<dd><p> 255 Report the version number and exit. 256 </p></dd> 257<dt><span class="term">-V</span></dt> 258<dd><p> 259 Report the version number and build options, and exit. 260 </p></dd> 261<dt><span class="term">-x <em class="replaceable"><code>cache-file</code></em></span></dt> 262<dd> 263<p> 264 Load data from <em class="replaceable"><code>cache-file</code></em> into the 265 cache of the default view. 266 </p> 267<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"> 268<h3 class="title">Warning</h3> 269<p> 270 This option must not be used. It is only of interest 271 to BIND 9 developers and may be removed or changed in a 272 future release. 273 </p> 274</div> 275</dd> 276</dl></div> 277</div> 278<div class="refsect1" lang="en"> 279<a name="id2679367"></a><h2>SIGNALS</h2> 280<p> 281 In routine operation, signals should not be used to control 282 the nameserver; <span><strong class="command">rndc</strong></span> should be used 283 instead. 284 </p> 285<div class="variablelist"><dl> 286<dt><span class="term">SIGHUP</span></dt> 287<dd><p> 288 Force a reload of the server. 289 </p></dd> 290<dt><span class="term">SIGINT, SIGTERM</span></dt> 291<dd><p> 292 Shut down the server. 293 </p></dd> 294</dl></div> 295<p> 296 The result of sending any other signals to the server is undefined. 297 </p> 298</div> 299<div class="refsect1" lang="en"> 300<a name="id2679417"></a><h2>CONFIGURATION</h2> 301<p> 302 The <span><strong class="command">named</strong></span> configuration file is too complex 303 to describe in detail here. A complete description is provided 304 in the 305 <em class="citetitle">BIND 9 Administrator Reference Manual</em>. 306 </p> 307<p> 308 <span><strong class="command">named</strong></span> inherits the <code class="function">umask</code> 309 (file creation mode mask) from the parent process. If files 310 created by <span><strong class="command">named</strong></span>, such as journal files, 311 need to have custom permissions, the <code class="function">umask</code> 312 should be set explicitly in the script used to start the 313 <span><strong class="command">named</strong></span> process. 314 </p> 315</div> 316<div class="refsect1" lang="en"> 317<a name="id2679466"></a><h2>FILES</h2> 318<div class="variablelist"><dl> 319<dt><span class="term"><code class="filename">/etc/named.conf</code></span></dt> 320<dd><p> 321 The default configuration file. 322 </p></dd> 323<dt><span class="term"><code class="filename">/var/run/named/named.pid</code></span></dt> 324<dd><p> 325 The default process-id file. 326 </p></dd> 327</dl></div> 328</div> 329<div class="refsect1" lang="en"> 330<a name="id2679510"></a><h2>SEE ALSO</h2> 331<p><em class="citetitle">RFC 1033</em>, 332 <em class="citetitle">RFC 1034</em>, 333 <em class="citetitle">RFC 1035</em>, 334 <span class="citerefentry"><span class="refentrytitle">named-checkconf</span>(8)</span>, 335 <span class="citerefentry"><span class="refentrytitle">named-checkzone</span>(8)</span>, 336 <span class="citerefentry"><span class="refentrytitle">rndc</span>(8)</span>, 337 <span class="citerefentry"><span class="refentrytitle">lwresd</span>(8)</span>, 338 <span class="citerefentry"><span class="refentrytitle">named.conf</span>(5)</span>, 339 <em class="citetitle">BIND 9 Administrator Reference Manual</em>. 340 </p> 341</div> 342<div class="refsect1" lang="en"> 343<a name="id2679580"></a><h2>AUTHOR</h2> 344<p><span class="corpauthor">Internet Systems Consortium</span> 345 </p> 346</div> 347</div> 348<div class="navfooter"> 349<hr> 350<table width="100%" summary="Navigation footer"> 351<tr> 352<td width="40%" align="left"> 353<a accesskey="p" href="man.named-checkzone.html">Prev</a>�</td> 354<td width="20%" align="center"><a accesskey="u" href="Bv9ARM.ch13.html">Up</a></td> 355<td width="40%" align="right">�<a accesskey="n" href="man.named-journalprint.html">Next</a> 356</td> 357</tr> 358<tr> 359<td width="40%" align="left" valign="top"> 360<span class="application">named-checkzone</span>�</td> 361<td width="20%" align="center"><a accesskey="h" href="Bv9ARM.html">Home</a></td> 362<td width="40%" align="right" valign="top">�<span class="application">named-journalprint</span> 363</td> 364</tr> 365</table> 366</div> 367<p style="text-align: center;">BIND 9.10.2-P4</p> 368</body> 369</html> 370