xref: /freebsd/contrib/ntp/ntpd/ntpd.html (revision 052d159a8b83f03d7dc5eb31cd9a9b4a6fe3d9da)
1*052d159aSCy Schubert<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
2*052d159aSCy Schubert<html>
3*052d159aSCy Schubert<!-- Created by GNU Texinfo 6.5, http://www.gnu.org/software/texinfo/ -->
42b15cb3dSCy Schubert<head>
5*052d159aSCy Schubert<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
6*052d159aSCy Schubert<title>ntpd: Network Time Protocol (NTP) Daemon User&rsquo;s Manual</title>
7*052d159aSCy Schubert
8*052d159aSCy Schubert<meta name="description" content="ntpd: Network Time Protocol (NTP) Daemon User&rsquo;s Manual">
9*052d159aSCy Schubert<meta name="keywords" content="ntpd: Network Time Protocol (NTP) Daemon User&rsquo;s Manual">
10*052d159aSCy Schubert<meta name="resource-type" content="document">
11*052d159aSCy Schubert<meta name="distribution" content="global">
12*052d159aSCy Schubert<meta name="Generator" content="makeinfo">
13*052d159aSCy Schubert<link href="#Top" rel="start" title="Top">
14*052d159aSCy Schubert<link href="dir.html#Top" rel="up" title="(dir)">
15*052d159aSCy Schubert<style type="text/css">
16*052d159aSCy Schubert<!--
17*052d159aSCy Schuberta.summary-letter {text-decoration: none}
18*052d159aSCy Schubertblockquote.indentedblock {margin-right: 0em}
19*052d159aSCy Schubertblockquote.smallindentedblock {margin-right: 0em; font-size: smaller}
20*052d159aSCy Schubertblockquote.smallquotation {font-size: smaller}
21*052d159aSCy Schubertdiv.display {margin-left: 3.2em}
22*052d159aSCy Schubertdiv.example {margin-left: 3.2em}
23*052d159aSCy Schubertdiv.lisp {margin-left: 3.2em}
24*052d159aSCy Schubertdiv.smalldisplay {margin-left: 3.2em}
25*052d159aSCy Schubertdiv.smallexample {margin-left: 3.2em}
26*052d159aSCy Schubertdiv.smalllisp {margin-left: 3.2em}
27*052d159aSCy Schubertkbd {font-style: oblique}
282b15cb3dSCy Schubertpre.display {font-family: inherit}
292b15cb3dSCy Schubertpre.format {font-family: inherit}
30*052d159aSCy Schubertpre.menu-comment {font-family: serif}
31*052d159aSCy Schubertpre.menu-preformatted {font-family: serif}
322b15cb3dSCy Schubertpre.smalldisplay {font-family: inherit; font-size: smaller}
332b15cb3dSCy Schubertpre.smallexample {font-size: smaller}
34*052d159aSCy Schubertpre.smallformat {font-family: inherit; font-size: smaller}
352b15cb3dSCy Schubertpre.smalllisp {font-size: smaller}
36*052d159aSCy Schubertspan.nolinebreak {white-space: nowrap}
37*052d159aSCy Schubertspan.roman {font-family: initial; font-weight: normal}
38*052d159aSCy Schubertspan.sansserif {font-family: sans-serif; font-weight: normal}
39*052d159aSCy Schubertul.no-bullet {list-style: none}
40*052d159aSCy Schubert-->
41*052d159aSCy Schubert</style>
422b15cb3dSCy Schubert
43*052d159aSCy Schubert
44*052d159aSCy Schubert</head>
45*052d159aSCy Schubert
46*052d159aSCy Schubert<body lang="en">
47*052d159aSCy Schubert<h1 class="settitle" align="center">ntpd: Network Time Protocol (NTP) Daemon User&rsquo;s Manual</h1>
48*052d159aSCy Schubert
49*052d159aSCy Schubert
50*052d159aSCy Schubert
51*052d159aSCy Schubert
52*052d159aSCy Schubert
53*052d159aSCy Schubert<a name="Top"></a>
54*052d159aSCy Schubert<div class="header">
55*052d159aSCy Schubert<p>
56*052d159aSCy 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>
57*052d159aSCy Schubert</div>
58*052d159aSCy Schubert<a name="ntpd_003a-Network-Time-Protocol-_0028NTP_0029-Daemon-User-Manual"></a>
59*052d159aSCy 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.
69*052d159aSCy Schubert</p>
70*052d159aSCy Schubert<p>This document applies to version 4.2.8p13 of <code>ntpd</code>.
71*052d159aSCy Schubert</p>
72*052d159aSCy Schubert<a name="SEC_Overview"></a>
73*052d159aSCy Schubert<h2 class="shortcontents-heading">Short Table of Contents</h2>
742b15cb3dSCy Schubert
75*052d159aSCy Schubert<div class="shortcontents">
76*052d159aSCy Schubert<ul class="no-bullet">
77*052d159aSCy Schubert<li><a name="stoc-Description" href="#toc-Description">1 Description</a></li>
782b15cb3dSCy Schubert</ul>
792b15cb3dSCy Schubert</div>
802b15cb3dSCy Schubert
81*052d159aSCy Schubert
82*052d159aSCy Schubert<table class="menu" border="0" cellspacing="0">
83*052d159aSCy 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
84*052d159aSCy Schubert</td></tr>
85*052d159aSCy 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
86*052d159aSCy Schubert</td></tr>
87*052d159aSCy 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
88*052d159aSCy Schubert</td></tr>
89*052d159aSCy Schubert</table>
90*052d159aSCy Schubert
91*052d159aSCy Schubert<hr>
92*052d159aSCy Schubert<a name="ntpd-Description"></a>
93*052d159aSCy Schubert<div class="header">
94*052d159aSCy Schubert<p>
95*052d159aSCy SchubertNext: <a href="#ntpd-Invocation" accesskey="n" rel="next">ntpd Invocation</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> &nbsp; </p>
96*052d159aSCy Schubert</div>
97*052d159aSCy Schubert<a name="Description"></a>
98*052d159aSCy Schubert<h2 class="chapter">1 Description</h2>
992b15cb3dSCy Schubert
1002b15cb3dSCy Schubert<p>The <code>ntpd</code> program ordinarily requires
101*052d159aSCy 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.
108*052d159aSCy 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
117*052d159aSCy Schubertgroom the data and set the clock in about ten seconds&rsquo; time.
118*052d159aSCy SchubertIf nothing is heard after a few minutes&rsquo; time,
1192b15cb3dSCy Schubertthe daemon times out and exits without setting the clock.
120*052d159aSCy Schubert</p>
121*052d159aSCy Schubert<table class="menu" border="0" cellspacing="0">
122*052d159aSCy 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">
123*052d159aSCy Schubert</td></tr>
124*052d159aSCy 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">
125*052d159aSCy Schubert</td></tr>
126*052d159aSCy Schubert</table>
1272b15cb3dSCy Schubert
128*052d159aSCy Schubert<hr>
1292b15cb3dSCy Schubert<a name="ntpd-Invocation"></a>
130*052d159aSCy Schubert<div class="header">
131*052d159aSCy Schubert<p>
132*052d159aSCy 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>
134*052d159aSCy Schubert<a name="Invoking-ntpd"></a>
135*052d159aSCy Schubert<h3 class="section">1.1 Invoking ntpd</h3>
136*052d159aSCy Schubert<a name="index-ntpd"></a>
137*052d159aSCy 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.
151*052d159aSCy 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.
161*052d159aSCy 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.
175*052d159aSCy 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.
187*052d159aSCy 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.
199*052d159aSCy 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.
209*052d159aSCy 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;.
213*052d159aSCy Schubert</p>
214*052d159aSCy Schubert<table class="menu" border="0" cellspacing="0">
215*052d159aSCy 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>)
216*052d159aSCy Schubert</td></tr>
217*052d159aSCy 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)
218*052d159aSCy Schubert</td></tr>
219*052d159aSCy 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)
220*052d159aSCy Schubert</td></tr>
221*052d159aSCy 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)
222*052d159aSCy Schubert</td></tr>
223*052d159aSCy 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)
224*052d159aSCy Schubert</td></tr>
225*052d159aSCy 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)
226*052d159aSCy Schubert</td></tr>
227*052d159aSCy 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)
228*052d159aSCy Schubert</td></tr>
229*052d159aSCy 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)
230*052d159aSCy Schubert</td></tr>
231*052d159aSCy 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)
232*052d159aSCy Schubert</td></tr>
233*052d159aSCy 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)
234*052d159aSCy Schubert</td></tr>
235*052d159aSCy 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)
236*052d159aSCy Schubert</td></tr>
237*052d159aSCy 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)
238*052d159aSCy Schubert</td></tr>
239*052d159aSCy 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)
240*052d159aSCy Schubert</td></tr>
241*052d159aSCy 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)
242*052d159aSCy Schubert</td></tr>
243*052d159aSCy 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)
244*052d159aSCy Schubert</td></tr>
245*052d159aSCy 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)
246*052d159aSCy Schubert</td></tr>
247*052d159aSCy 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)
248*052d159aSCy Schubert</td></tr>
249*052d159aSCy 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)
250*052d159aSCy Schubert</td></tr>
251*052d159aSCy 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)
252*052d159aSCy Schubert</td></tr>
253*052d159aSCy 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)
254*052d159aSCy Schubert</td></tr>
255*052d159aSCy 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
256*052d159aSCy Schubert</td></tr>
257*052d159aSCy 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)
258*052d159aSCy Schubert</td></tr>
259*052d159aSCy 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)
260*052d159aSCy Schubert</td></tr>
261*052d159aSCy 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)
262*052d159aSCy Schubert</td></tr>
263*052d159aSCy 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)
264*052d159aSCy Schubert</td></tr>
265*052d159aSCy 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)
266*052d159aSCy Schubert</td></tr>
267*052d159aSCy 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)
268*052d159aSCy Schubert</td></tr>
269*052d159aSCy 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
270*052d159aSCy Schubert</td></tr>
271*052d159aSCy 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
272*052d159aSCy Schubert</td></tr>
273*052d159aSCy 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)
274*052d159aSCy Schubert</td></tr>
275*052d159aSCy 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
276*052d159aSCy Schubert</td></tr>
277*052d159aSCy 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
278*052d159aSCy Schubert</td></tr>
279*052d159aSCy 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
280*052d159aSCy Schubert</td></tr>
281*052d159aSCy 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
282*052d159aSCy Schubert</td></tr>
283*052d159aSCy 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
284*052d159aSCy Schubert</td></tr>
285*052d159aSCy 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
286*052d159aSCy Schubert</td></tr>
287*052d159aSCy 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
288*052d159aSCy Schubert</td></tr>
289*052d159aSCy Schubert</table>
2902b15cb3dSCy Schubert
291*052d159aSCy Schubert<hr>
292*052d159aSCy Schubert<a name="ntpd-usage"></a>
293*052d159aSCy Schubert<div class="header">
294*052d159aSCy Schubert<p>
295*052d159aSCy 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>
297*052d159aSCy Schubert<a name="ntpd-help_002fusage-_0028_002d_002dhelp_0029"></a>
298*052d159aSCy Schubert<h4 class="subsection">1.1.1 ntpd help/usage (<samp>--help</samp>)</h4>
299*052d159aSCy Schubert<a name="index-ntpd-help"></a>
3002b15cb3dSCy Schubert
301*052d159aSCy Schubert<p>This is the automatically generated usage text for ntpd.
302*052d159aSCy Schubert</p>
3032b15cb3dSCy Schubert<p>The text printed is the same whether selected with the <code>help</code> option
304*052d159aSCy 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
308*052d159aSCy Schubertused to select the program, defaulting to <samp>more</samp>.  Both will exit
3092b15cb3dSCy Schubertwith a status code of 0.
310*052d159aSCy Schubert</p>
311*052d159aSCy Schubert<div class="example">
312*052d159aSCy Schubert<pre class="example">ntpd - NTP daemon program - Ver. 4.2.8p12
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.
3342b15cb3dSCy Schubert   -i Str jaildir        Jail directory
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
3572b15cb3dSCy Schubert   -u Str user           Run as userid (or userid:groupid)
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;
381*052d159aSCy Schubert</pre></div>
382*052d159aSCy Schubert
383*052d159aSCy Schubert<hr>
384*052d159aSCy Schubert<a name="ntpd-ipv4"></a>
385*052d159aSCy Schubert<div class="header">
386*052d159aSCy Schubert<p>
387*052d159aSCy 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>
389*052d159aSCy Schubert<a name="ipv4-option-_0028_002d4_0029"></a>
390*052d159aSCy Schubert<h4 class="subsection">1.1.2 ipv4 option (-4)</h4>
391*052d159aSCy Schubert<a name="index-ntpd_002dipv4"></a>
3922b15cb3dSCy Schubert
393*052d159aSCy Schubert<p>This is the &ldquo;force ipv4 dns name resolution&rdquo; option.
394*052d159aSCy Schubert</p>
395*052d159aSCy Schubert<p>This option has some usage constraints.  It:
396*052d159aSCy Schubert</p><ul>
3972b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
3982b15cb3dSCy Schubertipv6.
399*052d159aSCy Schubert</li></ul>
4002b15cb3dSCy Schubert
4012b15cb3dSCy Schubert<p>Force DNS resolution of following host names on the command line
4022b15cb3dSCy Schubertto the IPv4 namespace.
403*052d159aSCy Schubert</p><hr>
404*052d159aSCy Schubert<a name="ntpd-ipv6"></a>
405*052d159aSCy Schubert<div class="header">
406*052d159aSCy Schubert<p>
407*052d159aSCy 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>
409*052d159aSCy Schubert<a name="ipv6-option-_0028_002d6_0029"></a>
410*052d159aSCy Schubert<h4 class="subsection">1.1.3 ipv6 option (-6)</h4>
411*052d159aSCy Schubert<a name="index-ntpd_002dipv6"></a>
4122b15cb3dSCy Schubert
413*052d159aSCy Schubert<p>This is the &ldquo;force ipv6 dns name resolution&rdquo; option.
414*052d159aSCy Schubert</p>
415*052d159aSCy Schubert<p>This option has some usage constraints.  It:
416*052d159aSCy Schubert</p><ul>
4172b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
4182b15cb3dSCy Schubertipv4.
419*052d159aSCy Schubert</li></ul>
4202b15cb3dSCy Schubert
4212b15cb3dSCy Schubert<p>Force DNS resolution of following host names on the command line
4222b15cb3dSCy Schubertto the IPv6 namespace.
423*052d159aSCy Schubert</p><hr>
424*052d159aSCy Schubert<a name="ntpd-authreq"></a>
425*052d159aSCy Schubert<div class="header">
426*052d159aSCy Schubert<p>
427*052d159aSCy 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>
429*052d159aSCy Schubert<a name="authreq-option-_0028_002da_0029"></a>
430*052d159aSCy Schubert<h4 class="subsection">1.1.4 authreq option (-a)</h4>
431*052d159aSCy Schubert<a name="index-ntpd_002dauthreq"></a>
4322b15cb3dSCy Schubert
433*052d159aSCy Schubert<p>This is the &ldquo;require crypto authentication&rdquo; option.
434*052d159aSCy Schubert</p>
435*052d159aSCy Schubert<p>This option has some usage constraints.  It:
436*052d159aSCy Schubert</p><ul>
4372b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
4382b15cb3dSCy Schubertauthnoreq.
439*052d159aSCy 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.
444*052d159aSCy Schubert</p><hr>
445*052d159aSCy Schubert<a name="ntpd-authnoreq"></a>
446*052d159aSCy Schubert<div class="header">
447*052d159aSCy Schubert<p>
448*052d159aSCy 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>
450*052d159aSCy Schubert<a name="authnoreq-option-_0028_002dA_0029"></a>
451*052d159aSCy Schubert<h4 class="subsection">1.1.5 authnoreq option (-A)</h4>
452*052d159aSCy Schubert<a name="index-ntpd_002dauthnoreq"></a>
4532b15cb3dSCy Schubert
454*052d159aSCy Schubert<p>This is the &ldquo;do not require crypto authentication&rdquo; option.
455*052d159aSCy Schubert</p>
456*052d159aSCy Schubert<p>This option has some usage constraints.  It:
457*052d159aSCy Schubert</p><ul>
4582b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
4592b15cb3dSCy Schubertauthreq.
460*052d159aSCy 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.
465*052d159aSCy Schubert</p><hr>
466*052d159aSCy Schubert<a name="ntpd-configfile"></a>
467*052d159aSCy Schubert<div class="header">
468*052d159aSCy Schubert<p>
469*052d159aSCy 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>
471*052d159aSCy Schubert<a name="configfile-option-_0028_002dc_0029"></a>
472*052d159aSCy Schubert<h4 class="subsection">1.1.6 configfile option (-c)</h4>
473*052d159aSCy Schubert<a name="index-ntpd_002dconfigfile"></a>
4742b15cb3dSCy Schubert
475*052d159aSCy 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,
478*052d159aSCy Schubert<samp>/etc/ntp.conf</samp>
4792b15cb3dSCy Schubertby default.
480*052d159aSCy Schubert</p><hr>
481*052d159aSCy Schubert<a name="ntpd-driftfile"></a>
482*052d159aSCy Schubert<div class="header">
483*052d159aSCy Schubert<p>
484*052d159aSCy 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>
486*052d159aSCy Schubert<a name="driftfile-option-_0028_002df_0029"></a>
487*052d159aSCy Schubert<h4 class="subsection">1.1.7 driftfile option (-f)</h4>
488*052d159aSCy Schubert<a name="index-ntpd_002ddriftfile"></a>
4892b15cb3dSCy Schubert
490*052d159aSCy 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,
493*052d159aSCy 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
498*052d159aSCy Schubert<samp>/etc/ntp.conf</samp>
4992b15cb3dSCy Schubertfile.
500*052d159aSCy Schubert</p><hr>
501*052d159aSCy Schubert<a name="ntpd-panicgate"></a>
502*052d159aSCy Schubert<div class="header">
503*052d159aSCy Schubert<p>
504*052d159aSCy 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>
506*052d159aSCy Schubert<a name="panicgate-option-_0028_002dg_0029"></a>
507*052d159aSCy Schubert<h4 class="subsection">1.1.8 panicgate option (-g)</h4>
508*052d159aSCy Schubert<a name="index-ntpd_002dpanicgate"></a>
5092b15cb3dSCy Schubert
510*052d159aSCy Schubert<p>This is the &ldquo;allow the first adjustment to be big&rdquo; option.
511*052d159aSCy Schubert</p>
512*052d159aSCy Schubert<p>This option has some usage constraints.  It:
513*052d159aSCy Schubert</p><ul>
5142b15cb3dSCy Schubert<li> may appear an unlimited number of times.
515*052d159aSCy 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.
529*052d159aSCy Schubert</p><hr>
530*052d159aSCy Schubert<a name="ntpd-force_002dstep_002donce"></a>
531*052d159aSCy Schubert<div class="header">
532*052d159aSCy Schubert<p>
533*052d159aSCy 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>
535*052d159aSCy Schubert<a name="force_002dstep_002donce-option-_0028_002dG_0029"></a>
536*052d159aSCy Schubert<h4 class="subsection">1.1.9 force-step-once option (-G)</h4>
537*052d159aSCy Schubert<a name="index-ntpd_002dforce_002dstep_002donce"></a>
5382b15cb3dSCy Schubert
539*052d159aSCy 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.
550*052d159aSCy Schubert</p><hr>
551*052d159aSCy Schubert<a name="ntpd-jaildir"></a>
552*052d159aSCy Schubert<div class="header">
553*052d159aSCy Schubert<p>
554*052d159aSCy 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>
556*052d159aSCy Schubert<a name="jaildir-option-_0028_002di_0029"></a>
557*052d159aSCy Schubert<h4 class="subsection">1.1.10 jaildir option (-i)</h4>
558*052d159aSCy Schubert<a name="index-ntpd_002djaildir"></a>
559a25439b6SCy Schubert
560*052d159aSCy Schubert<p>This is the &ldquo;jail directory&rdquo; option.
5612b15cb3dSCy SchubertThis option takes a string argument.
562*052d159aSCy Schubert</p>
563*052d159aSCy Schubert<p>This option has some usage constraints.  It:
564*052d159aSCy Schubert</p><ul>
5652b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
566*052d159aSCy 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>).
580*052d159aSCy Schubert</p><hr>
581*052d159aSCy Schubert<a name="ntpd-interface"></a>
582*052d159aSCy Schubert<div class="header">
583*052d159aSCy Schubert<p>
584*052d159aSCy 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>
586*052d159aSCy Schubert<a name="interface-option-_0028_002dI_0029"></a>
587*052d159aSCy Schubert<h4 class="subsection">1.1.11 interface option (-I)</h4>
588*052d159aSCy Schubert<a name="index-ntpd_002dinterface"></a>
5892b15cb3dSCy Schubert
590*052d159aSCy Schubert<p>This is the &ldquo;listen on an interface name or address&rdquo; option.
591*052d159aSCy SchubertThis option takes a string argument <samp>iface</samp>.
592*052d159aSCy Schubert</p>
593*052d159aSCy Schubert<p>This option has some usage constraints.  It:
594*052d159aSCy Schubert</p><ul>
5952b15cb3dSCy Schubert<li> may appear an unlimited number of times.
596*052d159aSCy 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.
603*052d159aSCy Schubert</p><hr>
604*052d159aSCy Schubert<a name="ntpd-keyfile"></a>
605*052d159aSCy Schubert<div class="header">
606*052d159aSCy Schubert<p>
607*052d159aSCy 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>
609*052d159aSCy Schubert<a name="keyfile-option-_0028_002dk_0029"></a>
610*052d159aSCy Schubert<h4 class="subsection">1.1.12 keyfile option (-k)</h4>
611*052d159aSCy Schubert<a name="index-ntpd_002dkeyfile"></a>
6122b15cb3dSCy Schubert
613*052d159aSCy 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.
616*052d159aSCy 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.
621*052d159aSCy Schubert</p><hr>
622*052d159aSCy Schubert<a name="ntpd-logfile"></a>
623*052d159aSCy Schubert<div class="header">
624*052d159aSCy Schubert<p>
625*052d159aSCy 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>
627*052d159aSCy Schubert<a name="logfile-option-_0028_002dl_0029"></a>
628*052d159aSCy Schubert<h4 class="subsection">1.1.13 logfile option (-l)</h4>
629*052d159aSCy Schubert<a name="index-ntpd_002dlogfile"></a>
6302b15cb3dSCy Schubert
631*052d159aSCy 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.
638*052d159aSCy Schubert</p><hr>
639*052d159aSCy Schubert<a name="ntpd-novirtualips"></a>
640*052d159aSCy Schubert<div class="header">
641*052d159aSCy Schubert<p>
642*052d159aSCy 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>
644*052d159aSCy Schubert<a name="novirtualips-option-_0028_002dL_0029"></a>
645*052d159aSCy Schubert<h4 class="subsection">1.1.14 novirtualips option (-L)</h4>
646*052d159aSCy Schubert<a name="index-ntpd_002dnovirtualips"></a>
6472b15cb3dSCy Schubert
648*052d159aSCy 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.
653*052d159aSCy Schubert</p><hr>
654*052d159aSCy Schubert<a name="ntpd-modifymmtimer"></a>
655*052d159aSCy Schubert<div class="header">
656*052d159aSCy Schubert<p>
657*052d159aSCy 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>
659*052d159aSCy Schubert<a name="modifymmtimer-option-_0028_002dM_0029"></a>
660*052d159aSCy Schubert<h4 class="subsection">1.1.15 modifymmtimer option (-M)</h4>
661*052d159aSCy Schubert<a name="index-ntpd_002dmodifymmtimer"></a>
6622b15cb3dSCy Schubert
663*052d159aSCy Schubert<p>This is the &ldquo;modify multimedia timer (windows only)&rdquo; option.
664*052d159aSCy Schubert</p>
665*052d159aSCy Schubert<p>This option has some usage constraints.  It:
666*052d159aSCy Schubert</p><ul>
6672b15cb3dSCy Schubert<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
668*052d159aSCy 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.
673*052d159aSCy Schubert</p><hr>
674*052d159aSCy Schubert<a name="ntpd-nice"></a>
675*052d159aSCy Schubert<div class="header">
676*052d159aSCy Schubert<p>
677*052d159aSCy 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>
679*052d159aSCy Schubert<a name="nice-option-_0028_002dN_0029"></a>
680*052d159aSCy Schubert<h4 class="subsection">1.1.16 nice option (-N)</h4>
681*052d159aSCy Schubert<a name="index-ntpd_002dnice"></a>
6822b15cb3dSCy Schubert
683*052d159aSCy 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.
687*052d159aSCy Schubert</p><hr>
688*052d159aSCy Schubert<a name="ntpd-pidfile"></a>
689*052d159aSCy Schubert<div class="header">
690*052d159aSCy Schubert<p>
691*052d159aSCy 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>
693*052d159aSCy Schubert<a name="pidfile-option-_0028_002dp_0029"></a>
694*052d159aSCy Schubert<h4 class="subsection">1.1.17 pidfile option (-p)</h4>
695*052d159aSCy Schubert<a name="index-ntpd_002dpidfile"></a>
6962b15cb3dSCy Schubert
697*052d159aSCy 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
700*052d159aSCy 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.
705*052d159aSCy Schubert</p><hr>
706*052d159aSCy Schubert<a name="ntpd-priority"></a>
707*052d159aSCy Schubert<div class="header">
708*052d159aSCy Schubert<p>
709*052d159aSCy 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>
711*052d159aSCy Schubert<a name="priority-option-_0028_002dP_0029"></a>
712*052d159aSCy Schubert<h4 class="subsection">1.1.18 priority option (-P)</h4>
713*052d159aSCy Schubert<a name="index-ntpd_002dpriority"></a>
7142b15cb3dSCy Schubert
715*052d159aSCy 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.
722*052d159aSCy Schubert</p><hr>
723*052d159aSCy Schubert<a name="ntpd-quit"></a>
724*052d159aSCy Schubert<div class="header">
725*052d159aSCy Schubert<p>
726*052d159aSCy 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>
728*052d159aSCy Schubert<a name="quit-option-_0028_002dq_0029"></a>
729*052d159aSCy Schubert<h4 class="subsection">1.1.19 quit option (-q)</h4>
730*052d159aSCy Schubert<a name="index-ntpd_002dquit"></a>
7312b15cb3dSCy Schubert
732*052d159aSCy Schubert<p>This is the &ldquo;set the time and quit&rdquo; option.
733*052d159aSCy Schubert</p>
734*052d159aSCy Schubert<p>This option has some usage constraints.  It:
735*052d159aSCy Schubert</p><ul>
7362b15cb3dSCy Schubert<li> must not appear in combination with any of the following options:
7372b15cb3dSCy Schubertsaveconfigquit, wait-sync.
738*052d159aSCy 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.
751*052d159aSCy Schubert</p><hr>
752*052d159aSCy Schubert<a name="ntpd-propagationdelay"></a>
753*052d159aSCy Schubert<div class="header">
754*052d159aSCy Schubert<p>
755*052d159aSCy 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>
757*052d159aSCy Schubert<a name="propagationdelay-option-_0028_002dr_0029"></a>
758*052d159aSCy Schubert<h4 class="subsection">1.1.20 propagationdelay option (-r)</h4>
759*052d159aSCy Schubert<a name="index-ntpd_002dpropagationdelay"></a>
7602b15cb3dSCy Schubert
761*052d159aSCy 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.
764*052d159aSCy Schubert</p><hr>
765*052d159aSCy Schubert<a name="ntpd-saveconfigquit"></a>
766*052d159aSCy Schubert<div class="header">
767*052d159aSCy Schubert<p>
768*052d159aSCy 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>
770*052d159aSCy Schubert<a name="saveconfigquit-option"></a>
771*052d159aSCy Schubert<h4 class="subsection">1.1.21 saveconfigquit option</h4>
772*052d159aSCy Schubert<a name="index-ntpd_002dsaveconfigquit"></a>
7732b15cb3dSCy Schubert
774*052d159aSCy Schubert<p>This is the &ldquo;save parsed configuration and quit&rdquo; option.
7752b15cb3dSCy SchubertThis option takes a string argument.
776*052d159aSCy Schubert</p>
777*052d159aSCy Schubert<p>This option has some usage constraints.  It:
778*052d159aSCy Schubert</p><ul>
7792b15cb3dSCy Schubert<li> must be compiled in by defining <code>SAVECONFIG</code> during the compilation.
780*052d159aSCy Schubert</li><li> must not appear in combination with any of the following options:
7812b15cb3dSCy Schubertquit, wait-sync.
782*052d159aSCy 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.
787*052d159aSCy Schubert</p><hr>
788*052d159aSCy Schubert<a name="ntpd-statsdir"></a>
789*052d159aSCy Schubert<div class="header">
790*052d159aSCy Schubert<p>
791*052d159aSCy 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>
793*052d159aSCy Schubert<a name="statsdir-option-_0028_002ds_0029"></a>
794*052d159aSCy Schubert<h4 class="subsection">1.1.22 statsdir option (-s)</h4>
795*052d159aSCy Schubert<a name="index-ntpd_002dstatsdir"></a>
7962b15cb3dSCy Schubert
797*052d159aSCy 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.
803*052d159aSCy Schubert</p><hr>
804*052d159aSCy Schubert<a name="ntpd-trustedkey"></a>
805*052d159aSCy Schubert<div class="header">
806*052d159aSCy Schubert<p>
807*052d159aSCy 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>
809*052d159aSCy Schubert<a name="trustedkey-option-_0028_002dt_0029"></a>
810*052d159aSCy Schubert<h4 class="subsection">1.1.23 trustedkey option (-t)</h4>
811*052d159aSCy Schubert<a name="index-ntpd_002dtrustedkey"></a>
8122b15cb3dSCy Schubert
813*052d159aSCy Schubert<p>This is the &ldquo;trusted key number&rdquo; option.
814*052d159aSCy SchubertThis option takes a string argument <samp>tkey</samp>.
815*052d159aSCy Schubert</p>
816*052d159aSCy Schubert<p>This option has some usage constraints.  It:
817*052d159aSCy Schubert</p><ul>
8182b15cb3dSCy Schubert<li> may appear an unlimited number of times.
819*052d159aSCy Schubert</li></ul>
8202b15cb3dSCy Schubert
8212b15cb3dSCy Schubert<p>Add the specified key number to the trusted key list.
822*052d159aSCy Schubert</p><hr>
823*052d159aSCy Schubert<a name="ntpd-user"></a>
824*052d159aSCy Schubert<div class="header">
825*052d159aSCy Schubert<p>
826*052d159aSCy 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>
828*052d159aSCy Schubert<a name="user-option-_0028_002du_0029"></a>
829*052d159aSCy Schubert<h4 class="subsection">1.1.24 user option (-u)</h4>
830*052d159aSCy Schubert<a name="index-ntpd_002duser"></a>
8312b15cb3dSCy Schubert
832*052d159aSCy Schubert<p>This is the &ldquo;run as userid (or userid:groupid)&rdquo; option.
8332b15cb3dSCy SchubertThis option takes a string argument.
834*052d159aSCy Schubert</p>
835*052d159aSCy Schubert<p>This option has some usage constraints.  It:
836*052d159aSCy Schubert</p><ul>
8372b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
838*052d159aSCy 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>).
846*052d159aSCy Schubert</p><hr>
847*052d159aSCy Schubert<a name="ntpd-updateinterval"></a>
848*052d159aSCy Schubert<div class="header">
849*052d159aSCy Schubert<p>
850*052d159aSCy 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>
852*052d159aSCy Schubert<a name="updateinterval-option-_0028_002dU_0029"></a>
853*052d159aSCy Schubert<h4 class="subsection">1.1.25 updateinterval option (-U)</h4>
854*052d159aSCy Schubert<a name="index-ntpd_002dupdateinterval"></a>
8552b15cb3dSCy Schubert
856*052d159aSCy 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.
862*052d159aSCy Schubert</p><hr>
863*052d159aSCy Schubert<a name="ntpd-wait_002dsync"></a>
864*052d159aSCy Schubert<div class="header">
865*052d159aSCy Schubert<p>
866*052d159aSCy 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>
868*052d159aSCy Schubert<a name="wait_002dsync-option-_0028_002dw_0029"></a>
869*052d159aSCy Schubert<h4 class="subsection">1.1.26 wait-sync option (-w)</h4>
870*052d159aSCy Schubert<a name="index-ntpd_002dwait_002dsync"></a>
8712b15cb3dSCy Schubert
872*052d159aSCy Schubert<p>This is the &ldquo;seconds to wait for first clock sync&rdquo; option.
8732b15cb3dSCy SchubertThis option takes a number argument.
874*052d159aSCy Schubert</p>
875*052d159aSCy Schubert<p>This option has some usage constraints.  It:
876*052d159aSCy Schubert</p><ul>
8772b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_WORKING_FORK</code> during the compilation.
878*052d159aSCy Schubert</li><li> must not appear in combination with any of the following options:
8792b15cb3dSCy Schubertnofork, quit, saveconfigquit.
880*052d159aSCy Schubert</li></ul>
8812b15cb3dSCy Schubert
882*052d159aSCy 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.
890*052d159aSCy Schubert</p><hr>
891*052d159aSCy Schubert<a name="ntpd-slew"></a>
892*052d159aSCy Schubert<div class="header">
893*052d159aSCy Schubert<p>
894*052d159aSCy 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>
896*052d159aSCy Schubert<a name="slew-option-_0028_002dx_0029"></a>
897*052d159aSCy Schubert<h4 class="subsection">1.1.27 slew option (-x)</h4>
898*052d159aSCy Schubert<a name="index-ntpd_002dslew"></a>
8992b15cb3dSCy Schubert
900*052d159aSCy 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.
914*052d159aSCy Schubert</p><hr>
915*052d159aSCy Schubert<a name="ntpd-usepcc"></a>
916*052d159aSCy Schubert<div class="header">
917*052d159aSCy Schubert<p>
918*052d159aSCy 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>
920*052d159aSCy Schubert<a name="usepcc-option"></a>
921*052d159aSCy Schubert<h4 class="subsection">1.1.28 usepcc option</h4>
922*052d159aSCy Schubert<a name="index-ntpd_002dusepcc"></a>
9232b15cb3dSCy Schubert
924*052d159aSCy Schubert<p>This is the &ldquo;use cpu cycle counter (windows only)&rdquo; option.
925*052d159aSCy Schubert</p>
926*052d159aSCy Schubert<p>This option has some usage constraints.  It:
927*052d159aSCy Schubert</p><ul>
9282b15cb3dSCy Schubert<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
929*052d159aSCy 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.
935*052d159aSCy Schubert</p><hr>
936*052d159aSCy Schubert<a name="ntpd-pccfreq"></a>
937*052d159aSCy Schubert<div class="header">
938*052d159aSCy Schubert<p>
939*052d159aSCy 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>
941*052d159aSCy Schubert<a name="pccfreq-option"></a>
942*052d159aSCy Schubert<h4 class="subsection">1.1.29 pccfreq option</h4>
943*052d159aSCy Schubert<a name="index-ntpd_002dpccfreq"></a>
9442b15cb3dSCy Schubert
945*052d159aSCy Schubert<p>This is the &ldquo;force cpu cycle counter use (windows only)&rdquo; option.
9462b15cb3dSCy SchubertThis option takes a string argument.
947*052d159aSCy Schubert</p>
948*052d159aSCy Schubert<p>This option has some usage constraints.  It:
949*052d159aSCy Schubert</p><ul>
9502b15cb3dSCy Schubert<li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
951*052d159aSCy 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).
956*052d159aSCy Schubert</p><hr>
957*052d159aSCy Schubert<a name="ntpd-mdns"></a>
958*052d159aSCy Schubert<div class="header">
959*052d159aSCy Schubert<p>
960*052d159aSCy 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>
962*052d159aSCy Schubert<a name="mdns-option-_0028_002dm_0029"></a>
963*052d159aSCy Schubert<h4 class="subsection">1.1.30 mdns option (-m)</h4>
964*052d159aSCy Schubert<a name="index-ntpd_002dmdns"></a>
9652b15cb3dSCy Schubert
966*052d159aSCy Schubert<p>This is the &ldquo;register with mdns as a ntp server&rdquo; option.
967*052d159aSCy Schubert</p>
968*052d159aSCy Schubert<p>This option has some usage constraints.  It:
969*052d159aSCy Schubert</p><ul>
9702b15cb3dSCy Schubert<li> must be compiled in by defining <code>HAVE_DNSREGISTRATION</code> during the compilation.
971*052d159aSCy 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.
975*052d159aSCy Schubert</p>
9762b15cb3dSCy Schubert
977*052d159aSCy Schubert<hr>
978*052d159aSCy Schubert<a name="ntpd-config"></a>
979*052d159aSCy Schubert<div class="header">
980*052d159aSCy Schubert<p>
981*052d159aSCy 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>
983*052d159aSCy Schubert<a name="presetting_002fconfiguring-ntpd"></a>
984*052d159aSCy 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.
992*052d159aSCy Schubert</p>
9932b15cb3dSCy Schubert
9942b15cb3dSCy Schubert<p>The command line options relating to configuration and/or usage help are:
995*052d159aSCy Schubert</p>
996*052d159aSCy Schubert<a name="version-_0028_002d_0029"></a>
997*052d159aSCy 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:
1003*052d159aSCy Schubert</p>
1004*052d159aSCy Schubert<dl compact="compact">
1005*052d159aSCy Schubert<dt>&lsquo;<samp>version</samp>&rsquo;</dt>
1006*052d159aSCy Schubert<dd><p>Only print the version.  This is the default.
1007*052d159aSCy Schubert</p></dd>
1008*052d159aSCy Schubert<dt>&lsquo;<samp>copyright</samp>&rsquo;</dt>
1009*052d159aSCy Schubert<dd><p>Name the copyright usage licensing terms.
1010*052d159aSCy Schubert</p></dd>
1011*052d159aSCy Schubert<dt>&lsquo;<samp>verbose</samp>&rsquo;</dt>
1012*052d159aSCy Schubert<dd><p>Print the full copyright usage licensing terms.
1013*052d159aSCy Schubert</p></dd>
10142b15cb3dSCy Schubert</dl>
10152b15cb3dSCy Schubert
1016*052d159aSCy Schubert<hr>
1017*052d159aSCy Schubert<a name="ntpd-exit-status"></a>
1018*052d159aSCy Schubert<div class="header">
1019*052d159aSCy Schubert<p>
1020*052d159aSCy 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>
1022*052d159aSCy Schubert<a name="ntpd-exit-status-1"></a>
1023*052d159aSCy 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:
1026*052d159aSCy Schubert</p><dl compact="compact">
1027*052d159aSCy Schubert<dt>&lsquo;<samp>0 (EXIT_SUCCESS)</samp>&rsquo;</dt>
1028*052d159aSCy Schubert<dd><p>Successful program execution.
1029*052d159aSCy Schubert</p></dd>
1030*052d159aSCy Schubert<dt>&lsquo;<samp>1 (EXIT_FAILURE)</samp>&rsquo;</dt>
1031*052d159aSCy Schubert<dd><p>The operation failed or the command syntax was not valid.
1032*052d159aSCy Schubert</p></dd>
10332b15cb3dSCy Schubert</dl>
1034*052d159aSCy Schubert<hr>
1035*052d159aSCy Schubert<a name="ntpd-Usage"></a>
1036*052d159aSCy Schubert<div class="header">
1037*052d159aSCy Schubert<p>
1038*052d159aSCy 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>
1040*052d159aSCy Schubert<a name="ntpd-Usage-1"></a>
1041*052d159aSCy Schubert<h4 class="subsection">1.1.33 ntpd Usage</h4>
1042*052d159aSCy Schubert<hr>
1043*052d159aSCy Schubert<a name="ntpd-Files"></a>
1044*052d159aSCy Schubert<div class="header">
1045*052d159aSCy Schubert<p>
1046*052d159aSCy 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>
1048*052d159aSCy Schubert<a name="ntpd-Files-1"></a>
1049*052d159aSCy Schubert<h4 class="subsection">1.1.34 ntpd Files</h4>
1050*052d159aSCy Schubert<hr>
1051*052d159aSCy Schubert<a name="ntpd-See-Also"></a>
1052*052d159aSCy Schubert<div class="header">
1053*052d159aSCy Schubert<p>
1054*052d159aSCy 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>
1056*052d159aSCy Schubert<a name="ntpd-See-Also-1"></a>
1057*052d159aSCy Schubert<h4 class="subsection">1.1.35 ntpd See Also</h4>
1058*052d159aSCy Schubert<hr>
1059*052d159aSCy Schubert<a name="ntpd-Bugs"></a>
1060*052d159aSCy Schubert<div class="header">
1061*052d159aSCy Schubert<p>
1062*052d159aSCy 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>
1064*052d159aSCy Schubert<a name="ntpd-Bugs-1"></a>
1065*052d159aSCy Schubert<h4 class="subsection">1.1.36 ntpd Bugs</h4>
1066*052d159aSCy Schubert<hr>
1067*052d159aSCy Schubert<a name="ntpd-Notes"></a>
1068*052d159aSCy Schubert<div class="header">
1069*052d159aSCy Schubert<p>
1070*052d159aSCy 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>
1072*052d159aSCy Schubert<a name="ntpd-Notes-1"></a>
1073*052d159aSCy Schubert<h4 class="subsection">1.1.37 ntpd Notes</h4>
10742b15cb3dSCy Schubert
1075*052d159aSCy Schubert<hr>
10762b15cb3dSCy Schubert<a name="Usage"></a>
1077*052d159aSCy Schubert<div class="header">
1078*052d159aSCy Schubert<p>
1079*052d159aSCy 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>
1081*052d159aSCy Schubert<a name="Usage-1"></a>
1082*052d159aSCy Schubert<h3 class="section">1.2 Usage</h3>
10832b15cb3dSCy Schubert
1084*052d159aSCy Schubert<table>
1085*052d159aSCy 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>
1086*052d159aSCy 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>
1087*052d159aSCy 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>
1088*052d159aSCy 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>
1089*052d159aSCy 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>
1090*052d159aSCy 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>
1091*052d159aSCy 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>
1092*052d159aSCy 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>
1093*052d159aSCy 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>
1094*052d159aSCy Schubert</table>
1095*052d159aSCy Schubert<hr>
10962b15cb3dSCy Schubert
1097*052d159aSCy Schubert
1098*052d159aSCy Schubert
1099*052d159aSCy Schubert</body>
1100*052d159aSCy Schubert</html>
1101