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222b15cb3dSCy Schubert<h1 class="settitle">ntpd: Network Time Protocol (NTP) Daemon User's Manual</h1>
232b15cb3dSCy Schubert<div class="node">
242b15cb3dSCy Schubert<p><hr>
252b15cb3dSCy Schubert<a name="Top"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Description">ntpd Description</a>,
262b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#dir">(dir)</a>,
272b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#dir">(dir)</a>
282b15cb3dSCy Schubert<br>
292b15cb3dSCy Schubert</div>
302b15cb3dSCy Schubert
312b15cb3dSCy Schubert<h2 class="unnumbered">ntpd: Network Time Protocol (NTP) Daemon User Manual</h2>
322b15cb3dSCy Schubert
332b15cb3dSCy Schubert<p>The <code>ntpd</code> program is an operating system daemon that synchronizes the
342b15cb3dSCy Schubertsystem clock to remote NTP time servers or local reference clocks.
352b15cb3dSCy SchubertIt is a complete implementation of NTP version 4 defined by RFC-5905, but
362b15cb3dSCy Schubertalso retains compatible with version 3 defined by RFC-1305 and versions
372b15cb3dSCy Schubert1 and 2, defined by RFC-1059 and RFC-1119, respectively.
382b15cb3dSCy SchubertThe program can operate in any of several modes, including client/server,
392b15cb3dSCy Schubertsymmetric and broadcast modes, and with both symmetric-key and public-key
402b15cb3dSCy Schubertcryptography.
412b15cb3dSCy Schubert
42*a25439b6SCy Schubert  <p>This document applies to version 4.2.8p2 of <code>ntpd</code>.
432b15cb3dSCy Schubert
442b15cb3dSCy Schubert<ul class="menu">
452b15cb3dSCy Schubert<li><a accesskey="1" href="#ntpd-Description">ntpd Description</a>:             Description
462b15cb3dSCy Schubert<li><a accesskey="2" href="#ntpd-Invocation">ntpd Invocation</a>: 		Invoking ntpd
472b15cb3dSCy Schubert<li><a accesskey="3" href="#Usage">Usage</a>:                        Usage
482b15cb3dSCy Schubert</ul>
492b15cb3dSCy Schubert
502b15cb3dSCy Schubert<div class="node">
512b15cb3dSCy Schubert<p><hr>
522b15cb3dSCy Schubert<a name="ntpd-Description"></a>
532b15cb3dSCy Schubert<br>
542b15cb3dSCy Schubert</div>
552b15cb3dSCy Schubert
562b15cb3dSCy Schubert<!-- node-name,  next,  previous,  up -->
572b15cb3dSCy Schubert<h3 class="section">Description</h3>
582b15cb3dSCy Schubert
592b15cb3dSCy Schubert<p>The <code>ntpd</code> program ordinarily requires
602b15cb3dSCy Schuberta configuration file described at <a href="#ntp_002econf">ntp.conf</a>.
612b15cb3dSCy SchubertThis configuration file contains configuration commands described on
622b15cb3dSCy Schubertthe pages listed above.
632b15cb3dSCy SchubertHowever a client can discover remote servers and configure them
642b15cb3dSCy Schubertautomatically.
652b15cb3dSCy SchubertThis makes it possible to deploy a fleet of workstations without
662b15cb3dSCy Schubertspecifying configuration details specific to the local environment.
672b15cb3dSCy Schubert
682b15cb3dSCy Schubert  <p>The <code>ntpd</code> program normally operates continuously while adjusting the
692b15cb3dSCy Schubertsystem time and frequency, but in some cases this might not be
702b15cb3dSCy Schubertpractical.
712b15cb3dSCy SchubertWith the <code>-q</code> option <code>ntpd</code> operates as in continuous mode, but
722b15cb3dSCy Schubertexits just after setting the clock for the first time.
732b15cb3dSCy SchubertMost applications will probably want to specify the <code>iburst</code>
742b15cb3dSCy Schubertoption with the <code>server</code> command.
752b15cb3dSCy SchubertWith this option an initial volley of messages is exchanged to
762b15cb3dSCy Schubertgroom the data and set the clock in about ten seconds' time.
772b15cb3dSCy SchubertIf nothing is heard after a few minutes' time,
782b15cb3dSCy Schubertthe daemon times out and exits without setting the clock.
792b15cb3dSCy Schubert
802b15cb3dSCy Schubert<div class="node">
812b15cb3dSCy Schubert<p><hr>
822b15cb3dSCy Schubert<a name="ntpd-Invocation"></a>
832b15cb3dSCy Schubert<br>
842b15cb3dSCy Schubert</div>
852b15cb3dSCy Schubert
862b15cb3dSCy Schubert<h3 class="section">Invoking ntpd</h3>
872b15cb3dSCy Schubert
882b15cb3dSCy Schubert<p><a name="index-ntpd-1"></a><a name="index-NTP-daemon-program-2"></a>
892b15cb3dSCy Schubert
902b15cb3dSCy Schubert  <p>The
912b15cb3dSCy Schubert<code>ntpd</code>
922b15cb3dSCy Schubertutility is an operating system daemon which sets
932b15cb3dSCy Schubertand maintains the system time of day in synchronism with Internet
942b15cb3dSCy Schubertstandard time servers.
952b15cb3dSCy SchubertIt is a complete implementation of the
962b15cb3dSCy SchubertNetwork Time Protocol (NTP) version 4, as defined by RFC-5905,
972b15cb3dSCy Schubertbut also retains compatibility with
982b15cb3dSCy Schubertversion 3, as defined by RFC-1305, and versions 1
992b15cb3dSCy Schubertand 2, as defined by RFC-1059 and RFC-1119, respectively.
1002b15cb3dSCy Schubert
1012b15cb3dSCy Schubert  <p>The
1022b15cb3dSCy Schubert<code>ntpd</code>
1032b15cb3dSCy Schubertutility does most computations in 64-bit floating point
1042b15cb3dSCy Schubertarithmetic and does relatively clumsy 64-bit fixed point operations
1052b15cb3dSCy Schubertonly when necessary to preserve the ultimate precision, about 232
1062b15cb3dSCy Schubertpicoseconds.
1072b15cb3dSCy SchubertWhile the ultimate precision is not achievable with
1082b15cb3dSCy Schubertordinary workstations and networks of today, it may be required
1092b15cb3dSCy Schubertwith future gigahertz CPU clocks and gigabit LANs.
1102b15cb3dSCy Schubert
1112b15cb3dSCy Schubert  <p>Ordinarily,
1122b15cb3dSCy Schubert<code>ntpd</code>
1132b15cb3dSCy Schubertreads the
1142b15cb3dSCy Schubert<code>ntp.conf(5)</code>
1152b15cb3dSCy Schubertconfiguration file at startup time in order to determine the
1162b15cb3dSCy Schubertsynchronization sources and operating modes.
1172b15cb3dSCy SchubertIt is also possible to
1182b15cb3dSCy Schubertspecify a working, although limited, configuration entirely on the
1192b15cb3dSCy Schubertcommand line, obviating the need for a configuration file.
1202b15cb3dSCy SchubertThis may
1212b15cb3dSCy Schubertbe particularly useful when the local host is to be configured as a
1222b15cb3dSCy Schubertbroadcast/multicast client, with all peers being determined by
1232b15cb3dSCy Schubertlistening to broadcasts at run time.
1242b15cb3dSCy Schubert
1252b15cb3dSCy Schubert  <p>If NetInfo support is built into
1262b15cb3dSCy Schubert<code>ntpd</code>
1272b15cb3dSCy Schubertthen
1282b15cb3dSCy Schubert<code>ntpd</code>
1292b15cb3dSCy Schubertwill attempt to read its configuration from the
1302b15cb3dSCy SchubertNetInfo if the default
1312b15cb3dSCy Schubert<code>ntp.conf(5)</code>
1322b15cb3dSCy Schubertfile cannot be read and no file is
1332b15cb3dSCy Schubertspecified by the
1342b15cb3dSCy Schubert<code>-c</code>
1352b15cb3dSCy Schubertoption.
1362b15cb3dSCy Schubert
1372b15cb3dSCy Schubert  <p>Various internal
1382b15cb3dSCy Schubert<code>ntpd</code>
1392b15cb3dSCy Schubertvariables can be displayed and
1402b15cb3dSCy Schubertconfiguration options altered while the
1412b15cb3dSCy Schubert<code>ntpd</code>
1422b15cb3dSCy Schubertis running
1432b15cb3dSCy Schubertusing the
1442b15cb3dSCy Schubert<code>ntpq(1ntpqmdoc)</code>
1452b15cb3dSCy Schubertand
1462b15cb3dSCy Schubert<code>ntpdc(1ntpdcmdoc)</code>
1472b15cb3dSCy Schubertutility programs.
1482b15cb3dSCy Schubert
1492b15cb3dSCy Schubert  <p>When
1502b15cb3dSCy Schubert<code>ntpd</code>
1512b15cb3dSCy Schubertstarts it looks at the value of
1522b15cb3dSCy Schubert<code>umask(2)</code>,
1532b15cb3dSCy Schubertand if zero
1542b15cb3dSCy Schubert<code>ntpd</code>
1552b15cb3dSCy Schubertwill set the
1562b15cb3dSCy Schubert<code>umask(2)</code>
1572b15cb3dSCy Schubertto 022.
1582b15cb3dSCy Schubert
1592b15cb3dSCy Schubert  <p>This section was generated by <strong>AutoGen</strong>,
1602b15cb3dSCy Schubertusing the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntpd</code> program.
1612b15cb3dSCy SchubertThis software is released under the NTP license, &lt;http://ntp.org/license&gt;.
1622b15cb3dSCy Schubert
1632b15cb3dSCy Schubert<ul class="menu">
1642b15cb3dSCy Schubert<li><a accesskey="1" href="#ntpd-usage">ntpd usage</a>:                   ntpd help/usage (<span class="option">--help</span>)
1652b15cb3dSCy Schubert<li><a accesskey="2" href="#ntpd-ipv4">ntpd ipv4</a>:                    ipv4 option (-4)
1662b15cb3dSCy Schubert<li><a accesskey="3" href="#ntpd-ipv6">ntpd ipv6</a>:                    ipv6 option (-6)
1672b15cb3dSCy Schubert<li><a accesskey="4" href="#ntpd-authreq">ntpd authreq</a>:                 authreq option (-a)
1682b15cb3dSCy Schubert<li><a accesskey="5" href="#ntpd-authnoreq">ntpd authnoreq</a>:               authnoreq option (-A)
1692b15cb3dSCy Schubert<li><a accesskey="6" href="#ntpd-configfile">ntpd configfile</a>:              configfile option (-c)
1702b15cb3dSCy Schubert<li><a accesskey="7" href="#ntpd-driftfile">ntpd driftfile</a>:               driftfile option (-f)
1712b15cb3dSCy Schubert<li><a accesskey="8" href="#ntpd-panicgate">ntpd panicgate</a>:               panicgate option (-g)
172*a25439b6SCy Schubert<li><a accesskey="9" href="#ntpd-force_002dstep_002donce">ntpd force-step-once</a>:         force-step-once option (-G)
173*a25439b6SCy Schubert<li><a href="#ntpd-jaildir">ntpd jaildir</a>:                 jaildir option (-i)
1742b15cb3dSCy Schubert<li><a href="#ntpd-interface">ntpd interface</a>:               interface option (-I)
1752b15cb3dSCy Schubert<li><a href="#ntpd-keyfile">ntpd keyfile</a>:                 keyfile option (-k)
1762b15cb3dSCy Schubert<li><a href="#ntpd-logfile">ntpd logfile</a>:                 logfile option (-l)
1772b15cb3dSCy Schubert<li><a href="#ntpd-novirtualips">ntpd novirtualips</a>:            novirtualips option (-L)
1782b15cb3dSCy Schubert<li><a href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>:           modifymmtimer option (-M)
1792b15cb3dSCy Schubert<li><a href="#ntpd-nice">ntpd nice</a>:                    nice option (-N)
1802b15cb3dSCy Schubert<li><a href="#ntpd-pidfile">ntpd pidfile</a>:                 pidfile option (-p)
1812b15cb3dSCy Schubert<li><a href="#ntpd-priority">ntpd priority</a>:                priority option (-P)
1822b15cb3dSCy Schubert<li><a href="#ntpd-quit">ntpd quit</a>:                    quit option (-q)
1832b15cb3dSCy Schubert<li><a href="#ntpd-propagationdelay">ntpd propagationdelay</a>:        propagationdelay option (-r)
1842b15cb3dSCy Schubert<li><a href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>:          saveconfigquit option
1852b15cb3dSCy Schubert<li><a href="#ntpd-statsdir">ntpd statsdir</a>:                statsdir option (-s)
1862b15cb3dSCy Schubert<li><a href="#ntpd-trustedkey">ntpd trustedkey</a>:              trustedkey option (-t)
1872b15cb3dSCy Schubert<li><a href="#ntpd-user">ntpd user</a>:                    user option (-u)
1882b15cb3dSCy Schubert<li><a href="#ntpd-updateinterval">ntpd updateinterval</a>:          updateinterval option (-U)
1892b15cb3dSCy Schubert<li><a href="#ntpd-wait_002dsync">ntpd wait-sync</a>:               wait-sync option (-w)
1902b15cb3dSCy Schubert<li><a href="#ntpd-slew">ntpd slew</a>:                    slew option (-x)
1912b15cb3dSCy Schubert<li><a href="#ntpd-usepcc">ntpd usepcc</a>:                  usepcc option
1922b15cb3dSCy Schubert<li><a href="#ntpd-pccfreq">ntpd pccfreq</a>:                 pccfreq option
1932b15cb3dSCy Schubert<li><a href="#ntpd-mdns">ntpd mdns</a>:                    mdns option (-m)
1942b15cb3dSCy Schubert<li><a href="#ntpd-config">ntpd config</a>:                  presetting/configuring ntpd
1952b15cb3dSCy Schubert<li><a href="#ntpd-exit-status">ntpd exit status</a>:             exit status
1962b15cb3dSCy Schubert<li><a href="#ntpd-Usage">ntpd Usage</a>:                   Usage
1972b15cb3dSCy Schubert<li><a href="#ntpd-Files">ntpd Files</a>:                   Files
1982b15cb3dSCy Schubert<li><a href="#ntpd-See-Also">ntpd See Also</a>:                See Also
1992b15cb3dSCy Schubert<li><a href="#ntpd-Bugs">ntpd Bugs</a>:                    Bugs
2002b15cb3dSCy Schubert<li><a href="#ntpd-Notes">ntpd Notes</a>:                   Notes
2012b15cb3dSCy Schubert</ul>
2022b15cb3dSCy Schubert
2032b15cb3dSCy Schubert<div class="node">
2042b15cb3dSCy Schubert<p><hr>
2052b15cb3dSCy Schubert<a name="ntpd-usage"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-ipv4">ntpd ipv4</a>,
2062b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
2072b15cb3dSCy Schubert<br>
2082b15cb3dSCy Schubert</div>
2092b15cb3dSCy Schubert
2102b15cb3dSCy Schubert<h4 class="subsection">ntpd help/usage (<span class="option">--help</span>)</h4>
2112b15cb3dSCy Schubert
2122b15cb3dSCy Schubert<p><a name="index-ntpd-help-3"></a>
2132b15cb3dSCy SchubertThis is the automatically generated usage text for ntpd.
2142b15cb3dSCy Schubert
2152b15cb3dSCy Schubert  <p>The text printed is the same whether selected with the <code>help</code> option
2162b15cb3dSCy 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
2172b15cb3dSCy Schubertthe usage text by passing it through a pager program.
2182b15cb3dSCy Schubert<code>more-help</code> is disabled on platforms without a working
2192b15cb3dSCy Schubert<code>fork(2)</code> function.  The <code>PAGER</code> environment variable is
2202b15cb3dSCy Schubertused to select the program, defaulting to <span class="file">more</span>.  Both will exit
2212b15cb3dSCy Schubertwith a status code of 0.
2222b15cb3dSCy Schubert
223*a25439b6SCy Schubert<pre class="example">ntpd - NTP daemon program - Ver. 4.2.8p2-RC3
2242b15cb3dSCy SchubertUsage:  ntpd [ -&lt;flag&gt; [&lt;val&gt;] | --&lt;name&gt;[{=| }&lt;val&gt;] ]... \
2252b15cb3dSCy Schubert                [ &lt;server1&gt; ... &lt;serverN&gt; ]
2262b15cb3dSCy Schubert  Flg Arg Option-Name    Description
2272b15cb3dSCy Schubert   -4 no  ipv4           Force IPv4 DNS name resolution
2282b15cb3dSCy Schubert                                - prohibits the option 'ipv6'
2292b15cb3dSCy Schubert   -6 no  ipv6           Force IPv6 DNS name resolution
2302b15cb3dSCy Schubert                                - prohibits the option 'ipv4'
2312b15cb3dSCy Schubert   -a no  authreq        Require crypto authentication
2322b15cb3dSCy Schubert                                - prohibits the option 'authnoreq'
2332b15cb3dSCy Schubert   -A no  authnoreq      Do not require crypto authentication
2342b15cb3dSCy Schubert                                - prohibits the option 'authreq'
2352b15cb3dSCy Schubert   -b no  bcastsync      Allow us to sync to broadcast servers
2362b15cb3dSCy Schubert   -c Str configfile     configuration file name
2372b15cb3dSCy Schubert   -d no  debug-level    Increase debug verbosity level
2382b15cb3dSCy Schubert                                - may appear multiple times
2392b15cb3dSCy Schubert   -D Num set-debug-level Set the debug verbosity level
2402b15cb3dSCy Schubert                                - may appear multiple times
2412b15cb3dSCy Schubert   -f Str driftfile      frequency drift file name
2422b15cb3dSCy Schubert   -g no  panicgate      Allow the first adjustment to be Big
2432b15cb3dSCy Schubert                                - may appear multiple times
244*a25439b6SCy Schubert   -G no  force-step-once Step any initial offset correction.
2452b15cb3dSCy Schubert   -i Str jaildir        Jail directory
2462b15cb3dSCy Schubert   -I Str interface      Listen on an interface name or address
2472b15cb3dSCy Schubert                                - may appear multiple times
2482b15cb3dSCy Schubert   -k Str keyfile        path to symmetric keys
2492b15cb3dSCy Schubert   -l Str logfile        path to the log file
2502b15cb3dSCy Schubert   -L no  novirtualips   Do not listen to virtual interfaces
2512b15cb3dSCy Schubert   -n no  nofork         Do not fork
2522b15cb3dSCy Schubert                                - prohibits the option 'wait-sync'
2532b15cb3dSCy Schubert   -N no  nice           Run at high priority
2542b15cb3dSCy Schubert   -p Str pidfile        path to the PID file
2552b15cb3dSCy Schubert   -P Num priority       Process priority
2562b15cb3dSCy Schubert   -q no  quit           Set the time and quit
2572b15cb3dSCy Schubert                                - prohibits these options:
2582b15cb3dSCy Schubert                                saveconfigquit
2592b15cb3dSCy Schubert                                wait-sync
2602b15cb3dSCy Schubert   -r Str propagationdelay Broadcast/propagation delay
2612b15cb3dSCy Schubert      Str saveconfigquit Save parsed configuration and quit
2622b15cb3dSCy Schubert                                - prohibits these options:
2632b15cb3dSCy Schubert                                quit
2642b15cb3dSCy Schubert                                wait-sync
2652b15cb3dSCy Schubert   -s Str statsdir       Statistics file location
2662b15cb3dSCy Schubert   -t Str trustedkey     Trusted key number
2672b15cb3dSCy Schubert                                - may appear multiple times
2682b15cb3dSCy Schubert   -u Str user           Run as userid (or userid:groupid)
2692b15cb3dSCy Schubert   -U Num updateinterval interval in seconds between scans for new or dropped interfaces
2702b15cb3dSCy Schubert      Str var            make ARG an ntp variable (RW)
2712b15cb3dSCy Schubert                                - may appear multiple times
2722b15cb3dSCy Schubert      Str dvar           make ARG an ntp variable (RW|DEF)
2732b15cb3dSCy Schubert                                - may appear multiple times
2742b15cb3dSCy Schubert   -w Num wait-sync      Seconds to wait for first clock sync
2752b15cb3dSCy Schubert                                - prohibits these options:
2762b15cb3dSCy Schubert                                nofork
2772b15cb3dSCy Schubert                                quit
2782b15cb3dSCy Schubert                                saveconfigquit
2792b15cb3dSCy Schubert   -x no  slew           Slew up to 600 seconds
2802b15cb3dSCy Schubert      opt version        output version information and exit
2812b15cb3dSCy Schubert   -? no  help           display extended usage information and exit
2822b15cb3dSCy Schubert   -! no  more-help      extended usage information passed thru pager
2832b15cb3dSCy Schubert
2842b15cb3dSCy SchubertOptions are specified by doubled hyphens and their name or by a single
2852b15cb3dSCy Schuberthyphen and the flag character.
2862b15cb3dSCy Schubert
2872b15cb3dSCy Schubert
2882b15cb3dSCy SchubertThe following option preset mechanisms are supported:
2892b15cb3dSCy Schubert - examining environment variables named NTPD_*
2902b15cb3dSCy Schubert
2912b15cb3dSCy SchubertPlease send bug reports to:  &lt;http://bugs.ntp.org, bugs@ntp.org&gt;
2922b15cb3dSCy Schubert</pre>
2932b15cb3dSCy Schubert  <div class="node">
2942b15cb3dSCy Schubert<p><hr>
2952b15cb3dSCy Schubert<a name="ntpd-ipv4"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-ipv6">ntpd ipv6</a>,
2962b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-usage">ntpd usage</a>,
2972b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
2982b15cb3dSCy Schubert<br>
2992b15cb3dSCy Schubert</div>
3002b15cb3dSCy Schubert
3012b15cb3dSCy Schubert<h4 class="subsection">ipv4 option (-4)</h4>
3022b15cb3dSCy Schubert
3032b15cb3dSCy Schubert<p><a name="index-ntpd_002dipv4-4"></a>
3042b15cb3dSCy SchubertThis is the &ldquo;force ipv4 dns name resolution&rdquo; option.
3052b15cb3dSCy Schubert
3062b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
3072b15cb3dSCy Schubert     <ul>
3082b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
3092b15cb3dSCy Schubertipv6.
3102b15cb3dSCy Schubert</ul>
3112b15cb3dSCy Schubert
3122b15cb3dSCy Schubert  <p>Force DNS resolution of following host names on the command line
3132b15cb3dSCy Schubertto the IPv4 namespace.
3142b15cb3dSCy Schubert<div class="node">
3152b15cb3dSCy Schubert<p><hr>
3162b15cb3dSCy Schubert<a name="ntpd-ipv6"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-authreq">ntpd authreq</a>,
3172b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-ipv4">ntpd ipv4</a>,
3182b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
3192b15cb3dSCy Schubert<br>
3202b15cb3dSCy Schubert</div>
3212b15cb3dSCy Schubert
3222b15cb3dSCy Schubert<h4 class="subsection">ipv6 option (-6)</h4>
3232b15cb3dSCy Schubert
3242b15cb3dSCy Schubert<p><a name="index-ntpd_002dipv6-5"></a>
3252b15cb3dSCy SchubertThis is the &ldquo;force ipv6 dns name resolution&rdquo; option.
3262b15cb3dSCy Schubert
3272b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
3282b15cb3dSCy Schubert     <ul>
3292b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
3302b15cb3dSCy Schubertipv4.
3312b15cb3dSCy Schubert</ul>
3322b15cb3dSCy Schubert
3332b15cb3dSCy Schubert  <p>Force DNS resolution of following host names on the command line
3342b15cb3dSCy Schubertto the IPv6 namespace.
3352b15cb3dSCy Schubert<div class="node">
3362b15cb3dSCy Schubert<p><hr>
3372b15cb3dSCy Schubert<a name="ntpd-authreq"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-authnoreq">ntpd authnoreq</a>,
3382b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-ipv6">ntpd ipv6</a>,
3392b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
3402b15cb3dSCy Schubert<br>
3412b15cb3dSCy Schubert</div>
3422b15cb3dSCy Schubert
3432b15cb3dSCy Schubert<h4 class="subsection">authreq option (-a)</h4>
3442b15cb3dSCy Schubert
3452b15cb3dSCy Schubert<p><a name="index-ntpd_002dauthreq-6"></a>
3462b15cb3dSCy SchubertThis is the &ldquo;require crypto authentication&rdquo; option.
3472b15cb3dSCy Schubert
3482b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
3492b15cb3dSCy Schubert     <ul>
3502b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
3512b15cb3dSCy Schubertauthnoreq.
3522b15cb3dSCy Schubert</ul>
3532b15cb3dSCy Schubert
3542b15cb3dSCy Schubert  <p>Require cryptographic authentication for broadcast client,
3552b15cb3dSCy Schubertmulticast client and symmetric passive associations.
3562b15cb3dSCy SchubertThis is the default.
3572b15cb3dSCy Schubert<div class="node">
3582b15cb3dSCy Schubert<p><hr>
3592b15cb3dSCy Schubert<a name="ntpd-authnoreq"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-configfile">ntpd configfile</a>,
3602b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-authreq">ntpd authreq</a>,
3612b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
3622b15cb3dSCy Schubert<br>
3632b15cb3dSCy Schubert</div>
3642b15cb3dSCy Schubert
3652b15cb3dSCy Schubert<h4 class="subsection">authnoreq option (-A)</h4>
3662b15cb3dSCy Schubert
3672b15cb3dSCy Schubert<p><a name="index-ntpd_002dauthnoreq-7"></a>
3682b15cb3dSCy SchubertThis is the &ldquo;do not require crypto authentication&rdquo; option.
3692b15cb3dSCy Schubert
3702b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
3712b15cb3dSCy Schubert     <ul>
3722b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
3732b15cb3dSCy Schubertauthreq.
3742b15cb3dSCy Schubert</ul>
3752b15cb3dSCy Schubert
3762b15cb3dSCy Schubert  <p>Do not require cryptographic authentication for broadcast client,
3772b15cb3dSCy Schubertmulticast client and symmetric passive associations.
3782b15cb3dSCy SchubertThis is almost never a good idea.
3792b15cb3dSCy Schubert<div class="node">
3802b15cb3dSCy Schubert<p><hr>
3812b15cb3dSCy Schubert<a name="ntpd-configfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-driftfile">ntpd driftfile</a>,
3822b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-authnoreq">ntpd authnoreq</a>,
3832b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
3842b15cb3dSCy Schubert<br>
3852b15cb3dSCy Schubert</div>
3862b15cb3dSCy Schubert
3872b15cb3dSCy Schubert<h4 class="subsection">configfile option (-c)</h4>
3882b15cb3dSCy Schubert
3892b15cb3dSCy Schubert<p><a name="index-ntpd_002dconfigfile-8"></a>
3902b15cb3dSCy SchubertThis is the &ldquo;configuration file name&rdquo; option.
3912b15cb3dSCy SchubertThis option takes a string argument.
3922b15cb3dSCy SchubertThe name and path of the configuration file,
3932b15cb3dSCy Schubert<span class="file">/etc/ntp.conf</span>
3942b15cb3dSCy Schubertby default.
3952b15cb3dSCy Schubert<div class="node">
3962b15cb3dSCy Schubert<p><hr>
3972b15cb3dSCy Schubert<a name="ntpd-driftfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-panicgate">ntpd panicgate</a>,
3982b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-configfile">ntpd configfile</a>,
3992b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
4002b15cb3dSCy Schubert<br>
4012b15cb3dSCy Schubert</div>
4022b15cb3dSCy Schubert
4032b15cb3dSCy Schubert<h4 class="subsection">driftfile option (-f)</h4>
4042b15cb3dSCy Schubert
4052b15cb3dSCy Schubert<p><a name="index-ntpd_002ddriftfile-9"></a>
4062b15cb3dSCy SchubertThis is the &ldquo;frequency drift file name&rdquo; option.
4072b15cb3dSCy SchubertThis option takes a string argument.
4082b15cb3dSCy SchubertThe name and path of the frequency file,
4092b15cb3dSCy Schubert<span class="file">/etc/ntp.drift</span>
4102b15cb3dSCy Schubertby default.
4112b15cb3dSCy SchubertThis is the same operation as the
4122b15cb3dSCy Schubert<code>driftfile</code> <kbd>driftfile</kbd>
4132b15cb3dSCy Schubertconfiguration specification in the
4142b15cb3dSCy Schubert<span class="file">/etc/ntp.conf</span>
4152b15cb3dSCy Schubertfile.
4162b15cb3dSCy Schubert<div class="node">
4172b15cb3dSCy Schubert<p><hr>
418*a25439b6SCy Schubert<a name="ntpd-panicgate"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-force_002dstep_002donce">ntpd force-step-once</a>,
4192b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-driftfile">ntpd driftfile</a>,
4202b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
4212b15cb3dSCy Schubert<br>
4222b15cb3dSCy Schubert</div>
4232b15cb3dSCy Schubert
4242b15cb3dSCy Schubert<h4 class="subsection">panicgate option (-g)</h4>
4252b15cb3dSCy Schubert
4262b15cb3dSCy Schubert<p><a name="index-ntpd_002dpanicgate-10"></a>
4272b15cb3dSCy SchubertThis is the &ldquo;allow the first adjustment to be big&rdquo; option.
4282b15cb3dSCy Schubert
4292b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
4302b15cb3dSCy Schubert     <ul>
4312b15cb3dSCy Schubert<li>may appear an unlimited number of times.
4322b15cb3dSCy Schubert</ul>
4332b15cb3dSCy Schubert
4342b15cb3dSCy Schubert  <p>Normally,
4352b15cb3dSCy Schubert<code>ntpd</code>
4362b15cb3dSCy 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,
4372b15cb3dSCy Schubert<code>ntpd</code>
4382b15cb3dSCy Schubertwill exit with a message to the system log. This option can be used with the
4392b15cb3dSCy Schubert<code>-q</code>
4402b15cb3dSCy Schubertand
4412b15cb3dSCy Schubert<code>-x</code>
4422b15cb3dSCy Schubertoptions.
4432b15cb3dSCy SchubertSee the
4442b15cb3dSCy Schubert<code>tinker</code>
4452b15cb3dSCy Schubertconfiguration file directive for other options.
4462b15cb3dSCy Schubert<div class="node">
4472b15cb3dSCy Schubert<p><hr>
448*a25439b6SCy Schubert<a name="ntpd-force_002dstep_002donce"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-jaildir">ntpd jaildir</a>,
4492b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-panicgate">ntpd panicgate</a>,
4502b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
4512b15cb3dSCy Schubert<br>
4522b15cb3dSCy Schubert</div>
4532b15cb3dSCy Schubert
454*a25439b6SCy Schubert<h4 class="subsection">force-step-once option (-G)</h4>
455*a25439b6SCy Schubert
456*a25439b6SCy Schubert<p><a name="index-ntpd_002dforce_002dstep_002donce-11"></a>
457*a25439b6SCy SchubertThis is the &ldquo;step any initial offset correction.&rdquo; option.
458*a25439b6SCy SchubertNormally,
459*a25439b6SCy Schubert<code>ntpd</code>
460*a25439b6SCy Schubertsteps the time if the time offset exceeds the step threshold,
461*a25439b6SCy Schubertwhich is 128 ms by default, and otherwise slews the time.
462*a25439b6SCy SchubertThis option forces the initial offset correction to be stepped,
463*a25439b6SCy Schubertso the highest time accuracy can be achieved quickly.
464*a25439b6SCy SchubertHowever, this may also cause the time to be stepped back
465*a25439b6SCy Schubertso this option must not be used if
466*a25439b6SCy Schubertapplications requiring monotonic time are running.
467*a25439b6SCy SchubertSee the <code>tinker</code> configuration file directive for other options.
468*a25439b6SCy Schubert<div class="node">
469*a25439b6SCy Schubert<p><hr>
470*a25439b6SCy Schubert<a name="ntpd-jaildir"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-interface">ntpd interface</a>,
471*a25439b6SCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-force_002dstep_002donce">ntpd force-step-once</a>,
472*a25439b6SCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
473*a25439b6SCy Schubert<br>
474*a25439b6SCy Schubert</div>
475*a25439b6SCy Schubert
4762b15cb3dSCy Schubert<h4 class="subsection">jaildir option (-i)</h4>
4772b15cb3dSCy Schubert
478*a25439b6SCy Schubert<p><a name="index-ntpd_002djaildir-12"></a>
4792b15cb3dSCy SchubertThis is the &ldquo;jail directory&rdquo; option.
4802b15cb3dSCy SchubertThis option takes a string argument.
4812b15cb3dSCy Schubert
4822b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
4832b15cb3dSCy Schubert     <ul>
4842b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
4852b15cb3dSCy Schubert</ul>
4862b15cb3dSCy Schubert
4872b15cb3dSCy Schubert  <p>Chroot the server to the directory
4882b15cb3dSCy Schubert<kbd>jaildir</kbd>
4892b15cb3dSCy Schubert.
4902b15cb3dSCy SchubertThis option also implies that the server attempts to drop root privileges at startup.
4912b15cb3dSCy SchubertYou may need to also specify a
4922b15cb3dSCy Schubert<code>-u</code>
4932b15cb3dSCy Schubertoption.
4942b15cb3dSCy SchubertThis option is only available if the OS supports adjusting the clock
4952b15cb3dSCy Schubertwithout full root privileges.
4962b15cb3dSCy SchubertThis option is supported under NetBSD (configure with
4972b15cb3dSCy Schubert<code>--enable-clockctl</code>) or Linux (configure with
4982b15cb3dSCy Schubert<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
4992b15cb3dSCy Schubert<div class="node">
5002b15cb3dSCy Schubert<p><hr>
5012b15cb3dSCy Schubert<a name="ntpd-interface"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-keyfile">ntpd keyfile</a>,
5022b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-jaildir">ntpd jaildir</a>,
5032b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
5042b15cb3dSCy Schubert<br>
5052b15cb3dSCy Schubert</div>
5062b15cb3dSCy Schubert
5072b15cb3dSCy Schubert<h4 class="subsection">interface option (-I)</h4>
5082b15cb3dSCy Schubert
509*a25439b6SCy Schubert<p><a name="index-ntpd_002dinterface-13"></a>
5102b15cb3dSCy SchubertThis is the &ldquo;listen on an interface name or address&rdquo; option.
5112b15cb3dSCy SchubertThis option takes a string argument <span class="file">iface</span>.
5122b15cb3dSCy Schubert
5132b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
5142b15cb3dSCy Schubert     <ul>
5152b15cb3dSCy Schubert<li>may appear an unlimited number of times.
5162b15cb3dSCy Schubert</ul>
5172b15cb3dSCy Schubert
5182b15cb3dSCy Schubert  <p>Open the network address given, or all the addresses associated with the
5192b15cb3dSCy Schubertgiven interface name.  This option may appear multiple times.  This option
5202b15cb3dSCy Schubertalso implies not opening other addresses, except wildcard and localhost.
5212b15cb3dSCy SchubertThis option is deprecated. Please consider using the configuration file
5222b15cb3dSCy Schubert<code>interface</code> command, which is more versatile.
5232b15cb3dSCy Schubert<div class="node">
5242b15cb3dSCy Schubert<p><hr>
5252b15cb3dSCy Schubert<a name="ntpd-keyfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-logfile">ntpd logfile</a>,
5262b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-interface">ntpd interface</a>,
5272b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
5282b15cb3dSCy Schubert<br>
5292b15cb3dSCy Schubert</div>
5302b15cb3dSCy Schubert
5312b15cb3dSCy Schubert<h4 class="subsection">keyfile option (-k)</h4>
5322b15cb3dSCy Schubert
533*a25439b6SCy Schubert<p><a name="index-ntpd_002dkeyfile-14"></a>
5342b15cb3dSCy SchubertThis is the &ldquo;path to symmetric keys&rdquo; option.
5352b15cb3dSCy SchubertThis option takes a string argument.
5362b15cb3dSCy SchubertSpecify the name and path of the symmetric key file.
5372b15cb3dSCy Schubert<span class="file">/etc/ntp.keys</span>
5382b15cb3dSCy Schubertis the default.
5392b15cb3dSCy SchubertThis is the same operation as the
5402b15cb3dSCy Schubert<code>keys</code> <kbd>keyfile</kbd>
5412b15cb3dSCy Schubertconfiguration file directive.
5422b15cb3dSCy Schubert<div class="node">
5432b15cb3dSCy Schubert<p><hr>
5442b15cb3dSCy Schubert<a name="ntpd-logfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-novirtualips">ntpd novirtualips</a>,
5452b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-keyfile">ntpd keyfile</a>,
5462b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
5472b15cb3dSCy Schubert<br>
5482b15cb3dSCy Schubert</div>
5492b15cb3dSCy Schubert
5502b15cb3dSCy Schubert<h4 class="subsection">logfile option (-l)</h4>
5512b15cb3dSCy Schubert
552*a25439b6SCy Schubert<p><a name="index-ntpd_002dlogfile-15"></a>
5532b15cb3dSCy SchubertThis is the &ldquo;path to the log file&rdquo; option.
5542b15cb3dSCy SchubertThis option takes a string argument.
5552b15cb3dSCy SchubertSpecify the name and path of the log file.
5562b15cb3dSCy SchubertThe default is the system log file.
5572b15cb3dSCy SchubertThis is the same operation as the
5582b15cb3dSCy Schubert<code>logfile</code> <kbd>logfile</kbd>
5592b15cb3dSCy Schubertconfiguration file directive.
5602b15cb3dSCy Schubert<div class="node">
5612b15cb3dSCy Schubert<p><hr>
5622b15cb3dSCy Schubert<a name="ntpd-novirtualips"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>,
5632b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-logfile">ntpd logfile</a>,
5642b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
5652b15cb3dSCy Schubert<br>
5662b15cb3dSCy Schubert</div>
5672b15cb3dSCy Schubert
5682b15cb3dSCy Schubert<h4 class="subsection">novirtualips option (-L)</h4>
5692b15cb3dSCy Schubert
570*a25439b6SCy Schubert<p><a name="index-ntpd_002dnovirtualips-16"></a>
5712b15cb3dSCy SchubertThis is the &ldquo;do not listen to virtual interfaces&rdquo; option.
5722b15cb3dSCy SchubertDo not listen to virtual interfaces, defined as those with
5732b15cb3dSCy Schubertnames containing a colon.  This option is deprecated.  Please
5742b15cb3dSCy Schubertconsider using the configuration file <code>interface</code> command, which
5752b15cb3dSCy Schubertis more versatile.
5762b15cb3dSCy Schubert<div class="node">
5772b15cb3dSCy Schubert<p><hr>
5782b15cb3dSCy Schubert<a name="ntpd-modifymmtimer"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-nice">ntpd nice</a>,
5792b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-novirtualips">ntpd novirtualips</a>,
5802b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
5812b15cb3dSCy Schubert<br>
5822b15cb3dSCy Schubert</div>
5832b15cb3dSCy Schubert
5842b15cb3dSCy Schubert<h4 class="subsection">modifymmtimer option (-M)</h4>
5852b15cb3dSCy Schubert
586*a25439b6SCy Schubert<p><a name="index-ntpd_002dmodifymmtimer-17"></a>
5872b15cb3dSCy SchubertThis is the &ldquo;modify multimedia timer (windows only)&rdquo; option.
5882b15cb3dSCy Schubert
5892b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
5902b15cb3dSCy Schubert     <ul>
5912b15cb3dSCy Schubert<li>must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
5922b15cb3dSCy Schubert</ul>
5932b15cb3dSCy Schubert
5942b15cb3dSCy Schubert  <p>Set the Windows Multimedia Timer to highest resolution.  This
5952b15cb3dSCy Schubertensures the resolution does not change while ntpd is running,
5962b15cb3dSCy Schubertavoiding timekeeping glitches associated with changes.
5972b15cb3dSCy Schubert<div class="node">
5982b15cb3dSCy Schubert<p><hr>
5992b15cb3dSCy Schubert<a name="ntpd-nice"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-pidfile">ntpd pidfile</a>,
6002b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>,
6012b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
6022b15cb3dSCy Schubert<br>
6032b15cb3dSCy Schubert</div>
6042b15cb3dSCy Schubert
6052b15cb3dSCy Schubert<h4 class="subsection">nice option (-N)</h4>
6062b15cb3dSCy Schubert
607*a25439b6SCy Schubert<p><a name="index-ntpd_002dnice-18"></a>
6082b15cb3dSCy SchubertThis is the &ldquo;run at high priority&rdquo; option.
6092b15cb3dSCy SchubertTo the extent permitted by the operating system, run
6102b15cb3dSCy Schubert<code>ntpd</code>
6112b15cb3dSCy Schubertat the highest priority.
6122b15cb3dSCy Schubert<div class="node">
6132b15cb3dSCy Schubert<p><hr>
6142b15cb3dSCy Schubert<a name="ntpd-pidfile"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-priority">ntpd priority</a>,
6152b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-nice">ntpd nice</a>,
6162b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
6172b15cb3dSCy Schubert<br>
6182b15cb3dSCy Schubert</div>
6192b15cb3dSCy Schubert
6202b15cb3dSCy Schubert<h4 class="subsection">pidfile option (-p)</h4>
6212b15cb3dSCy Schubert
622*a25439b6SCy Schubert<p><a name="index-ntpd_002dpidfile-19"></a>
6232b15cb3dSCy SchubertThis is the &ldquo;path to the pid file&rdquo; option.
6242b15cb3dSCy SchubertThis option takes a string argument.
6252b15cb3dSCy SchubertSpecify the name and path of the file used to record
6262b15cb3dSCy Schubert<code>ntpd</code>'s
6272b15cb3dSCy Schubertprocess ID.
6282b15cb3dSCy SchubertThis is the same operation as the
6292b15cb3dSCy Schubert<code>pidfile</code> <kbd>pidfile</kbd>
6302b15cb3dSCy Schubertconfiguration file directive.
6312b15cb3dSCy Schubert<div class="node">
6322b15cb3dSCy Schubert<p><hr>
6332b15cb3dSCy Schubert<a name="ntpd-priority"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-quit">ntpd quit</a>,
6342b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-pidfile">ntpd pidfile</a>,
6352b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
6362b15cb3dSCy Schubert<br>
6372b15cb3dSCy Schubert</div>
6382b15cb3dSCy Schubert
6392b15cb3dSCy Schubert<h4 class="subsection">priority option (-P)</h4>
6402b15cb3dSCy Schubert
641*a25439b6SCy Schubert<p><a name="index-ntpd_002dpriority-20"></a>
6422b15cb3dSCy SchubertThis is the &ldquo;process priority&rdquo; option.
6432b15cb3dSCy SchubertThis option takes a number argument.
6442b15cb3dSCy SchubertTo the extent permitted by the operating system, run
6452b15cb3dSCy Schubert<code>ntpd</code>
6462b15cb3dSCy Schubertat the specified
6472b15cb3dSCy Schubert<code>sched_setscheduler(SCHED_FIFO)</code>
6482b15cb3dSCy Schubertpriority.
6492b15cb3dSCy Schubert<div class="node">
6502b15cb3dSCy Schubert<p><hr>
6512b15cb3dSCy Schubert<a name="ntpd-quit"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-propagationdelay">ntpd propagationdelay</a>,
6522b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-priority">ntpd priority</a>,
6532b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
6542b15cb3dSCy Schubert<br>
6552b15cb3dSCy Schubert</div>
6562b15cb3dSCy Schubert
6572b15cb3dSCy Schubert<h4 class="subsection">quit option (-q)</h4>
6582b15cb3dSCy Schubert
659*a25439b6SCy Schubert<p><a name="index-ntpd_002dquit-21"></a>
6602b15cb3dSCy SchubertThis is the &ldquo;set the time and quit&rdquo; option.
6612b15cb3dSCy Schubert
6622b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
6632b15cb3dSCy Schubert     <ul>
6642b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
6652b15cb3dSCy Schubertsaveconfigquit, wait-sync.
6662b15cb3dSCy Schubert</ul>
6672b15cb3dSCy Schubert
6682b15cb3dSCy Schubert  <p><code>ntpd</code>
6692b15cb3dSCy Schubertwill not daemonize and will exit after the clock is first
6702b15cb3dSCy Schubertsynchronized.  This behavior mimics that of the
6712b15cb3dSCy Schubert<code>ntpdate</code>
6722b15cb3dSCy Schubertprogram, which will soon be replaced with a shell script.
6732b15cb3dSCy SchubertThe
6742b15cb3dSCy Schubert<code>-g</code>
6752b15cb3dSCy Schubertand
6762b15cb3dSCy Schubert<code>-x</code>
6772b15cb3dSCy Schubertoptions can be used with this option.
6782b15cb3dSCy SchubertNote: The kernel time discipline is disabled with this option.
6792b15cb3dSCy Schubert<div class="node">
6802b15cb3dSCy Schubert<p><hr>
6812b15cb3dSCy Schubert<a name="ntpd-propagationdelay"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>,
6822b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-quit">ntpd quit</a>,
6832b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
6842b15cb3dSCy Schubert<br>
6852b15cb3dSCy Schubert</div>
6862b15cb3dSCy Schubert
6872b15cb3dSCy Schubert<h4 class="subsection">propagationdelay option (-r)</h4>
6882b15cb3dSCy Schubert
689*a25439b6SCy Schubert<p><a name="index-ntpd_002dpropagationdelay-22"></a>
6902b15cb3dSCy SchubertThis is the &ldquo;broadcast/propagation delay&rdquo; option.
6912b15cb3dSCy SchubertThis option takes a string argument.
6922b15cb3dSCy 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.
6932b15cb3dSCy Schubert<div class="node">
6942b15cb3dSCy Schubert<p><hr>
6952b15cb3dSCy Schubert<a name="ntpd-saveconfigquit"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-statsdir">ntpd statsdir</a>,
6962b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-propagationdelay">ntpd propagationdelay</a>,
6972b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
6982b15cb3dSCy Schubert<br>
6992b15cb3dSCy Schubert</div>
7002b15cb3dSCy Schubert
7012b15cb3dSCy Schubert<h4 class="subsection">saveconfigquit option</h4>
7022b15cb3dSCy Schubert
703*a25439b6SCy Schubert<p><a name="index-ntpd_002dsaveconfigquit-23"></a>
7042b15cb3dSCy SchubertThis is the &ldquo;save parsed configuration and quit&rdquo; option.
7052b15cb3dSCy SchubertThis option takes a string argument.
7062b15cb3dSCy Schubert
7072b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
7082b15cb3dSCy Schubert     <ul>
7092b15cb3dSCy Schubert<li>must be compiled in by defining <code>SAVECONFIG</code> during the compilation.
7102b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
7112b15cb3dSCy Schubertquit, wait-sync.
7122b15cb3dSCy Schubert</ul>
7132b15cb3dSCy Schubert
7142b15cb3dSCy Schubert  <p>Cause <code>ntpd</code> to parse its startup configuration file and save an
7152b15cb3dSCy Schubertequivalent to the given filename and exit.  This option was
7162b15cb3dSCy Schubertdesigned for automated testing.
7172b15cb3dSCy Schubert<div class="node">
7182b15cb3dSCy Schubert<p><hr>
7192b15cb3dSCy Schubert<a name="ntpd-statsdir"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-trustedkey">ntpd trustedkey</a>,
7202b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>,
7212b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
7222b15cb3dSCy Schubert<br>
7232b15cb3dSCy Schubert</div>
7242b15cb3dSCy Schubert
7252b15cb3dSCy Schubert<h4 class="subsection">statsdir option (-s)</h4>
7262b15cb3dSCy Schubert
727*a25439b6SCy Schubert<p><a name="index-ntpd_002dstatsdir-24"></a>
7282b15cb3dSCy SchubertThis is the &ldquo;statistics file location&rdquo; option.
7292b15cb3dSCy SchubertThis option takes a string argument.
7302b15cb3dSCy SchubertSpecify the directory path for files created by the statistics facility.
7312b15cb3dSCy SchubertThis is the same operation as the
7322b15cb3dSCy Schubert<code>statsdir</code> <kbd>statsdir</kbd>
7332b15cb3dSCy Schubertconfiguration file directive.
7342b15cb3dSCy Schubert<div class="node">
7352b15cb3dSCy Schubert<p><hr>
7362b15cb3dSCy Schubert<a name="ntpd-trustedkey"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-user">ntpd user</a>,
7372b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-statsdir">ntpd statsdir</a>,
7382b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
7392b15cb3dSCy Schubert<br>
7402b15cb3dSCy Schubert</div>
7412b15cb3dSCy Schubert
7422b15cb3dSCy Schubert<h4 class="subsection">trustedkey option (-t)</h4>
7432b15cb3dSCy Schubert
744*a25439b6SCy Schubert<p><a name="index-ntpd_002dtrustedkey-25"></a>
7452b15cb3dSCy SchubertThis is the &ldquo;trusted key number&rdquo; option.
7462b15cb3dSCy SchubertThis option takes a string argument <span class="file">tkey</span>.
7472b15cb3dSCy Schubert
7482b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
7492b15cb3dSCy Schubert     <ul>
7502b15cb3dSCy Schubert<li>may appear an unlimited number of times.
7512b15cb3dSCy Schubert</ul>
7522b15cb3dSCy Schubert
7532b15cb3dSCy Schubert  <p>Add the specified key number to the trusted key list.
7542b15cb3dSCy Schubert<div class="node">
7552b15cb3dSCy Schubert<p><hr>
7562b15cb3dSCy Schubert<a name="ntpd-user"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-updateinterval">ntpd updateinterval</a>,
7572b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-trustedkey">ntpd trustedkey</a>,
7582b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
7592b15cb3dSCy Schubert<br>
7602b15cb3dSCy Schubert</div>
7612b15cb3dSCy Schubert
7622b15cb3dSCy Schubert<h4 class="subsection">user option (-u)</h4>
7632b15cb3dSCy Schubert
764*a25439b6SCy Schubert<p><a name="index-ntpd_002duser-26"></a>
7652b15cb3dSCy SchubertThis is the &ldquo;run as userid (or userid:groupid)&rdquo; option.
7662b15cb3dSCy SchubertThis option takes a string argument.
7672b15cb3dSCy Schubert
7682b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
7692b15cb3dSCy Schubert     <ul>
7702b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
7712b15cb3dSCy Schubert</ul>
7722b15cb3dSCy Schubert
7732b15cb3dSCy Schubert  <p>Specify a user, and optionally a group, to switch to.
7742b15cb3dSCy SchubertThis option is only available if the OS supports adjusting the clock
7752b15cb3dSCy Schubertwithout full root privileges.
7762b15cb3dSCy SchubertThis option is supported under NetBSD (configure with
7772b15cb3dSCy Schubert<code>--enable-clockctl</code>) or Linux (configure with
7782b15cb3dSCy Schubert<code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
7792b15cb3dSCy Schubert<div class="node">
7802b15cb3dSCy Schubert<p><hr>
7812b15cb3dSCy Schubert<a name="ntpd-updateinterval"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-wait_002dsync">ntpd wait-sync</a>,
7822b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-user">ntpd user</a>,
7832b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
7842b15cb3dSCy Schubert<br>
7852b15cb3dSCy Schubert</div>
7862b15cb3dSCy Schubert
7872b15cb3dSCy Schubert<h4 class="subsection">updateinterval option (-U)</h4>
7882b15cb3dSCy Schubert
789*a25439b6SCy Schubert<p><a name="index-ntpd_002dupdateinterval-27"></a>
7902b15cb3dSCy SchubertThis is the &ldquo;interval in seconds between scans for new or dropped interfaces&rdquo; option.
7912b15cb3dSCy SchubertThis option takes a number argument.
7922b15cb3dSCy SchubertGive the time in seconds between two scans for new or dropped interfaces.
7932b15cb3dSCy SchubertFor systems with routing socket support the scans will be performed shortly after the interface change
7942b15cb3dSCy Schuberthas been detected by the system.
7952b15cb3dSCy SchubertUse 0 to disable scanning. 60 seconds is the minimum time between scans.
7962b15cb3dSCy Schubert<div class="node">
7972b15cb3dSCy Schubert<p><hr>
7982b15cb3dSCy Schubert<a name="ntpd-wait_002dsync"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-slew">ntpd slew</a>,
7992b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-updateinterval">ntpd updateinterval</a>,
8002b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
8012b15cb3dSCy Schubert<br>
8022b15cb3dSCy Schubert</div>
8032b15cb3dSCy Schubert
8042b15cb3dSCy Schubert<h4 class="subsection">wait-sync option (-w)</h4>
8052b15cb3dSCy Schubert
806*a25439b6SCy Schubert<p><a name="index-ntpd_002dwait_002dsync-28"></a>
8072b15cb3dSCy SchubertThis is the &ldquo;seconds to wait for first clock sync&rdquo; option.
8082b15cb3dSCy SchubertThis option takes a number argument.
8092b15cb3dSCy Schubert
8102b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
8112b15cb3dSCy Schubert     <ul>
8122b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_WORKING_FORK</code> during the compilation.
8132b15cb3dSCy Schubert<li>must not appear in combination with any of the following options:
8142b15cb3dSCy Schubertnofork, quit, saveconfigquit.
8152b15cb3dSCy Schubert</ul>
8162b15cb3dSCy Schubert
8172b15cb3dSCy Schubert  <p>If greater than zero, alters <code>ntpd</code>'s behavior when forking to
8182b15cb3dSCy Schubertdaemonize.  Instead of exiting with status 0 immediately after
8192b15cb3dSCy Schubertthe fork, the parent waits up to the specified number of
8202b15cb3dSCy Schubertseconds for the child to first synchronize the clock.  The exit
8212b15cb3dSCy Schubertstatus is zero (success) if the clock was synchronized,
8222b15cb3dSCy Schubertotherwise it is <code>ETIMEDOUT</code>.
8232b15cb3dSCy SchubertThis provides the option for a script starting <code>ntpd</code> to easily
8242b15cb3dSCy Schubertwait for the first set of the clock before proceeding.
8252b15cb3dSCy Schubert<div class="node">
8262b15cb3dSCy Schubert<p><hr>
8272b15cb3dSCy Schubert<a name="ntpd-slew"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-usepcc">ntpd usepcc</a>,
8282b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-wait_002dsync">ntpd wait-sync</a>,
8292b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
8302b15cb3dSCy Schubert<br>
8312b15cb3dSCy Schubert</div>
8322b15cb3dSCy Schubert
8332b15cb3dSCy Schubert<h4 class="subsection">slew option (-x)</h4>
8342b15cb3dSCy Schubert
835*a25439b6SCy Schubert<p><a name="index-ntpd_002dslew-29"></a>
8362b15cb3dSCy SchubertThis is the &ldquo;slew up to 600 seconds&rdquo; option.
8372b15cb3dSCy 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.
8382b15cb3dSCy SchubertThis option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually.
8392b15cb3dSCy 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.
8402b15cb3dSCy SchubertThus, an adjustment as much as 600 s will take almost 14 days to complete.
8412b15cb3dSCy SchubertThis option can be used with the
8422b15cb3dSCy Schubert<code>-g</code>
8432b15cb3dSCy Schubertand
8442b15cb3dSCy Schubert<code>-q</code>
8452b15cb3dSCy Schubertoptions.
8462b15cb3dSCy SchubertSee the
8472b15cb3dSCy Schubert<code>tinker</code>
8482b15cb3dSCy Schubertconfiguration file directive for other options.
8492b15cb3dSCy SchubertNote: The kernel time discipline is disabled with this option.
8502b15cb3dSCy Schubert<div class="node">
8512b15cb3dSCy Schubert<p><hr>
8522b15cb3dSCy Schubert<a name="ntpd-usepcc"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-pccfreq">ntpd pccfreq</a>,
8532b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-slew">ntpd slew</a>,
8542b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
8552b15cb3dSCy Schubert<br>
8562b15cb3dSCy Schubert</div>
8572b15cb3dSCy Schubert
8582b15cb3dSCy Schubert<h4 class="subsection">usepcc option</h4>
8592b15cb3dSCy Schubert
860*a25439b6SCy Schubert<p><a name="index-ntpd_002dusepcc-30"></a>
8612b15cb3dSCy SchubertThis is the &ldquo;use cpu cycle counter (windows only)&rdquo; option.
8622b15cb3dSCy Schubert
8632b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
8642b15cb3dSCy Schubert     <ul>
8652b15cb3dSCy Schubert<li>must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
8662b15cb3dSCy Schubert</ul>
8672b15cb3dSCy Schubert
8682b15cb3dSCy Schubert  <p>Attempt to substitute the CPU counter for <code>QueryPerformanceCounter</code>.
8692b15cb3dSCy SchubertThe CPU counter and <code>QueryPerformanceCounter</code> are compared, and if
8702b15cb3dSCy Schubertthey have the same frequency, the CPU counter (RDTSC on x86) is
8712b15cb3dSCy Schubertused directly, saving the overhead of a system call.
8722b15cb3dSCy Schubert<div class="node">
8732b15cb3dSCy Schubert<p><hr>
8742b15cb3dSCy Schubert<a name="ntpd-pccfreq"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-mdns">ntpd mdns</a>,
8752b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-usepcc">ntpd usepcc</a>,
8762b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
8772b15cb3dSCy Schubert<br>
8782b15cb3dSCy Schubert</div>
8792b15cb3dSCy Schubert
8802b15cb3dSCy Schubert<h4 class="subsection">pccfreq option</h4>
8812b15cb3dSCy Schubert
882*a25439b6SCy Schubert<p><a name="index-ntpd_002dpccfreq-31"></a>
8832b15cb3dSCy SchubertThis is the &ldquo;force cpu cycle counter use (windows only)&rdquo; option.
8842b15cb3dSCy SchubertThis option takes a string argument.
8852b15cb3dSCy Schubert
8862b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
8872b15cb3dSCy Schubert     <ul>
8882b15cb3dSCy Schubert<li>must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
8892b15cb3dSCy Schubert</ul>
8902b15cb3dSCy Schubert
8912b15cb3dSCy Schubert  <p>Force substitution the CPU counter for <code>QueryPerformanceCounter</code>.
8922b15cb3dSCy SchubertThe CPU counter (RDTSC on x86) is used unconditionally with the
8932b15cb3dSCy Schubertgiven frequency (in Hz).
8942b15cb3dSCy Schubert<div class="node">
8952b15cb3dSCy Schubert<p><hr>
8962b15cb3dSCy Schubert<a name="ntpd-mdns"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-config">ntpd config</a>,
8972b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-pccfreq">ntpd pccfreq</a>,
8982b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
8992b15cb3dSCy Schubert<br>
9002b15cb3dSCy Schubert</div>
9012b15cb3dSCy Schubert
9022b15cb3dSCy Schubert<h4 class="subsection">mdns option (-m)</h4>
9032b15cb3dSCy Schubert
904*a25439b6SCy Schubert<p><a name="index-ntpd_002dmdns-32"></a>
9052b15cb3dSCy SchubertThis is the &ldquo;register with mdns as a ntp server&rdquo; option.
9062b15cb3dSCy Schubert
9072b15cb3dSCy Schubert<p class="noindent">This option has some usage constraints.  It:
9082b15cb3dSCy Schubert     <ul>
9092b15cb3dSCy Schubert<li>must be compiled in by defining <code>HAVE_DNSREGISTRATION</code> during the compilation.
9102b15cb3dSCy Schubert</ul>
9112b15cb3dSCy Schubert
9122b15cb3dSCy Schubert  <p>Registers as an NTP server with the local mDNS server which allows
9132b15cb3dSCy Schubertthe server to be discovered via mDNS client lookup.
9142b15cb3dSCy Schubert
9152b15cb3dSCy Schubert<div class="node">
9162b15cb3dSCy Schubert<p><hr>
9172b15cb3dSCy Schubert<a name="ntpd-config"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-exit-status">ntpd exit status</a>,
9182b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-mdns">ntpd mdns</a>,
9192b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
9202b15cb3dSCy Schubert<br>
9212b15cb3dSCy Schubert</div>
9222b15cb3dSCy Schubert
9232b15cb3dSCy Schubert<h4 class="subsection">presetting/configuring ntpd</h4>
9242b15cb3dSCy Schubert
9252b15cb3dSCy Schubert<p>Any option that is not marked as <i>not presettable</i> may be preset by
9262b15cb3dSCy 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
9272b15cb3dSCy Schubertthe options listed above in upper case and segmented with underscores.
9282b15cb3dSCy SchubertThe <code>NTPD</code> variable will be tokenized and parsed like
9292b15cb3dSCy Schubertthe command line.  The remaining variables are tested for existence and their
9302b15cb3dSCy Schubertvalues are treated like option arguments.
9312b15cb3dSCy Schubert
9322b15cb3dSCy Schubert  <p>The command line options relating to configuration and/or usage help are:
9332b15cb3dSCy Schubert
9342b15cb3dSCy Schubert<h5 class="subsubheading">version (-)</h5>
9352b15cb3dSCy Schubert
9362b15cb3dSCy Schubert<p>Print the program version to standard out, optionally with licensing
9372b15cb3dSCy Schubertinformation, then exit 0.  The optional argument specifies how much licensing
9382b15cb3dSCy Schubertdetail to provide.  The default is to print just the version.  The licensing infomation may be selected with an option argument.
9392b15cb3dSCy SchubertOnly the first letter of the argument is examined:
9402b15cb3dSCy Schubert
9412b15cb3dSCy Schubert     <dl>
9422b15cb3dSCy Schubert<dt><span class="samp">version</span><dd>Only print the version.  This is the default.
9432b15cb3dSCy Schubert<br><dt><span class="samp">copyright</span><dd>Name the copyright usage licensing terms.
9442b15cb3dSCy Schubert<br><dt><span class="samp">verbose</span><dd>Print the full copyright usage licensing terms.
9452b15cb3dSCy Schubert</dl>
9462b15cb3dSCy Schubert
9472b15cb3dSCy Schubert<div class="node">
9482b15cb3dSCy Schubert<p><hr>
9492b15cb3dSCy Schubert<a name="ntpd-exit-status"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Usage">ntpd Usage</a>,
9502b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-config">ntpd config</a>,
9512b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
9522b15cb3dSCy Schubert<br>
9532b15cb3dSCy Schubert</div>
9542b15cb3dSCy Schubert
9552b15cb3dSCy Schubert<h4 class="subsection">ntpd exit status</h4>
9562b15cb3dSCy Schubert
9572b15cb3dSCy Schubert<p>One of the following exit values will be returned:
9582b15cb3dSCy Schubert     <dl>
9592b15cb3dSCy Schubert<dt><span class="samp">0 (EXIT_SUCCESS)</span><dd>Successful program execution.
9602b15cb3dSCy Schubert<br><dt><span class="samp">1 (EXIT_FAILURE)</span><dd>The operation failed or the command syntax was not valid.
9612b15cb3dSCy Schubert</dl>
9622b15cb3dSCy Schubert  <div class="node">
9632b15cb3dSCy Schubert<p><hr>
9642b15cb3dSCy Schubert<a name="ntpd-Usage"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Files">ntpd Files</a>,
9652b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-exit-status">ntpd exit status</a>,
9662b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
9672b15cb3dSCy Schubert<br>
9682b15cb3dSCy Schubert</div>
9692b15cb3dSCy Schubert
9702b15cb3dSCy Schubert<h4 class="subsection">ntpd Usage</h4>
9712b15cb3dSCy Schubert
9722b15cb3dSCy Schubert<div class="node">
9732b15cb3dSCy Schubert<p><hr>
9742b15cb3dSCy Schubert<a name="ntpd-Files"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-See-Also">ntpd See Also</a>,
9752b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-Usage">ntpd Usage</a>,
9762b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
9772b15cb3dSCy Schubert<br>
9782b15cb3dSCy Schubert</div>
9792b15cb3dSCy Schubert
9802b15cb3dSCy Schubert<h4 class="subsection">ntpd Files</h4>
9812b15cb3dSCy Schubert
9822b15cb3dSCy Schubert<div class="node">
9832b15cb3dSCy Schubert<p><hr>
9842b15cb3dSCy Schubert<a name="ntpd-See-Also"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Bugs">ntpd Bugs</a>,
9852b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-Files">ntpd Files</a>,
9862b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
9872b15cb3dSCy Schubert<br>
9882b15cb3dSCy Schubert</div>
9892b15cb3dSCy Schubert
9902b15cb3dSCy Schubert<h4 class="subsection">ntpd See Also</h4>
9912b15cb3dSCy Schubert
9922b15cb3dSCy Schubert<div class="node">
9932b15cb3dSCy Schubert<p><hr>
9942b15cb3dSCy Schubert<a name="ntpd-Bugs"></a>Next:&nbsp;<a rel="next" accesskey="n" href="#ntpd-Notes">ntpd Notes</a>,
9952b15cb3dSCy SchubertPrevious:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-See-Also">ntpd See Also</a>,
9962b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
9972b15cb3dSCy Schubert<br>
9982b15cb3dSCy Schubert</div>
9992b15cb3dSCy Schubert
10002b15cb3dSCy Schubert<h4 class="subsection">ntpd Bugs</h4>
10012b15cb3dSCy Schubert
10022b15cb3dSCy Schubert<div class="node">
10032b15cb3dSCy Schubert<p><hr>
10042b15cb3dSCy Schubert<a name="ntpd-Notes"></a>Previous:&nbsp;<a rel="previous" accesskey="p" href="#ntpd-Bugs">ntpd Bugs</a>,
10052b15cb3dSCy SchubertUp:&nbsp;<a rel="up" accesskey="u" href="#ntpd-Invocation">ntpd Invocation</a>
10062b15cb3dSCy Schubert<br>
10072b15cb3dSCy Schubert</div>
10082b15cb3dSCy Schubert
10092b15cb3dSCy Schubert<h4 class="subsection">ntpd Notes</h4>
10102b15cb3dSCy Schubert
10112b15cb3dSCy Schubert<div class="node">
10122b15cb3dSCy Schubert<p><hr>
10132b15cb3dSCy Schubert<a name="Usage"></a>
10142b15cb3dSCy Schubert<br>
10152b15cb3dSCy Schubert</div>
10162b15cb3dSCy Schubert
10172b15cb3dSCy Schubert<!-- node-name,  next,  previous,  up -->
10182b15cb3dSCy Schubert<h3 class="section">Usage</h3>
10192b15cb3dSCy Schubert
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