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46052d159aSCy Schubert<body lang="en">
47052d159aSCy Schubert<h1 class="settitle" align="center">ntpd: Network Time Protocol (NTP) Daemon User&rsquo;s Manual</h1>
48052d159aSCy Schubert
49052d159aSCy Schubert
50052d159aSCy Schubert
51052d159aSCy Schubert
52052d159aSCy Schubert
53052d159aSCy Schubert<a name="Top"></a>
54052d159aSCy Schubert<div class="header">
55052d159aSCy Schubert<p>
56052d159aSCy SchubertNext: <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> &nbsp; </p>
57052d159aSCy Schubert</div>
58052d159aSCy Schubert<a name="ntpd_003a-Network-Time-Protocol-_0028NTP_0029-Daemon-User-Manual"></a>
59052d159aSCy Schubert<h1 class="top">ntpd: Network Time Protocol (NTP) Daemon User Manual</h1>
602b15cb3dSCy Schubert
612b15cb3dSCy Schubert<p>The <code>ntpd</code> program is an operating system daemon that synchronizes the
622b15cb3dSCy Schubertsystem clock to remote NTP time servers or local reference clocks.
632b15cb3dSCy SchubertIt is a complete implementation of NTP version 4 defined by RFC-5905, but
642b15cb3dSCy Schubertalso retains compatible with version 3 defined by RFC-1305 and versions
652b15cb3dSCy Schubert1 and 2, defined by RFC-1059 and RFC-1119, respectively.
662b15cb3dSCy SchubertThe program can operate in any of several modes, including client/server,
672b15cb3dSCy Schubertsymmetric and broadcast modes, and with both symmetric-key and public-key
682b15cb3dSCy Schubertcryptography.
69052d159aSCy Schubert</p>
70*2d4e511cSCy Schubert<p>This document applies to version 4.2.8p14 of <code>ntpd</code>.
71052d159aSCy Schubert</p>
72052d159aSCy Schubert<a name="SEC_Overview"></a>
73052d159aSCy Schubert<h2 class="shortcontents-heading">Short Table of Contents</h2>
742b15cb3dSCy Schubert
75052d159aSCy Schubert<div class="shortcontents">
76052d159aSCy Schubert<ul class="no-bullet">
77052d159aSCy Schubert<li><a name="stoc-Description" href="#toc-Description">1 Description</a></li>
782b15cb3dSCy Schubert</ul>
792b15cb3dSCy Schubert</div>
802b15cb3dSCy Schubert
81052d159aSCy Schubert
82052d159aSCy Schubert<table class="menu" border="0" cellspacing="0">
83052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-Description" accesskey="1">ntpd Description</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Description
84052d159aSCy Schubert</td></tr>
85052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-Invocation" accesskey="2">ntpd Invocation</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Invoking ntpd
86052d159aSCy Schubert</td></tr>
87052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#Usage" accesskey="3">Usage</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Usage
88052d159aSCy Schubert</td></tr>
89052d159aSCy Schubert</table>
90052d159aSCy Schubert
91052d159aSCy Schubert<hr>
92052d159aSCy Schubert<a name="ntpd-Description"></a>
93052d159aSCy Schubert<div class="header">
94052d159aSCy Schubert<p>
95052d159aSCy SchubertNext: <a href="#ntpd-Invocation" accesskey="n" rel="next">ntpd Invocation</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> &nbsp; </p>
96052d159aSCy Schubert</div>
97052d159aSCy Schubert<a name="Description"></a>
98052d159aSCy Schubert<h2 class="chapter">1 Description</h2>
992b15cb3dSCy Schubert
1002b15cb3dSCy Schubert<p>The <code>ntpd</code> program ordinarily requires
101052d159aSCy Schuberta configuration file described at &lsquo;ntp.conf&rsquo;.
1022b15cb3dSCy SchubertThis configuration file contains configuration commands described on
1032b15cb3dSCy Schubertthe pages listed above.
1042b15cb3dSCy SchubertHowever a client can discover remote servers and configure them
1052b15cb3dSCy Schubertautomatically.
1062b15cb3dSCy SchubertThis makes it possible to deploy a fleet of workstations without
1072b15cb3dSCy Schubertspecifying configuration details specific to the local environment.
108052d159aSCy Schubert</p>
1092b15cb3dSCy Schubert<p>The <code>ntpd</code> program normally operates continuously while adjusting the
1102b15cb3dSCy Schubertsystem time and frequency, but in some cases this might not be
1112b15cb3dSCy Schubertpractical.
1122b15cb3dSCy SchubertWith the <code>-q</code> option <code>ntpd</code> operates as in continuous mode, but
1132b15cb3dSCy Schubertexits just after setting the clock for the first time.
1142b15cb3dSCy SchubertMost applications will probably want to specify the <code>iburst</code>
1152b15cb3dSCy Schubertoption with the <code>server</code> command.
1162b15cb3dSCy SchubertWith this option an initial volley of messages is exchanged to
117052d159aSCy Schubertgroom the data and set the clock in about ten seconds&rsquo; time.
118052d159aSCy SchubertIf nothing is heard after a few minutes&rsquo; time,
1192b15cb3dSCy Schubertthe daemon times out and exits without setting the clock.
120052d159aSCy Schubert</p>
121052d159aSCy Schubert<table class="menu" border="0" cellspacing="0">
122052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-Invocation" accesskey="1">ntpd Invocation</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
123052d159aSCy Schubert</td></tr>
124052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#Usage" accesskey="2">Usage</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
125052d159aSCy Schubert</td></tr>
126052d159aSCy Schubert</table>
1272b15cb3dSCy Schubert
128052d159aSCy Schubert<hr>
1292b15cb3dSCy Schubert<a name="ntpd-Invocation"></a>
130052d159aSCy Schubert<div class="header">
131052d159aSCy Schubert<p>
132052d159aSCy SchubertNext: <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> &nbsp; </p>
1332b15cb3dSCy Schubert</div>
134052d159aSCy Schubert<a name="Invoking-ntpd"></a>
135052d159aSCy Schubert<h3 class="section">1.1 Invoking ntpd</h3>
136052d159aSCy Schubert<a name="index-ntpd"></a>
137052d159aSCy Schubert<a name="index-NTP-daemon-program"></a>
1382b15cb3dSCy Schubert
1392b15cb3dSCy Schubert
1402b15cb3dSCy Schubert
1412b15cb3dSCy Schubert<p>The
1422b15cb3dSCy Schubert<code>ntpd</code>
1432b15cb3dSCy Schubertutility is an operating system daemon which sets
1442b15cb3dSCy Schubertand maintains the system time of day in synchronism with Internet
1452b15cb3dSCy Schubertstandard time servers.
1462b15cb3dSCy SchubertIt is a complete implementation of the
1472b15cb3dSCy SchubertNetwork Time Protocol (NTP) version 4, as defined by RFC-5905,
1482b15cb3dSCy Schubertbut also retains compatibility with
1492b15cb3dSCy Schubertversion 3, as defined by RFC-1305, and versions 1
1502b15cb3dSCy Schubertand 2, as defined by RFC-1059 and RFC-1119, respectively.
151052d159aSCy Schubert</p>
1522b15cb3dSCy Schubert<p>The
1532b15cb3dSCy Schubert<code>ntpd</code>
1542b15cb3dSCy Schubertutility does most computations in 64-bit floating point
1552b15cb3dSCy Schubertarithmetic and does relatively clumsy 64-bit fixed point operations
1562b15cb3dSCy Schubertonly when necessary to preserve the ultimate precision, about 232
1572b15cb3dSCy Schubertpicoseconds.
1582b15cb3dSCy SchubertWhile the ultimate precision is not achievable with
1592b15cb3dSCy Schubertordinary workstations and networks of today, it may be required
1602b15cb3dSCy Schubertwith future gigahertz CPU clocks and gigabit LANs.
161052d159aSCy Schubert</p>
1622b15cb3dSCy Schubert<p>Ordinarily,
1632b15cb3dSCy Schubert<code>ntpd</code>
1642b15cb3dSCy Schubertreads the
1652b15cb3dSCy Schubert<code>ntp.conf(5)</code>
1662b15cb3dSCy Schubertconfiguration file at startup time in order to determine the
1672b15cb3dSCy Schubertsynchronization sources and operating modes.
1682b15cb3dSCy SchubertIt is also possible to
1692b15cb3dSCy Schubertspecify a working, although limited, configuration entirely on the
1702b15cb3dSCy Schubertcommand line, obviating the need for a configuration file.
1712b15cb3dSCy SchubertThis may
1722b15cb3dSCy Schubertbe particularly useful when the local host is to be configured as a
1732b15cb3dSCy Schubertbroadcast/multicast client, with all peers being determined by
1742b15cb3dSCy Schubertlistening to broadcasts at run time.
175052d159aSCy Schubert</p>
1762b15cb3dSCy Schubert<p>If NetInfo support is built into
1772b15cb3dSCy Schubert<code>ntpd</code>
1782b15cb3dSCy Schubertthen
1792b15cb3dSCy Schubert<code>ntpd</code>
1802b15cb3dSCy Schubertwill attempt to read its configuration from the
1812b15cb3dSCy SchubertNetInfo if the default
1822b15cb3dSCy Schubert<code>ntp.conf(5)</code>
1832b15cb3dSCy Schubertfile cannot be read and no file is
1842b15cb3dSCy Schubertspecified by the
1852b15cb3dSCy Schubert<code>-c</code>
1862b15cb3dSCy Schubertoption.
187052d159aSCy Schubert</p>
1882b15cb3dSCy Schubert<p>Various internal
1892b15cb3dSCy Schubert<code>ntpd</code>
1902b15cb3dSCy Schubertvariables can be displayed and
1912b15cb3dSCy Schubertconfiguration options altered while the
1922b15cb3dSCy Schubert<code>ntpd</code>
1932b15cb3dSCy Schubertis running
1942b15cb3dSCy Schubertusing the
1952b15cb3dSCy Schubert<code>ntpq(1ntpqmdoc)</code>
1962b15cb3dSCy Schubertand
1972b15cb3dSCy Schubert<code>ntpdc(1ntpdcmdoc)</code>
1982b15cb3dSCy Schubertutility programs.
199052d159aSCy Schubert</p>
2002b15cb3dSCy Schubert<p>When
2012b15cb3dSCy Schubert<code>ntpd</code>
2022b15cb3dSCy Schubertstarts it looks at the value of
2032b15cb3dSCy Schubert<code>umask(2)</code>,
2042b15cb3dSCy Schubertand if zero
2052b15cb3dSCy Schubert<code>ntpd</code>
2062b15cb3dSCy Schubertwill set the
2072b15cb3dSCy Schubert<code>umask(2)</code>
2082b15cb3dSCy Schubertto 022.
209052d159aSCy Schubert</p>
2102b15cb3dSCy Schubert<p>This section was generated by <strong>AutoGen</strong>,
2112b15cb3dSCy Schubertusing the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntpd</code> program.
2122b15cb3dSCy SchubertThis software is released under the NTP license, &lt;http://ntp.org/license&gt;.
213052d159aSCy Schubert</p>
214052d159aSCy Schubert<table class="menu" border="0" cellspacing="0">
215052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-usage" accesskey="1">ntpd usage</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">ntpd help/usage (<samp>--help</samp>)
216052d159aSCy Schubert</td></tr>
217052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-ipv4" accesskey="2">ntpd ipv4</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">ipv4 option (-4)
218052d159aSCy Schubert</td></tr>
219052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-ipv6" accesskey="3">ntpd ipv6</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">ipv6 option (-6)
220052d159aSCy Schubert</td></tr>
221052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-authreq" accesskey="4">ntpd authreq</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">authreq option (-a)
222052d159aSCy Schubert</td></tr>
223052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-authnoreq" accesskey="5">ntpd authnoreq</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">authnoreq option (-A)
224052d159aSCy Schubert</td></tr>
225052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-configfile" accesskey="6">ntpd configfile</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">configfile option (-c)
226052d159aSCy Schubert</td></tr>
227052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-driftfile" accesskey="7">ntpd driftfile</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">driftfile option (-f)
228052d159aSCy Schubert</td></tr>
229052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-panicgate" accesskey="8">ntpd panicgate</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">panicgate option (-g)
230052d159aSCy Schubert</td></tr>
231052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-force_002dstep_002donce" accesskey="9">ntpd force-step-once</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">force-step-once option (-G)
232052d159aSCy Schubert</td></tr>
233052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-jaildir">ntpd jaildir</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">jaildir option (-i)
234052d159aSCy Schubert</td></tr>
235052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-interface">ntpd interface</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">interface option (-I)
236052d159aSCy Schubert</td></tr>
237052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-keyfile">ntpd keyfile</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">keyfile option (-k)
238052d159aSCy Schubert</td></tr>
239052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-logfile">ntpd logfile</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">logfile option (-l)
240052d159aSCy Schubert</td></tr>
241052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-novirtualips">ntpd novirtualips</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">novirtualips option (-L)
242052d159aSCy Schubert</td></tr>
243052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">modifymmtimer option (-M)
244052d159aSCy Schubert</td></tr>
245052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-nice">ntpd nice</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">nice option (-N)
246052d159aSCy Schubert</td></tr>
247052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-pidfile">ntpd pidfile</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">pidfile option (-p)
248052d159aSCy Schubert</td></tr>
249052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-priority">ntpd priority</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">priority option (-P)
250052d159aSCy Schubert</td></tr>
251052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-quit">ntpd quit</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">quit option (-q)
252052d159aSCy Schubert</td></tr>
253052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-propagationdelay">ntpd propagationdelay</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">propagationdelay option (-r)
254052d159aSCy Schubert</td></tr>
255052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">saveconfigquit option
256052d159aSCy Schubert</td></tr>
257052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-statsdir">ntpd statsdir</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">statsdir option (-s)
258052d159aSCy Schubert</td></tr>
259052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-trustedkey">ntpd trustedkey</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">trustedkey option (-t)
260052d159aSCy Schubert</td></tr>
261052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-user">ntpd user</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">user option (-u)
262052d159aSCy Schubert</td></tr>
263052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-updateinterval">ntpd updateinterval</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">updateinterval option (-U)
264052d159aSCy Schubert</td></tr>
265052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-wait_002dsync">ntpd wait-sync</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">wait-sync option (-w)
266052d159aSCy Schubert</td></tr>
267052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-slew">ntpd slew</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">slew option (-x)
268052d159aSCy Schubert</td></tr>
269052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-usepcc">ntpd usepcc</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">usepcc option
270052d159aSCy Schubert</td></tr>
271052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-pccfreq">ntpd pccfreq</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">pccfreq option
272052d159aSCy Schubert</td></tr>
273052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-mdns">ntpd mdns</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">mdns option (-m)
274052d159aSCy Schubert</td></tr>
275052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-config">ntpd config</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">presetting/configuring ntpd
276052d159aSCy Schubert</td></tr>
277052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-exit-status">ntpd exit status</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">exit status
278052d159aSCy Schubert</td></tr>
279052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-Usage">ntpd Usage</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Usage
280052d159aSCy Schubert</td></tr>
281052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-Files">ntpd Files</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Files
282052d159aSCy Schubert</td></tr>
283052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-See-Also">ntpd See Also</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">See Also
284052d159aSCy Schubert</td></tr>
285052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-Bugs">ntpd Bugs</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Bugs
286052d159aSCy Schubert</td></tr>
287052d159aSCy Schubert<tr><td align="left" valign="top">&bull; <a href="#ntpd-Notes">ntpd Notes</a>:</td><td>&nbsp;&nbsp;</td><td align="left" valign="top">Notes
288052d159aSCy Schubert</td></tr>
289052d159aSCy Schubert</table>
2902b15cb3dSCy Schubert
291052d159aSCy Schubert<hr>
292052d159aSCy Schubert<a name="ntpd-usage"></a>
293052d159aSCy Schubert<div class="header">
294052d159aSCy Schubert<p>
295052d159aSCy SchubertNext: <a href="#ntpd-ipv4" accesskey="n" rel="next">ntpd ipv4</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> &nbsp; </p>
2962b15cb3dSCy Schubert</div>
297052d159aSCy Schubert<a name="ntpd-help_002fusage-_0028_002d_002dhelp_0029"></a>
298052d159aSCy Schubert<h4 class="subsection">1.1.1 ntpd help/usage (<samp>--help</samp>)</h4>
299052d159aSCy Schubert<a name="index-ntpd-help"></a>
3002b15cb3dSCy Schubert
301052d159aSCy Schubert<p>This is the automatically generated usage text for ntpd.
302052d159aSCy Schubert</p>
3032b15cb3dSCy Schubert<p>The text printed is the same whether selected with the <code>help</code> option
304052d159aSCy Schubert(<samp>--help</samp>) or the <code>more-help</code> option (<samp>--more-help</samp>).  <code>more-help</code> will print
3052b15cb3dSCy Schubertthe usage text by passing it through a pager program.
3062b15cb3dSCy Schubert<code>more-help</code> is disabled on platforms without a working
3072b15cb3dSCy Schubert<code>fork(2)</code> function.  The <code>PAGER</code> environment variable is
308052d159aSCy Schubertused to select the program, defaulting to <samp>more</samp>.  Both will exit
3092b15cb3dSCy Schubertwith a status code of 0.
310052d159aSCy Schubert</p>
311052d159aSCy Schubert<div class="example">
312*2d4e511cSCy Schubert<pre class="example">ntpd - NTP daemon program - Ver. 4.2.8p14
3132b15cb3dSCy SchubertUsage:  ntpd [ -&lt;flag&gt; [&lt;val&gt;] | --&lt;name&gt;[{=| }&lt;val&gt;] ]... \
3142b15cb3dSCy Schubert                [ &lt;server1&gt; ... &lt;serverN&gt; ]
3152b15cb3dSCy Schubert  Flg Arg Option-Name    Description
3162b15cb3dSCy Schubert   -4 no  ipv4           Force IPv4 DNS name resolution
3172b15cb3dSCy Schubert                                - prohibits the option 'ipv6'
3182b15cb3dSCy Schubert   -6 no  ipv6           Force IPv6 DNS name resolution
3192b15cb3dSCy Schubert                                - prohibits the option 'ipv4'
3202b15cb3dSCy Schubert   -a no  authreq        Require crypto authentication
3212b15cb3dSCy Schubert                                - prohibits the option 'authnoreq'
3222b15cb3dSCy Schubert   -A no  authnoreq      Do not require crypto authentication
3232b15cb3dSCy Schubert                                - prohibits the option 'authreq'
3242b15cb3dSCy Schubert   -b no  bcastsync      Allow us to sync to broadcast servers
3252b15cb3dSCy Schubert   -c Str configfile     configuration file name
3262b15cb3dSCy Schubert   -d no  debug-level    Increase debug verbosity level
3272b15cb3dSCy Schubert                                - may appear multiple times
3282b15cb3dSCy Schubert   -D Num set-debug-level Set the debug verbosity level
3292b15cb3dSCy Schubert                                - may appear multiple times
3302b15cb3dSCy Schubert   -f Str driftfile      frequency drift file name
3312b15cb3dSCy Schubert   -g no  panicgate      Allow the first adjustment to be Big
3322b15cb3dSCy Schubert                                - may appear multiple times
333a25439b6SCy Schubert   -G no  force-step-once Step any initial offset correction.
334*2d4e511cSCy Schubert   -i --- jaildir        built without --enable-clockctl or --enable-linuxcaps or --enable-solarisprivs
3352b15cb3dSCy Schubert   -I Str interface      Listen on an interface name or address
3362b15cb3dSCy Schubert                                - may appear multiple times
3372b15cb3dSCy Schubert   -k Str keyfile        path to symmetric keys
3382b15cb3dSCy Schubert   -l Str logfile        path to the log file
3392b15cb3dSCy Schubert   -L no  novirtualips   Do not listen to virtual interfaces
3402b15cb3dSCy Schubert   -n no  nofork         Do not fork
3412b15cb3dSCy Schubert                                - prohibits the option 'wait-sync'
3422b15cb3dSCy Schubert   -N no  nice           Run at high priority
3432b15cb3dSCy Schubert   -p Str pidfile        path to the PID file
3442b15cb3dSCy Schubert   -P Num priority       Process priority
3452b15cb3dSCy Schubert   -q no  quit           Set the time and quit
3462b15cb3dSCy Schubert                                - prohibits these options:
3472b15cb3dSCy Schubert                                saveconfigquit
3482b15cb3dSCy Schubert                                wait-sync
3492b15cb3dSCy Schubert   -r Str propagationdelay Broadcast/propagation delay
3502b15cb3dSCy Schubert      Str saveconfigquit Save parsed configuration and quit
3512b15cb3dSCy Schubert                                - prohibits these options:
3522b15cb3dSCy Schubert                                quit
3532b15cb3dSCy Schubert                                wait-sync
3542b15cb3dSCy Schubert   -s Str statsdir       Statistics file location
3552b15cb3dSCy Schubert   -t Str trustedkey     Trusted key number
3562b15cb3dSCy Schubert                                - may appear multiple times
357*2d4e511cSCy Schubert   -u --- user           built without --enable-clockctl or --enable-linuxcaps or --enable-solarisprivs
3582b15cb3dSCy Schubert   -U Num updateinterval interval in seconds between scans for new or dropped interfaces
3592b15cb3dSCy Schubert      Str var            make ARG an ntp variable (RW)
3602b15cb3dSCy Schubert                                - may appear multiple times
3612b15cb3dSCy Schubert      Str dvar           make ARG an ntp variable (RW|DEF)
3622b15cb3dSCy Schubert                                - may appear multiple times
3632b15cb3dSCy Schubert   -w Num wait-sync      Seconds to wait for first clock sync
3642b15cb3dSCy Schubert                                - prohibits these options:
3652b15cb3dSCy Schubert                                nofork
3662b15cb3dSCy Schubert                                quit
3672b15cb3dSCy Schubert                                saveconfigquit
3682b15cb3dSCy Schubert   -x no  slew           Slew up to 600 seconds
3692b15cb3dSCy Schubert      opt version        output version information and exit
3702b15cb3dSCy Schubert   -? no  help           display extended usage information and exit
3712b15cb3dSCy Schubert   -! no  more-help      extended usage information passed thru pager
3722b15cb3dSCy Schubert
3732b15cb3dSCy SchubertOptions are specified by doubled hyphens and their name or by a single
3742b15cb3dSCy Schuberthyphen and the flag character.
3752b15cb3dSCy Schubert
3762b15cb3dSCy Schubert
3772b15cb3dSCy SchubertThe following option preset mechanisms are supported:
3782b15cb3dSCy Schubert - examining environment variables named NTPD_*
3792b15cb3dSCy Schubert
3802b15cb3dSCy SchubertPlease send bug reports to:  &lt;http://bugs.ntp.org, bugs@ntp.org&gt;
381052d159aSCy Schubert</pre></div>
382052d159aSCy Schubert
383052d159aSCy Schubert<hr>
384052d159aSCy Schubert<a name="ntpd-ipv4"></a>
385052d159aSCy Schubert<div class="header">
386052d159aSCy Schubert<p>
387052d159aSCy SchubertNext: <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> &nbsp; </p>
3882b15cb3dSCy Schubert</div>
389052d159aSCy Schubert<a name="ipv4-option-_0028_002d4_0029"></a>
390052d159aSCy Schubert<h4 class="subsection">1.1.2 ipv4 option (-4)</h4>
391052d159aSCy Schubert<a name="index-ntpd_002dipv4"></a>
3922b15cb3dSCy Schubert
393052d159aSCy Schubert<p>This is the &ldquo;force ipv4 dns name resolution&rdquo; option.
394052d159aSCy Schubert</p>
395052d159aSCy Schubert<p>This option has some usage constraints.  It:
396052d159aSCy Schubert</p><ul>
3972b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
3982b15cb3dSCy Schubertipv6.
399052d159aSCy Schubert</li></ul>
4002b15cb3dSCy Schubert
4012b15cb3dSCy Schubert<p>Force DNS resolution of following host names on the command line
4022b15cb3dSCy Schubertto the IPv4 namespace.
403052d159aSCy Schubert</p><hr>
404052d159aSCy Schubert<a name="ntpd-ipv6"></a>
405052d159aSCy Schubert<div class="header">
406052d159aSCy Schubert<p>
407052d159aSCy SchubertNext: <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> &nbsp; </p>
4082b15cb3dSCy Schubert</div>
409052d159aSCy Schubert<a name="ipv6-option-_0028_002d6_0029"></a>
410052d159aSCy Schubert<h4 class="subsection">1.1.3 ipv6 option (-6)</h4>
411052d159aSCy Schubert<a name="index-ntpd_002dipv6"></a>
4122b15cb3dSCy Schubert
413052d159aSCy Schubert<p>This is the &ldquo;force ipv6 dns name resolution&rdquo; option.
414052d159aSCy Schubert</p>
415052d159aSCy Schubert<p>This option has some usage constraints.  It:
416052d159aSCy Schubert</p><ul>
4172b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
4182b15cb3dSCy Schubertipv4.
419052d159aSCy Schubert</li></ul>
4202b15cb3dSCy Schubert
4212b15cb3dSCy Schubert<p>Force DNS resolution of following host names on the command line
4222b15cb3dSCy Schubertto the IPv6 namespace.
423052d159aSCy Schubert</p><hr>
424052d159aSCy Schubert<a name="ntpd-authreq"></a>
425052d159aSCy Schubert<div class="header">
426052d159aSCy Schubert<p>
427052d159aSCy SchubertNext: <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> &nbsp; </p>
4282b15cb3dSCy Schubert</div>
429052d159aSCy Schubert<a name="authreq-option-_0028_002da_0029"></a>
430052d159aSCy Schubert<h4 class="subsection">1.1.4 authreq option (-a)</h4>
431052d159aSCy Schubert<a name="index-ntpd_002dauthreq"></a>
4322b15cb3dSCy Schubert
433052d159aSCy Schubert<p>This is the &ldquo;require crypto authentication&rdquo; option.
434052d159aSCy Schubert</p>
435052d159aSCy Schubert<p>This option has some usage constraints.  It:
436052d159aSCy Schubert</p><ul>
4372b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
4382b15cb3dSCy Schubertauthnoreq.
439052d159aSCy Schubert</li></ul>
4402b15cb3dSCy Schubert
4412b15cb3dSCy Schubert<p>Require cryptographic authentication for broadcast client,
4422b15cb3dSCy Schubertmulticast client and symmetric passive associations.
4432b15cb3dSCy SchubertThis is the default.
444052d159aSCy Schubert</p><hr>
445052d159aSCy Schubert<a name="ntpd-authnoreq"></a>
446052d159aSCy Schubert<div class="header">
447052d159aSCy Schubert<p>
448052d159aSCy SchubertNext: <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> &nbsp; </p>
4492b15cb3dSCy Schubert</div>
450052d159aSCy Schubert<a name="authnoreq-option-_0028_002dA_0029"></a>
451052d159aSCy Schubert<h4 class="subsection">1.1.5 authnoreq option (-A)</h4>
452052d159aSCy Schubert<a name="index-ntpd_002dauthnoreq"></a>
4532b15cb3dSCy Schubert
454052d159aSCy Schubert<p>This is the &ldquo;do not require crypto authentication&rdquo; option.
455052d159aSCy Schubert</p>
456052d159aSCy Schubert<p>This option has some usage constraints.  It:
457052d159aSCy Schubert</p><ul>
4582b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
4592b15cb3dSCy Schubertauthreq.
460052d159aSCy Schubert</li></ul>
4612b15cb3dSCy Schubert
4622b15cb3dSCy Schubert<p>Do not require cryptographic authentication for broadcast client,
4632b15cb3dSCy Schubertmulticast client and symmetric passive associations.
4642b15cb3dSCy SchubertThis is almost never a good idea.
465052d159aSCy Schubert</p><hr>
466052d159aSCy Schubert<a name="ntpd-configfile"></a>
467052d159aSCy Schubert<div class="header">
468052d159aSCy Schubert<p>
469052d159aSCy SchubertNext: <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> &nbsp; </p>
4702b15cb3dSCy Schubert</div>
471052d159aSCy Schubert<a name="configfile-option-_0028_002dc_0029"></a>
472052d159aSCy Schubert<h4 class="subsection">1.1.6 configfile option (-c)</h4>
473052d159aSCy Schubert<a name="index-ntpd_002dconfigfile"></a>
4742b15cb3dSCy Schubert
475052d159aSCy Schubert<p>This is the &ldquo;configuration file name&rdquo; option.
4762b15cb3dSCy SchubertThis option takes a string argument.
4772b15cb3dSCy SchubertThe name and path of the configuration file,
478052d159aSCy Schubert<samp>/etc/ntp.conf</samp>
4792b15cb3dSCy Schubertby default.
480052d159aSCy Schubert</p><hr>
481052d159aSCy Schubert<a name="ntpd-driftfile"></a>
482052d159aSCy Schubert<div class="header">
483052d159aSCy Schubert<p>
484052d159aSCy SchubertNext: <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> &nbsp; </p>
4852b15cb3dSCy Schubert</div>
486052d159aSCy Schubert<a name="driftfile-option-_0028_002df_0029"></a>
487052d159aSCy Schubert<h4 class="subsection">1.1.7 driftfile option (-f)</h4>
488052d159aSCy Schubert<a name="index-ntpd_002ddriftfile"></a>
4892b15cb3dSCy Schubert
490052d159aSCy Schubert<p>This is the &ldquo;frequency drift file name&rdquo; option.
4912b15cb3dSCy SchubertThis option takes a string argument.
4922b15cb3dSCy SchubertThe name and path of the frequency file,
493052d159aSCy Schubert<samp>/etc/ntp.drift</samp>
4942b15cb3dSCy Schubertby default.
4952b15cb3dSCy SchubertThis is the same operation as the
4962b15cb3dSCy Schubert<code>driftfile</code> <kbd>driftfile</kbd>
4972b15cb3dSCy Schubertconfiguration specification in the
498052d159aSCy Schubert<samp>/etc/ntp.conf</samp>
4992b15cb3dSCy Schubertfile.
500052d159aSCy Schubert</p><hr>
501052d159aSCy Schubert<a name="ntpd-panicgate"></a>
502052d159aSCy Schubert<div class="header">
503052d159aSCy Schubert<p>
504052d159aSCy SchubertNext: <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> &nbsp; </p>
5052b15cb3dSCy Schubert</div>
506052d159aSCy Schubert<a name="panicgate-option-_0028_002dg_0029"></a>
507052d159aSCy Schubert<h4 class="subsection">1.1.8 panicgate option (-g)</h4>
508052d159aSCy Schubert<a name="index-ntpd_002dpanicgate"></a>
5092b15cb3dSCy Schubert
510052d159aSCy Schubert<p>This is the &ldquo;allow the first adjustment to be big&rdquo; option.
511052d159aSCy Schubert</p>
512052d159aSCy Schubert<p>This option has some usage constraints.  It:
513052d159aSCy Schubert</p><ul>
5142b15cb3dSCy Schubert<li> may appear an unlimited number of times.
515052d159aSCy Schubert</li></ul>
5162b15cb3dSCy Schubert
5172b15cb3dSCy Schubert<p>Normally,
5182b15cb3dSCy Schubert<code>ntpd</code>
5192b15cb3dSCy Schubertexits 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,
5202b15cb3dSCy Schubert<code>ntpd</code>
5212b15cb3dSCy Schubertwill exit with a message to the system log. This option can be used with the
5222b15cb3dSCy Schubert<code>-q</code>
5232b15cb3dSCy Schubertand
5242b15cb3dSCy Schubert<code>-x</code>
5252b15cb3dSCy Schubertoptions.
5262b15cb3dSCy SchubertSee the
5272b15cb3dSCy Schubert<code>tinker</code>
5282b15cb3dSCy Schubertconfiguration file directive for other options.
529052d159aSCy Schubert</p><hr>
530052d159aSCy Schubert<a name="ntpd-force_002dstep_002donce"></a>
531052d159aSCy Schubert<div class="header">
532052d159aSCy Schubert<p>
533052d159aSCy SchubertNext: <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> &nbsp; </p>
5342b15cb3dSCy Schubert</div>
535052d159aSCy Schubert<a name="force_002dstep_002donce-option-_0028_002dG_0029"></a>
536052d159aSCy Schubert<h4 class="subsection">1.1.9 force-step-once option (-G)</h4>
537052d159aSCy Schubert<a name="index-ntpd_002dforce_002dstep_002donce"></a>
5382b15cb3dSCy Schubert
539052d159aSCy Schubert<p>This is the &ldquo;step any initial offset correction.&rdquo; option.
540a25439b6SCy SchubertNormally,
541a25439b6SCy Schubert<code>ntpd</code>
542a25439b6SCy Schubertsteps the time if the time offset exceeds the step threshold,
543a25439b6SCy Schubertwhich is 128 ms by default, and otherwise slews the time.
544a25439b6SCy SchubertThis option forces the initial offset correction to be stepped,
545a25439b6SCy Schubertso the highest time accuracy can be achieved quickly.
546a25439b6SCy SchubertHowever, this may also cause the time to be stepped back
547a25439b6SCy Schubertso this option must not be used if
548a25439b6SCy Schubertapplications requiring monotonic time are running.
549a25439b6SCy SchubertSee the <code>tinker</code> configuration file directive for other options.
550052d159aSCy Schubert</p><hr>
551052d159aSCy Schubert<a name="ntpd-jaildir"></a>
552052d159aSCy Schubert<div class="header">
553052d159aSCy Schubert<p>
554052d159aSCy SchubertNext: <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> &nbsp; </p>
555a25439b6SCy Schubert</div>
556052d159aSCy Schubert<a name="jaildir-option-_0028_002di_0029"></a>
557052d159aSCy Schubert<h4 class="subsection">1.1.10 jaildir option (-i)</h4>
558052d159aSCy Schubert<a name="index-ntpd_002djaildir"></a>
559a25439b6SCy Schubert
560052d159aSCy Schubert<p>This is the &ldquo;jail directory&rdquo; option.
5612b15cb3dSCy SchubertThis option takes a string argument.
562052d159aSCy Schubert</p>
563052d159aSCy Schubert<p>This option has some usage constraints.  It:
564052d159aSCy Schubert</p><ul>
5652b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
566052d159aSCy Schubert</li></ul>
5672b15cb3dSCy Schubert
5682b15cb3dSCy Schubert<p>Chroot the server to the directory
5692b15cb3dSCy Schubert<kbd>jaildir</kbd>
5702b15cb3dSCy Schubert.
5712b15cb3dSCy SchubertThis option also implies that the server attempts to drop root privileges at startup.
5722b15cb3dSCy SchubertYou may need to also specify a
5732b15cb3dSCy Schubert<code>-u</code>
5742b15cb3dSCy Schubertoption.
5752b15cb3dSCy SchubertThis option is only available if the OS supports adjusting the clock
5762b15cb3dSCy Schubertwithout full root privileges.
5772b15cb3dSCy SchubertThis option is supported under NetBSD (configure with
5782b15cb3dSCy Schubert<code>--enable-clockctl</code>) or Linux (configure with
5792b15cb3dSCy Schubert<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
580052d159aSCy Schubert</p><hr>
581052d159aSCy Schubert<a name="ntpd-interface"></a>
582052d159aSCy Schubert<div class="header">
583052d159aSCy Schubert<p>
584052d159aSCy SchubertNext: <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> &nbsp; </p>
5852b15cb3dSCy Schubert</div>
586052d159aSCy Schubert<a name="interface-option-_0028_002dI_0029"></a>
587052d159aSCy Schubert<h4 class="subsection">1.1.11 interface option (-I)</h4>
588052d159aSCy Schubert<a name="index-ntpd_002dinterface"></a>
5892b15cb3dSCy Schubert
590052d159aSCy Schubert<p>This is the &ldquo;listen on an interface name or address&rdquo; option.
591052d159aSCy SchubertThis option takes a string argument <samp>iface</samp>.
592052d159aSCy Schubert</p>
593052d159aSCy Schubert<p>This option has some usage constraints.  It:
594052d159aSCy Schubert</p><ul>
5952b15cb3dSCy Schubert<li> may appear an unlimited number of times.
596052d159aSCy Schubert</li></ul>
5972b15cb3dSCy Schubert
5982b15cb3dSCy Schubert<p>Open the network address given, or all the addresses associated with the
5992b15cb3dSCy Schubertgiven interface name.  This option may appear multiple times.  This option
6002b15cb3dSCy Schubertalso implies not opening other addresses, except wildcard and localhost.
6012b15cb3dSCy SchubertThis option is deprecated. Please consider using the configuration file
6022b15cb3dSCy Schubert<code>interface</code> command, which is more versatile.
603052d159aSCy Schubert</p><hr>
604052d159aSCy Schubert<a name="ntpd-keyfile"></a>
605052d159aSCy Schubert<div class="header">
606052d159aSCy Schubert<p>
607052d159aSCy SchubertNext: <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> &nbsp; </p>
6082b15cb3dSCy Schubert</div>
609052d159aSCy Schubert<a name="keyfile-option-_0028_002dk_0029"></a>
610052d159aSCy Schubert<h4 class="subsection">1.1.12 keyfile option (-k)</h4>
611052d159aSCy Schubert<a name="index-ntpd_002dkeyfile"></a>
6122b15cb3dSCy Schubert
613052d159aSCy Schubert<p>This is the &ldquo;path to symmetric keys&rdquo; option.
6142b15cb3dSCy SchubertThis option takes a string argument.
6152b15cb3dSCy SchubertSpecify the name and path of the symmetric key file.
616052d159aSCy Schubert<samp>/etc/ntp.keys</samp>
6172b15cb3dSCy Schubertis the default.
6182b15cb3dSCy SchubertThis is the same operation as the
6192b15cb3dSCy Schubert<code>keys</code> <kbd>keyfile</kbd>
6202b15cb3dSCy Schubertconfiguration file directive.
621052d159aSCy Schubert</p><hr>
622052d159aSCy Schubert<a name="ntpd-logfile"></a>
623052d159aSCy Schubert<div class="header">
624052d159aSCy Schubert<p>
625052d159aSCy SchubertNext: <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> &nbsp; </p>
6262b15cb3dSCy Schubert</div>
627052d159aSCy Schubert<a name="logfile-option-_0028_002dl_0029"></a>
628052d159aSCy Schubert<h4 class="subsection">1.1.13 logfile option (-l)</h4>
629052d159aSCy Schubert<a name="index-ntpd_002dlogfile"></a>
6302b15cb3dSCy Schubert
631052d159aSCy Schubert<p>This is the &ldquo;path to the log file&rdquo; option.
6322b15cb3dSCy SchubertThis option takes a string argument.
6332b15cb3dSCy SchubertSpecify the name and path of the log file.
6342b15cb3dSCy SchubertThe default is the system log file.
6352b15cb3dSCy SchubertThis is the same operation as the
6362b15cb3dSCy Schubert<code>logfile</code> <kbd>logfile</kbd>
6372b15cb3dSCy Schubertconfiguration file directive.
638052d159aSCy Schubert</p><hr>
639052d159aSCy Schubert<a name="ntpd-novirtualips"></a>
640052d159aSCy Schubert<div class="header">
641052d159aSCy Schubert<p>
642052d159aSCy SchubertNext: <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> &nbsp; </p>
6432b15cb3dSCy Schubert</div>
644052d159aSCy Schubert<a name="novirtualips-option-_0028_002dL_0029"></a>
645052d159aSCy Schubert<h4 class="subsection">1.1.14 novirtualips option (-L)</h4>
646052d159aSCy Schubert<a name="index-ntpd_002dnovirtualips"></a>
6472b15cb3dSCy Schubert
648052d159aSCy Schubert<p>This is the &ldquo;do not listen to virtual interfaces&rdquo; option.
6492b15cb3dSCy SchubertDo not listen to virtual interfaces, defined as those with
6502b15cb3dSCy Schubertnames containing a colon.  This option is deprecated.  Please
6512b15cb3dSCy Schubertconsider using the configuration file <code>interface</code> command, which
6522b15cb3dSCy Schubertis more versatile.
653052d159aSCy Schubert</p><hr>
654052d159aSCy Schubert<a name="ntpd-modifymmtimer"></a>
655052d159aSCy Schubert<div class="header">
656052d159aSCy Schubert<p>
657052d159aSCy SchubertNext: <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> &nbsp; </p>
6582b15cb3dSCy Schubert</div>
659052d159aSCy Schubert<a name="modifymmtimer-option-_0028_002dM_0029"></a>
660052d159aSCy Schubert<h4 class="subsection">1.1.15 modifymmtimer option (-M)</h4>
661052d159aSCy Schubert<a name="index-ntpd_002dmodifymmtimer"></a>
6622b15cb3dSCy Schubert
663052d159aSCy Schubert<p>This is the &ldquo;modify multimedia timer (windows only)&rdquo; option.
664052d159aSCy Schubert</p>
665052d159aSCy Schubert<p>This option has some usage constraints.  It:
666052d159aSCy Schubert</p><ul>
6672b15cb3dSCy Schubert<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
668052d159aSCy Schubert</li></ul>
6692b15cb3dSCy Schubert
6702b15cb3dSCy Schubert<p>Set the Windows Multimedia Timer to highest resolution.  This
6712b15cb3dSCy Schubertensures the resolution does not change while ntpd is running,
6722b15cb3dSCy Schubertavoiding timekeeping glitches associated with changes.
673052d159aSCy Schubert</p><hr>
674052d159aSCy Schubert<a name="ntpd-nice"></a>
675052d159aSCy Schubert<div class="header">
676052d159aSCy Schubert<p>
677052d159aSCy SchubertNext: <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> &nbsp; </p>
6782b15cb3dSCy Schubert</div>
679052d159aSCy Schubert<a name="nice-option-_0028_002dN_0029"></a>
680052d159aSCy Schubert<h4 class="subsection">1.1.16 nice option (-N)</h4>
681052d159aSCy Schubert<a name="index-ntpd_002dnice"></a>
6822b15cb3dSCy Schubert
683052d159aSCy Schubert<p>This is the &ldquo;run at high priority&rdquo; option.
6842b15cb3dSCy SchubertTo the extent permitted by the operating system, run
6852b15cb3dSCy Schubert<code>ntpd</code>
6862b15cb3dSCy Schubertat the highest priority.
687052d159aSCy Schubert</p><hr>
688052d159aSCy Schubert<a name="ntpd-pidfile"></a>
689052d159aSCy Schubert<div class="header">
690052d159aSCy Schubert<p>
691052d159aSCy SchubertNext: <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> &nbsp; </p>
6922b15cb3dSCy Schubert</div>
693052d159aSCy Schubert<a name="pidfile-option-_0028_002dp_0029"></a>
694052d159aSCy Schubert<h4 class="subsection">1.1.17 pidfile option (-p)</h4>
695052d159aSCy Schubert<a name="index-ntpd_002dpidfile"></a>
6962b15cb3dSCy Schubert
697052d159aSCy Schubert<p>This is the &ldquo;path to the pid file&rdquo; option.
6982b15cb3dSCy SchubertThis option takes a string argument.
6992b15cb3dSCy SchubertSpecify the name and path of the file used to record
700052d159aSCy Schubert<code>ntpd</code>&rsquo;s
7012b15cb3dSCy Schubertprocess ID.
7022b15cb3dSCy SchubertThis is the same operation as the
7032b15cb3dSCy Schubert<code>pidfile</code> <kbd>pidfile</kbd>
7042b15cb3dSCy Schubertconfiguration file directive.
705052d159aSCy Schubert</p><hr>
706052d159aSCy Schubert<a name="ntpd-priority"></a>
707052d159aSCy Schubert<div class="header">
708052d159aSCy Schubert<p>
709052d159aSCy SchubertNext: <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> &nbsp; </p>
7102b15cb3dSCy Schubert</div>
711052d159aSCy Schubert<a name="priority-option-_0028_002dP_0029"></a>
712052d159aSCy Schubert<h4 class="subsection">1.1.18 priority option (-P)</h4>
713052d159aSCy Schubert<a name="index-ntpd_002dpriority"></a>
7142b15cb3dSCy Schubert
715052d159aSCy Schubert<p>This is the &ldquo;process priority&rdquo; option.
7162b15cb3dSCy SchubertThis option takes a number argument.
7172b15cb3dSCy SchubertTo the extent permitted by the operating system, run
7182b15cb3dSCy Schubert<code>ntpd</code>
7192b15cb3dSCy Schubertat the specified
7202b15cb3dSCy Schubert<code>sched_setscheduler(SCHED_FIFO)</code>
7212b15cb3dSCy Schubertpriority.
722052d159aSCy Schubert</p><hr>
723052d159aSCy Schubert<a name="ntpd-quit"></a>
724052d159aSCy Schubert<div class="header">
725052d159aSCy Schubert<p>
726052d159aSCy SchubertNext: <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> &nbsp; </p>
7272b15cb3dSCy Schubert</div>
728052d159aSCy Schubert<a name="quit-option-_0028_002dq_0029"></a>
729052d159aSCy Schubert<h4 class="subsection">1.1.19 quit option (-q)</h4>
730052d159aSCy Schubert<a name="index-ntpd_002dquit"></a>
7312b15cb3dSCy Schubert
732052d159aSCy Schubert<p>This is the &ldquo;set the time and quit&rdquo; option.
733052d159aSCy Schubert</p>
734052d159aSCy Schubert<p>This option has some usage constraints.  It:
735052d159aSCy Schubert</p><ul>
7362b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
7372b15cb3dSCy Schubertsaveconfigquit, wait-sync.
738052d159aSCy Schubert</li></ul>
7392b15cb3dSCy Schubert
7402b15cb3dSCy Schubert<p><code>ntpd</code>
7412b15cb3dSCy Schubertwill not daemonize and will exit after the clock is first
7422b15cb3dSCy Schubertsynchronized.  This behavior mimics that of the
7432b15cb3dSCy Schubert<code>ntpdate</code>
7442b15cb3dSCy Schubertprogram, which will soon be replaced with a shell script.
7452b15cb3dSCy SchubertThe
7462b15cb3dSCy Schubert<code>-g</code>
7472b15cb3dSCy Schubertand
7482b15cb3dSCy Schubert<code>-x</code>
7492b15cb3dSCy Schubertoptions can be used with this option.
7502b15cb3dSCy SchubertNote: The kernel time discipline is disabled with this option.
751052d159aSCy Schubert</p><hr>
752052d159aSCy Schubert<a name="ntpd-propagationdelay"></a>
753052d159aSCy Schubert<div class="header">
754052d159aSCy Schubert<p>
755052d159aSCy SchubertNext: <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> &nbsp; </p>
7562b15cb3dSCy Schubert</div>
757052d159aSCy Schubert<a name="propagationdelay-option-_0028_002dr_0029"></a>
758052d159aSCy Schubert<h4 class="subsection">1.1.20 propagationdelay option (-r)</h4>
759052d159aSCy Schubert<a name="index-ntpd_002dpropagationdelay"></a>
7602b15cb3dSCy Schubert
761052d159aSCy Schubert<p>This is the &ldquo;broadcast/propagation delay&rdquo; option.
7622b15cb3dSCy SchubertThis option takes a string argument.
7632b15cb3dSCy SchubertSpecify 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.
764052d159aSCy Schubert</p><hr>
765052d159aSCy Schubert<a name="ntpd-saveconfigquit"></a>
766052d159aSCy Schubert<div class="header">
767052d159aSCy Schubert<p>
768052d159aSCy SchubertNext: <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> &nbsp; </p>
7692b15cb3dSCy Schubert</div>
770052d159aSCy Schubert<a name="saveconfigquit-option"></a>
771052d159aSCy Schubert<h4 class="subsection">1.1.21 saveconfigquit option</h4>
772052d159aSCy Schubert<a name="index-ntpd_002dsaveconfigquit"></a>
7732b15cb3dSCy Schubert
774052d159aSCy Schubert<p>This is the &ldquo;save parsed configuration and quit&rdquo; option.
7752b15cb3dSCy SchubertThis option takes a string argument.
776052d159aSCy Schubert</p>
777052d159aSCy Schubert<p>This option has some usage constraints.  It:
778052d159aSCy Schubert</p><ul>
7792b15cb3dSCy Schubert<li> must be compiled in by defining <code>SAVECONFIG</code> during the compilation.
780052d159aSCy Schubert</li><li> must not appear in combination with any of the following options:
7812b15cb3dSCy Schubertquit, wait-sync.
782052d159aSCy Schubert</li></ul>
7832b15cb3dSCy Schubert
7842b15cb3dSCy Schubert<p>Cause <code>ntpd</code> to parse its startup configuration file and save an
7852b15cb3dSCy Schubertequivalent to the given filename and exit.  This option was
7862b15cb3dSCy Schubertdesigned for automated testing.
787052d159aSCy Schubert</p><hr>
788052d159aSCy Schubert<a name="ntpd-statsdir"></a>
789052d159aSCy Schubert<div class="header">
790052d159aSCy Schubert<p>
791052d159aSCy SchubertNext: <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> &nbsp; </p>
7922b15cb3dSCy Schubert</div>
793052d159aSCy Schubert<a name="statsdir-option-_0028_002ds_0029"></a>
794052d159aSCy Schubert<h4 class="subsection">1.1.22 statsdir option (-s)</h4>
795052d159aSCy Schubert<a name="index-ntpd_002dstatsdir"></a>
7962b15cb3dSCy Schubert
797052d159aSCy Schubert<p>This is the &ldquo;statistics file location&rdquo; option.
7982b15cb3dSCy SchubertThis option takes a string argument.
7992b15cb3dSCy SchubertSpecify the directory path for files created by the statistics facility.
8002b15cb3dSCy SchubertThis is the same operation as the
8012b15cb3dSCy Schubert<code>statsdir</code> <kbd>statsdir</kbd>
8022b15cb3dSCy Schubertconfiguration file directive.
803052d159aSCy Schubert</p><hr>
804052d159aSCy Schubert<a name="ntpd-trustedkey"></a>
805052d159aSCy Schubert<div class="header">
806052d159aSCy Schubert<p>
807052d159aSCy SchubertNext: <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> &nbsp; </p>
8082b15cb3dSCy Schubert</div>
809052d159aSCy Schubert<a name="trustedkey-option-_0028_002dt_0029"></a>
810052d159aSCy Schubert<h4 class="subsection">1.1.23 trustedkey option (-t)</h4>
811052d159aSCy Schubert<a name="index-ntpd_002dtrustedkey"></a>
8122b15cb3dSCy Schubert
813052d159aSCy Schubert<p>This is the &ldquo;trusted key number&rdquo; option.
814052d159aSCy SchubertThis option takes a string argument <samp>tkey</samp>.
815052d159aSCy Schubert</p>
816052d159aSCy Schubert<p>This option has some usage constraints.  It:
817052d159aSCy Schubert</p><ul>
8182b15cb3dSCy Schubert<li> may appear an unlimited number of times.
819052d159aSCy Schubert</li></ul>
8202b15cb3dSCy Schubert
8212b15cb3dSCy Schubert<p>Add the specified key number to the trusted key list.
822052d159aSCy Schubert</p><hr>
823052d159aSCy Schubert<a name="ntpd-user"></a>
824052d159aSCy Schubert<div class="header">
825052d159aSCy Schubert<p>
826052d159aSCy SchubertNext: <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> &nbsp; </p>
8272b15cb3dSCy Schubert</div>
828052d159aSCy Schubert<a name="user-option-_0028_002du_0029"></a>
829052d159aSCy Schubert<h4 class="subsection">1.1.24 user option (-u)</h4>
830052d159aSCy Schubert<a name="index-ntpd_002duser"></a>
8312b15cb3dSCy Schubert
832052d159aSCy Schubert<p>This is the &ldquo;run as userid (or userid:groupid)&rdquo; option.
8332b15cb3dSCy SchubertThis option takes a string argument.
834052d159aSCy Schubert</p>
835052d159aSCy Schubert<p>This option has some usage constraints.  It:
836052d159aSCy Schubert</p><ul>
8372b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
838052d159aSCy Schubert</li></ul>
8392b15cb3dSCy Schubert
8402b15cb3dSCy Schubert<p>Specify a user, and optionally a group, to switch to.
8412b15cb3dSCy SchubertThis option is only available if the OS supports adjusting the clock
8422b15cb3dSCy Schubertwithout full root privileges.
8432b15cb3dSCy SchubertThis option is supported under NetBSD (configure with
8442b15cb3dSCy Schubert<code>--enable-clockctl</code>) or Linux (configure with
8452b15cb3dSCy Schubert<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
846052d159aSCy Schubert</p><hr>
847052d159aSCy Schubert<a name="ntpd-updateinterval"></a>
848052d159aSCy Schubert<div class="header">
849052d159aSCy Schubert<p>
850052d159aSCy SchubertNext: <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> &nbsp; </p>
8512b15cb3dSCy Schubert</div>
852052d159aSCy Schubert<a name="updateinterval-option-_0028_002dU_0029"></a>
853052d159aSCy Schubert<h4 class="subsection">1.1.25 updateinterval option (-U)</h4>
854052d159aSCy Schubert<a name="index-ntpd_002dupdateinterval"></a>
8552b15cb3dSCy Schubert
856052d159aSCy Schubert<p>This is the &ldquo;interval in seconds between scans for new or dropped interfaces&rdquo; option.
8572b15cb3dSCy SchubertThis option takes a number argument.
8582b15cb3dSCy SchubertGive the time in seconds between two scans for new or dropped interfaces.
8592b15cb3dSCy SchubertFor systems with routing socket support the scans will be performed shortly after the interface change
8602b15cb3dSCy Schuberthas been detected by the system.
8612b15cb3dSCy SchubertUse 0 to disable scanning. 60 seconds is the minimum time between scans.
862052d159aSCy Schubert</p><hr>
863052d159aSCy Schubert<a name="ntpd-wait_002dsync"></a>
864052d159aSCy Schubert<div class="header">
865052d159aSCy Schubert<p>
866052d159aSCy SchubertNext: <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> &nbsp; </p>
8672b15cb3dSCy Schubert</div>
868052d159aSCy Schubert<a name="wait_002dsync-option-_0028_002dw_0029"></a>
869052d159aSCy Schubert<h4 class="subsection">1.1.26 wait-sync option (-w)</h4>
870052d159aSCy Schubert<a name="index-ntpd_002dwait_002dsync"></a>
8712b15cb3dSCy Schubert
872052d159aSCy Schubert<p>This is the &ldquo;seconds to wait for first clock sync&rdquo; option.
8732b15cb3dSCy SchubertThis option takes a number argument.
874052d159aSCy Schubert</p>
875052d159aSCy Schubert<p>This option has some usage constraints.  It:
876052d159aSCy Schubert</p><ul>
8772b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_WORKING_FORK</code> during the compilation.
878052d159aSCy Schubert</li><li> must not appear in combination with any of the following options:
8792b15cb3dSCy Schubertnofork, quit, saveconfigquit.
880052d159aSCy Schubert</li></ul>
8812b15cb3dSCy Schubert
882052d159aSCy Schubert<p>If greater than zero, alters <code>ntpd</code>&rsquo;s behavior when forking to
8832b15cb3dSCy Schubertdaemonize.  Instead of exiting with status 0 immediately after
8842b15cb3dSCy Schubertthe fork, the parent waits up to the specified number of
8852b15cb3dSCy Schubertseconds for the child to first synchronize the clock.  The exit
8862b15cb3dSCy Schubertstatus is zero (success) if the clock was synchronized,
8872b15cb3dSCy Schubertotherwise it is <code>ETIMEDOUT</code>.
8882b15cb3dSCy SchubertThis provides the option for a script starting <code>ntpd</code> to easily
8892b15cb3dSCy Schubertwait for the first set of the clock before proceeding.
890052d159aSCy Schubert</p><hr>
891052d159aSCy Schubert<a name="ntpd-slew"></a>
892052d159aSCy Schubert<div class="header">
893052d159aSCy Schubert<p>
894052d159aSCy SchubertNext: <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> &nbsp; </p>
8952b15cb3dSCy Schubert</div>
896052d159aSCy Schubert<a name="slew-option-_0028_002dx_0029"></a>
897052d159aSCy Schubert<h4 class="subsection">1.1.27 slew option (-x)</h4>
898052d159aSCy Schubert<a name="index-ntpd_002dslew"></a>
8992b15cb3dSCy Schubert
900052d159aSCy Schubert<p>This is the &ldquo;slew up to 600 seconds&rdquo; option.
9012b15cb3dSCy SchubertNormally, 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.
9022b15cb3dSCy SchubertThis option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually.
9032b15cb3dSCy SchubertNote: 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.
9042b15cb3dSCy SchubertThus, an adjustment as much as 600 s will take almost 14 days to complete.
9052b15cb3dSCy SchubertThis option can be used with the
9062b15cb3dSCy Schubert<code>-g</code>
9072b15cb3dSCy Schubertand
9082b15cb3dSCy Schubert<code>-q</code>
9092b15cb3dSCy Schubertoptions.
9102b15cb3dSCy SchubertSee the
9112b15cb3dSCy Schubert<code>tinker</code>
9122b15cb3dSCy Schubertconfiguration file directive for other options.
9132b15cb3dSCy SchubertNote: The kernel time discipline is disabled with this option.
914052d159aSCy Schubert</p><hr>
915052d159aSCy Schubert<a name="ntpd-usepcc"></a>
916052d159aSCy Schubert<div class="header">
917052d159aSCy Schubert<p>
918052d159aSCy SchubertNext: <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> &nbsp; </p>
9192b15cb3dSCy Schubert</div>
920052d159aSCy Schubert<a name="usepcc-option"></a>
921052d159aSCy Schubert<h4 class="subsection">1.1.28 usepcc option</h4>
922052d159aSCy Schubert<a name="index-ntpd_002dusepcc"></a>
9232b15cb3dSCy Schubert
924052d159aSCy Schubert<p>This is the &ldquo;use cpu cycle counter (windows only)&rdquo; option.
925052d159aSCy Schubert</p>
926052d159aSCy Schubert<p>This option has some usage constraints.  It:
927052d159aSCy Schubert</p><ul>
9282b15cb3dSCy Schubert<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
929052d159aSCy Schubert</li></ul>
9302b15cb3dSCy Schubert
9312b15cb3dSCy Schubert<p>Attempt to substitute the CPU counter for <code>QueryPerformanceCounter</code>.
9322b15cb3dSCy SchubertThe CPU counter and <code>QueryPerformanceCounter</code> are compared, and if
9332b15cb3dSCy Schubertthey have the same frequency, the CPU counter (RDTSC on x86) is
9342b15cb3dSCy Schubertused directly, saving the overhead of a system call.
935052d159aSCy Schubert</p><hr>
936052d159aSCy Schubert<a name="ntpd-pccfreq"></a>
937052d159aSCy Schubert<div class="header">
938052d159aSCy Schubert<p>
939052d159aSCy SchubertNext: <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> &nbsp; </p>
9402b15cb3dSCy Schubert</div>
941052d159aSCy Schubert<a name="pccfreq-option"></a>
942052d159aSCy Schubert<h4 class="subsection">1.1.29 pccfreq option</h4>
943052d159aSCy Schubert<a name="index-ntpd_002dpccfreq"></a>
9442b15cb3dSCy Schubert
945052d159aSCy Schubert<p>This is the &ldquo;force cpu cycle counter use (windows only)&rdquo; option.
9462b15cb3dSCy SchubertThis option takes a string argument.
947052d159aSCy Schubert</p>
948052d159aSCy Schubert<p>This option has some usage constraints.  It:
949052d159aSCy Schubert</p><ul>
9502b15cb3dSCy Schubert<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
951052d159aSCy Schubert</li></ul>
9522b15cb3dSCy Schubert
9532b15cb3dSCy Schubert<p>Force substitution the CPU counter for <code>QueryPerformanceCounter</code>.
9542b15cb3dSCy SchubertThe CPU counter (RDTSC on x86) is used unconditionally with the
9552b15cb3dSCy Schubertgiven frequency (in Hz).
956052d159aSCy Schubert</p><hr>
957052d159aSCy Schubert<a name="ntpd-mdns"></a>
958052d159aSCy Schubert<div class="header">
959052d159aSCy Schubert<p>
960052d159aSCy SchubertNext: <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> &nbsp; </p>
9612b15cb3dSCy Schubert</div>
962052d159aSCy Schubert<a name="mdns-option-_0028_002dm_0029"></a>
963052d159aSCy Schubert<h4 class="subsection">1.1.30 mdns option (-m)</h4>
964052d159aSCy Schubert<a name="index-ntpd_002dmdns"></a>
9652b15cb3dSCy Schubert
966052d159aSCy Schubert<p>This is the &ldquo;register with mdns as a ntp server&rdquo; option.
967052d159aSCy Schubert</p>
968052d159aSCy Schubert<p>This option has some usage constraints.  It:
969052d159aSCy Schubert</p><ul>
9702b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_DNSREGISTRATION</code> during the compilation.
971052d159aSCy Schubert</li></ul>
9722b15cb3dSCy Schubert
9732b15cb3dSCy Schubert<p>Registers as an NTP server with the local mDNS server which allows
9742b15cb3dSCy Schubertthe server to be discovered via mDNS client lookup.
975052d159aSCy Schubert</p>
9762b15cb3dSCy Schubert
977052d159aSCy Schubert<hr>
978052d159aSCy Schubert<a name="ntpd-config"></a>
979052d159aSCy Schubert<div class="header">
980052d159aSCy Schubert<p>
981052d159aSCy SchubertNext: <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> &nbsp; </p>
9822b15cb3dSCy Schubert</div>
983052d159aSCy Schubert<a name="presetting_002fconfiguring-ntpd"></a>
984052d159aSCy Schubert<h4 class="subsection">1.1.31 presetting/configuring ntpd</h4>
9852b15cb3dSCy Schubert
9862b15cb3dSCy Schubert<p>Any option that is not marked as <i>not presettable</i> may be preset by
9872b15cb3dSCy Schubertloading values from environment variables named <code>NTPD</code> and <code>NTPD_&lt;OPTION_NAME&gt;</code>.  <code>&lt;OPTION_NAME&gt;</code> must be one of
9882b15cb3dSCy Schubertthe options listed above in upper case and segmented with underscores.
9892b15cb3dSCy SchubertThe <code>NTPD</code> variable will be tokenized and parsed like
9902b15cb3dSCy Schubertthe command line.  The remaining variables are tested for existence and their
9912b15cb3dSCy Schubertvalues are treated like option arguments.
992052d159aSCy Schubert</p>
9932b15cb3dSCy Schubert
9942b15cb3dSCy Schubert<p>The command line options relating to configuration and/or usage help are:
995052d159aSCy Schubert</p>
996052d159aSCy Schubert<a name="version-_0028_002d_0029"></a>
997052d159aSCy Schubert<h4 class="subsubheading">version (-)</h4>
9982b15cb3dSCy Schubert
9992b15cb3dSCy Schubert<p>Print the program version to standard out, optionally with licensing
10002b15cb3dSCy Schubertinformation, then exit 0.  The optional argument specifies how much licensing
10012b15cb3dSCy Schubertdetail to provide.  The default is to print just the version.  The licensing infomation may be selected with an option argument.
10022b15cb3dSCy SchubertOnly the first letter of the argument is examined:
1003052d159aSCy Schubert</p>
1004052d159aSCy Schubert<dl compact="compact">
1005052d159aSCy Schubert<dt>&lsquo;<samp>version</samp>&rsquo;</dt>
1006052d159aSCy Schubert<dd><p>Only print the version.  This is the default.
1007052d159aSCy Schubert</p></dd>
1008052d159aSCy Schubert<dt>&lsquo;<samp>copyright</samp>&rsquo;</dt>
1009052d159aSCy Schubert<dd><p>Name the copyright usage licensing terms.
1010052d159aSCy Schubert</p></dd>
1011052d159aSCy Schubert<dt>&lsquo;<samp>verbose</samp>&rsquo;</dt>
1012052d159aSCy Schubert<dd><p>Print the full copyright usage licensing terms.
1013052d159aSCy Schubert</p></dd>
10142b15cb3dSCy Schubert</dl>
10152b15cb3dSCy Schubert
1016052d159aSCy Schubert<hr>
1017052d159aSCy Schubert<a name="ntpd-exit-status"></a>
1018052d159aSCy Schubert<div class="header">
1019052d159aSCy Schubert<p>
1020052d159aSCy SchubertNext: <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> &nbsp; </p>
10212b15cb3dSCy Schubert</div>
1022052d159aSCy Schubert<a name="ntpd-exit-status-1"></a>
1023052d159aSCy Schubert<h4 class="subsection">1.1.32 ntpd exit status</h4>
10242b15cb3dSCy Schubert
10252b15cb3dSCy Schubert<p>One of the following exit values will be returned:
1026052d159aSCy Schubert</p><dl compact="compact">
1027052d159aSCy Schubert<dt>&lsquo;<samp>0 (EXIT_SUCCESS)</samp>&rsquo;</dt>
1028052d159aSCy Schubert<dd><p>Successful program execution.
1029052d159aSCy Schubert</p></dd>
1030052d159aSCy Schubert<dt>&lsquo;<samp>1 (EXIT_FAILURE)</samp>&rsquo;</dt>
1031052d159aSCy Schubert<dd><p>The operation failed or the command syntax was not valid.
1032052d159aSCy Schubert</p></dd>
10332b15cb3dSCy Schubert</dl>
1034052d159aSCy Schubert<hr>
1035052d159aSCy Schubert<a name="ntpd-Usage"></a>
1036052d159aSCy Schubert<div class="header">
1037052d159aSCy Schubert<p>
1038052d159aSCy SchubertNext: <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> &nbsp; </p>
10392b15cb3dSCy Schubert</div>
1040052d159aSCy Schubert<a name="ntpd-Usage-1"></a>
1041052d159aSCy Schubert<h4 class="subsection">1.1.33 ntpd Usage</h4>
1042052d159aSCy Schubert<hr>
1043052d159aSCy Schubert<a name="ntpd-Files"></a>
1044052d159aSCy Schubert<div class="header">
1045052d159aSCy Schubert<p>
1046052d159aSCy SchubertNext: <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> &nbsp; </p>
10472b15cb3dSCy Schubert</div>
1048052d159aSCy Schubert<a name="ntpd-Files-1"></a>
1049052d159aSCy Schubert<h4 class="subsection">1.1.34 ntpd Files</h4>
1050052d159aSCy Schubert<hr>
1051052d159aSCy Schubert<a name="ntpd-See-Also"></a>
1052052d159aSCy Schubert<div class="header">
1053052d159aSCy Schubert<p>
1054052d159aSCy SchubertNext: <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> &nbsp; </p>
10552b15cb3dSCy Schubert</div>
1056052d159aSCy Schubert<a name="ntpd-See-Also-1"></a>
1057052d159aSCy Schubert<h4 class="subsection">1.1.35 ntpd See Also</h4>
1058052d159aSCy Schubert<hr>
1059052d159aSCy Schubert<a name="ntpd-Bugs"></a>
1060052d159aSCy Schubert<div class="header">
1061052d159aSCy Schubert<p>
1062052d159aSCy SchubertNext: <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> &nbsp; </p>
10632b15cb3dSCy Schubert</div>
1064052d159aSCy Schubert<a name="ntpd-Bugs-1"></a>
1065052d159aSCy Schubert<h4 class="subsection">1.1.36 ntpd Bugs</h4>
1066052d159aSCy Schubert<hr>
1067052d159aSCy Schubert<a name="ntpd-Notes"></a>
1068052d159aSCy Schubert<div class="header">
1069052d159aSCy Schubert<p>
1070052d159aSCy SchubertPrevious: <a href="#ntpd-Bugs" accesskey="p" rel="prev">ntpd Bugs</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> &nbsp; </p>
10712b15cb3dSCy Schubert</div>
1072052d159aSCy Schubert<a name="ntpd-Notes-1"></a>
1073052d159aSCy Schubert<h4 class="subsection">1.1.37 ntpd Notes</h4>
10742b15cb3dSCy Schubert
1075052d159aSCy Schubert<hr>
10762b15cb3dSCy Schubert<a name="Usage"></a>
1077052d159aSCy Schubert<div class="header">
1078052d159aSCy Schubert<p>
1079052d159aSCy SchubertPrevious: <a href="#ntpd-Invocation" accesskey="p" rel="prev">ntpd Invocation</a>, Up: <a href="#ntpd-Description" accesskey="u" rel="up">ntpd Description</a> &nbsp; </p>
10802b15cb3dSCy Schubert</div>
1081052d159aSCy Schubert<a name="Usage-1"></a>
1082052d159aSCy Schubert<h3 class="section">1.2 Usage</h3>
10832b15cb3dSCy Schubert
1084052d159aSCy Schubert<table>
1085052d159aSCy Schubert<thead><tr><th width="23%">What</th><th width="23%">Default</th><th width="5%">Flag</th><th width="15%">Option</th></tr></thead>
1086052d159aSCy Schubert<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>
1087052d159aSCy Schubert<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>
1088052d159aSCy Schubert<tr><td width="23%">leapseconds file</td><td width="23%">none</td><td width="5%"></td><td width="15%"><code>leapfile</code></td></tr>
1089052d159aSCy Schubert<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>
1090052d159aSCy Schubert<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>
1091052d159aSCy Schubert<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>
1092052d159aSCy Schubert<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>
1093052d159aSCy Schubert<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>
1094052d159aSCy Schubert</table>
1095052d159aSCy Schubert<hr>
10962b15cb3dSCy Schubert
1097052d159aSCy Schubert
1098052d159aSCy Schubert
1099052d159aSCy Schubert</body>
1100052d159aSCy Schubert</html>
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