1<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> 2<html> 3<!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ --> 4<head> 5<meta http-equiv="Content-Type" content="text/html; charset=utf-8"> 6<title>ntpd: Network Time Protocol (NTP) Daemon User’s Manual</title> 7 8<meta name="description" content="ntpd: Network Time Protocol (NTP) Daemon User’s Manual"> 9<meta name="keywords" content="ntpd: Network Time Protocol (NTP) Daemon User’s Manual"> 10<meta name="resource-type" content="document"> 11<meta name="distribution" content="global"> 12<meta name="Generator" content="makeinfo"> 13<link href="#Top" rel="start" title="Top"> 14<link href="dir.html#Top" rel="up" title="(dir)"> 15<style type="text/css"> 16<!-- 17a.summary-letter {text-decoration: none} 18blockquote.indentedblock {margin-right: 0em} 19blockquote.smallindentedblock {margin-right: 0em; font-size: smaller} 20blockquote.smallquotation {font-size: smaller} 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class="header"> 55<p> 56Next: <a href="#ntpd-Description" accesskey="n" rel="next">ntpd Description</a>, Previous: <a href="dir.html#Top" accesskey="p" rel="prev">(dir)</a>, Up: <a href="dir.html#Top" accesskey="u" rel="up">(dir)</a> </p> 57</div> 58<a name="ntpd_003a-Network-Time-Protocol-_0028NTP_0029-Daemon-User-Manual"></a> 59<h1 class="top">ntpd: Network Time Protocol (NTP) Daemon User Manual</h1> 60 61<p>The <code>ntpd</code> program is an operating system daemon that synchronizes the 62system clock to remote NTP time servers or local reference clocks. 63It is a complete implementation of NTP version 4 defined by RFC-5905, but 64also retains compatible with version 3 defined by RFC-1305 and versions 651 and 2, defined by RFC-1059 and RFC-1119, respectively. 66The program can operate in any of several modes, including client/server, 67symmetric and broadcast modes, and with both symmetric-key and public-key 68cryptography. 69</p> 70<p>This document applies to version 4.2.8p15 of <code>ntpd</code>. 71</p> 72<a name="SEC_Overview"></a> 73<h2 class="shortcontents-heading">Short Table of Contents</h2> 74 75<div class="shortcontents"> 76<ul class="no-bullet"> 77<li><a name="stoc-Description" href="#toc-Description">1 Description</a></li> 78</ul> 79</div> 80 81 82<table class="menu" border="0" cellspacing="0"> 83<tr><td align="left" valign="top">• <a href="#ntpd-Description" accesskey="1">ntpd Description</a>:</td><td> </td><td align="left" valign="top">Description 84</td></tr> 85<tr><td align="left" valign="top">• <a href="#ntpd-Invocation" accesskey="2">ntpd Invocation</a>:</td><td> </td><td align="left" valign="top">Invoking ntpd 86</td></tr> 87<tr><td align="left" valign="top">• <a href="#Usage" accesskey="3">Usage</a>:</td><td> </td><td align="left" valign="top">Usage 88</td></tr> 89</table> 90 91<hr> 92<a name="ntpd-Description"></a> 93<div class="header"> 94<p> 95Next: <a href="#ntpd-Invocation" accesskey="n" rel="next">ntpd Invocation</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> </p> 96</div> 97<a name="Description"></a> 98<h2 class="chapter">1 Description</h2> 99 100<p>The <code>ntpd</code> program ordinarily requires 101a configuration file described at ‘ntp.conf’. 102This configuration file contains configuration commands described on 103the pages listed above. 104However a client can discover remote servers and configure them 105automatically. 106This makes it possible to deploy a fleet of workstations without 107specifying configuration details specific to the local environment. 108</p> 109<p>The <code>ntpd</code> program normally operates continuously while adjusting the 110system time and frequency, but in some cases this might not be 111practical. 112With the <code>-q</code> option <code>ntpd</code> operates as in continuous mode, but 113exits just after setting the clock for the first time. 114Most applications will probably want to specify the <code>iburst</code> 115option with the <code>server</code> command. 116With this option an initial volley of messages is exchanged to 117groom the data and set the clock in about ten seconds’ time. 118If nothing is heard after a few minutes’ time, 119the daemon times out and exits without setting the clock. 120</p> 121<table class="menu" border="0" cellspacing="0"> 122<tr><td align="left" valign="top">• <a href="#ntpd-Invocation" accesskey="1">ntpd Invocation</a>:</td><td> </td><td align="left" valign="top"> 123</td></tr> 124<tr><td align="left" valign="top">• <a href="#Usage" accesskey="2">Usage</a>:</td><td> </td><td align="left" valign="top"> 125</td></tr> 126</table> 127 128<hr> 129<a name="ntpd-Invocation"></a> 130<div class="header"> 131<p> 132Next: <a href="#Usage" accesskey="n" rel="next">Usage</a>, Previous: <a href="#ntpd-Description" accesskey="p" rel="prev">ntpd Description</a>, Up: <a href="#ntpd-Description" accesskey="u" rel="up">ntpd Description</a> </p> 133</div> 134<a name="Invoking-ntpd"></a> 135<h3 class="section">1.1 Invoking ntpd</h3> 136<a name="index-ntpd"></a> 137<a name="index-NTP-daemon-program"></a> 138 139 140 141<p>The 142<code>ntpd</code> 143utility is an operating system daemon which sets 144and maintains the system time of day in synchronism with Internet 145standard time servers. 146It is a complete implementation of the 147Network Time Protocol (NTP) version 4, as defined by RFC-5905, 148but also retains compatibility with 149version 3, as defined by RFC-1305, and versions 1 150and 2, as defined by RFC-1059 and RFC-1119, respectively. 151</p> 152<p>The 153<code>ntpd</code> 154utility does most computations in 64-bit floating point 155arithmetic and does relatively clumsy 64-bit fixed point operations 156only when necessary to preserve the ultimate precision, about 232 157picoseconds. 158While the ultimate precision is not achievable with 159ordinary workstations and networks of today, it may be required 160with future gigahertz CPU clocks and gigabit LANs. 161</p> 162<p>Ordinarily, 163<code>ntpd</code> 164reads the 165<code>ntp.conf(5)</code> 166configuration file at startup time in order to determine the 167synchronization sources and operating modes. 168It is also possible to 169specify a working, although limited, configuration entirely on the 170command line, obviating the need for a configuration file. 171This may 172be particularly useful when the local host is to be configured as a 173broadcast/multicast client, with all peers being determined by 174listening to broadcasts at run time. 175</p> 176<p>If NetInfo support is built into 177<code>ntpd</code> 178then 179<code>ntpd</code> 180will attempt to read its configuration from the 181NetInfo if the default 182<code>ntp.conf(5)</code> 183file cannot be read and no file is 184specified by the 185<code>-c</code> 186option. 187</p> 188<p>Various internal 189<code>ntpd</code> 190variables can be displayed and 191configuration options altered while the 192<code>ntpd</code> 193is running 194using the 195<code>ntpq(1ntpqmdoc)</code> 196and 197<code>ntpdc(1ntpdcmdoc)</code> 198utility programs. 199</p> 200<p>When 201<code>ntpd</code> 202starts it looks at the value of 203<code>umask(2)</code>, 204and if zero 205<code>ntpd</code> 206will set the 207<code>umask(2)</code> 208to 022. 209</p> 210<p>This section was generated by <strong>AutoGen</strong>, 211using the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntpd</code> program. 212This software is released under the NTP license, <http://ntp.org/license>. 213</p> 214<table class="menu" border="0" cellspacing="0"> 215<tr><td align="left" valign="top">• <a href="#ntpd-usage" accesskey="1">ntpd usage</a>:</td><td> </td><td align="left" valign="top">ntpd help/usage (<samp>--help</samp>) 216</td></tr> 217<tr><td align="left" valign="top">• <a href="#ntpd-ipv4" accesskey="2">ntpd ipv4</a>:</td><td> </td><td align="left" valign="top">ipv4 option (-4) 218</td></tr> 219<tr><td align="left" valign="top">• <a href="#ntpd-ipv6" accesskey="3">ntpd ipv6</a>:</td><td> </td><td align="left" valign="top">ipv6 option (-6) 220</td></tr> 221<tr><td align="left" valign="top">• <a href="#ntpd-authreq" accesskey="4">ntpd authreq</a>:</td><td> </td><td align="left" valign="top">authreq option (-a) 222</td></tr> 223<tr><td align="left" valign="top">• <a href="#ntpd-authnoreq" accesskey="5">ntpd authnoreq</a>:</td><td> </td><td align="left" valign="top">authnoreq option (-A) 224</td></tr> 225<tr><td align="left" valign="top">• <a href="#ntpd-configfile" accesskey="6">ntpd configfile</a>:</td><td> </td><td align="left" valign="top">configfile option (-c) 226</td></tr> 227<tr><td align="left" valign="top">• <a href="#ntpd-driftfile" accesskey="7">ntpd driftfile</a>:</td><td> </td><td align="left" valign="top">driftfile option (-f) 228</td></tr> 229<tr><td align="left" valign="top">• <a href="#ntpd-panicgate" accesskey="8">ntpd panicgate</a>:</td><td> </td><td align="left" valign="top">panicgate option (-g) 230</td></tr> 231<tr><td align="left" valign="top">• <a href="#ntpd-force_002dstep_002donce" accesskey="9">ntpd force-step-once</a>:</td><td> </td><td align="left" valign="top">force-step-once option (-G) 232</td></tr> 233<tr><td align="left" valign="top">• <a href="#ntpd-jaildir">ntpd jaildir</a>:</td><td> </td><td align="left" valign="top">jaildir option (-i) 234</td></tr> 235<tr><td align="left" valign="top">• <a href="#ntpd-interface">ntpd interface</a>:</td><td> </td><td align="left" valign="top">interface option (-I) 236</td></tr> 237<tr><td align="left" valign="top">• <a href="#ntpd-keyfile">ntpd keyfile</a>:</td><td> </td><td align="left" valign="top">keyfile option (-k) 238</td></tr> 239<tr><td align="left" valign="top">• <a href="#ntpd-logfile">ntpd logfile</a>:</td><td> </td><td align="left" valign="top">logfile option (-l) 240</td></tr> 241<tr><td align="left" valign="top">• <a href="#ntpd-novirtualips">ntpd novirtualips</a>:</td><td> </td><td align="left" valign="top">novirtualips option (-L) 242</td></tr> 243<tr><td align="left" valign="top">• <a href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>:</td><td> </td><td align="left" valign="top">modifymmtimer option (-M) 244</td></tr> 245<tr><td align="left" valign="top">• <a href="#ntpd-nice">ntpd nice</a>:</td><td> </td><td align="left" valign="top">nice option (-N) 246</td></tr> 247<tr><td align="left" valign="top">• <a href="#ntpd-pidfile">ntpd pidfile</a>:</td><td> </td><td align="left" valign="top">pidfile option (-p) 248</td></tr> 249<tr><td align="left" valign="top">• <a href="#ntpd-priority">ntpd priority</a>:</td><td> </td><td align="left" valign="top">priority option (-P) 250</td></tr> 251<tr><td align="left" valign="top">• <a href="#ntpd-quit">ntpd quit</a>:</td><td> </td><td align="left" valign="top">quit option (-q) 252</td></tr> 253<tr><td align="left" valign="top">• <a href="#ntpd-propagationdelay">ntpd propagationdelay</a>:</td><td> </td><td align="left" valign="top">propagationdelay option (-r) 254</td></tr> 255<tr><td align="left" valign="top">• <a href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>:</td><td> </td><td align="left" valign="top">saveconfigquit option 256</td></tr> 257<tr><td align="left" valign="top">• <a href="#ntpd-statsdir">ntpd statsdir</a>:</td><td> </td><td align="left" valign="top">statsdir option (-s) 258</td></tr> 259<tr><td align="left" valign="top">• <a href="#ntpd-trustedkey">ntpd trustedkey</a>:</td><td> </td><td align="left" valign="top">trustedkey option (-t) 260</td></tr> 261<tr><td align="left" valign="top">• <a href="#ntpd-user">ntpd user</a>:</td><td> </td><td align="left" valign="top">user option (-u) 262</td></tr> 263<tr><td align="left" valign="top">• <a href="#ntpd-updateinterval">ntpd updateinterval</a>:</td><td> </td><td align="left" valign="top">updateinterval option (-U) 264</td></tr> 265<tr><td align="left" valign="top">• <a href="#ntpd-wait_002dsync">ntpd wait-sync</a>:</td><td> </td><td align="left" valign="top">wait-sync option (-w) 266</td></tr> 267<tr><td align="left" valign="top">• <a href="#ntpd-slew">ntpd slew</a>:</td><td> </td><td align="left" valign="top">slew option (-x) 268</td></tr> 269<tr><td align="left" valign="top">• <a href="#ntpd-usepcc">ntpd usepcc</a>:</td><td> </td><td align="left" valign="top">usepcc option 270</td></tr> 271<tr><td align="left" valign="top">• <a href="#ntpd-pccfreq">ntpd pccfreq</a>:</td><td> </td><td align="left" valign="top">pccfreq option 272</td></tr> 273<tr><td align="left" valign="top">• <a href="#ntpd-mdns">ntpd mdns</a>:</td><td> </td><td align="left" valign="top">mdns option (-m) 274</td></tr> 275<tr><td align="left" valign="top">• <a href="#ntpd-config">ntpd config</a>:</td><td> </td><td align="left" valign="top">presetting/configuring ntpd 276</td></tr> 277<tr><td align="left" valign="top">• <a href="#ntpd-exit-status">ntpd exit status</a>:</td><td> </td><td align="left" valign="top">exit status 278</td></tr> 279<tr><td align="left" valign="top">• <a href="#ntpd-Usage">ntpd Usage</a>:</td><td> </td><td align="left" valign="top">Usage 280</td></tr> 281<tr><td align="left" valign="top">• <a href="#ntpd-Files">ntpd Files</a>:</td><td> </td><td align="left" valign="top">Files 282</td></tr> 283<tr><td align="left" valign="top">• <a href="#ntpd-See-Also">ntpd See Also</a>:</td><td> </td><td align="left" valign="top">See Also 284</td></tr> 285<tr><td align="left" valign="top">• <a href="#ntpd-Bugs">ntpd Bugs</a>:</td><td> </td><td align="left" valign="top">Bugs 286</td></tr> 287<tr><td align="left" valign="top">• <a href="#ntpd-Notes">ntpd Notes</a>:</td><td> </td><td align="left" valign="top">Notes 288</td></tr> 289</table> 290 291<hr> 292<a name="ntpd-usage"></a> 293<div class="header"> 294<p> 295Next: <a href="#ntpd-ipv4" accesskey="n" rel="next">ntpd ipv4</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 296</div> 297<a name="ntpd-help_002fusage-_0028_002d_002dhelp_0029"></a> 298<h4 class="subsection">1.1.1 ntpd help/usage (<samp>--help</samp>)</h4> 299<a name="index-ntpd-help"></a> 300 301<p>This is the automatically generated usage text for ntpd. 302</p> 303<p>The text printed is the same whether selected with the <code>help</code> option 304(<samp>--help</samp>) or the <code>more-help</code> option (<samp>--more-help</samp>). <code>more-help</code> will print 305the usage text by passing it through a pager program. 306<code>more-help</code> is disabled on platforms without a working 307<code>fork(2)</code> function. The <code>PAGER</code> environment variable is 308used to select the program, defaulting to <samp>more</samp>. Both will exit 309with a status code of 0. 310</p> 311<div class="example"> 312<pre class="example">ntpd - NTP daemon program - Ver. 4.2.8p15 313Usage: ntpd [ -<flag> [<val>] | --<name>[{=| }<val>] ]... \ 314 [ <server1> ... <serverN> ] 315 Flg Arg Option-Name Description 316 -4 no ipv4 Force IPv4 DNS name resolution 317 - prohibits the option 'ipv6' 318 -6 no ipv6 Force IPv6 DNS name resolution 319 - prohibits the option 'ipv4' 320 -a no authreq Require crypto authentication 321 - prohibits the option 'authnoreq' 322 -A no authnoreq Do not require crypto authentication 323 - prohibits the option 'authreq' 324 -b no bcastsync Allow us to sync to broadcast servers 325 -c Str configfile configuration file name 326 -d no debug-level Increase debug verbosity level 327 - may appear multiple times 328 -D Num set-debug-level Set the debug verbosity level 329 - may appear multiple times 330 -f Str driftfile frequency drift file name 331 -g no panicgate Allow the first adjustment to be Big 332 - may appear multiple times 333 -G no force-step-once Step any initial offset correction. 334 -i --- jaildir built without --enable-clockctl or --enable-linuxcaps or --enable-solarisprivs 335 -I Str interface Listen on an interface name or address 336 - may appear multiple times 337 -k Str keyfile path to symmetric keys 338 -l Str logfile path to the log file 339 -L no novirtualips Do not listen to virtual interfaces 340 -n no nofork Do not fork 341 - prohibits the option 'wait-sync' 342 -N no nice Run at high priority 343 -p Str pidfile path to the PID file 344 -P Num priority Process priority 345 -q no quit Set the time and quit 346 - prohibits these options: 347 saveconfigquit 348 wait-sync 349 -r Str propagationdelay Broadcast/propagation delay 350 Str saveconfigquit Save parsed configuration and quit 351 - prohibits these options: 352 quit 353 wait-sync 354 -s Str statsdir Statistics file location 355 -t Str trustedkey Trusted key number 356 - may appear multiple times 357 -u --- user built without --enable-clockctl or --enable-linuxcaps or --enable-solarisprivs 358 -U Num updateinterval interval in seconds between scans for new or dropped interfaces 359 Str var make ARG an ntp variable (RW) 360 - may appear multiple times 361 Str dvar make ARG an ntp variable (RW|DEF) 362 - may appear multiple times 363 -w Num wait-sync Seconds to wait for first clock sync 364 - prohibits these options: 365 nofork 366 quit 367 saveconfigquit 368 -x no slew Slew up to 600 seconds 369 opt version output version information and exit 370 -? no help display extended usage information and exit 371 -! no more-help extended usage information passed thru pager 372 373Options are specified by doubled hyphens and their name or by a single 374hyphen and the flag character. 375 376 377The following option preset mechanisms are supported: 378 - examining environment variables named NTPD_* 379 380Please send bug reports to: <http://bugs.ntp.org, bugs@ntp.org> 381</pre></div> 382 383<hr> 384<a name="ntpd-ipv4"></a> 385<div class="header"> 386<p> 387Next: <a href="#ntpd-ipv6" accesskey="n" rel="next">ntpd ipv6</a>, Previous: <a href="#ntpd-usage" accesskey="p" rel="prev">ntpd usage</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 388</div> 389<a name="ipv4-option-_0028_002d4_0029"></a> 390<h4 class="subsection">1.1.2 ipv4 option (-4)</h4> 391<a name="index-ntpd_002dipv4"></a> 392 393<p>This is the “force ipv4 dns name resolution” option. 394</p> 395<p>This option has some usage constraints. It: 396</p><ul> 397<li> must not appear in combination with any of the following options: 398ipv6. 399</li></ul> 400 401<p>Force DNS resolution of following host names on the command line 402to the IPv4 namespace. 403</p><hr> 404<a name="ntpd-ipv6"></a> 405<div class="header"> 406<p> 407Next: <a href="#ntpd-authreq" accesskey="n" rel="next">ntpd authreq</a>, Previous: <a href="#ntpd-ipv4" accesskey="p" rel="prev">ntpd ipv4</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 408</div> 409<a name="ipv6-option-_0028_002d6_0029"></a> 410<h4 class="subsection">1.1.3 ipv6 option (-6)</h4> 411<a name="index-ntpd_002dipv6"></a> 412 413<p>This is the “force ipv6 dns name resolution” option. 414</p> 415<p>This option has some usage constraints. It: 416</p><ul> 417<li> must not appear in combination with any of the following options: 418ipv4. 419</li></ul> 420 421<p>Force DNS resolution of following host names on the command line 422to the IPv6 namespace. 423</p><hr> 424<a name="ntpd-authreq"></a> 425<div class="header"> 426<p> 427Next: <a href="#ntpd-authnoreq" accesskey="n" rel="next">ntpd authnoreq</a>, Previous: <a href="#ntpd-ipv6" accesskey="p" rel="prev">ntpd ipv6</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 428</div> 429<a name="authreq-option-_0028_002da_0029"></a> 430<h4 class="subsection">1.1.4 authreq option (-a)</h4> 431<a name="index-ntpd_002dauthreq"></a> 432 433<p>This is the “require crypto authentication” option. 434</p> 435<p>This option has some usage constraints. It: 436</p><ul> 437<li> must not appear in combination with any of the following options: 438authnoreq. 439</li></ul> 440 441<p>Require cryptographic authentication for broadcast client, 442multicast client and symmetric passive associations. 443This is the default. 444</p><hr> 445<a name="ntpd-authnoreq"></a> 446<div class="header"> 447<p> 448Next: <a href="#ntpd-configfile" accesskey="n" rel="next">ntpd configfile</a>, Previous: <a href="#ntpd-authreq" accesskey="p" rel="prev">ntpd authreq</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 449</div> 450<a name="authnoreq-option-_0028_002dA_0029"></a> 451<h4 class="subsection">1.1.5 authnoreq option (-A)</h4> 452<a name="index-ntpd_002dauthnoreq"></a> 453 454<p>This is the “do not require crypto authentication” option. 455</p> 456<p>This option has some usage constraints. It: 457</p><ul> 458<li> must not appear in combination with any of the following options: 459authreq. 460</li></ul> 461 462<p>Do not require cryptographic authentication for broadcast client, 463multicast client and symmetric passive associations. 464This is almost never a good idea. 465</p><hr> 466<a name="ntpd-configfile"></a> 467<div class="header"> 468<p> 469Next: <a href="#ntpd-driftfile" accesskey="n" rel="next">ntpd driftfile</a>, Previous: <a href="#ntpd-authnoreq" accesskey="p" rel="prev">ntpd authnoreq</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 470</div> 471<a name="configfile-option-_0028_002dc_0029"></a> 472<h4 class="subsection">1.1.6 configfile option (-c)</h4> 473<a name="index-ntpd_002dconfigfile"></a> 474 475<p>This is the “configuration file name” option. 476This option takes a string argument. 477The name and path of the configuration file, 478<samp>/etc/ntp.conf</samp> 479by default. 480</p><hr> 481<a name="ntpd-driftfile"></a> 482<div class="header"> 483<p> 484Next: <a href="#ntpd-panicgate" accesskey="n" rel="next">ntpd panicgate</a>, Previous: <a href="#ntpd-configfile" accesskey="p" rel="prev">ntpd configfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 485</div> 486<a name="driftfile-option-_0028_002df_0029"></a> 487<h4 class="subsection">1.1.7 driftfile option (-f)</h4> 488<a name="index-ntpd_002ddriftfile"></a> 489 490<p>This is the “frequency drift file name” option. 491This option takes a string argument. 492The name and path of the frequency file, 493<samp>/etc/ntp.drift</samp> 494by default. 495This is the same operation as the 496<code>driftfile</code> <kbd>driftfile</kbd> 497configuration specification in the 498<samp>/etc/ntp.conf</samp> 499file. 500</p><hr> 501<a name="ntpd-panicgate"></a> 502<div class="header"> 503<p> 504Next: <a href="#ntpd-force_002dstep_002donce" accesskey="n" rel="next">ntpd force-step-once</a>, Previous: <a href="#ntpd-driftfile" accesskey="p" rel="prev">ntpd driftfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 505</div> 506<a name="panicgate-option-_0028_002dg_0029"></a> 507<h4 class="subsection">1.1.8 panicgate option (-g)</h4> 508<a name="index-ntpd_002dpanicgate"></a> 509 510<p>This is the “allow the first adjustment to be big” option. 511</p> 512<p>This option has some usage constraints. It: 513</p><ul> 514<li> may appear an unlimited number of times. 515</li></ul> 516 517<p>Normally, 518<code>ntpd</code> 519exits with a message to the system log if the offset exceeds the panic threshold, which is 1000 s by default. This option allows the time to be set to any value without restriction; however, this can happen only once. If the threshold is exceeded after that, 520<code>ntpd</code> 521will exit with a message to the system log. This option can be used with the 522<code>-q</code> 523and 524<code>-x</code> 525options. 526See the 527<code>tinker</code> 528configuration file directive for other options. 529</p><hr> 530<a name="ntpd-force_002dstep_002donce"></a> 531<div class="header"> 532<p> 533Next: <a href="#ntpd-jaildir" accesskey="n" rel="next">ntpd jaildir</a>, Previous: <a href="#ntpd-panicgate" accesskey="p" rel="prev">ntpd panicgate</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 534</div> 535<a name="force_002dstep_002donce-option-_0028_002dG_0029"></a> 536<h4 class="subsection">1.1.9 force-step-once option (-G)</h4> 537<a name="index-ntpd_002dforce_002dstep_002donce"></a> 538 539<p>This is the “step any initial offset correction.” option. 540Normally, 541<code>ntpd</code> 542steps the time if the time offset exceeds the step threshold, 543which is 128 ms by default, and otherwise slews the time. 544This option forces the initial offset correction to be stepped, 545so the highest time accuracy can be achieved quickly. 546However, this may also cause the time to be stepped back 547so this option must not be used if 548applications requiring monotonic time are running. 549See the <code>tinker</code> configuration file directive for other options. 550</p><hr> 551<a name="ntpd-jaildir"></a> 552<div class="header"> 553<p> 554Next: <a href="#ntpd-interface" accesskey="n" rel="next">ntpd interface</a>, Previous: <a href="#ntpd-force_002dstep_002donce" accesskey="p" rel="prev">ntpd force-step-once</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 555</div> 556<a name="jaildir-option-_0028_002di_0029"></a> 557<h4 class="subsection">1.1.10 jaildir option (-i)</h4> 558<a name="index-ntpd_002djaildir"></a> 559 560<p>This is the “jail directory” option. 561This option takes a string argument. 562</p> 563<p>This option has some usage constraints. It: 564</p><ul> 565<li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation. 566</li></ul> 567 568<p>Chroot the server to the directory 569<kbd>jaildir</kbd> 570. 571This option also implies that the server attempts to drop root privileges at startup. 572You may need to also specify a 573<code>-u</code> 574option. 575This option is only available if the OS supports adjusting the clock 576without full root privileges. 577This option is supported under NetBSD (configure with 578<code>--enable-clockctl</code>) or Linux (configure with 579<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>). 580</p><hr> 581<a name="ntpd-interface"></a> 582<div class="header"> 583<p> 584Next: <a href="#ntpd-keyfile" accesskey="n" rel="next">ntpd keyfile</a>, Previous: <a href="#ntpd-jaildir" accesskey="p" rel="prev">ntpd jaildir</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 585</div> 586<a name="interface-option-_0028_002dI_0029"></a> 587<h4 class="subsection">1.1.11 interface option (-I)</h4> 588<a name="index-ntpd_002dinterface"></a> 589 590<p>This is the “listen on an interface name or address” option. 591This option takes a string argument <samp>iface</samp>. 592</p> 593<p>This option has some usage constraints. It: 594</p><ul> 595<li> may appear an unlimited number of times. 596</li></ul> 597 598<p>Open the network address given, or all the addresses associated with the 599given interface name. This option may appear multiple times. This option 600also implies not opening other addresses, except wildcard and localhost. 601This option is deprecated. Please consider using the configuration file 602<code>interface</code> command, which is more versatile. 603</p><hr> 604<a name="ntpd-keyfile"></a> 605<div class="header"> 606<p> 607Next: <a href="#ntpd-logfile" accesskey="n" rel="next">ntpd logfile</a>, Previous: <a href="#ntpd-interface" accesskey="p" rel="prev">ntpd interface</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 608</div> 609<a name="keyfile-option-_0028_002dk_0029"></a> 610<h4 class="subsection">1.1.12 keyfile option (-k)</h4> 611<a name="index-ntpd_002dkeyfile"></a> 612 613<p>This is the “path to symmetric keys” option. 614This option takes a string argument. 615Specify the name and path of the symmetric key file. 616<samp>/etc/ntp.keys</samp> 617is the default. 618This is the same operation as the 619<code>keys</code> <kbd>keyfile</kbd> 620configuration file directive. 621</p><hr> 622<a name="ntpd-logfile"></a> 623<div class="header"> 624<p> 625Next: <a href="#ntpd-novirtualips" accesskey="n" rel="next">ntpd novirtualips</a>, Previous: <a href="#ntpd-keyfile" accesskey="p" rel="prev">ntpd keyfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 626</div> 627<a name="logfile-option-_0028_002dl_0029"></a> 628<h4 class="subsection">1.1.13 logfile option (-l)</h4> 629<a name="index-ntpd_002dlogfile"></a> 630 631<p>This is the “path to the log file” option. 632This option takes a string argument. 633Specify the name and path of the log file. 634The default is the system log file. 635This is the same operation as the 636<code>logfile</code> <kbd>logfile</kbd> 637configuration file directive. 638</p><hr> 639<a name="ntpd-novirtualips"></a> 640<div class="header"> 641<p> 642Next: <a href="#ntpd-modifymmtimer" accesskey="n" rel="next">ntpd modifymmtimer</a>, Previous: <a href="#ntpd-logfile" accesskey="p" rel="prev">ntpd logfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 643</div> 644<a name="novirtualips-option-_0028_002dL_0029"></a> 645<h4 class="subsection">1.1.14 novirtualips option (-L)</h4> 646<a name="index-ntpd_002dnovirtualips"></a> 647 648<p>This is the “do not listen to virtual interfaces” option. 649Do not listen to virtual interfaces, defined as those with 650names containing a colon. This option is deprecated. Please 651consider using the configuration file <code>interface</code> command, which 652is more versatile. 653</p><hr> 654<a name="ntpd-modifymmtimer"></a> 655<div class="header"> 656<p> 657Next: <a href="#ntpd-nice" accesskey="n" rel="next">ntpd nice</a>, Previous: <a href="#ntpd-novirtualips" accesskey="p" rel="prev">ntpd novirtualips</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 658</div> 659<a name="modifymmtimer-option-_0028_002dM_0029"></a> 660<h4 class="subsection">1.1.15 modifymmtimer option (-M)</h4> 661<a name="index-ntpd_002dmodifymmtimer"></a> 662 663<p>This is the “modify multimedia timer (windows only)” option. 664</p> 665<p>This option has some usage constraints. It: 666</p><ul> 667<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation. 668</li></ul> 669 670<p>Set the Windows Multimedia Timer to highest resolution. This 671ensures the resolution does not change while ntpd is running, 672avoiding timekeeping glitches associated with changes. 673</p><hr> 674<a name="ntpd-nice"></a> 675<div class="header"> 676<p> 677Next: <a href="#ntpd-pidfile" accesskey="n" rel="next">ntpd pidfile</a>, Previous: <a href="#ntpd-modifymmtimer" accesskey="p" rel="prev">ntpd modifymmtimer</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 678</div> 679<a name="nice-option-_0028_002dN_0029"></a> 680<h4 class="subsection">1.1.16 nice option (-N)</h4> 681<a name="index-ntpd_002dnice"></a> 682 683<p>This is the “run at high priority” option. 684To the extent permitted by the operating system, run 685<code>ntpd</code> 686at the highest priority. 687</p><hr> 688<a name="ntpd-pidfile"></a> 689<div class="header"> 690<p> 691Next: <a href="#ntpd-priority" accesskey="n" rel="next">ntpd priority</a>, Previous: <a href="#ntpd-nice" accesskey="p" rel="prev">ntpd nice</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 692</div> 693<a name="pidfile-option-_0028_002dp_0029"></a> 694<h4 class="subsection">1.1.17 pidfile option (-p)</h4> 695<a name="index-ntpd_002dpidfile"></a> 696 697<p>This is the “path to the pid file” option. 698This option takes a string argument. 699Specify the name and path of the file used to record 700<code>ntpd</code>’s 701process ID. 702This is the same operation as the 703<code>pidfile</code> <kbd>pidfile</kbd> 704configuration file directive. 705</p><hr> 706<a name="ntpd-priority"></a> 707<div class="header"> 708<p> 709Next: <a href="#ntpd-quit" accesskey="n" rel="next">ntpd quit</a>, Previous: <a href="#ntpd-pidfile" accesskey="p" rel="prev">ntpd pidfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 710</div> 711<a name="priority-option-_0028_002dP_0029"></a> 712<h4 class="subsection">1.1.18 priority option (-P)</h4> 713<a name="index-ntpd_002dpriority"></a> 714 715<p>This is the “process priority” option. 716This option takes a number argument. 717To the extent permitted by the operating system, run 718<code>ntpd</code> 719at the specified 720<code>sched_setscheduler(SCHED_FIFO)</code> 721priority. 722</p><hr> 723<a name="ntpd-quit"></a> 724<div class="header"> 725<p> 726Next: <a href="#ntpd-propagationdelay" accesskey="n" rel="next">ntpd propagationdelay</a>, Previous: <a href="#ntpd-priority" accesskey="p" rel="prev">ntpd priority</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 727</div> 728<a name="quit-option-_0028_002dq_0029"></a> 729<h4 class="subsection">1.1.19 quit option (-q)</h4> 730<a name="index-ntpd_002dquit"></a> 731 732<p>This is the “set the time and quit” option. 733</p> 734<p>This option has some usage constraints. It: 735</p><ul> 736<li> must not appear in combination with any of the following options: 737saveconfigquit, wait-sync. 738</li></ul> 739 740<p><code>ntpd</code> 741will not daemonize and will exit after the clock is first 742synchronized. This behavior mimics that of the 743<code>ntpdate</code> 744program, which will soon be replaced with a shell script. 745The 746<code>-g</code> 747and 748<code>-x</code> 749options can be used with this option. 750Note: The kernel time discipline is disabled with this option. 751</p><hr> 752<a name="ntpd-propagationdelay"></a> 753<div class="header"> 754<p> 755Next: <a href="#ntpd-saveconfigquit" accesskey="n" rel="next">ntpd saveconfigquit</a>, Previous: <a href="#ntpd-quit" accesskey="p" rel="prev">ntpd quit</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 756</div> 757<a name="propagationdelay-option-_0028_002dr_0029"></a> 758<h4 class="subsection">1.1.20 propagationdelay option (-r)</h4> 759<a name="index-ntpd_002dpropagationdelay"></a> 760 761<p>This is the “broadcast/propagation delay” option. 762This option takes a string argument. 763Specify the default propagation delay from the broadcast/multicast server to this client. This is necessary only if the delay cannot be computed automatically by the protocol. 764</p><hr> 765<a name="ntpd-saveconfigquit"></a> 766<div class="header"> 767<p> 768Next: <a href="#ntpd-statsdir" accesskey="n" rel="next">ntpd statsdir</a>, Previous: <a href="#ntpd-propagationdelay" accesskey="p" rel="prev">ntpd propagationdelay</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 769</div> 770<a name="saveconfigquit-option"></a> 771<h4 class="subsection">1.1.21 saveconfigquit option</h4> 772<a name="index-ntpd_002dsaveconfigquit"></a> 773 774<p>This is the “save parsed configuration and quit” option. 775This option takes a string argument. 776</p> 777<p>This option has some usage constraints. It: 778</p><ul> 779<li> must be compiled in by defining <code>SAVECONFIG</code> during the compilation. 780</li><li> must not appear in combination with any of the following options: 781quit, wait-sync. 782</li></ul> 783 784<p>Cause <code>ntpd</code> to parse its startup configuration file and save an 785equivalent to the given filename and exit. This option was 786designed for automated testing. 787</p><hr> 788<a name="ntpd-statsdir"></a> 789<div class="header"> 790<p> 791Next: <a href="#ntpd-trustedkey" accesskey="n" rel="next">ntpd trustedkey</a>, Previous: <a href="#ntpd-saveconfigquit" accesskey="p" rel="prev">ntpd saveconfigquit</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 792</div> 793<a name="statsdir-option-_0028_002ds_0029"></a> 794<h4 class="subsection">1.1.22 statsdir option (-s)</h4> 795<a name="index-ntpd_002dstatsdir"></a> 796 797<p>This is the “statistics file location” option. 798This option takes a string argument. 799Specify the directory path for files created by the statistics facility. 800This is the same operation as the 801<code>statsdir</code> <kbd>statsdir</kbd> 802configuration file directive. 803</p><hr> 804<a name="ntpd-trustedkey"></a> 805<div class="header"> 806<p> 807Next: <a href="#ntpd-user" accesskey="n" rel="next">ntpd user</a>, Previous: <a href="#ntpd-statsdir" accesskey="p" rel="prev">ntpd statsdir</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 808</div> 809<a name="trustedkey-option-_0028_002dt_0029"></a> 810<h4 class="subsection">1.1.23 trustedkey option (-t)</h4> 811<a name="index-ntpd_002dtrustedkey"></a> 812 813<p>This is the “trusted key number” option. 814This option takes a string argument <samp>tkey</samp>. 815</p> 816<p>This option has some usage constraints. It: 817</p><ul> 818<li> may appear an unlimited number of times. 819</li></ul> 820 821<p>Add the specified key number to the trusted key list. 822</p><hr> 823<a name="ntpd-user"></a> 824<div class="header"> 825<p> 826Next: <a href="#ntpd-updateinterval" accesskey="n" rel="next">ntpd updateinterval</a>, Previous: <a href="#ntpd-trustedkey" accesskey="p" rel="prev">ntpd trustedkey</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 827</div> 828<a name="user-option-_0028_002du_0029"></a> 829<h4 class="subsection">1.1.24 user option (-u)</h4> 830<a name="index-ntpd_002duser"></a> 831 832<p>This is the “run as userid (or userid:groupid)” option. 833This option takes a string argument. 834</p> 835<p>This option has some usage constraints. It: 836</p><ul> 837<li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation. 838</li></ul> 839 840<p>Specify a user, and optionally a group, to switch to. 841This option is only available if the OS supports adjusting the clock 842without full root privileges. 843This option is supported under NetBSD (configure with 844<code>--enable-clockctl</code>) or Linux (configure with 845<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>). 846</p><hr> 847<a name="ntpd-updateinterval"></a> 848<div class="header"> 849<p> 850Next: <a href="#ntpd-wait_002dsync" accesskey="n" rel="next">ntpd wait-sync</a>, Previous: <a href="#ntpd-user" accesskey="p" rel="prev">ntpd user</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 851</div> 852<a name="updateinterval-option-_0028_002dU_0029"></a> 853<h4 class="subsection">1.1.25 updateinterval option (-U)</h4> 854<a name="index-ntpd_002dupdateinterval"></a> 855 856<p>This is the “interval in seconds between scans for new or dropped interfaces” option. 857This option takes a number argument. 858Give the time in seconds between two scans for new or dropped interfaces. 859For systems with routing socket support the scans will be performed shortly after the interface change 860has been detected by the system. 861Use 0 to disable scanning. 60 seconds is the minimum time between scans. 862</p><hr> 863<a name="ntpd-wait_002dsync"></a> 864<div class="header"> 865<p> 866Next: <a href="#ntpd-slew" accesskey="n" rel="next">ntpd slew</a>, Previous: <a href="#ntpd-updateinterval" accesskey="p" rel="prev">ntpd updateinterval</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 867</div> 868<a name="wait_002dsync-option-_0028_002dw_0029"></a> 869<h4 class="subsection">1.1.26 wait-sync option (-w)</h4> 870<a name="index-ntpd_002dwait_002dsync"></a> 871 872<p>This is the “seconds to wait for first clock sync” option. 873This option takes a number argument. 874</p> 875<p>This option has some usage constraints. It: 876</p><ul> 877<li> must be compiled in by defining <code>HAVE_WORKING_FORK</code> during the compilation. 878</li><li> must not appear in combination with any of the following options: 879nofork, quit, saveconfigquit. 880</li></ul> 881 882<p>If greater than zero, alters <code>ntpd</code>’s behavior when forking to 883daemonize. Instead of exiting with status 0 immediately after 884the fork, the parent waits up to the specified number of 885seconds for the child to first synchronize the clock. The exit 886status is zero (success) if the clock was synchronized, 887otherwise it is <code>ETIMEDOUT</code>. 888This provides the option for a script starting <code>ntpd</code> to easily 889wait for the first set of the clock before proceeding. 890</p><hr> 891<a name="ntpd-slew"></a> 892<div class="header"> 893<p> 894Next: <a href="#ntpd-usepcc" accesskey="n" rel="next">ntpd usepcc</a>, Previous: <a href="#ntpd-wait_002dsync" accesskey="p" rel="prev">ntpd wait-sync</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 895</div> 896<a name="slew-option-_0028_002dx_0029"></a> 897<h4 class="subsection">1.1.27 slew option (-x)</h4> 898<a name="index-ntpd_002dslew"></a> 899 900<p>This is the “slew up to 600 seconds” option. 901Normally, the time is slewed if the offset is less than the step threshold, which is 128 ms by default, and stepped if above the threshold. 902This option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually. 903Note: Since the slew rate of typical Unix kernels is limited to 0.5 ms/s, each second of adjustment requires an amortization interval of 2000 s. 904Thus, an adjustment as much as 600 s will take almost 14 days to complete. 905This option can be used with the 906<code>-g</code> 907and 908<code>-q</code> 909options. 910See the 911<code>tinker</code> 912configuration file directive for other options. 913Note: The kernel time discipline is disabled with this option. 914</p><hr> 915<a name="ntpd-usepcc"></a> 916<div class="header"> 917<p> 918Next: <a href="#ntpd-pccfreq" accesskey="n" rel="next">ntpd pccfreq</a>, Previous: <a href="#ntpd-slew" accesskey="p" rel="prev">ntpd slew</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 919</div> 920<a name="usepcc-option"></a> 921<h4 class="subsection">1.1.28 usepcc option</h4> 922<a name="index-ntpd_002dusepcc"></a> 923 924<p>This is the “use cpu cycle counter (windows only)” option. 925</p> 926<p>This option has some usage constraints. It: 927</p><ul> 928<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation. 929</li></ul> 930 931<p>Attempt to substitute the CPU counter for <code>QueryPerformanceCounter</code>. 932The CPU counter and <code>QueryPerformanceCounter</code> are compared, and if 933they have the same frequency, the CPU counter (RDTSC on x86) is 934used directly, saving the overhead of a system call. 935</p><hr> 936<a name="ntpd-pccfreq"></a> 937<div class="header"> 938<p> 939Next: <a href="#ntpd-mdns" accesskey="n" rel="next">ntpd mdns</a>, Previous: <a href="#ntpd-usepcc" accesskey="p" rel="prev">ntpd usepcc</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 940</div> 941<a name="pccfreq-option"></a> 942<h4 class="subsection">1.1.29 pccfreq option</h4> 943<a name="index-ntpd_002dpccfreq"></a> 944 945<p>This is the “force cpu cycle counter use (windows only)” option. 946This option takes a string argument. 947</p> 948<p>This option has some usage constraints. It: 949</p><ul> 950<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation. 951</li></ul> 952 953<p>Force substitution the CPU counter for <code>QueryPerformanceCounter</code>. 954The CPU counter (RDTSC on x86) is used unconditionally with the 955given frequency (in Hz). 956</p><hr> 957<a name="ntpd-mdns"></a> 958<div class="header"> 959<p> 960Next: <a href="#ntpd-config" accesskey="n" rel="next">ntpd config</a>, Previous: <a href="#ntpd-pccfreq" accesskey="p" rel="prev">ntpd pccfreq</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 961</div> 962<a name="mdns-option-_0028_002dm_0029"></a> 963<h4 class="subsection">1.1.30 mdns option (-m)</h4> 964<a name="index-ntpd_002dmdns"></a> 965 966<p>This is the “register with mdns as a ntp server” option. 967</p> 968<p>This option has some usage constraints. It: 969</p><ul> 970<li> must be compiled in by defining <code>HAVE_DNSREGISTRATION</code> during the compilation. 971</li></ul> 972 973<p>Registers as an NTP server with the local mDNS server which allows 974the server to be discovered via mDNS client lookup. 975</p> 976 977<hr> 978<a name="ntpd-config"></a> 979<div class="header"> 980<p> 981Next: <a href="#ntpd-exit-status" accesskey="n" rel="next">ntpd exit status</a>, Previous: <a href="#ntpd-mdns" accesskey="p" rel="prev">ntpd mdns</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 982</div> 983<a name="presetting_002fconfiguring-ntpd"></a> 984<h4 class="subsection">1.1.31 presetting/configuring ntpd</h4> 985 986<p>Any option that is not marked as <i>not presettable</i> may be preset by 987loading values from environment variables named <code>NTPD</code> and <code>NTPD_<OPTION_NAME></code>. <code><OPTION_NAME></code> must be one of 988the options listed above in upper case and segmented with underscores. 989The <code>NTPD</code> variable will be tokenized and parsed like 990the command line. The remaining variables are tested for existence and their 991values are treated like option arguments. 992</p> 993 994<p>The command line options relating to configuration and/or usage help are: 995</p> 996<a name="version-_0028_002d_0029"></a> 997<h4 class="subsubheading">version (-)</h4> 998 999<p>Print the program version to standard out, optionally with licensing 1000information, then exit 0. The optional argument specifies how much licensing 1001detail to provide. The default is to print just the version. The licensing infomation may be selected with an option argument. 1002Only the first letter of the argument is examined: 1003</p> 1004<dl compact="compact"> 1005<dt>‘<samp>version</samp>’</dt> 1006<dd><p>Only print the version. This is the default. 1007</p></dd> 1008<dt>‘<samp>copyright</samp>’</dt> 1009<dd><p>Name the copyright usage licensing terms. 1010</p></dd> 1011<dt>‘<samp>verbose</samp>’</dt> 1012<dd><p>Print the full copyright usage licensing terms. 1013</p></dd> 1014</dl> 1015 1016<hr> 1017<a name="ntpd-exit-status"></a> 1018<div class="header"> 1019<p> 1020Next: <a href="#ntpd-Usage" accesskey="n" rel="next">ntpd Usage</a>, Previous: <a href="#ntpd-config" accesskey="p" rel="prev">ntpd config</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 1021</div> 1022<a name="ntpd-exit-status-1"></a> 1023<h4 class="subsection">1.1.32 ntpd exit status</h4> 1024 1025<p>One of the following exit values will be returned: 1026</p><dl compact="compact"> 1027<dt>‘<samp>0 (EXIT_SUCCESS)</samp>’</dt> 1028<dd><p>Successful program execution. 1029</p></dd> 1030<dt>‘<samp>1 (EXIT_FAILURE)</samp>’</dt> 1031<dd><p>The operation failed or the command syntax was not valid. 1032</p></dd> 1033</dl> 1034<hr> 1035<a name="ntpd-Usage"></a> 1036<div class="header"> 1037<p> 1038Next: <a href="#ntpd-Files" accesskey="n" rel="next">ntpd Files</a>, Previous: <a href="#ntpd-exit-status" accesskey="p" rel="prev">ntpd exit status</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 1039</div> 1040<a name="ntpd-Usage-1"></a> 1041<h4 class="subsection">1.1.33 ntpd Usage</h4> 1042<hr> 1043<a name="ntpd-Files"></a> 1044<div class="header"> 1045<p> 1046Next: <a href="#ntpd-See-Also" accesskey="n" rel="next">ntpd See Also</a>, Previous: <a href="#ntpd-Usage" accesskey="p" rel="prev">ntpd Usage</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 1047</div> 1048<a name="ntpd-Files-1"></a> 1049<h4 class="subsection">1.1.34 ntpd Files</h4> 1050<hr> 1051<a name="ntpd-See-Also"></a> 1052<div class="header"> 1053<p> 1054Next: <a href="#ntpd-Bugs" accesskey="n" rel="next">ntpd Bugs</a>, Previous: <a href="#ntpd-Files" accesskey="p" rel="prev">ntpd Files</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 1055</div> 1056<a name="ntpd-See-Also-1"></a> 1057<h4 class="subsection">1.1.35 ntpd See Also</h4> 1058<hr> 1059<a name="ntpd-Bugs"></a> 1060<div class="header"> 1061<p> 1062Next: <a href="#ntpd-Notes" accesskey="n" rel="next">ntpd Notes</a>, Previous: <a href="#ntpd-See-Also" accesskey="p" rel="prev">ntpd See Also</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 1063</div> 1064<a name="ntpd-Bugs-1"></a> 1065<h4 class="subsection">1.1.36 ntpd Bugs</h4> 1066<hr> 1067<a name="ntpd-Notes"></a> 1068<div class="header"> 1069<p> 1070Previous: <a href="#ntpd-Bugs" accesskey="p" rel="prev">ntpd Bugs</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p> 1071</div> 1072<a name="ntpd-Notes-1"></a> 1073<h4 class="subsection">1.1.37 ntpd Notes</h4> 1074 1075<hr> 1076<a name="Usage"></a> 1077<div class="header"> 1078<p> 1079Previous: <a href="#ntpd-Invocation" accesskey="p" rel="prev">ntpd Invocation</a>, Up: <a href="#ntpd-Description" accesskey="u" rel="up">ntpd Description</a> </p> 1080</div> 1081<a name="Usage-1"></a> 1082<h3 class="section">1.2 Usage</h3> 1083 1084<table> 1085<thead><tr><th width="23%">What</th><th width="23%">Default</th><th width="5%">Flag</th><th width="15%">Option</th></tr></thead> 1086<tr><td width="23%">configuration file</td><td width="23%"><code>/etc/ntp.conf</code></td><td width="5%"><code>-c</code></td><td width="15%"><code>conffile</code></td></tr> 1087<tr><td width="23%">frequency file</td><td width="23%">none</td><td width="5%"><code>-f</code></td><td width="15%"><code>driftfile</code></td></tr> 1088<tr><td width="23%">leapseconds file</td><td width="23%">none</td><td width="5%"></td><td width="15%"><code>leapfile</code></td></tr> 1089<tr><td width="23%">process ID file</td><td width="23%">none</td><td width="5%"><code>-p</code></td><td width="15%"><code>pidfile</code></td></tr> 1090<tr><td width="23%">log file</td><td width="23%">system log</td><td width="5%"><code>-l</code></td><td width="15%"><code>logfile</code></td></tr> 1091<tr><td width="23%">include file</td><td width="23%">none</td><td width="5%">none</td><td width="15%"><code>includefile</code></td></tr> 1092<tr><td width="23%">statistics path</td><td width="23%"><code>/var/NTP</code></td><td width="5%"><code>-s</code></td><td width="15%"><code>statsdir</code></td></tr> 1093<tr><td width="23%">keys path</td><td width="23%"><code>/usr/local/etc</code></td><td width="5%"><code>-k</code></td><td width="15%"><code>keysdir</code></td></tr> 1094</table> 1095<hr> 1096 1097 1098 1099</body> 1100</html> 1101