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22*2b15cb3dSCy Schubert<h1 class="settitle">ntpd: Network Time Protocol (NTP) Daemon User's Manual</h1>
23*2b15cb3dSCy Schubert<div class="node">
24*2b15cb3dSCy Schubert<p><hr>
25*2b15cb3dSCy Schubert<a name="Top"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Description">ntpd Description</a>,
26*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#dir">(dir)</a>,
27*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#dir">(dir)</a>
28*2b15cb3dSCy Schubert<br>
29*2b15cb3dSCy Schubert</div>
30*2b15cb3dSCy Schubert
31*2b15cb3dSCy Schubert<h2 class="unnumbered">ntpd: Network Time Protocol (NTP) Daemon User Manual</h2>
32*2b15cb3dSCy Schubert
33*2b15cb3dSCy Schubert<p>The <code>ntpd</code> program is an operating system daemon that synchronizes the
34*2b15cb3dSCy Schubertsystem clock to remote NTP time servers or local reference clocks.
35*2b15cb3dSCy SchubertIt is a complete implementation of NTP version 4 defined by RFC-5905, but
36*2b15cb3dSCy Schubertalso retains compatible with version 3 defined by RFC-1305 and versions
37*2b15cb3dSCy Schubert1 and 2, defined by RFC-1059 and RFC-1119, respectively.
38*2b15cb3dSCy SchubertThe program can operate in any of several modes, including client/server,
39*2b15cb3dSCy Schubertsymmetric and broadcast modes, and with both symmetric-key and public-key
40*2b15cb3dSCy Schubertcryptography.
41*2b15cb3dSCy Schubert
42*2b15cb3dSCy Schubert  <p>This document applies to version 4.2.8p1 of <code>ntpd</code>.
43*2b15cb3dSCy Schubert
44*2b15cb3dSCy Schubert<ul class="menu">
45*2b15cb3dSCy Schubert<li><a accesskey="1" href="#ntpd-Description">ntpd Description</a>:             Description
46*2b15cb3dSCy Schubert<li><a accesskey="2" href="#ntpd-Invocation">ntpd Invocation</a>: 		Invoking ntpd
47*2b15cb3dSCy Schubert<li><a accesskey="3" href="#Usage">Usage</a>:                        Usage
48*2b15cb3dSCy Schubert</ul>
49*2b15cb3dSCy Schubert
50*2b15cb3dSCy Schubert<div class="node">
51*2b15cb3dSCy Schubert<p><hr>
52*2b15cb3dSCy Schubert<a name="ntpd-Description"></a>
53*2b15cb3dSCy Schubert<br>
54*2b15cb3dSCy Schubert</div>
55*2b15cb3dSCy Schubert
56*2b15cb3dSCy Schubert<!-- node-name,  next,  previous,  up -->
57*2b15cb3dSCy Schubert<h3 class="section">Description</h3>
58*2b15cb3dSCy Schubert
59*2b15cb3dSCy Schubert<p>The <code>ntpd</code> program ordinarily requires
60*2b15cb3dSCy Schuberta configuration file described at <a href="#ntp_002econf">ntp.conf</a>.
61*2b15cb3dSCy SchubertThis configuration file contains configuration commands described on
62*2b15cb3dSCy Schubertthe pages listed above.
63*2b15cb3dSCy SchubertHowever a client can discover remote servers and configure them
64*2b15cb3dSCy Schubertautomatically.
65*2b15cb3dSCy SchubertThis makes it possible to deploy a fleet of workstations without
66*2b15cb3dSCy Schubertspecifying configuration details specific to the local environment.
67*2b15cb3dSCy Schubert
68*2b15cb3dSCy Schubert  <p>The <code>ntpd</code> program normally operates continuously while adjusting the
69*2b15cb3dSCy Schubertsystem time and frequency, but in some cases this might not be
70*2b15cb3dSCy Schubertpractical.
71*2b15cb3dSCy SchubertWith the <code>-q</code> option <code>ntpd</code> operates as in continuous mode, but
72*2b15cb3dSCy Schubertexits just after setting the clock for the first time.
73*2b15cb3dSCy SchubertMost applications will probably want to specify the <code>iburst</code>
74*2b15cb3dSCy Schubertoption with the <code>server</code> command.
75*2b15cb3dSCy SchubertWith this option an initial volley of messages is exchanged to
76*2b15cb3dSCy Schubertgroom the data and set the clock in about ten seconds' time.
77*2b15cb3dSCy SchubertIf nothing is heard after a few minutes' time,
78*2b15cb3dSCy Schubertthe daemon times out and exits without setting the clock.
79*2b15cb3dSCy Schubert
80*2b15cb3dSCy Schubert<div class="node">
81*2b15cb3dSCy Schubert<p><hr>
82*2b15cb3dSCy Schubert<a name="ntpd-Invocation"></a>
83*2b15cb3dSCy Schubert<br>
84*2b15cb3dSCy Schubert</div>
85*2b15cb3dSCy Schubert
86*2b15cb3dSCy Schubert<h3 class="section">Invoking ntpd</h3>
87*2b15cb3dSCy Schubert
88*2b15cb3dSCy Schubert<p><a name="index-ntpd-1"></a><a name="index-NTP-daemon-program-2"></a>
89*2b15cb3dSCy Schubert
90*2b15cb3dSCy Schubert  <p>The
91*2b15cb3dSCy Schubert<code>ntpd</code>
92*2b15cb3dSCy Schubertutility is an operating system daemon which sets
93*2b15cb3dSCy Schubertand maintains the system time of day in synchronism with Internet
94*2b15cb3dSCy Schubertstandard time servers.
95*2b15cb3dSCy SchubertIt is a complete implementation of the
96*2b15cb3dSCy SchubertNetwork Time Protocol (NTP) version 4, as defined by RFC-5905,
97*2b15cb3dSCy Schubertbut also retains compatibility with
98*2b15cb3dSCy Schubertversion 3, as defined by RFC-1305, and versions 1
99*2b15cb3dSCy Schubertand 2, as defined by RFC-1059 and RFC-1119, respectively.
100*2b15cb3dSCy Schubert
101*2b15cb3dSCy Schubert  <p>The
102*2b15cb3dSCy Schubert<code>ntpd</code>
103*2b15cb3dSCy Schubertutility does most computations in 64-bit floating point
104*2b15cb3dSCy Schubertarithmetic and does relatively clumsy 64-bit fixed point operations
105*2b15cb3dSCy Schubertonly when necessary to preserve the ultimate precision, about 232
106*2b15cb3dSCy Schubertpicoseconds.
107*2b15cb3dSCy SchubertWhile the ultimate precision is not achievable with
108*2b15cb3dSCy Schubertordinary workstations and networks of today, it may be required
109*2b15cb3dSCy Schubertwith future gigahertz CPU clocks and gigabit LANs.
110*2b15cb3dSCy Schubert
111*2b15cb3dSCy Schubert  <p>Ordinarily,
112*2b15cb3dSCy Schubert<code>ntpd</code>
113*2b15cb3dSCy Schubertreads the
114*2b15cb3dSCy Schubert<code>ntp.conf(5)</code>
115*2b15cb3dSCy Schubertconfiguration file at startup time in order to determine the
116*2b15cb3dSCy Schubertsynchronization sources and operating modes.
117*2b15cb3dSCy SchubertIt is also possible to
118*2b15cb3dSCy Schubertspecify a working, although limited, configuration entirely on the
119*2b15cb3dSCy Schubertcommand line, obviating the need for a configuration file.
120*2b15cb3dSCy SchubertThis may
121*2b15cb3dSCy Schubertbe particularly useful when the local host is to be configured as a
122*2b15cb3dSCy Schubertbroadcast/multicast client, with all peers being determined by
123*2b15cb3dSCy Schubertlistening to broadcasts at run time.
124*2b15cb3dSCy Schubert
125*2b15cb3dSCy Schubert  <p>If NetInfo support is built into
126*2b15cb3dSCy Schubert<code>ntpd</code>
127*2b15cb3dSCy Schubertthen
128*2b15cb3dSCy Schubert<code>ntpd</code>
129*2b15cb3dSCy Schubertwill attempt to read its configuration from the
130*2b15cb3dSCy SchubertNetInfo if the default
131*2b15cb3dSCy Schubert<code>ntp.conf(5)</code>
132*2b15cb3dSCy Schubertfile cannot be read and no file is
133*2b15cb3dSCy Schubertspecified by the
134*2b15cb3dSCy Schubert<code>-c</code>
135*2b15cb3dSCy Schubertoption.
136*2b15cb3dSCy Schubert
137*2b15cb3dSCy Schubert  <p>Various internal
138*2b15cb3dSCy Schubert<code>ntpd</code>
139*2b15cb3dSCy Schubertvariables can be displayed and
140*2b15cb3dSCy Schubertconfiguration options altered while the
141*2b15cb3dSCy Schubert<code>ntpd</code>
142*2b15cb3dSCy Schubertis running
143*2b15cb3dSCy Schubertusing the
144*2b15cb3dSCy Schubert<code>ntpq(1ntpqmdoc)</code>
145*2b15cb3dSCy Schubertand
146*2b15cb3dSCy Schubert<code>ntpdc(1ntpdcmdoc)</code>
147*2b15cb3dSCy Schubertutility programs.
148*2b15cb3dSCy Schubert
149*2b15cb3dSCy Schubert  <p>When
150*2b15cb3dSCy Schubert<code>ntpd</code>
151*2b15cb3dSCy Schubertstarts it looks at the value of
152*2b15cb3dSCy Schubert<code>umask(2)</code>,
153*2b15cb3dSCy Schubertand if zero
154*2b15cb3dSCy Schubert<code>ntpd</code>
155*2b15cb3dSCy Schubertwill set the
156*2b15cb3dSCy Schubert<code>umask(2)</code>
157*2b15cb3dSCy Schubertto 022.
158*2b15cb3dSCy Schubert
159*2b15cb3dSCy Schubert  <p>This section was generated by <strong>AutoGen</strong>,
160*2b15cb3dSCy Schubertusing the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntpd</code> program.
161*2b15cb3dSCy SchubertThis software is released under the NTP license, &lt;http://ntp.org/license&gt;.
162*2b15cb3dSCy Schubert
163*2b15cb3dSCy Schubert<ul class="menu">
164*2b15cb3dSCy Schubert<li><a accesskey="1" href="#ntpd-usage">ntpd usage</a>:                   ntpd help/usage (<span class="option">--help</span>)
165*2b15cb3dSCy Schubert<li><a accesskey="2" href="#ntpd-ipv4">ntpd ipv4</a>:                    ipv4 option (-4)
166*2b15cb3dSCy Schubert<li><a accesskey="3" href="#ntpd-ipv6">ntpd ipv6</a>:                    ipv6 option (-6)
167*2b15cb3dSCy Schubert<li><a accesskey="4" href="#ntpd-authreq">ntpd authreq</a>:                 authreq option (-a)
168*2b15cb3dSCy Schubert<li><a accesskey="5" href="#ntpd-authnoreq">ntpd authnoreq</a>:               authnoreq option (-A)
169*2b15cb3dSCy Schubert<li><a accesskey="6" href="#ntpd-configfile">ntpd configfile</a>:              configfile option (-c)
170*2b15cb3dSCy Schubert<li><a accesskey="7" href="#ntpd-driftfile">ntpd driftfile</a>:               driftfile option (-f)
171*2b15cb3dSCy Schubert<li><a accesskey="8" href="#ntpd-panicgate">ntpd panicgate</a>:               panicgate option (-g)
172*2b15cb3dSCy Schubert<li><a accesskey="9" href="#ntpd-jaildir">ntpd jaildir</a>:                 jaildir option (-i)
173*2b15cb3dSCy Schubert<li><a href="#ntpd-interface">ntpd interface</a>:               interface option (-I)
174*2b15cb3dSCy Schubert<li><a href="#ntpd-keyfile">ntpd keyfile</a>:                 keyfile option (-k)
175*2b15cb3dSCy Schubert<li><a href="#ntpd-logfile">ntpd logfile</a>:                 logfile option (-l)
176*2b15cb3dSCy Schubert<li><a href="#ntpd-novirtualips">ntpd novirtualips</a>:            novirtualips option (-L)
177*2b15cb3dSCy Schubert<li><a href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>:           modifymmtimer option (-M)
178*2b15cb3dSCy Schubert<li><a href="#ntpd-nice">ntpd nice</a>:                    nice option (-N)
179*2b15cb3dSCy Schubert<li><a href="#ntpd-pidfile">ntpd pidfile</a>:                 pidfile option (-p)
180*2b15cb3dSCy Schubert<li><a href="#ntpd-priority">ntpd priority</a>:                priority option (-P)
181*2b15cb3dSCy Schubert<li><a href="#ntpd-quit">ntpd quit</a>:                    quit option (-q)
182*2b15cb3dSCy Schubert<li><a href="#ntpd-propagationdelay">ntpd propagationdelay</a>:        propagationdelay option (-r)
183*2b15cb3dSCy Schubert<li><a href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>:          saveconfigquit option
184*2b15cb3dSCy Schubert<li><a href="#ntpd-statsdir">ntpd statsdir</a>:                statsdir option (-s)
185*2b15cb3dSCy Schubert<li><a href="#ntpd-trustedkey">ntpd trustedkey</a>:              trustedkey option (-t)
186*2b15cb3dSCy Schubert<li><a href="#ntpd-user">ntpd user</a>:                    user option (-u)
187*2b15cb3dSCy Schubert<li><a href="#ntpd-updateinterval">ntpd updateinterval</a>:          updateinterval option (-U)
188*2b15cb3dSCy Schubert<li><a href="#ntpd-wait_002dsync">ntpd wait-sync</a>:               wait-sync option (-w)
189*2b15cb3dSCy Schubert<li><a href="#ntpd-slew">ntpd slew</a>:                    slew option (-x)
190*2b15cb3dSCy Schubert<li><a href="#ntpd-usepcc">ntpd usepcc</a>:                  usepcc option
191*2b15cb3dSCy Schubert<li><a href="#ntpd-pccfreq">ntpd pccfreq</a>:                 pccfreq option
192*2b15cb3dSCy Schubert<li><a href="#ntpd-mdns">ntpd mdns</a>:                    mdns option (-m)
193*2b15cb3dSCy Schubert<li><a href="#ntpd-config">ntpd config</a>:                  presetting/configuring ntpd
194*2b15cb3dSCy Schubert<li><a href="#ntpd-exit-status">ntpd exit status</a>:             exit status
195*2b15cb3dSCy Schubert<li><a href="#ntpd-Usage">ntpd Usage</a>:                   Usage
196*2b15cb3dSCy Schubert<li><a href="#ntpd-Files">ntpd Files</a>:                   Files
197*2b15cb3dSCy Schubert<li><a href="#ntpd-See-Also">ntpd See Also</a>:                See Also
198*2b15cb3dSCy Schubert<li><a href="#ntpd-Bugs">ntpd Bugs</a>:                    Bugs
199*2b15cb3dSCy Schubert<li><a href="#ntpd-Notes">ntpd Notes</a>:                   Notes
200*2b15cb3dSCy Schubert</ul>
201*2b15cb3dSCy Schubert
202*2b15cb3dSCy Schubert<div class="node">
203*2b15cb3dSCy Schubert<p><hr>
204*2b15cb3dSCy Schubert<a name="ntpd-usage"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-ipv4">ntpd ipv4</a>,
205*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
206*2b15cb3dSCy Schubert<br>
207*2b15cb3dSCy Schubert</div>
208*2b15cb3dSCy Schubert
209*2b15cb3dSCy Schubert<h4 class="subsection">ntpd help/usage (<span class="option">--help</span>)</h4>
210*2b15cb3dSCy Schubert
211*2b15cb3dSCy Schubert<p><a name="index-ntpd-help-3"></a>
212*2b15cb3dSCy SchubertThis is the automatically generated usage text for ntpd.
213*2b15cb3dSCy Schubert
214*2b15cb3dSCy Schubert  <p>The text printed is the same whether selected with the <code>help</code> option
215*2b15cb3dSCy Schubert(<span class="option">--help</span>) or the <code>more-help</code> option (<span class="option">--more-help</span>).  <code>more-help</code> will print
216*2b15cb3dSCy Schubertthe usage text by passing it through a pager program.
217*2b15cb3dSCy Schubert<code>more-help</code> is disabled on platforms without a working
218*2b15cb3dSCy Schubert<code>fork(2)</code> function.  The <code>PAGER</code> environment variable is
219*2b15cb3dSCy Schubertused to select the program, defaulting to <span class="file">more</span>.  Both will exit
220*2b15cb3dSCy Schubertwith a status code of 0.
221*2b15cb3dSCy Schubert
222*2b15cb3dSCy Schubert<pre class="example">ntpd - NTP daemon program - Ver. 4.2.8p1-RC2
223*2b15cb3dSCy SchubertUsage:  ntpd [ -&lt;flag&gt; [&lt;val&gt;] | --&lt;name&gt;[{=| }&lt;val&gt;] ]... \
224*2b15cb3dSCy Schubert                [ &lt;server1&gt; ... &lt;serverN&gt; ]
225*2b15cb3dSCy Schubert  Flg Arg Option-Name    Description
226*2b15cb3dSCy Schubert   -4 no  ipv4           Force IPv4 DNS name resolution
227*2b15cb3dSCy Schubert                                - prohibits the option 'ipv6'
228*2b15cb3dSCy Schubert   -6 no  ipv6           Force IPv6 DNS name resolution
229*2b15cb3dSCy Schubert                                - prohibits the option 'ipv4'
230*2b15cb3dSCy Schubert   -a no  authreq        Require crypto authentication
231*2b15cb3dSCy Schubert                                - prohibits the option 'authnoreq'
232*2b15cb3dSCy Schubert   -A no  authnoreq      Do not require crypto authentication
233*2b15cb3dSCy Schubert                                - prohibits the option 'authreq'
234*2b15cb3dSCy Schubert   -b no  bcastsync      Allow us to sync to broadcast servers
235*2b15cb3dSCy Schubert   -c Str configfile     configuration file name
236*2b15cb3dSCy Schubert   -d no  debug-level    Increase debug verbosity level
237*2b15cb3dSCy Schubert                                - may appear multiple times
238*2b15cb3dSCy Schubert   -D Num set-debug-level Set the debug verbosity level
239*2b15cb3dSCy Schubert                                - may appear multiple times
240*2b15cb3dSCy Schubert   -f Str driftfile      frequency drift file name
241*2b15cb3dSCy Schubert   -g no  panicgate      Allow the first adjustment to be Big
242*2b15cb3dSCy Schubert                                - may appear multiple times
243*2b15cb3dSCy Schubert   -i Str jaildir        Jail directory
244*2b15cb3dSCy Schubert   -I Str interface      Listen on an interface name or address
245*2b15cb3dSCy Schubert                                - may appear multiple times
246*2b15cb3dSCy Schubert   -k Str keyfile        path to symmetric keys
247*2b15cb3dSCy Schubert   -l Str logfile        path to the log file
248*2b15cb3dSCy Schubert   -L no  novirtualips   Do not listen to virtual interfaces
249*2b15cb3dSCy Schubert   -n no  nofork         Do not fork
250*2b15cb3dSCy Schubert                                - prohibits the option 'wait-sync'
251*2b15cb3dSCy Schubert   -N no  nice           Run at high priority
252*2b15cb3dSCy Schubert   -p Str pidfile        path to the PID file
253*2b15cb3dSCy Schubert   -P Num priority       Process priority
254*2b15cb3dSCy Schubert   -q no  quit           Set the time and quit
255*2b15cb3dSCy Schubert                                - prohibits these options:
256*2b15cb3dSCy Schubert                                saveconfigquit
257*2b15cb3dSCy Schubert                                wait-sync
258*2b15cb3dSCy Schubert   -r Str propagationdelay Broadcast/propagation delay
259*2b15cb3dSCy Schubert      Str saveconfigquit Save parsed configuration and quit
260*2b15cb3dSCy Schubert                                - prohibits these options:
261*2b15cb3dSCy Schubert                                quit
262*2b15cb3dSCy Schubert                                wait-sync
263*2b15cb3dSCy Schubert   -s Str statsdir       Statistics file location
264*2b15cb3dSCy Schubert   -t Str trustedkey     Trusted key number
265*2b15cb3dSCy Schubert                                - may appear multiple times
266*2b15cb3dSCy Schubert   -u Str user           Run as userid (or userid:groupid)
267*2b15cb3dSCy Schubert   -U Num updateinterval interval in seconds between scans for new or dropped interfaces
268*2b15cb3dSCy Schubert      Str var            make ARG an ntp variable (RW)
269*2b15cb3dSCy Schubert                                - may appear multiple times
270*2b15cb3dSCy Schubert      Str dvar           make ARG an ntp variable (RW|DEF)
271*2b15cb3dSCy Schubert                                - may appear multiple times
272*2b15cb3dSCy Schubert   -w Num wait-sync      Seconds to wait for first clock sync
273*2b15cb3dSCy Schubert                                - prohibits these options:
274*2b15cb3dSCy Schubert                                nofork
275*2b15cb3dSCy Schubert                                quit
276*2b15cb3dSCy Schubert                                saveconfigquit
277*2b15cb3dSCy Schubert   -x no  slew           Slew up to 600 seconds
278*2b15cb3dSCy Schubert      opt version        output version information and exit
279*2b15cb3dSCy Schubert   -? no  help           display extended usage information and exit
280*2b15cb3dSCy Schubert   -! no  more-help      extended usage information passed thru pager
281*2b15cb3dSCy Schubert
282*2b15cb3dSCy SchubertOptions are specified by doubled hyphens and their name or by a single
283*2b15cb3dSCy Schuberthyphen and the flag character.
284*2b15cb3dSCy Schubert
285*2b15cb3dSCy Schubert
286*2b15cb3dSCy SchubertThe following option preset mechanisms are supported:
287*2b15cb3dSCy Schubert - examining environment variables named NTPD_*
288*2b15cb3dSCy Schubert
289*2b15cb3dSCy SchubertPlease send bug reports to:  &lt;http://bugs.ntp.org, bugs@ntp.org&gt;
290*2b15cb3dSCy Schubert</pre>
291*2b15cb3dSCy Schubert  <div class="node">
292*2b15cb3dSCy Schubert<p><hr>
293*2b15cb3dSCy Schubert<a name="ntpd-ipv4"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-ipv6">ntpd ipv6</a>,
294*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-usage">ntpd usage</a>,
295*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
296*2b15cb3dSCy Schubert<br>
297*2b15cb3dSCy Schubert</div>
298*2b15cb3dSCy Schubert
299*2b15cb3dSCy Schubert<h4 class="subsection">ipv4 option (-4)</h4>
300*2b15cb3dSCy Schubert
301*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dipv4-4"></a>
302*2b15cb3dSCy SchubertThis is the &ldquo;force ipv4 dns name resolution&rdquo; option.
303*2b15cb3dSCy Schubert
304*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
305*2b15cb3dSCy Schubert     <ul>
306*2b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
307*2b15cb3dSCy Schubertipv6.
308*2b15cb3dSCy Schubert</ul>
309*2b15cb3dSCy Schubert
310*2b15cb3dSCy Schubert  <p>Force DNS resolution of following host names on the command line
311*2b15cb3dSCy Schubertto the IPv4 namespace.
312*2b15cb3dSCy Schubert<div class="node">
313*2b15cb3dSCy Schubert<p><hr>
314*2b15cb3dSCy Schubert<a name="ntpd-ipv6"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-authreq">ntpd authreq</a>,
315*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-ipv4">ntpd ipv4</a>,
316*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
317*2b15cb3dSCy Schubert<br>
318*2b15cb3dSCy Schubert</div>
319*2b15cb3dSCy Schubert
320*2b15cb3dSCy Schubert<h4 class="subsection">ipv6 option (-6)</h4>
321*2b15cb3dSCy Schubert
322*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dipv6-5"></a>
323*2b15cb3dSCy SchubertThis is the &ldquo;force ipv6 dns name resolution&rdquo; option.
324*2b15cb3dSCy Schubert
325*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
326*2b15cb3dSCy Schubert     <ul>
327*2b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
328*2b15cb3dSCy Schubertipv4.
329*2b15cb3dSCy Schubert</ul>
330*2b15cb3dSCy Schubert
331*2b15cb3dSCy Schubert  <p>Force DNS resolution of following host names on the command line
332*2b15cb3dSCy Schubertto the IPv6 namespace.
333*2b15cb3dSCy Schubert<div class="node">
334*2b15cb3dSCy Schubert<p><hr>
335*2b15cb3dSCy Schubert<a name="ntpd-authreq"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-authnoreq">ntpd authnoreq</a>,
336*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-ipv6">ntpd ipv6</a>,
337*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
338*2b15cb3dSCy Schubert<br>
339*2b15cb3dSCy Schubert</div>
340*2b15cb3dSCy Schubert
341*2b15cb3dSCy Schubert<h4 class="subsection">authreq option (-a)</h4>
342*2b15cb3dSCy Schubert
343*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dauthreq-6"></a>
344*2b15cb3dSCy SchubertThis is the &ldquo;require crypto authentication&rdquo; option.
345*2b15cb3dSCy Schubert
346*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
347*2b15cb3dSCy Schubert     <ul>
348*2b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
349*2b15cb3dSCy Schubertauthnoreq.
350*2b15cb3dSCy Schubert</ul>
351*2b15cb3dSCy Schubert
352*2b15cb3dSCy Schubert  <p>Require cryptographic authentication for broadcast client,
353*2b15cb3dSCy Schubertmulticast client and symmetric passive associations.
354*2b15cb3dSCy SchubertThis is the default.
355*2b15cb3dSCy Schubert<div class="node">
356*2b15cb3dSCy Schubert<p><hr>
357*2b15cb3dSCy Schubert<a name="ntpd-authnoreq"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-configfile">ntpd configfile</a>,
358*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-authreq">ntpd authreq</a>,
359*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
360*2b15cb3dSCy Schubert<br>
361*2b15cb3dSCy Schubert</div>
362*2b15cb3dSCy Schubert
363*2b15cb3dSCy Schubert<h4 class="subsection">authnoreq option (-A)</h4>
364*2b15cb3dSCy Schubert
365*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dauthnoreq-7"></a>
366*2b15cb3dSCy SchubertThis is the &ldquo;do not require crypto authentication&rdquo; option.
367*2b15cb3dSCy Schubert
368*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
369*2b15cb3dSCy Schubert     <ul>
370*2b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
371*2b15cb3dSCy Schubertauthreq.
372*2b15cb3dSCy Schubert</ul>
373*2b15cb3dSCy Schubert
374*2b15cb3dSCy Schubert  <p>Do not require cryptographic authentication for broadcast client,
375*2b15cb3dSCy Schubertmulticast client and symmetric passive associations.
376*2b15cb3dSCy SchubertThis is almost never a good idea.
377*2b15cb3dSCy Schubert<div class="node">
378*2b15cb3dSCy Schubert<p><hr>
379*2b15cb3dSCy Schubert<a name="ntpd-configfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-driftfile">ntpd driftfile</a>,
380*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-authnoreq">ntpd authnoreq</a>,
381*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
382*2b15cb3dSCy Schubert<br>
383*2b15cb3dSCy Schubert</div>
384*2b15cb3dSCy Schubert
385*2b15cb3dSCy Schubert<h4 class="subsection">configfile option (-c)</h4>
386*2b15cb3dSCy Schubert
387*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dconfigfile-8"></a>
388*2b15cb3dSCy SchubertThis is the &ldquo;configuration file name&rdquo; option.
389*2b15cb3dSCy SchubertThis option takes a string argument.
390*2b15cb3dSCy SchubertThe name and path of the configuration file,
391*2b15cb3dSCy Schubert<span class="file">/etc/ntp.conf</span>
392*2b15cb3dSCy Schubertby default.
393*2b15cb3dSCy Schubert<div class="node">
394*2b15cb3dSCy Schubert<p><hr>
395*2b15cb3dSCy Schubert<a name="ntpd-driftfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-panicgate">ntpd panicgate</a>,
396*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-configfile">ntpd configfile</a>,
397*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
398*2b15cb3dSCy Schubert<br>
399*2b15cb3dSCy Schubert</div>
400*2b15cb3dSCy Schubert
401*2b15cb3dSCy Schubert<h4 class="subsection">driftfile option (-f)</h4>
402*2b15cb3dSCy Schubert
403*2b15cb3dSCy Schubert<p><a name="index-ntpd_002ddriftfile-9"></a>
404*2b15cb3dSCy SchubertThis is the &ldquo;frequency drift file name&rdquo; option.
405*2b15cb3dSCy SchubertThis option takes a string argument.
406*2b15cb3dSCy SchubertThe name and path of the frequency file,
407*2b15cb3dSCy Schubert<span class="file">/etc/ntp.drift</span>
408*2b15cb3dSCy Schubertby default.
409*2b15cb3dSCy SchubertThis is the same operation as the
410*2b15cb3dSCy Schubert<code>driftfile</code> <kbd>driftfile</kbd>
411*2b15cb3dSCy Schubertconfiguration specification in the
412*2b15cb3dSCy Schubert<span class="file">/etc/ntp.conf</span>
413*2b15cb3dSCy Schubertfile.
414*2b15cb3dSCy Schubert<div class="node">
415*2b15cb3dSCy Schubert<p><hr>
416*2b15cb3dSCy Schubert<a name="ntpd-panicgate"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-jaildir">ntpd jaildir</a>,
417*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-driftfile">ntpd driftfile</a>,
418*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
419*2b15cb3dSCy Schubert<br>
420*2b15cb3dSCy Schubert</div>
421*2b15cb3dSCy Schubert
422*2b15cb3dSCy Schubert<h4 class="subsection">panicgate option (-g)</h4>
423*2b15cb3dSCy Schubert
424*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dpanicgate-10"></a>
425*2b15cb3dSCy SchubertThis is the &ldquo;allow the first adjustment to be big&rdquo; option.
426*2b15cb3dSCy Schubert
427*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
428*2b15cb3dSCy Schubert     <ul>
429*2b15cb3dSCy Schubert<li>may appear an unlimited number of times.
430*2b15cb3dSCy Schubert</ul>
431*2b15cb3dSCy Schubert
432*2b15cb3dSCy Schubert  <p>Normally,
433*2b15cb3dSCy Schubert<code>ntpd</code>
434*2b15cb3dSCy 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,
435*2b15cb3dSCy Schubert<code>ntpd</code>
436*2b15cb3dSCy Schubertwill exit with a message to the system log. This option can be used with the
437*2b15cb3dSCy Schubert<code>-q</code>
438*2b15cb3dSCy Schubertand
439*2b15cb3dSCy Schubert<code>-x</code>
440*2b15cb3dSCy Schubertoptions.
441*2b15cb3dSCy SchubertSee the
442*2b15cb3dSCy Schubert<code>tinker</code>
443*2b15cb3dSCy Schubertconfiguration file directive for other options.
444*2b15cb3dSCy Schubert<div class="node">
445*2b15cb3dSCy Schubert<p><hr>
446*2b15cb3dSCy Schubert<a name="ntpd-jaildir"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-interface">ntpd interface</a>,
447*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-panicgate">ntpd panicgate</a>,
448*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
449*2b15cb3dSCy Schubert<br>
450*2b15cb3dSCy Schubert</div>
451*2b15cb3dSCy Schubert
452*2b15cb3dSCy Schubert<h4 class="subsection">jaildir option (-i)</h4>
453*2b15cb3dSCy Schubert
454*2b15cb3dSCy Schubert<p><a name="index-ntpd_002djaildir-11"></a>
455*2b15cb3dSCy SchubertThis is the &ldquo;jail directory&rdquo; option.
456*2b15cb3dSCy SchubertThis option takes a string argument.
457*2b15cb3dSCy Schubert
458*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
459*2b15cb3dSCy Schubert     <ul>
460*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
461*2b15cb3dSCy Schubert</ul>
462*2b15cb3dSCy Schubert
463*2b15cb3dSCy Schubert  <p>Chroot the server to the directory
464*2b15cb3dSCy Schubert<kbd>jaildir</kbd>
465*2b15cb3dSCy Schubert.
466*2b15cb3dSCy SchubertThis option also implies that the server attempts to drop root privileges at startup.
467*2b15cb3dSCy SchubertYou may need to also specify a
468*2b15cb3dSCy Schubert<code>-u</code>
469*2b15cb3dSCy Schubertoption.
470*2b15cb3dSCy SchubertThis option is only available if the OS supports adjusting the clock
471*2b15cb3dSCy Schubertwithout full root privileges.
472*2b15cb3dSCy SchubertThis option is supported under NetBSD (configure with
473*2b15cb3dSCy Schubert<code>--enable-clockctl</code>) or Linux (configure with
474*2b15cb3dSCy Schubert<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
475*2b15cb3dSCy Schubert<div class="node">
476*2b15cb3dSCy Schubert<p><hr>
477*2b15cb3dSCy Schubert<a name="ntpd-interface"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-keyfile">ntpd keyfile</a>,
478*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-jaildir">ntpd jaildir</a>,
479*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
480*2b15cb3dSCy Schubert<br>
481*2b15cb3dSCy Schubert</div>
482*2b15cb3dSCy Schubert
483*2b15cb3dSCy Schubert<h4 class="subsection">interface option (-I)</h4>
484*2b15cb3dSCy Schubert
485*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dinterface-12"></a>
486*2b15cb3dSCy SchubertThis is the &ldquo;listen on an interface name or address&rdquo; option.
487*2b15cb3dSCy SchubertThis option takes a string argument <span class="file">iface</span>.
488*2b15cb3dSCy Schubert
489*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
490*2b15cb3dSCy Schubert     <ul>
491*2b15cb3dSCy Schubert<li>may appear an unlimited number of times.
492*2b15cb3dSCy Schubert</ul>
493*2b15cb3dSCy Schubert
494*2b15cb3dSCy Schubert  <p>Open the network address given, or all the addresses associated with the
495*2b15cb3dSCy Schubertgiven interface name.  This option may appear multiple times.  This option
496*2b15cb3dSCy Schubertalso implies not opening other addresses, except wildcard and localhost.
497*2b15cb3dSCy SchubertThis option is deprecated. Please consider using the configuration file
498*2b15cb3dSCy Schubert<code>interface</code> command, which is more versatile.
499*2b15cb3dSCy Schubert<div class="node">
500*2b15cb3dSCy Schubert<p><hr>
501*2b15cb3dSCy Schubert<a name="ntpd-keyfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-logfile">ntpd logfile</a>,
502*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-interface">ntpd interface</a>,
503*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
504*2b15cb3dSCy Schubert<br>
505*2b15cb3dSCy Schubert</div>
506*2b15cb3dSCy Schubert
507*2b15cb3dSCy Schubert<h4 class="subsection">keyfile option (-k)</h4>
508*2b15cb3dSCy Schubert
509*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dkeyfile-13"></a>
510*2b15cb3dSCy SchubertThis is the &ldquo;path to symmetric keys&rdquo; option.
511*2b15cb3dSCy SchubertThis option takes a string argument.
512*2b15cb3dSCy SchubertSpecify the name and path of the symmetric key file.
513*2b15cb3dSCy Schubert<span class="file">/etc/ntp.keys</span>
514*2b15cb3dSCy Schubertis the default.
515*2b15cb3dSCy SchubertThis is the same operation as the
516*2b15cb3dSCy Schubert<code>keys</code> <kbd>keyfile</kbd>
517*2b15cb3dSCy Schubertconfiguration file directive.
518*2b15cb3dSCy Schubert<div class="node">
519*2b15cb3dSCy Schubert<p><hr>
520*2b15cb3dSCy Schubert<a name="ntpd-logfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-novirtualips">ntpd novirtualips</a>,
521*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-keyfile">ntpd keyfile</a>,
522*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
523*2b15cb3dSCy Schubert<br>
524*2b15cb3dSCy Schubert</div>
525*2b15cb3dSCy Schubert
526*2b15cb3dSCy Schubert<h4 class="subsection">logfile option (-l)</h4>
527*2b15cb3dSCy Schubert
528*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dlogfile-14"></a>
529*2b15cb3dSCy SchubertThis is the &ldquo;path to the log file&rdquo; option.
530*2b15cb3dSCy SchubertThis option takes a string argument.
531*2b15cb3dSCy SchubertSpecify the name and path of the log file.
532*2b15cb3dSCy SchubertThe default is the system log file.
533*2b15cb3dSCy SchubertThis is the same operation as the
534*2b15cb3dSCy Schubert<code>logfile</code> <kbd>logfile</kbd>
535*2b15cb3dSCy Schubertconfiguration file directive.
536*2b15cb3dSCy Schubert<div class="node">
537*2b15cb3dSCy Schubert<p><hr>
538*2b15cb3dSCy Schubert<a name="ntpd-novirtualips"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>,
539*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-logfile">ntpd logfile</a>,
540*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
541*2b15cb3dSCy Schubert<br>
542*2b15cb3dSCy Schubert</div>
543*2b15cb3dSCy Schubert
544*2b15cb3dSCy Schubert<h4 class="subsection">novirtualips option (-L)</h4>
545*2b15cb3dSCy Schubert
546*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dnovirtualips-15"></a>
547*2b15cb3dSCy SchubertThis is the &ldquo;do not listen to virtual interfaces&rdquo; option.
548*2b15cb3dSCy SchubertDo not listen to virtual interfaces, defined as those with
549*2b15cb3dSCy Schubertnames containing a colon.  This option is deprecated.  Please
550*2b15cb3dSCy Schubertconsider using the configuration file <code>interface</code> command, which
551*2b15cb3dSCy Schubertis more versatile.
552*2b15cb3dSCy Schubert<div class="node">
553*2b15cb3dSCy Schubert<p><hr>
554*2b15cb3dSCy Schubert<a name="ntpd-modifymmtimer"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-nice">ntpd nice</a>,
555*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-novirtualips">ntpd novirtualips</a>,
556*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
557*2b15cb3dSCy Schubert<br>
558*2b15cb3dSCy Schubert</div>
559*2b15cb3dSCy Schubert
560*2b15cb3dSCy Schubert<h4 class="subsection">modifymmtimer option (-M)</h4>
561*2b15cb3dSCy Schubert
562*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dmodifymmtimer-16"></a>
563*2b15cb3dSCy SchubertThis is the &ldquo;modify multimedia timer (windows only)&rdquo; option.
564*2b15cb3dSCy Schubert
565*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
566*2b15cb3dSCy Schubert     <ul>
567*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
568*2b15cb3dSCy Schubert</ul>
569*2b15cb3dSCy Schubert
570*2b15cb3dSCy Schubert  <p>Set the Windows Multimedia Timer to highest resolution.  This
571*2b15cb3dSCy Schubertensures the resolution does not change while ntpd is running,
572*2b15cb3dSCy Schubertavoiding timekeeping glitches associated with changes.
573*2b15cb3dSCy Schubert<div class="node">
574*2b15cb3dSCy Schubert<p><hr>
575*2b15cb3dSCy Schubert<a name="ntpd-nice"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-pidfile">ntpd pidfile</a>,
576*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>,
577*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
578*2b15cb3dSCy Schubert<br>
579*2b15cb3dSCy Schubert</div>
580*2b15cb3dSCy Schubert
581*2b15cb3dSCy Schubert<h4 class="subsection">nice option (-N)</h4>
582*2b15cb3dSCy Schubert
583*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dnice-17"></a>
584*2b15cb3dSCy SchubertThis is the &ldquo;run at high priority&rdquo; option.
585*2b15cb3dSCy SchubertTo the extent permitted by the operating system, run
586*2b15cb3dSCy Schubert<code>ntpd</code>
587*2b15cb3dSCy Schubertat the highest priority.
588*2b15cb3dSCy Schubert<div class="node">
589*2b15cb3dSCy Schubert<p><hr>
590*2b15cb3dSCy Schubert<a name="ntpd-pidfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-priority">ntpd priority</a>,
591*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-nice">ntpd nice</a>,
592*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
593*2b15cb3dSCy Schubert<br>
594*2b15cb3dSCy Schubert</div>
595*2b15cb3dSCy Schubert
596*2b15cb3dSCy Schubert<h4 class="subsection">pidfile option (-p)</h4>
597*2b15cb3dSCy Schubert
598*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dpidfile-18"></a>
599*2b15cb3dSCy SchubertThis is the &ldquo;path to the pid file&rdquo; option.
600*2b15cb3dSCy SchubertThis option takes a string argument.
601*2b15cb3dSCy SchubertSpecify the name and path of the file used to record
602*2b15cb3dSCy Schubert<code>ntpd</code>'s
603*2b15cb3dSCy Schubertprocess ID.
604*2b15cb3dSCy SchubertThis is the same operation as the
605*2b15cb3dSCy Schubert<code>pidfile</code> <kbd>pidfile</kbd>
606*2b15cb3dSCy Schubertconfiguration file directive.
607*2b15cb3dSCy Schubert<div class="node">
608*2b15cb3dSCy Schubert<p><hr>
609*2b15cb3dSCy Schubert<a name="ntpd-priority"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-quit">ntpd quit</a>,
610*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-pidfile">ntpd pidfile</a>,
611*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
612*2b15cb3dSCy Schubert<br>
613*2b15cb3dSCy Schubert</div>
614*2b15cb3dSCy Schubert
615*2b15cb3dSCy Schubert<h4 class="subsection">priority option (-P)</h4>
616*2b15cb3dSCy Schubert
617*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dpriority-19"></a>
618*2b15cb3dSCy SchubertThis is the &ldquo;process priority&rdquo; option.
619*2b15cb3dSCy SchubertThis option takes a number argument.
620*2b15cb3dSCy SchubertTo the extent permitted by the operating system, run
621*2b15cb3dSCy Schubert<code>ntpd</code>
622*2b15cb3dSCy Schubertat the specified
623*2b15cb3dSCy Schubert<code>sched_setscheduler(SCHED_FIFO)</code>
624*2b15cb3dSCy Schubertpriority.
625*2b15cb3dSCy Schubert<div class="node">
626*2b15cb3dSCy Schubert<p><hr>
627*2b15cb3dSCy Schubert<a name="ntpd-quit"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-propagationdelay">ntpd propagationdelay</a>,
628*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-priority">ntpd priority</a>,
629*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
630*2b15cb3dSCy Schubert<br>
631*2b15cb3dSCy Schubert</div>
632*2b15cb3dSCy Schubert
633*2b15cb3dSCy Schubert<h4 class="subsection">quit option (-q)</h4>
634*2b15cb3dSCy Schubert
635*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dquit-20"></a>
636*2b15cb3dSCy SchubertThis is the &ldquo;set the time and quit&rdquo; option.
637*2b15cb3dSCy Schubert
638*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
639*2b15cb3dSCy Schubert     <ul>
640*2b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
641*2b15cb3dSCy Schubertsaveconfigquit, wait-sync.
642*2b15cb3dSCy Schubert</ul>
643*2b15cb3dSCy Schubert
644*2b15cb3dSCy Schubert  <p><code>ntpd</code>
645*2b15cb3dSCy Schubertwill not daemonize and will exit after the clock is first
646*2b15cb3dSCy Schubertsynchronized.  This behavior mimics that of the
647*2b15cb3dSCy Schubert<code>ntpdate</code>
648*2b15cb3dSCy Schubertprogram, which will soon be replaced with a shell script.
649*2b15cb3dSCy SchubertThe
650*2b15cb3dSCy Schubert<code>-g</code>
651*2b15cb3dSCy Schubertand
652*2b15cb3dSCy Schubert<code>-x</code>
653*2b15cb3dSCy Schubertoptions can be used with this option.
654*2b15cb3dSCy SchubertNote: The kernel time discipline is disabled with this option.
655*2b15cb3dSCy Schubert<div class="node">
656*2b15cb3dSCy Schubert<p><hr>
657*2b15cb3dSCy Schubert<a name="ntpd-propagationdelay"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>,
658*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-quit">ntpd quit</a>,
659*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
660*2b15cb3dSCy Schubert<br>
661*2b15cb3dSCy Schubert</div>
662*2b15cb3dSCy Schubert
663*2b15cb3dSCy Schubert<h4 class="subsection">propagationdelay option (-r)</h4>
664*2b15cb3dSCy Schubert
665*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dpropagationdelay-21"></a>
666*2b15cb3dSCy SchubertThis is the &ldquo;broadcast/propagation delay&rdquo; option.
667*2b15cb3dSCy SchubertThis option takes a string argument.
668*2b15cb3dSCy 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.
669*2b15cb3dSCy Schubert<div class="node">
670*2b15cb3dSCy Schubert<p><hr>
671*2b15cb3dSCy Schubert<a name="ntpd-saveconfigquit"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-statsdir">ntpd statsdir</a>,
672*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-propagationdelay">ntpd propagationdelay</a>,
673*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
674*2b15cb3dSCy Schubert<br>
675*2b15cb3dSCy Schubert</div>
676*2b15cb3dSCy Schubert
677*2b15cb3dSCy Schubert<h4 class="subsection">saveconfigquit option</h4>
678*2b15cb3dSCy Schubert
679*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dsaveconfigquit-22"></a>
680*2b15cb3dSCy SchubertThis is the &ldquo;save parsed configuration and quit&rdquo; option.
681*2b15cb3dSCy SchubertThis option takes a string argument.
682*2b15cb3dSCy Schubert
683*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
684*2b15cb3dSCy Schubert     <ul>
685*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>SAVECONFIG</code> during the compilation.
686*2b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
687*2b15cb3dSCy Schubertquit, wait-sync.
688*2b15cb3dSCy Schubert</ul>
689*2b15cb3dSCy Schubert
690*2b15cb3dSCy Schubert  <p>Cause <code>ntpd</code> to parse its startup configuration file and save an
691*2b15cb3dSCy Schubertequivalent to the given filename and exit.  This option was
692*2b15cb3dSCy Schubertdesigned for automated testing.
693*2b15cb3dSCy Schubert<div class="node">
694*2b15cb3dSCy Schubert<p><hr>
695*2b15cb3dSCy Schubert<a name="ntpd-statsdir"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-trustedkey">ntpd trustedkey</a>,
696*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>,
697*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
698*2b15cb3dSCy Schubert<br>
699*2b15cb3dSCy Schubert</div>
700*2b15cb3dSCy Schubert
701*2b15cb3dSCy Schubert<h4 class="subsection">statsdir option (-s)</h4>
702*2b15cb3dSCy Schubert
703*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dstatsdir-23"></a>
704*2b15cb3dSCy SchubertThis is the &ldquo;statistics file location&rdquo; option.
705*2b15cb3dSCy SchubertThis option takes a string argument.
706*2b15cb3dSCy SchubertSpecify the directory path for files created by the statistics facility.
707*2b15cb3dSCy SchubertThis is the same operation as the
708*2b15cb3dSCy Schubert<code>statsdir</code> <kbd>statsdir</kbd>
709*2b15cb3dSCy Schubertconfiguration file directive.
710*2b15cb3dSCy Schubert<div class="node">
711*2b15cb3dSCy Schubert<p><hr>
712*2b15cb3dSCy Schubert<a name="ntpd-trustedkey"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-user">ntpd user</a>,
713*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-statsdir">ntpd statsdir</a>,
714*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
715*2b15cb3dSCy Schubert<br>
716*2b15cb3dSCy Schubert</div>
717*2b15cb3dSCy Schubert
718*2b15cb3dSCy Schubert<h4 class="subsection">trustedkey option (-t)</h4>
719*2b15cb3dSCy Schubert
720*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dtrustedkey-24"></a>
721*2b15cb3dSCy SchubertThis is the &ldquo;trusted key number&rdquo; option.
722*2b15cb3dSCy SchubertThis option takes a string argument <span class="file">tkey</span>.
723*2b15cb3dSCy Schubert
724*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
725*2b15cb3dSCy Schubert     <ul>
726*2b15cb3dSCy Schubert<li>may appear an unlimited number of times.
727*2b15cb3dSCy Schubert</ul>
728*2b15cb3dSCy Schubert
729*2b15cb3dSCy Schubert  <p>Add the specified key number to the trusted key list.
730*2b15cb3dSCy Schubert<div class="node">
731*2b15cb3dSCy Schubert<p><hr>
732*2b15cb3dSCy Schubert<a name="ntpd-user"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-updateinterval">ntpd updateinterval</a>,
733*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-trustedkey">ntpd trustedkey</a>,
734*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
735*2b15cb3dSCy Schubert<br>
736*2b15cb3dSCy Schubert</div>
737*2b15cb3dSCy Schubert
738*2b15cb3dSCy Schubert<h4 class="subsection">user option (-u)</h4>
739*2b15cb3dSCy Schubert
740*2b15cb3dSCy Schubert<p><a name="index-ntpd_002duser-25"></a>
741*2b15cb3dSCy SchubertThis is the &ldquo;run as userid (or userid:groupid)&rdquo; option.
742*2b15cb3dSCy SchubertThis option takes a string argument.
743*2b15cb3dSCy Schubert
744*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
745*2b15cb3dSCy Schubert     <ul>
746*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
747*2b15cb3dSCy Schubert</ul>
748*2b15cb3dSCy Schubert
749*2b15cb3dSCy Schubert  <p>Specify a user, and optionally a group, to switch to.
750*2b15cb3dSCy SchubertThis option is only available if the OS supports adjusting the clock
751*2b15cb3dSCy Schubertwithout full root privileges.
752*2b15cb3dSCy SchubertThis option is supported under NetBSD (configure with
753*2b15cb3dSCy Schubert<code>--enable-clockctl</code>) or Linux (configure with
754*2b15cb3dSCy Schubert<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
755*2b15cb3dSCy Schubert<div class="node">
756*2b15cb3dSCy Schubert<p><hr>
757*2b15cb3dSCy Schubert<a name="ntpd-updateinterval"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-wait_002dsync">ntpd wait-sync</a>,
758*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-user">ntpd user</a>,
759*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
760*2b15cb3dSCy Schubert<br>
761*2b15cb3dSCy Schubert</div>
762*2b15cb3dSCy Schubert
763*2b15cb3dSCy Schubert<h4 class="subsection">updateinterval option (-U)</h4>
764*2b15cb3dSCy Schubert
765*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dupdateinterval-26"></a>
766*2b15cb3dSCy SchubertThis is the &ldquo;interval in seconds between scans for new or dropped interfaces&rdquo; option.
767*2b15cb3dSCy SchubertThis option takes a number argument.
768*2b15cb3dSCy SchubertGive the time in seconds between two scans for new or dropped interfaces.
769*2b15cb3dSCy SchubertFor systems with routing socket support the scans will be performed shortly after the interface change
770*2b15cb3dSCy Schuberthas been detected by the system.
771*2b15cb3dSCy SchubertUse 0 to disable scanning. 60 seconds is the minimum time between scans.
772*2b15cb3dSCy Schubert<div class="node">
773*2b15cb3dSCy Schubert<p><hr>
774*2b15cb3dSCy Schubert<a name="ntpd-wait_002dsync"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-slew">ntpd slew</a>,
775*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-updateinterval">ntpd updateinterval</a>,
776*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
777*2b15cb3dSCy Schubert<br>
778*2b15cb3dSCy Schubert</div>
779*2b15cb3dSCy Schubert
780*2b15cb3dSCy Schubert<h4 class="subsection">wait-sync option (-w)</h4>
781*2b15cb3dSCy Schubert
782*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dwait_002dsync-27"></a>
783*2b15cb3dSCy SchubertThis is the &ldquo;seconds to wait for first clock sync&rdquo; option.
784*2b15cb3dSCy SchubertThis option takes a number argument.
785*2b15cb3dSCy Schubert
786*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
787*2b15cb3dSCy Schubert     <ul>
788*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_WORKING_FORK</code> during the compilation.
789*2b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
790*2b15cb3dSCy Schubertnofork, quit, saveconfigquit.
791*2b15cb3dSCy Schubert</ul>
792*2b15cb3dSCy Schubert
793*2b15cb3dSCy Schubert  <p>If greater than zero, alters <code>ntpd</code>'s behavior when forking to
794*2b15cb3dSCy Schubertdaemonize.  Instead of exiting with status 0 immediately after
795*2b15cb3dSCy Schubertthe fork, the parent waits up to the specified number of
796*2b15cb3dSCy Schubertseconds for the child to first synchronize the clock.  The exit
797*2b15cb3dSCy Schubertstatus is zero (success) if the clock was synchronized,
798*2b15cb3dSCy Schubertotherwise it is <code>ETIMEDOUT</code>.
799*2b15cb3dSCy SchubertThis provides the option for a script starting <code>ntpd</code> to easily
800*2b15cb3dSCy Schubertwait for the first set of the clock before proceeding.
801*2b15cb3dSCy Schubert<div class="node">
802*2b15cb3dSCy Schubert<p><hr>
803*2b15cb3dSCy Schubert<a name="ntpd-slew"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-usepcc">ntpd usepcc</a>,
804*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-wait_002dsync">ntpd wait-sync</a>,
805*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
806*2b15cb3dSCy Schubert<br>
807*2b15cb3dSCy Schubert</div>
808*2b15cb3dSCy Schubert
809*2b15cb3dSCy Schubert<h4 class="subsection">slew option (-x)</h4>
810*2b15cb3dSCy Schubert
811*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dslew-28"></a>
812*2b15cb3dSCy SchubertThis is the &ldquo;slew up to 600 seconds&rdquo; option.
813*2b15cb3dSCy 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.
814*2b15cb3dSCy SchubertThis option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually.
815*2b15cb3dSCy 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.
816*2b15cb3dSCy SchubertThus, an adjustment as much as 600 s will take almost 14 days to complete.
817*2b15cb3dSCy SchubertThis option can be used with the
818*2b15cb3dSCy Schubert<code>-g</code>
819*2b15cb3dSCy Schubertand
820*2b15cb3dSCy Schubert<code>-q</code>
821*2b15cb3dSCy Schubertoptions.
822*2b15cb3dSCy SchubertSee the
823*2b15cb3dSCy Schubert<code>tinker</code>
824*2b15cb3dSCy Schubertconfiguration file directive for other options.
825*2b15cb3dSCy SchubertNote: The kernel time discipline is disabled with this option.
826*2b15cb3dSCy Schubert<div class="node">
827*2b15cb3dSCy Schubert<p><hr>
828*2b15cb3dSCy Schubert<a name="ntpd-usepcc"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-pccfreq">ntpd pccfreq</a>,
829*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-slew">ntpd slew</a>,
830*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
831*2b15cb3dSCy Schubert<br>
832*2b15cb3dSCy Schubert</div>
833*2b15cb3dSCy Schubert
834*2b15cb3dSCy Schubert<h4 class="subsection">usepcc option</h4>
835*2b15cb3dSCy Schubert
836*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dusepcc-29"></a>
837*2b15cb3dSCy SchubertThis is the &ldquo;use cpu cycle counter (windows only)&rdquo; option.
838*2b15cb3dSCy Schubert
839*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
840*2b15cb3dSCy Schubert     <ul>
841*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
842*2b15cb3dSCy Schubert</ul>
843*2b15cb3dSCy Schubert
844*2b15cb3dSCy Schubert  <p>Attempt to substitute the CPU counter for <code>QueryPerformanceCounter</code>.
845*2b15cb3dSCy SchubertThe CPU counter and <code>QueryPerformanceCounter</code> are compared, and if
846*2b15cb3dSCy Schubertthey have the same frequency, the CPU counter (RDTSC on x86) is
847*2b15cb3dSCy Schubertused directly, saving the overhead of a system call.
848*2b15cb3dSCy Schubert<div class="node">
849*2b15cb3dSCy Schubert<p><hr>
850*2b15cb3dSCy Schubert<a name="ntpd-pccfreq"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-mdns">ntpd mdns</a>,
851*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-usepcc">ntpd usepcc</a>,
852*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
853*2b15cb3dSCy Schubert<br>
854*2b15cb3dSCy Schubert</div>
855*2b15cb3dSCy Schubert
856*2b15cb3dSCy Schubert<h4 class="subsection">pccfreq option</h4>
857*2b15cb3dSCy Schubert
858*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dpccfreq-30"></a>
859*2b15cb3dSCy SchubertThis is the &ldquo;force cpu cycle counter use (windows only)&rdquo; option.
860*2b15cb3dSCy SchubertThis option takes a string argument.
861*2b15cb3dSCy Schubert
862*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
863*2b15cb3dSCy Schubert     <ul>
864*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
865*2b15cb3dSCy Schubert</ul>
866*2b15cb3dSCy Schubert
867*2b15cb3dSCy Schubert  <p>Force substitution the CPU counter for <code>QueryPerformanceCounter</code>.
868*2b15cb3dSCy SchubertThe CPU counter (RDTSC on x86) is used unconditionally with the
869*2b15cb3dSCy Schubertgiven frequency (in Hz).
870*2b15cb3dSCy Schubert<div class="node">
871*2b15cb3dSCy Schubert<p><hr>
872*2b15cb3dSCy Schubert<a name="ntpd-mdns"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-config">ntpd config</a>,
873*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-pccfreq">ntpd pccfreq</a>,
874*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
875*2b15cb3dSCy Schubert<br>
876*2b15cb3dSCy Schubert</div>
877*2b15cb3dSCy Schubert
878*2b15cb3dSCy Schubert<h4 class="subsection">mdns option (-m)</h4>
879*2b15cb3dSCy Schubert
880*2b15cb3dSCy Schubert<p><a name="index-ntpd_002dmdns-31"></a>
881*2b15cb3dSCy SchubertThis is the &ldquo;register with mdns as a ntp server&rdquo; option.
882*2b15cb3dSCy Schubert
883*2b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
884*2b15cb3dSCy Schubert     <ul>
885*2b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_DNSREGISTRATION</code> during the compilation.
886*2b15cb3dSCy Schubert</ul>
887*2b15cb3dSCy Schubert
888*2b15cb3dSCy Schubert  <p>Registers as an NTP server with the local mDNS server which allows
889*2b15cb3dSCy Schubertthe server to be discovered via mDNS client lookup.
890*2b15cb3dSCy Schubert
891*2b15cb3dSCy Schubert<div class="node">
892*2b15cb3dSCy Schubert<p><hr>
893*2b15cb3dSCy Schubert<a name="ntpd-config"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-exit-status">ntpd exit status</a>,
894*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-mdns">ntpd mdns</a>,
895*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
896*2b15cb3dSCy Schubert<br>
897*2b15cb3dSCy Schubert</div>
898*2b15cb3dSCy Schubert
899*2b15cb3dSCy Schubert<h4 class="subsection">presetting/configuring ntpd</h4>
900*2b15cb3dSCy Schubert
901*2b15cb3dSCy Schubert<p>Any option that is not marked as <i>not presettable</i> may be preset by
902*2b15cb3dSCy 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
903*2b15cb3dSCy Schubertthe options listed above in upper case and segmented with underscores.
904*2b15cb3dSCy SchubertThe <code>NTPD</code> variable will be tokenized and parsed like
905*2b15cb3dSCy Schubertthe command line.  The remaining variables are tested for existence and their
906*2b15cb3dSCy Schubertvalues are treated like option arguments.
907*2b15cb3dSCy Schubert
908*2b15cb3dSCy Schubert  <p>The command line options relating to configuration and/or usage help are:
909*2b15cb3dSCy Schubert
910*2b15cb3dSCy Schubert<h5 class="subsubheading">version (-)</h5>
911*2b15cb3dSCy Schubert
912*2b15cb3dSCy Schubert<p>Print the program version to standard out, optionally with licensing
913*2b15cb3dSCy Schubertinformation, then exit 0.  The optional argument specifies how much licensing
914*2b15cb3dSCy Schubertdetail to provide.  The default is to print just the version.  The licensing infomation may be selected with an option argument.
915*2b15cb3dSCy SchubertOnly the first letter of the argument is examined:
916*2b15cb3dSCy Schubert
917*2b15cb3dSCy Schubert     <dl>
918*2b15cb3dSCy Schubert<dt><span class="samp">version</span><dd>Only print the version.  This is the default.
919*2b15cb3dSCy Schubert<br><dt><span class="samp">copyright</span><dd>Name the copyright usage licensing terms.
920*2b15cb3dSCy Schubert<br><dt><span class="samp">verbose</span><dd>Print the full copyright usage licensing terms.
921*2b15cb3dSCy Schubert</dl>
922*2b15cb3dSCy Schubert
923*2b15cb3dSCy Schubert<div class="node">
924*2b15cb3dSCy Schubert<p><hr>
925*2b15cb3dSCy Schubert<a name="ntpd-exit-status"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Usage">ntpd Usage</a>,
926*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-config">ntpd config</a>,
927*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
928*2b15cb3dSCy Schubert<br>
929*2b15cb3dSCy Schubert</div>
930*2b15cb3dSCy Schubert
931*2b15cb3dSCy Schubert<h4 class="subsection">ntpd exit status</h4>
932*2b15cb3dSCy Schubert
933*2b15cb3dSCy Schubert<p>One of the following exit values will be returned:
934*2b15cb3dSCy Schubert     <dl>
935*2b15cb3dSCy Schubert<dt><span class="samp">0 (EXIT_SUCCESS)</span><dd>Successful program execution.
936*2b15cb3dSCy Schubert<br><dt><span class="samp">1 (EXIT_FAILURE)</span><dd>The operation failed or the command syntax was not valid.
937*2b15cb3dSCy Schubert</dl>
938*2b15cb3dSCy Schubert  <div class="node">
939*2b15cb3dSCy Schubert<p><hr>
940*2b15cb3dSCy Schubert<a name="ntpd-Usage"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Files">ntpd Files</a>,
941*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-exit-status">ntpd exit status</a>,
942*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
943*2b15cb3dSCy Schubert<br>
944*2b15cb3dSCy Schubert</div>
945*2b15cb3dSCy Schubert
946*2b15cb3dSCy Schubert<h4 class="subsection">ntpd Usage</h4>
947*2b15cb3dSCy Schubert
948*2b15cb3dSCy Schubert<div class="node">
949*2b15cb3dSCy Schubert<p><hr>
950*2b15cb3dSCy Schubert<a name="ntpd-Files"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-See-Also">ntpd See Also</a>,
951*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-Usage">ntpd Usage</a>,
952*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
953*2b15cb3dSCy Schubert<br>
954*2b15cb3dSCy Schubert</div>
955*2b15cb3dSCy Schubert
956*2b15cb3dSCy Schubert<h4 class="subsection">ntpd Files</h4>
957*2b15cb3dSCy Schubert
958*2b15cb3dSCy Schubert<div class="node">
959*2b15cb3dSCy Schubert<p><hr>
960*2b15cb3dSCy Schubert<a name="ntpd-See-Also"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Bugs">ntpd Bugs</a>,
961*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-Files">ntpd Files</a>,
962*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
963*2b15cb3dSCy Schubert<br>
964*2b15cb3dSCy Schubert</div>
965*2b15cb3dSCy Schubert
966*2b15cb3dSCy Schubert<h4 class="subsection">ntpd See Also</h4>
967*2b15cb3dSCy Schubert
968*2b15cb3dSCy Schubert<div class="node">
969*2b15cb3dSCy Schubert<p><hr>
970*2b15cb3dSCy Schubert<a name="ntpd-Bugs"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Notes">ntpd Notes</a>,
971*2b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-See-Also">ntpd See Also</a>,
972*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
973*2b15cb3dSCy Schubert<br>
974*2b15cb3dSCy Schubert</div>
975*2b15cb3dSCy Schubert
976*2b15cb3dSCy Schubert<h4 class="subsection">ntpd Bugs</h4>
977*2b15cb3dSCy Schubert
978*2b15cb3dSCy Schubert<div class="node">
979*2b15cb3dSCy Schubert<p><hr>
980*2b15cb3dSCy Schubert<a name="ntpd-Notes"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-Bugs">ntpd Bugs</a>,
981*2b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
982*2b15cb3dSCy Schubert<br>
983*2b15cb3dSCy Schubert</div>
984*2b15cb3dSCy Schubert
985*2b15cb3dSCy Schubert<h4 class="subsection">ntpd Notes</h4>
986*2b15cb3dSCy Schubert
987*2b15cb3dSCy Schubert<div class="node">
988*2b15cb3dSCy Schubert<p><hr>
989*2b15cb3dSCy Schubert<a name="Usage"></a>
990*2b15cb3dSCy Schubert<br>
991*2b15cb3dSCy Schubert</div>
992*2b15cb3dSCy Schubert
993*2b15cb3dSCy Schubert<!-- node-name,  next,  previous,  up -->
994*2b15cb3dSCy Schubert<h3 class="section">Usage</h3>
995*2b15cb3dSCy Schubert
996