man.named.html revision 262706
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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="id2641442"></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">-E <em class="replaceable"><code>engine-name</code></em></span></dt> 101<dd><p> 102 Use a crypto hardware (OpenSSL engine) for the crypto operations 103 it supports, for instance re-signing with private keys from 104 a secure key store. When compiled with PKCS#11 support 105 <em class="replaceable"><code>engine-name</code></em> 106 defaults to pkcs11, the empty name resets it to no engine. 107 </p></dd> 108<dt><span class="term">-f</span></dt> 109<dd><p> 110 Run the server in the foreground (i.e. do not daemonize). 111 </p></dd> 112<dt><span class="term">-g</span></dt> 113<dd><p> 114 Run the server in the foreground and force all logging 115 to <code class="filename">stderr</code>. 116 </p></dd> 117<dt><span class="term">-m <em class="replaceable"><code>flag</code></em></span></dt> 118<dd><p> 119 Turn on memory usage debugging flags. Possible flags are 120 <em class="replaceable"><code>usage</code></em>, 121 <em class="replaceable"><code>trace</code></em>, 122 <em class="replaceable"><code>record</code></em>, 123 <em class="replaceable"><code>size</code></em>, and 124 <em class="replaceable"><code>mctx</code></em>. 125 These correspond to the ISC_MEM_DEBUGXXXX flags described in 126 <code class="filename"><isc/mem.h></code>. 127 </p></dd> 128<dt><span class="term">-n <em class="replaceable"><code>#cpus</code></em></span></dt> 129<dd><p> 130 Create <em class="replaceable"><code>#cpus</code></em> worker threads 131 to take advantage of multiple CPUs. If not specified, 132 <span><strong class="command">named</strong></span> will try to determine the 133 number of CPUs present and create one thread per CPU. 134 If it is unable to determine the number of CPUs, a 135 single worker thread will be created. 136 </p></dd> 137<dt><span class="term">-p <em class="replaceable"><code>port</code></em></span></dt> 138<dd><p> 139 Listen for queries on port <em class="replaceable"><code>port</code></em>. If not 140 specified, the default is port 53. 141 </p></dd> 142<dt><span class="term">-s</span></dt> 143<dd> 144<p> 145 Write memory usage statistics to <code class="filename">stdout</code> on exit. 146 </p> 147<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> 148<h3 class="title">Note</h3> 149<p> 150 This option is mainly of interest to BIND 9 developers 151 and may be removed or changed in a future release. 152 </p> 153</div> 154</dd> 155<dt><span class="term">-S <em class="replaceable"><code>#max-socks</code></em></span></dt> 156<dd> 157<p> 158 Allow <span><strong class="command">named</strong></span> to use up to 159 <em class="replaceable"><code>#max-socks</code></em> sockets. 160 </p> 161<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"> 162<h3 class="title">Warning</h3> 163<p> 164 This option should be unnecessary for the vast majority 165 of users. 166 The use of this option could even be harmful because the 167 specified value may exceed the limitation of the 168 underlying system API. 169 It is therefore set only when the default configuration 170 causes exhaustion of file descriptors and the 171 operational environment is known to support the 172 specified number of sockets. 173 Note also that the actual maximum number is normally a little 174 fewer than the specified value because 175 <span><strong class="command">named</strong></span> reserves some file descriptors 176 for its internal use. 177 </p> 178</div> 179</dd> 180<dt><span class="term">-t <em class="replaceable"><code>directory</code></em></span></dt> 181<dd> 182<p>Chroot 183 to <em class="replaceable"><code>directory</code></em> after 184 processing the command line arguments, but before 185 reading the configuration file. 186 </p> 187<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"> 188<h3 class="title">Warning</h3> 189<p> 190 This option should be used in conjunction with the 191 <code class="option">-u</code> option, as chrooting a process 192 running as root doesn't enhance security on most 193 systems; the way <code class="function">chroot(2)</code> is 194 defined allows a process with root privileges to 195 escape a chroot jail. 196 </p> 197</div> 198</dd> 199<dt><span class="term">-U <em class="replaceable"><code>#listeners</code></em></span></dt> 200<dd><p> 201 Use <em class="replaceable"><code>#listeners</code></em> 202 worker threads to listen for incoming UDP packets on each 203 address. If not specified, <span><strong class="command">named</strong></span> will 204 use the number of detected CPUs. If <code class="option">-n</code> 205 has been set to a higher value than the number of CPUs, 206 then <code class="option">-U</code> may be increased as high as that 207 value, but no higher. 208 </p></dd> 209<dt><span class="term">-u <em class="replaceable"><code>user</code></em></span></dt> 210<dd> 211<p>Setuid 212 to <em class="replaceable"><code>user</code></em> after completing 213 privileged operations, such as creating sockets that 214 listen on privileged ports. 215 </p> 216<div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> 217<h3 class="title">Note</h3> 218<p> 219 On Linux, <span><strong class="command">named</strong></span> uses the kernel's 220 capability mechanism to drop all root privileges 221 except the ability to <code class="function">bind(2)</code> to 222 a 223 privileged port and set process resource limits. 224 Unfortunately, this means that the <code class="option">-u</code> 225 option only works when <span><strong class="command">named</strong></span> is 226 run 227 on kernel 2.2.18 or later, or kernel 2.3.99-pre3 or 228 later, since previous kernels did not allow privileges 229 to be retained after <code class="function">setuid(2)</code>. 230 </p> 231</div> 232</dd> 233<dt><span class="term">-v</span></dt> 234<dd><p> 235 Report the version number and exit. 236 </p></dd> 237<dt><span class="term">-V</span></dt> 238<dd><p> 239 Report the version number and build options, and exit. 240 </p></dd> 241<dt><span class="term">-x <em class="replaceable"><code>cache-file</code></em></span></dt> 242<dd> 243<p> 244 Load data from <em class="replaceable"><code>cache-file</code></em> into the 245 cache of the default view. 246 </p> 247<div class="warning" style="margin-left: 0.5in; margin-right: 0.5in;"> 248<h3 class="title">Warning</h3> 249<p> 250 This option must not be used. It is only of interest 251 to BIND 9 developers and may be removed or changed in a 252 future release. 253 </p> 254</div> 255</dd> 256</dl></div> 257</div> 258<div class="refsect1" lang="en"> 259<a name="id2666470"></a><h2>SIGNALS</h2> 260<p> 261 In routine operation, signals should not be used to control 262 the nameserver; <span><strong class="command">rndc</strong></span> should be used 263 instead. 264 </p> 265<div class="variablelist"><dl> 266<dt><span class="term">SIGHUP</span></dt> 267<dd><p> 268 Force a reload of the server. 269 </p></dd> 270<dt><span class="term">SIGINT, SIGTERM</span></dt> 271<dd><p> 272 Shut down the server. 273 </p></dd> 274</dl></div> 275<p> 276 The result of sending any other signals to the server is undefined. 277 </p> 278</div> 279<div class="refsect1" lang="en"> 280<a name="id2673074"></a><h2>CONFIGURATION</h2> 281<p> 282 The <span><strong class="command">named</strong></span> configuration file is too complex 283 to describe in detail here. A complete description is provided 284 in the 285 <em class="citetitle">BIND 9 Administrator Reference Manual</em>. 286 </p> 287<p> 288 <span><strong class="command">named</strong></span> inherits the <code class="function">umask</code> 289 (file creation mode mask) from the parent process. If files 290 created by <span><strong class="command">named</strong></span>, such as journal files, 291 need to have custom permissions, the <code class="function">umask</code> 292 should be set explicitly in the script used to start the 293 <span><strong class="command">named</strong></span> process. 294 </p> 295</div> 296<div class="refsect1" lang="en"> 297<a name="id2673123"></a><h2>FILES</h2> 298<div class="variablelist"><dl> 299<dt><span class="term"><code class="filename">/etc/named.conf</code></span></dt> 300<dd><p> 301 The default configuration file. 302 </p></dd> 303<dt><span class="term"><code class="filename">/var/run/named/named.pid</code></span></dt> 304<dd><p> 305 The default process-id file. 306 </p></dd> 307</dl></div> 308</div> 309<div class="refsect1" lang="en"> 310<a name="id2673166"></a><h2>SEE ALSO</h2> 311<p><em class="citetitle">RFC 1033</em>, 312 <em class="citetitle">RFC 1034</em>, 313 <em class="citetitle">RFC 1035</em>, 314 <span class="citerefentry"><span class="refentrytitle">named-checkconf</span>(8)</span>, 315 <span class="citerefentry"><span class="refentrytitle">named-checkzone</span>(8)</span>, 316 <span class="citerefentry"><span class="refentrytitle">rndc</span>(8)</span>, 317 <span class="citerefentry"><span class="refentrytitle">lwresd</span>(8)</span>, 318 <span class="citerefentry"><span class="refentrytitle">named.conf</span>(5)</span>, 319 <em class="citetitle">BIND 9 Administrator Reference Manual</em>. 320 </p> 321</div> 322<div class="refsect1" lang="en"> 323<a name="id2673237"></a><h2>AUTHOR</h2> 324<p><span class="corpauthor">Internet Systems Consortium</span> 325 </p> 326</div> 327</div> 328<div class="navfooter"> 329<hr> 330<table width="100%" summary="Navigation footer"> 331<tr> 332<td width="40%" align="left"> 333<a accesskey="p" href="man.named-checkzone.html">Prev</a>�</td> 334<td width="20%" align="center"><a accesskey="u" href="Bv9ARM.ch10.html">Up</a></td> 335<td width="40%" align="right">�<a accesskey="n" href="man.named-journalprint.html">Next</a> 336</td> 337</tr> 338<tr> 339<td width="40%" align="left" valign="top"> 340<span class="application">named-checkzone</span>�</td> 341<td width="20%" align="center"><a accesskey="h" href="Bv9ARM.html">Home</a></td> 342<td width="40%" align="right" valign="top">�<span class="application">named-journalprint</span> 343</td> 344</tr> 345</table> 346</div> 347</body> 348</html> 349