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47 <h1 class="settitle" align="center">ntpd: Network Time Protocol (NTP) Daemon User’s Manual</h1>
56 Next: <a href="#ntpd-Description" accesskey="n" rel="next">ntpd Description</a>, Previous: <a href="dir.html#Top" accesskey="p" rel="prev">(dir)</a>, Up: <a href="dir.html#Top" accesskey="u" rel="up">(dir)</a> </p>
58 <a name="ntpd_003a-Network-Time-Protocol-_0028NTP_0029-Daemon-User-Manual"></a>
59 <h1 class="top">ntpd: Network Time Protocol (NTP) Daemon User Manual</h1>
61 <p>The <code>ntpd</code> program is an operating system daemon that synchronizes the
62 system clock to remote NTP time servers or local reference clocks.
63 It is a complete implementation of NTP version 4 defined by RFC-5905, but
64 also retains compatible with version 3 defined by RFC-1305 and versions
65 1 and 2, defined by RFC-1059 and RFC-1119, respectively.
66 The program can operate in any of several modes, including client/server,
67 symmetric and broadcast modes, and with both symmetric-key and public-key
70 <p>This document applies to version 4.2.8p13 of <code>ntpd</code>.
72 <a name="SEC_Overview"></a>
73 <h2 class="shortcontents-heading">Short Table of Contents</h2>
75 <div class="shortcontents">
76 <ul class="no-bullet">
77 <li><a name="stoc-Description" href="#toc-Description">1 Description</a></li>
82 <table class="menu" border="0" cellspacing="0">
83 <tr><td align="left" valign="top">• <a href="#ntpd-Description" accesskey="1">ntpd Description</a>:</td><td> </td><td align="left" valign="top">Description
85 <tr><td align="left" valign="top">• <a href="#ntpd-Invocation" accesskey="2">ntpd Invocation</a>:</td><td> </td><td align="left" valign="top">Invoking ntpd
87 <tr><td align="left" valign="top">• <a href="#Usage" accesskey="3">Usage</a>:</td><td> </td><td align="left" valign="top">Usage
92 <a name="ntpd-Description"></a>
95 Next: <a href="#ntpd-Invocation" accesskey="n" rel="next">ntpd Invocation</a>, Up: <a href="#Top" accesskey="u" rel="up">Top</a> </p>
97 <a name="Description"></a>
98 <h2 class="chapter">1 Description</h2>
100 <p>The <code>ntpd</code> program ordinarily requires
101 a configuration file described at ‘ntp.conf’.
102 This configuration file contains configuration commands described on
103 the pages listed above.
104 However a client can discover remote servers and configure them
106 This makes it possible to deploy a fleet of workstations without
107 specifying configuration details specific to the local environment.
109 <p>The <code>ntpd</code> program normally operates continuously while adjusting the
110 system time and frequency, but in some cases this might not be
112 With the <code>-q</code> option <code>ntpd</code> operates as in continuous mode, but
113 exits just after setting the clock for the first time.
114 Most applications will probably want to specify the <code>iburst</code>
115 option with the <code>server</code> command.
116 With this option an initial volley of messages is exchanged to
117 groom the data and set the clock in about ten seconds’ time.
118 If nothing is heard after a few minutes’ time,
119 the daemon times out and exits without setting the clock.
121 <table class="menu" border="0" cellspacing="0">
122 <tr><td align="left" valign="top">• <a href="#ntpd-Invocation" accesskey="1">ntpd Invocation</a>:</td><td> </td><td align="left" valign="top">
124 <tr><td align="left" valign="top">• <a href="#Usage" accesskey="2">Usage</a>:</td><td> </td><td align="left" valign="top">
129 <a name="ntpd-Invocation"></a>
132 Next: <a href="#Usage" accesskey="n" rel="next">Usage</a>, Previous: <a href="#ntpd-Description" accesskey="p" rel="prev">ntpd Description</a>, Up: <a href="#ntpd-Description" accesskey="u" rel="up">ntpd Description</a> </p>
134 <a name="Invoking-ntpd"></a>
135 <h3 class="section">1.1 Invoking ntpd</h3>
136 <a name="index-ntpd"></a>
137 <a name="index-NTP-daemon-program"></a>
143 utility is an operating system daemon which sets
144 and maintains the system time of day in synchronism with Internet
145 standard time servers.
146 It is a complete implementation of the
147 Network Time Protocol (NTP) version 4, as defined by RFC-5905,
148 but also retains compatibility with
149 version 3, as defined by RFC-1305, and versions 1
150 and 2, as defined by RFC-1059 and RFC-1119, respectively.
154 utility does most computations in 64-bit floating point
155 arithmetic and does relatively clumsy 64-bit fixed point operations
156 only when necessary to preserve the ultimate precision, about 232
158 While the ultimate precision is not achievable with
159 ordinary workstations and networks of today, it may be required
160 with future gigahertz CPU clocks and gigabit LANs.
165 <code>ntp.conf(5)</code>
166 configuration file at startup time in order to determine the
167 synchronization sources and operating modes.
168 It is also possible to
169 specify a working, although limited, configuration entirely on the
170 command line, obviating the need for a configuration file.
172 be particularly useful when the local host is to be configured as a
173 broadcast/multicast client, with all peers being determined by
174 listening to broadcasts at run time.
176 <p>If NetInfo support is built into
180 will attempt to read its configuration from the
181 NetInfo if the default
182 <code>ntp.conf(5)</code>
183 file cannot be read and no file is
190 variables can be displayed and
191 configuration options altered while the
195 <code>ntpq(1ntpqmdoc)</code>
197 <code>ntpdc(1ntpdcmdoc)</code>
202 starts it looks at the value of
203 <code>umask(2)</code>,
207 <code>umask(2)</code>
210 <p>This section was generated by <strong>AutoGen</strong>,
211 using the <code>agtexi-cmd</code> template and the option descriptions for the <code>ntpd</code> program.
212 This software is released under the NTP license, <http://ntp.org/license>.
214 <table class="menu" border="0" cellspacing="0">
215 <tr><td align="left" valign="top">• <a href="#ntpd-usage" accesskey="1">ntpd usage</a>:</td><td> </td><td align="left" valign="top">ntpd help/usage (<samp>--help</samp>)
217 <tr><td align="left" valign="top">• <a href="#ntpd-ipv4" accesskey="2">ntpd ipv4</a>:</td><td> </td><td align="left" valign="top">ipv4 option (-4)
219 <tr><td align="left" valign="top">• <a href="#ntpd-ipv6" accesskey="3">ntpd ipv6</a>:</td><td> </td><td align="left" valign="top">ipv6 option (-6)
221 <tr><td align="left" valign="top">• <a href="#ntpd-authreq" accesskey="4">ntpd authreq</a>:</td><td> </td><td align="left" valign="top">authreq option (-a)
223 <tr><td align="left" valign="top">• <a href="#ntpd-authnoreq" accesskey="5">ntpd authnoreq</a>:</td><td> </td><td align="left" valign="top">authnoreq option (-A)
225 <tr><td align="left" valign="top">• <a href="#ntpd-configfile" accesskey="6">ntpd configfile</a>:</td><td> </td><td align="left" valign="top">configfile option (-c)
227 <tr><td align="left" valign="top">• <a href="#ntpd-driftfile" accesskey="7">ntpd driftfile</a>:</td><td> </td><td align="left" valign="top">driftfile option (-f)
229 <tr><td align="left" valign="top">• <a href="#ntpd-panicgate" accesskey="8">ntpd panicgate</a>:</td><td> </td><td align="left" valign="top">panicgate option (-g)
231 <tr><td align="left" valign="top">• <a href="#ntpd-force_002dstep_002donce" accesskey="9">ntpd force-step-once</a>:</td><td> </td><td align="left" valign="top">force-step-once option (-G)
233 <tr><td align="left" valign="top">• <a href="#ntpd-jaildir">ntpd jaildir</a>:</td><td> </td><td align="left" valign="top">jaildir option (-i)
235 <tr><td align="left" valign="top">• <a href="#ntpd-interface">ntpd interface</a>:</td><td> </td><td align="left" valign="top">interface option (-I)
237 <tr><td align="left" valign="top">• <a href="#ntpd-keyfile">ntpd keyfile</a>:</td><td> </td><td align="left" valign="top">keyfile option (-k)
239 <tr><td align="left" valign="top">• <a href="#ntpd-logfile">ntpd logfile</a>:</td><td> </td><td align="left" valign="top">logfile option (-l)
241 <tr><td align="left" valign="top">• <a href="#ntpd-novirtualips">ntpd novirtualips</a>:</td><td> </td><td align="left" valign="top">novirtualips option (-L)
243 <tr><td align="left" valign="top">• <a href="#ntpd-modifymmtimer">ntpd modifymmtimer</a>:</td><td> </td><td align="left" valign="top">modifymmtimer option (-M)
245 <tr><td align="left" valign="top">• <a href="#ntpd-nice">ntpd nice</a>:</td><td> </td><td align="left" valign="top">nice option (-N)
247 <tr><td align="left" valign="top">• <a href="#ntpd-pidfile">ntpd pidfile</a>:</td><td> </td><td align="left" valign="top">pidfile option (-p)
249 <tr><td align="left" valign="top">• <a href="#ntpd-priority">ntpd priority</a>:</td><td> </td><td align="left" valign="top">priority option (-P)
251 <tr><td align="left" valign="top">• <a href="#ntpd-quit">ntpd quit</a>:</td><td> </td><td align="left" valign="top">quit option (-q)
253 <tr><td align="left" valign="top">• <a href="#ntpd-propagationdelay">ntpd propagationdelay</a>:</td><td> </td><td align="left" valign="top">propagationdelay option (-r)
255 <tr><td align="left" valign="top">• <a href="#ntpd-saveconfigquit">ntpd saveconfigquit</a>:</td><td> </td><td align="left" valign="top">saveconfigquit option
257 <tr><td align="left" valign="top">• <a href="#ntpd-statsdir">ntpd statsdir</a>:</td><td> </td><td align="left" valign="top">statsdir option (-s)
259 <tr><td align="left" valign="top">• <a href="#ntpd-trustedkey">ntpd trustedkey</a>:</td><td> </td><td align="left" valign="top">trustedkey option (-t)
261 <tr><td align="left" valign="top">• <a href="#ntpd-user">ntpd user</a>:</td><td> </td><td align="left" valign="top">user option (-u)
263 <tr><td align="left" valign="top">• <a href="#ntpd-updateinterval">ntpd updateinterval</a>:</td><td> </td><td align="left" valign="top">updateinterval option (-U)
265 <tr><td align="left" valign="top">• <a href="#ntpd-wait_002dsync">ntpd wait-sync</a>:</td><td> </td><td align="left" valign="top">wait-sync option (-w)
267 <tr><td align="left" valign="top">• <a href="#ntpd-slew">ntpd slew</a>:</td><td> </td><td align="left" valign="top">slew option (-x)
269 <tr><td align="left" valign="top">• <a href="#ntpd-usepcc">ntpd usepcc</a>:</td><td> </td><td align="left" valign="top">usepcc option
271 <tr><td align="left" valign="top">• <a href="#ntpd-pccfreq">ntpd pccfreq</a>:</td><td> </td><td align="left" valign="top">pccfreq option
273 <tr><td align="left" valign="top">• <a href="#ntpd-mdns">ntpd mdns</a>:</td><td> </td><td align="left" valign="top">mdns option (-m)
275 <tr><td align="left" valign="top">• <a href="#ntpd-config">ntpd config</a>:</td><td> </td><td align="left" valign="top">presetting/configuring ntpd
277 <tr><td align="left" valign="top">• <a href="#ntpd-exit-status">ntpd exit status</a>:</td><td> </td><td align="left" valign="top">exit status
279 <tr><td align="left" valign="top">• <a href="#ntpd-Usage">ntpd Usage</a>:</td><td> </td><td align="left" valign="top">Usage
281 <tr><td align="left" valign="top">• <a href="#ntpd-Files">ntpd Files</a>:</td><td> </td><td align="left" valign="top">Files
283 <tr><td align="left" valign="top">• <a href="#ntpd-See-Also">ntpd See Also</a>:</td><td> </td><td align="left" valign="top">See Also
285 <tr><td align="left" valign="top">• <a href="#ntpd-Bugs">ntpd Bugs</a>:</td><td> </td><td align="left" valign="top">Bugs
287 <tr><td align="left" valign="top">• <a href="#ntpd-Notes">ntpd Notes</a>:</td><td> </td><td align="left" valign="top">Notes
292 <a name="ntpd-usage"></a>
295 Next: <a href="#ntpd-ipv4" accesskey="n" rel="next">ntpd ipv4</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
297 <a name="ntpd-help_002fusage-_0028_002d_002dhelp_0029"></a>
298 <h4 class="subsection">1.1.1 ntpd help/usage (<samp>--help</samp>)</h4>
299 <a name="index-ntpd-help"></a>
301 <p>This is the automatically generated usage text for ntpd.
303 <p>The text printed is the same whether selected with the <code>help</code> option
304 (<samp>--help</samp>) or the <code>more-help</code> option (<samp>--more-help</samp>). <code>more-help</code> will print
305 the usage text by passing it through a pager program.
306 <code>more-help</code> is disabled on platforms without a working
307 <code>fork(2)</code> function. The <code>PAGER</code> environment variable is
308 used to select the program, defaulting to <samp>more</samp>. Both will exit
309 with a status code of 0.
311 <div class="example">
312 <pre class="example">ntpd - NTP daemon program - Ver. 4.2.8p12
313 Usage: ntpd [ -<flag> [<val>] | --<name>[{=| }<val>] ]... \
314 [ <server1> ... <serverN> ]
315 Flg Arg Option-Name Description
316 -4 no ipv4 Force IPv4 DNS name resolution
317 - prohibits the option 'ipv6'
318 -6 no ipv6 Force IPv6 DNS name resolution
319 - prohibits the option 'ipv4'
320 -a no authreq Require crypto authentication
321 - prohibits the option 'authnoreq'
322 -A no authnoreq Do not require crypto authentication
323 - prohibits the option 'authreq'
324 -b no bcastsync Allow us to sync to broadcast servers
325 -c Str configfile configuration file name
326 -d no debug-level Increase debug verbosity level
327 - may appear multiple times
328 -D Num set-debug-level Set the debug verbosity level
329 - may appear multiple times
330 -f Str driftfile frequency drift file name
331 -g no panicgate Allow the first adjustment to be Big
332 - may appear multiple times
333 -G no force-step-once Step any initial offset correction.
334 -i Str jaildir Jail directory
335 -I Str interface Listen on an interface name or address
336 - may appear multiple times
337 -k Str keyfile path to symmetric keys
338 -l Str logfile path to the log file
339 -L no novirtualips Do not listen to virtual interfaces
340 -n no nofork Do not fork
341 - prohibits the option 'wait-sync'
342 -N no nice Run at high priority
343 -p Str pidfile path to the PID file
344 -P Num priority Process priority
345 -q no quit Set the time and quit
346 - prohibits these options:
349 -r Str propagationdelay Broadcast/propagation delay
350 Str saveconfigquit Save parsed configuration and quit
351 - prohibits these options:
354 -s Str statsdir Statistics file location
355 -t Str trustedkey Trusted key number
356 - may appear multiple times
357 -u Str user Run as userid (or userid:groupid)
358 -U Num updateinterval interval in seconds between scans for new or dropped interfaces
359 Str var make ARG an ntp variable (RW)
360 - may appear multiple times
361 Str dvar make ARG an ntp variable (RW|DEF)
362 - may appear multiple times
363 -w Num wait-sync Seconds to wait for first clock sync
364 - prohibits these options:
368 -x no slew Slew up to 600 seconds
369 opt version output version information and exit
370 -? no help display extended usage information and exit
371 -! no more-help extended usage information passed thru pager
373 Options are specified by doubled hyphens and their name or by a single
374 hyphen and the flag character.
377 The following option preset mechanisms are supported:
378 - examining environment variables named NTPD_*
380 Please send bug reports to: <http://bugs.ntp.org, bugs@ntp.org>
384 <a name="ntpd-ipv4"></a>
387 Next: <a href="#ntpd-ipv6" accesskey="n" rel="next">ntpd ipv6</a>, Previous: <a href="#ntpd-usage" accesskey="p" rel="prev">ntpd usage</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
389 <a name="ipv4-option-_0028_002d4_0029"></a>
390 <h4 class="subsection">1.1.2 ipv4 option (-4)</h4>
391 <a name="index-ntpd_002dipv4"></a>
393 <p>This is the “force ipv4 dns name resolution” option.
395 <p>This option has some usage constraints. It:
397 <li> must not appear in combination with any of the following options:
401 <p>Force DNS resolution of following host names on the command line
402 to the IPv4 namespace.
404 <a name="ntpd-ipv6"></a>
407 Next: <a href="#ntpd-authreq" accesskey="n" rel="next">ntpd authreq</a>, Previous: <a href="#ntpd-ipv4" accesskey="p" rel="prev">ntpd ipv4</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
409 <a name="ipv6-option-_0028_002d6_0029"></a>
410 <h4 class="subsection">1.1.3 ipv6 option (-6)</h4>
411 <a name="index-ntpd_002dipv6"></a>
413 <p>This is the “force ipv6 dns name resolution” option.
415 <p>This option has some usage constraints. It:
417 <li> must not appear in combination with any of the following options:
421 <p>Force DNS resolution of following host names on the command line
422 to the IPv6 namespace.
424 <a name="ntpd-authreq"></a>
427 Next: <a href="#ntpd-authnoreq" accesskey="n" rel="next">ntpd authnoreq</a>, Previous: <a href="#ntpd-ipv6" accesskey="p" rel="prev">ntpd ipv6</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
429 <a name="authreq-option-_0028_002da_0029"></a>
430 <h4 class="subsection">1.1.4 authreq option (-a)</h4>
431 <a name="index-ntpd_002dauthreq"></a>
433 <p>This is the “require crypto authentication” option.
435 <p>This option has some usage constraints. It:
437 <li> must not appear in combination with any of the following options:
441 <p>Require cryptographic authentication for broadcast client,
442 multicast client and symmetric passive associations.
445 <a name="ntpd-authnoreq"></a>
448 Next: <a href="#ntpd-configfile" accesskey="n" rel="next">ntpd configfile</a>, Previous: <a href="#ntpd-authreq" accesskey="p" rel="prev">ntpd authreq</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
450 <a name="authnoreq-option-_0028_002dA_0029"></a>
451 <h4 class="subsection">1.1.5 authnoreq option (-A)</h4>
452 <a name="index-ntpd_002dauthnoreq"></a>
454 <p>This is the “do not require crypto authentication” option.
456 <p>This option has some usage constraints. It:
458 <li> must not appear in combination with any of the following options:
462 <p>Do not require cryptographic authentication for broadcast client,
463 multicast client and symmetric passive associations.
464 This is almost never a good idea.
466 <a name="ntpd-configfile"></a>
469 Next: <a href="#ntpd-driftfile" accesskey="n" rel="next">ntpd driftfile</a>, Previous: <a href="#ntpd-authnoreq" accesskey="p" rel="prev">ntpd authnoreq</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
471 <a name="configfile-option-_0028_002dc_0029"></a>
472 <h4 class="subsection">1.1.6 configfile option (-c)</h4>
473 <a name="index-ntpd_002dconfigfile"></a>
475 <p>This is the “configuration file name” option.
476 This option takes a string argument.
477 The name and path of the configuration file,
478 <samp>/etc/ntp.conf</samp>
481 <a name="ntpd-driftfile"></a>
484 Next: <a href="#ntpd-panicgate" accesskey="n" rel="next">ntpd panicgate</a>, Previous: <a href="#ntpd-configfile" accesskey="p" rel="prev">ntpd configfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
486 <a name="driftfile-option-_0028_002df_0029"></a>
487 <h4 class="subsection">1.1.7 driftfile option (-f)</h4>
488 <a name="index-ntpd_002ddriftfile"></a>
490 <p>This is the “frequency drift file name” option.
491 This option takes a string argument.
492 The name and path of the frequency file,
493 <samp>/etc/ntp.drift</samp>
495 This is the same operation as the
496 <code>driftfile</code> <kbd>driftfile</kbd>
497 configuration specification in the
498 <samp>/etc/ntp.conf</samp>
501 <a name="ntpd-panicgate"></a>
504 Next: <a href="#ntpd-force_002dstep_002donce" accesskey="n" rel="next">ntpd force-step-once</a>, Previous: <a href="#ntpd-driftfile" accesskey="p" rel="prev">ntpd driftfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
506 <a name="panicgate-option-_0028_002dg_0029"></a>
507 <h4 class="subsection">1.1.8 panicgate option (-g)</h4>
508 <a name="index-ntpd_002dpanicgate"></a>
510 <p>This is the “allow the first adjustment to be big” option.
512 <p>This option has some usage constraints. It:
514 <li> may appear an unlimited number of times.
519 exits 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,
521 will exit with a message to the system log. This option can be used with the
528 configuration file directive for other options.
530 <a name="ntpd-force_002dstep_002donce"></a>
533 Next: <a href="#ntpd-jaildir" accesskey="n" rel="next">ntpd jaildir</a>, Previous: <a href="#ntpd-panicgate" accesskey="p" rel="prev">ntpd panicgate</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
535 <a name="force_002dstep_002donce-option-_0028_002dG_0029"></a>
536 <h4 class="subsection">1.1.9 force-step-once option (-G)</h4>
537 <a name="index-ntpd_002dforce_002dstep_002donce"></a>
539 <p>This is the “step any initial offset correction.” option.
542 steps the time if the time offset exceeds the step threshold,
543 which is 128 ms by default, and otherwise slews the time.
544 This option forces the initial offset correction to be stepped,
545 so the highest time accuracy can be achieved quickly.
546 However, this may also cause the time to be stepped back
547 so this option must not be used if
548 applications requiring monotonic time are running.
549 See the <code>tinker</code> configuration file directive for other options.
551 <a name="ntpd-jaildir"></a>
554 Next: <a href="#ntpd-interface" accesskey="n" rel="next">ntpd interface</a>, Previous: <a href="#ntpd-force_002dstep_002donce" accesskey="p" rel="prev">ntpd force-step-once</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
556 <a name="jaildir-option-_0028_002di_0029"></a>
557 <h4 class="subsection">1.1.10 jaildir option (-i)</h4>
558 <a name="index-ntpd_002djaildir"></a>
560 <p>This is the “jail directory” option.
561 This option takes a string argument.
563 <p>This option has some usage constraints. It:
565 <li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
568 <p>Chroot the server to the directory
571 This option also implies that the server attempts to drop root privileges at startup.
572 You may need to also specify a
575 This option is only available if the OS supports adjusting the clock
576 without full root privileges.
577 This option is supported under NetBSD (configure with
578 <code>--enable-clockctl</code>) or Linux (configure with
579 <code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
581 <a name="ntpd-interface"></a>
584 Next: <a href="#ntpd-keyfile" accesskey="n" rel="next">ntpd keyfile</a>, Previous: <a href="#ntpd-jaildir" accesskey="p" rel="prev">ntpd jaildir</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
586 <a name="interface-option-_0028_002dI_0029"></a>
587 <h4 class="subsection">1.1.11 interface option (-I)</h4>
588 <a name="index-ntpd_002dinterface"></a>
590 <p>This is the “listen on an interface name or address” option.
591 This option takes a string argument <samp>iface</samp>.
593 <p>This option has some usage constraints. It:
595 <li> may appear an unlimited number of times.
598 <p>Open the network address given, or all the addresses associated with the
599 given interface name. This option may appear multiple times. This option
600 also implies not opening other addresses, except wildcard and localhost.
601 This option is deprecated. Please consider using the configuration file
602 <code>interface</code> command, which is more versatile.
604 <a name="ntpd-keyfile"></a>
607 Next: <a href="#ntpd-logfile" accesskey="n" rel="next">ntpd logfile</a>, Previous: <a href="#ntpd-interface" accesskey="p" rel="prev">ntpd interface</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
609 <a name="keyfile-option-_0028_002dk_0029"></a>
610 <h4 class="subsection">1.1.12 keyfile option (-k)</h4>
611 <a name="index-ntpd_002dkeyfile"></a>
613 <p>This is the “path to symmetric keys” option.
614 This option takes a string argument.
615 Specify the name and path of the symmetric key file.
616 <samp>/etc/ntp.keys</samp>
618 This is the same operation as the
619 <code>keys</code> <kbd>keyfile</kbd>
620 configuration file directive.
622 <a name="ntpd-logfile"></a>
625 Next: <a href="#ntpd-novirtualips" accesskey="n" rel="next">ntpd novirtualips</a>, Previous: <a href="#ntpd-keyfile" accesskey="p" rel="prev">ntpd keyfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
627 <a name="logfile-option-_0028_002dl_0029"></a>
628 <h4 class="subsection">1.1.13 logfile option (-l)</h4>
629 <a name="index-ntpd_002dlogfile"></a>
631 <p>This is the “path to the log file” option.
632 This option takes a string argument.
633 Specify the name and path of the log file.
634 The default is the system log file.
635 This is the same operation as the
636 <code>logfile</code> <kbd>logfile</kbd>
637 configuration file directive.
639 <a name="ntpd-novirtualips"></a>
642 Next: <a href="#ntpd-modifymmtimer" accesskey="n" rel="next">ntpd modifymmtimer</a>, Previous: <a href="#ntpd-logfile" accesskey="p" rel="prev">ntpd logfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
644 <a name="novirtualips-option-_0028_002dL_0029"></a>
645 <h4 class="subsection">1.1.14 novirtualips option (-L)</h4>
646 <a name="index-ntpd_002dnovirtualips"></a>
648 <p>This is the “do not listen to virtual interfaces” option.
649 Do not listen to virtual interfaces, defined as those with
650 names containing a colon. This option is deprecated. Please
651 consider using the configuration file <code>interface</code> command, which
654 <a name="ntpd-modifymmtimer"></a>
657 Next: <a href="#ntpd-nice" accesskey="n" rel="next">ntpd nice</a>, Previous: <a href="#ntpd-novirtualips" accesskey="p" rel="prev">ntpd novirtualips</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
659 <a name="modifymmtimer-option-_0028_002dM_0029"></a>
660 <h4 class="subsection">1.1.15 modifymmtimer option (-M)</h4>
661 <a name="index-ntpd_002dmodifymmtimer"></a>
663 <p>This is the “modify multimedia timer (windows only)” option.
665 <p>This option has some usage constraints. It:
667 <li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
670 <p>Set the Windows Multimedia Timer to highest resolution. This
671 ensures the resolution does not change while ntpd is running,
672 avoiding timekeeping glitches associated with changes.
674 <a name="ntpd-nice"></a>
677 Next: <a href="#ntpd-pidfile" accesskey="n" rel="next">ntpd pidfile</a>, Previous: <a href="#ntpd-modifymmtimer" accesskey="p" rel="prev">ntpd modifymmtimer</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
679 <a name="nice-option-_0028_002dN_0029"></a>
680 <h4 class="subsection">1.1.16 nice option (-N)</h4>
681 <a name="index-ntpd_002dnice"></a>
683 <p>This is the “run at high priority” option.
684 To the extent permitted by the operating system, run
686 at the highest priority.
688 <a name="ntpd-pidfile"></a>
691 Next: <a href="#ntpd-priority" accesskey="n" rel="next">ntpd priority</a>, Previous: <a href="#ntpd-nice" accesskey="p" rel="prev">ntpd nice</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
693 <a name="pidfile-option-_0028_002dp_0029"></a>
694 <h4 class="subsection">1.1.17 pidfile option (-p)</h4>
695 <a name="index-ntpd_002dpidfile"></a>
697 <p>This is the “path to the pid file” option.
698 This option takes a string argument.
699 Specify the name and path of the file used to record
700 <code>ntpd</code>’s
702 This is the same operation as the
703 <code>pidfile</code> <kbd>pidfile</kbd>
704 configuration file directive.
706 <a name="ntpd-priority"></a>
709 Next: <a href="#ntpd-quit" accesskey="n" rel="next">ntpd quit</a>, Previous: <a href="#ntpd-pidfile" accesskey="p" rel="prev">ntpd pidfile</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
711 <a name="priority-option-_0028_002dP_0029"></a>
712 <h4 class="subsection">1.1.18 priority option (-P)</h4>
713 <a name="index-ntpd_002dpriority"></a>
715 <p>This is the “process priority” option.
716 This option takes a number argument.
717 To the extent permitted by the operating system, run
720 <code>sched_setscheduler(SCHED_FIFO)</code>
723 <a name="ntpd-quit"></a>
726 Next: <a href="#ntpd-propagationdelay" accesskey="n" rel="next">ntpd propagationdelay</a>, Previous: <a href="#ntpd-priority" accesskey="p" rel="prev">ntpd priority</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
728 <a name="quit-option-_0028_002dq_0029"></a>
729 <h4 class="subsection">1.1.19 quit option (-q)</h4>
730 <a name="index-ntpd_002dquit"></a>
732 <p>This is the “set the time and quit” option.
734 <p>This option has some usage constraints. It:
736 <li> must not appear in combination with any of the following options:
737 saveconfigquit, wait-sync.
741 will not daemonize and will exit after the clock is first
742 synchronized. This behavior mimics that of the
744 program, which will soon be replaced with a shell script.
749 options can be used with this option.
750 Note: The kernel time discipline is disabled with this option.
752 <a name="ntpd-propagationdelay"></a>
755 Next: <a href="#ntpd-saveconfigquit" accesskey="n" rel="next">ntpd saveconfigquit</a>, Previous: <a href="#ntpd-quit" accesskey="p" rel="prev">ntpd quit</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
757 <a name="propagationdelay-option-_0028_002dr_0029"></a>
758 <h4 class="subsection">1.1.20 propagationdelay option (-r)</h4>
759 <a name="index-ntpd_002dpropagationdelay"></a>
761 <p>This is the “broadcast/propagation delay” option.
762 This option takes a string argument.
763 Specify 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.
765 <a name="ntpd-saveconfigquit"></a>
768 Next: <a href="#ntpd-statsdir" accesskey="n" rel="next">ntpd statsdir</a>, Previous: <a href="#ntpd-propagationdelay" accesskey="p" rel="prev">ntpd propagationdelay</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
770 <a name="saveconfigquit-option"></a>
771 <h4 class="subsection">1.1.21 saveconfigquit option</h4>
772 <a name="index-ntpd_002dsaveconfigquit"></a>
774 <p>This is the “save parsed configuration and quit” option.
775 This option takes a string argument.
777 <p>This option has some usage constraints. It:
779 <li> must be compiled in by defining <code>SAVECONFIG</code> during the compilation.
780 </li><li> must not appear in combination with any of the following options:
784 <p>Cause <code>ntpd</code> to parse its startup configuration file and save an
785 equivalent to the given filename and exit. This option was
786 designed for automated testing.
788 <a name="ntpd-statsdir"></a>
791 Next: <a href="#ntpd-trustedkey" accesskey="n" rel="next">ntpd trustedkey</a>, Previous: <a href="#ntpd-saveconfigquit" accesskey="p" rel="prev">ntpd saveconfigquit</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
793 <a name="statsdir-option-_0028_002ds_0029"></a>
794 <h4 class="subsection">1.1.22 statsdir option (-s)</h4>
795 <a name="index-ntpd_002dstatsdir"></a>
797 <p>This is the “statistics file location” option.
798 This option takes a string argument.
799 Specify the directory path for files created by the statistics facility.
800 This is the same operation as the
801 <code>statsdir</code> <kbd>statsdir</kbd>
802 configuration file directive.
804 <a name="ntpd-trustedkey"></a>
807 Next: <a href="#ntpd-user" accesskey="n" rel="next">ntpd user</a>, Previous: <a href="#ntpd-statsdir" accesskey="p" rel="prev">ntpd statsdir</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
809 <a name="trustedkey-option-_0028_002dt_0029"></a>
810 <h4 class="subsection">1.1.23 trustedkey option (-t)</h4>
811 <a name="index-ntpd_002dtrustedkey"></a>
813 <p>This is the “trusted key number” option.
814 This option takes a string argument <samp>tkey</samp>.
816 <p>This option has some usage constraints. It:
818 <li> may appear an unlimited number of times.
821 <p>Add the specified key number to the trusted key list.
823 <a name="ntpd-user"></a>
826 Next: <a href="#ntpd-updateinterval" accesskey="n" rel="next">ntpd updateinterval</a>, Previous: <a href="#ntpd-trustedkey" accesskey="p" rel="prev">ntpd trustedkey</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
828 <a name="user-option-_0028_002du_0029"></a>
829 <h4 class="subsection">1.1.24 user option (-u)</h4>
830 <a name="index-ntpd_002duser"></a>
832 <p>This is the “run as userid (or userid:groupid)” option.
833 This option takes a string argument.
835 <p>This option has some usage constraints. It:
837 <li> must be compiled in by defining <code>HAVE_DROPROOT</code> during the compilation.
840 <p>Specify a user, and optionally a group, to switch to.
841 This option is only available if the OS supports adjusting the clock
842 without full root privileges.
843 This option is supported under NetBSD (configure with
844 <code>--enable-clockctl</code>) or Linux (configure with
845 <code>--enable-linuxcaps</code>) or Solaris (configure with <code>--enable-solarisprivs</code>).
847 <a name="ntpd-updateinterval"></a>
850 Next: <a href="#ntpd-wait_002dsync" accesskey="n" rel="next">ntpd wait-sync</a>, Previous: <a href="#ntpd-user" accesskey="p" rel="prev">ntpd user</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
852 <a name="updateinterval-option-_0028_002dU_0029"></a>
853 <h4 class="subsection">1.1.25 updateinterval option (-U)</h4>
854 <a name="index-ntpd_002dupdateinterval"></a>
856 <p>This is the “interval in seconds between scans for new or dropped interfaces” option.
857 This option takes a number argument.
858 Give the time in seconds between two scans for new or dropped interfaces.
859 For systems with routing socket support the scans will be performed shortly after the interface change
860 has been detected by the system.
861 Use 0 to disable scanning. 60 seconds is the minimum time between scans.
863 <a name="ntpd-wait_002dsync"></a>
866 Next: <a href="#ntpd-slew" accesskey="n" rel="next">ntpd slew</a>, Previous: <a href="#ntpd-updateinterval" accesskey="p" rel="prev">ntpd updateinterval</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
868 <a name="wait_002dsync-option-_0028_002dw_0029"></a>
869 <h4 class="subsection">1.1.26 wait-sync option (-w)</h4>
870 <a name="index-ntpd_002dwait_002dsync"></a>
872 <p>This is the “seconds to wait for first clock sync” option.
873 This option takes a number argument.
875 <p>This option has some usage constraints. It:
877 <li> must be compiled in by defining <code>HAVE_WORKING_FORK</code> during the compilation.
878 </li><li> must not appear in combination with any of the following options:
879 nofork, quit, saveconfigquit.
882 <p>If greater than zero, alters <code>ntpd</code>’s behavior when forking to
883 daemonize. Instead of exiting with status 0 immediately after
884 the fork, the parent waits up to the specified number of
885 seconds for the child to first synchronize the clock. The exit
886 status is zero (success) if the clock was synchronized,
887 otherwise it is <code>ETIMEDOUT</code>.
888 This provides the option for a script starting <code>ntpd</code> to easily
889 wait for the first set of the clock before proceeding.
891 <a name="ntpd-slew"></a>
894 Next: <a href="#ntpd-usepcc" accesskey="n" rel="next">ntpd usepcc</a>, Previous: <a href="#ntpd-wait_002dsync" accesskey="p" rel="prev">ntpd wait-sync</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
896 <a name="slew-option-_0028_002dx_0029"></a>
897 <h4 class="subsection">1.1.27 slew option (-x)</h4>
898 <a name="index-ntpd_002dslew"></a>
900 <p>This is the “slew up to 600 seconds” option.
901 Normally, 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.
902 This option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually.
903 Note: 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.
904 Thus, an adjustment as much as 600 s will take almost 14 days to complete.
905 This option can be used with the
912 configuration file directive for other options.
913 Note: The kernel time discipline is disabled with this option.
915 <a name="ntpd-usepcc"></a>
918 Next: <a href="#ntpd-pccfreq" accesskey="n" rel="next">ntpd pccfreq</a>, Previous: <a href="#ntpd-slew" accesskey="p" rel="prev">ntpd slew</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
920 <a name="usepcc-option"></a>
921 <h4 class="subsection">1.1.28 usepcc option</h4>
922 <a name="index-ntpd_002dusepcc"></a>
924 <p>This is the “use cpu cycle counter (windows only)” option.
926 <p>This option has some usage constraints. It:
928 <li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
931 <p>Attempt to substitute the CPU counter for <code>QueryPerformanceCounter</code>.
932 The CPU counter and <code>QueryPerformanceCounter</code> are compared, and if
933 they have the same frequency, the CPU counter (RDTSC on x86) is
934 used directly, saving the overhead of a system call.
936 <a name="ntpd-pccfreq"></a>
939 Next: <a href="#ntpd-mdns" accesskey="n" rel="next">ntpd mdns</a>, Previous: <a href="#ntpd-usepcc" accesskey="p" rel="prev">ntpd usepcc</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
941 <a name="pccfreq-option"></a>
942 <h4 class="subsection">1.1.29 pccfreq option</h4>
943 <a name="index-ntpd_002dpccfreq"></a>
945 <p>This is the “force cpu cycle counter use (windows only)” option.
946 This option takes a string argument.
948 <p>This option has some usage constraints. It:
950 <li> must be compiled in by defining <code>SYS_WINNT</code> during the compilation.
953 <p>Force substitution the CPU counter for <code>QueryPerformanceCounter</code>.
954 The CPU counter (RDTSC on x86) is used unconditionally with the
955 given frequency (in Hz).
957 <a name="ntpd-mdns"></a>
960 Next: <a href="#ntpd-config" accesskey="n" rel="next">ntpd config</a>, Previous: <a href="#ntpd-pccfreq" accesskey="p" rel="prev">ntpd pccfreq</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
962 <a name="mdns-option-_0028_002dm_0029"></a>
963 <h4 class="subsection">1.1.30 mdns option (-m)</h4>
964 <a name="index-ntpd_002dmdns"></a>
966 <p>This is the “register with mdns as a ntp server” option.
968 <p>This option has some usage constraints. It:
970 <li> must be compiled in by defining <code>HAVE_DNSREGISTRATION</code> during the compilation.
973 <p>Registers as an NTP server with the local mDNS server which allows
974 the server to be discovered via mDNS client lookup.
978 <a name="ntpd-config"></a>
981 Next: <a href="#ntpd-exit-status" accesskey="n" rel="next">ntpd exit status</a>, Previous: <a href="#ntpd-mdns" accesskey="p" rel="prev">ntpd mdns</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
983 <a name="presetting_002fconfiguring-ntpd"></a>
984 <h4 class="subsection">1.1.31 presetting/configuring ntpd</h4>
986 <p>Any option that is not marked as <i>not presettable</i> may be preset by
987 loading values from environment variables named <code>NTPD</code> and <code>NTPD_<OPTION_NAME></code>. <code><OPTION_NAME></code> must be one of
988 the options listed above in upper case and segmented with underscores.
989 The <code>NTPD</code> variable will be tokenized and parsed like
990 the command line. The remaining variables are tested for existence and their
991 values are treated like option arguments.
994 <p>The command line options relating to configuration and/or usage help are:
996 <a name="version-_0028_002d_0029"></a>
997 <h4 class="subsubheading">version (-)</h4>
999 <p>Print the program version to standard out, optionally with licensing
1000 information, then exit 0. The optional argument specifies how much licensing
1001 detail to provide. The default is to print just the version. The licensing infomation may be selected with an option argument.
1002 Only the first letter of the argument is examined:
1004 <dl compact="compact">
1005 <dt>‘<samp>version</samp>’</dt>
1006 <dd><p>Only print the version. This is the default.
1008 <dt>‘<samp>copyright</samp>’</dt>
1009 <dd><p>Name the copyright usage licensing terms.
1011 <dt>‘<samp>verbose</samp>’</dt>
1012 <dd><p>Print the full copyright usage licensing terms.
1017 <a name="ntpd-exit-status"></a>
1018 <div class="header">
1020 Next: <a href="#ntpd-Usage" accesskey="n" rel="next">ntpd Usage</a>, Previous: <a href="#ntpd-config" accesskey="p" rel="prev">ntpd config</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
1022 <a name="ntpd-exit-status-1"></a>
1023 <h4 class="subsection">1.1.32 ntpd exit status</h4>
1025 <p>One of the following exit values will be returned:
1026 </p><dl compact="compact">
1027 <dt>‘<samp>0 (EXIT_SUCCESS)</samp>’</dt>
1028 <dd><p>Successful program execution.
1030 <dt>‘<samp>1 (EXIT_FAILURE)</samp>’</dt>
1031 <dd><p>The operation failed or the command syntax was not valid.
1035 <a name="ntpd-Usage"></a>
1036 <div class="header">
1038 Next: <a href="#ntpd-Files" accesskey="n" rel="next">ntpd Files</a>, Previous: <a href="#ntpd-exit-status" accesskey="p" rel="prev">ntpd exit status</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
1040 <a name="ntpd-Usage-1"></a>
1041 <h4 class="subsection">1.1.33 ntpd Usage</h4>
1043 <a name="ntpd-Files"></a>
1044 <div class="header">
1046 Next: <a href="#ntpd-See-Also" accesskey="n" rel="next">ntpd See Also</a>, Previous: <a href="#ntpd-Usage" accesskey="p" rel="prev">ntpd Usage</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
1048 <a name="ntpd-Files-1"></a>
1049 <h4 class="subsection">1.1.34 ntpd Files</h4>
1051 <a name="ntpd-See-Also"></a>
1052 <div class="header">
1054 Next: <a href="#ntpd-Bugs" accesskey="n" rel="next">ntpd Bugs</a>, Previous: <a href="#ntpd-Files" accesskey="p" rel="prev">ntpd Files</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
1056 <a name="ntpd-See-Also-1"></a>
1057 <h4 class="subsection">1.1.35 ntpd See Also</h4>
1059 <a name="ntpd-Bugs"></a>
1060 <div class="header">
1062 Next: <a href="#ntpd-Notes" accesskey="n" rel="next">ntpd Notes</a>, Previous: <a href="#ntpd-See-Also" accesskey="p" rel="prev">ntpd See Also</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
1064 <a name="ntpd-Bugs-1"></a>
1065 <h4 class="subsection">1.1.36 ntpd Bugs</h4>
1067 <a name="ntpd-Notes"></a>
1068 <div class="header">
1070 Previous: <a href="#ntpd-Bugs" accesskey="p" rel="prev">ntpd Bugs</a>, Up: <a href="#ntpd-Invocation" accesskey="u" rel="up">ntpd Invocation</a> </p>
1072 <a name="ntpd-Notes-1"></a>
1073 <h4 class="subsection">1.1.37 ntpd Notes</h4>
1076 <a name="Usage"></a>
1077 <div class="header">
1079 Previous: <a href="#ntpd-Invocation" accesskey="p" rel="prev">ntpd Invocation</a>, Up: <a href="#ntpd-Description" accesskey="u" rel="up">ntpd Description</a> </p>
1081 <a name="Usage-1"></a>
1082 <h3 class="section">1.2 Usage</h3>
1085 <thead><tr><th width="23%">What</th><th width="23%">Default</th><th width="5%">Flag</th><th width="15%">Option</th></tr></thead>
1086 <tr><td width="23%">configuration file</td><td width="23%"><code>/etc/ntp.conf</code></td><td width="5%"><code>-c</code></td><td width="15%"><code>conffile</code></td></tr>
1087 <tr><td width="23%">frequency file</td><td width="23%">none</td><td width="5%"><code>-f</code></td><td width="15%"><code>driftfile</code></td></tr>
1088 <tr><td width="23%">leapseconds file</td><td width="23%">none</td><td width="5%"></td><td width="15%"><code>leapfile</code></td></tr>
1089 <tr><td width="23%">process ID file</td><td width="23%">none</td><td width="5%"><code>-p</code></td><td width="15%"><code>pidfile</code></td></tr>
1090 <tr><td width="23%">log file</td><td width="23%">system log</td><td width="5%"><code>-l</code></td><td width="15%"><code>logfile</code></td></tr>
1091 <tr><td width="23%">include file</td><td width="23%">none</td><td width="5%">none</td><td width="15%"><code>includefile</code></td></tr>
1092 <tr><td width="23%">statistics path</td><td width="23%"><code>/var/NTP</code></td><td width="5%"><code>-s</code></td><td width="15%"><code>statsdir</code></td></tr>
1093 <tr><td width="23%">keys path</td><td width="23%"><code>/usr/local/etc</code></td><td width="5%"><code>-k</code></td><td width="15%"><code>keysdir</code></td></tr>