1@node ntpd Invocation
2@section Invoking ntpd
3@pindex ntpd
4@cindex NTP daemon program
5@ignore
6# 
7# EDIT THIS FILE WITH CAUTION  (ntpd-opts.texi)
8# 
9# It has been AutoGen-ed  Tuesday December  8, 2009 at 08:13:12 AM EST
10# From the definitions    ntpd-opts.def
11# and the template file   aginfo.tpl
12@end ignore
13This program has no explanation.
14
15
16
17This section was generated by @strong{AutoGen},
18the aginfo template and the option descriptions for the @command{ntpd} program.  It documents the ntpd usage text and option meanings.
19
20This software is released under a specialized copyright license.
21
22@menu
23* ntpd usage::                  ntpd usage help (-?)
24* ntpd authnoreq::              authnoreq option (-A)
25* ntpd authreq::                authreq option (-a)
26* ntpd bcastsync::              bcastsync option (-b)
27* ntpd configfile::             configfile option (-c)
28* ntpd debug-level::            debug-level option (-d)
29* ntpd driftfile::              driftfile option (-f)
30* ntpd dvar::                   dvar option (-V)
31* ntpd interface::              interface option (-I)
32* ntpd ipv4::                   ipv4 option (-4)
33* ntpd ipv6::                   ipv6 option (-6)
34* ntpd jaildir::                jaildir option (-i)
35* ntpd keyfile::                keyfile option (-k)
36* ntpd logfile::                logfile option (-l)
37* ntpd modifymmtimer::          modifymmtimer option (-M)
38* ntpd nice::                   nice option (-N)
39* ntpd nofork::                 nofork option (-n)
40* ntpd novirtualips::           novirtualips option (-L)
41* ntpd panicgate::              panicgate option (-g)
42* ntpd pidfile::                pidfile option (-p)
43* ntpd priority::               priority option (-P)
44* ntpd propagationdelay::       propagationdelay option (-r)
45* ntpd quit::                   quit option (-q)
46* ntpd set-debug-level::        set-debug-level option (-D)
47* ntpd slew::                   slew option (-x)
48* ntpd statsdir::               statsdir option (-s)
49* ntpd trustedkey::             trustedkey option (-t)
50* ntpd updateinterval::         updateinterval option (-U)
51* ntpd user::                   user option (-u)
52* ntpd var::                    var option (-v)
53@end menu
54
55@node ntpd usage
56@subsection ntpd usage help (-?)
57@cindex ntpd usage
58
59This is the automatically generated usage text for ntpd:
60
61@exampleindent 0
62@example
63ntpd - NTP daemon program - Ver. 4.2.5p247-RC
64USAGE:  ntpd [ -<flag> [<val>] | --<name>[@{=| @}<val>] ]...
65  Flg Arg Option-Name    Description
66   -4 no  ipv4           Force IPv4 DNS name resolution
67                                - prohibits these options:
68                                ipv6
69   -6 no  ipv6           Force IPv6 DNS name resolution
70                                - prohibits these options:
71                                ipv4
72   -a no  authreq        Require crypto authentication
73                                - prohibits these options:
74                                authnoreq
75   -A no  authnoreq      Do not require crypto authentication
76                                - prohibits these options:
77                                authreq
78   -b no  bcastsync      Allow us to sync to broadcast servers
79   -c Str configfile     configuration file name
80   -d no  debug-level    Increase output debug message level
81                                - may appear multiple times
82   -D Str set-debug-level Set the output debug message level
83                                - may appear multiple times
84   -f Str driftfile      frequency drift file name
85   -g no  panicgate      Allow the first adjustment to be Big
86                                - may appear multiple times
87   -i --- jaildir        built without --enable-clockctl or --enable-linuxcaps
88   -I Str interface      Listen on an interface name or address
89                                - may appear multiple times
90   -k Str keyfile        path to symmetric keys
91   -l Str logfile        path to the log file
92   -L no  novirtualips   Do not listen to virtual interfaces
93   -n no  nofork         Do not fork
94   -N no  nice           Run at high priority
95   -p Str pidfile        path to the PID file
96   -P Num priority       Process priority
97   -q no  quit           Set the time and quit
98   -r Str propagationdelay Broadcast/propagation delay
99      Str saveconfigquit Save parsed configuration and quit
100   -s Str statsdir       Statistics file location
101   -t Str trustedkey     Trusted key number
102                                - may appear multiple times
103   -u --- user           built without --enable-clockctl or --enable-linuxcaps
104   -U Num updateinterval interval in seconds between scans for new or dropped interfaces
105      Str var            make ARG an ntp variable (RW)
106                                - may appear multiple times
107      Str dvar           make ARG an ntp variable (RW|DEF)
108                                - may appear multiple times
109   -x no  slew           Slew up to 600 seconds
110      opt version        Output version information and exit
111   -? no  help           Display extended usage information and exit
112   -! no  more-help      Extended usage information passed thru pager
113
114Options are specified by doubled hyphens and their name
115or by a single hyphen and the flag character.
116
117The following option preset mechanisms are supported:
118 - examining environment variables named NTPD_*
119
120
121
122please send bug reports to:  http://bugs.ntp.org, bugs@@ntp.org
123@end example
124@exampleindent 4
125
126@node ntpd ipv4
127@subsection ipv4 option (-4)
128@cindex ntpd-ipv4
129
130This is the ``force ipv4 dns name resolution'' option.
131
132This option has some usage constraints.  It:
133@itemize @bullet
134@item
135is a member of the ipv4 class of options.
136@end itemize
137
138Force DNS resolution of following host names on the command line
139to the IPv4 namespace.
140
141@node ntpd ipv6
142@subsection ipv6 option (-6)
143@cindex ntpd-ipv6
144
145This is the ``force ipv6 dns name resolution'' option.
146
147This option has some usage constraints.  It:
148@itemize @bullet
149@item
150is a member of the ipv4 class of options.
151@end itemize
152
153Force DNS resolution of following host names on the command line
154to the IPv6 namespace.
155
156@node ntpd authreq
157@subsection authreq option (-a)
158@cindex ntpd-authreq
159
160This is the ``require crypto authentication'' option.
161
162This option has some usage constraints.  It:
163@itemize @bullet
164@item
165must not appear in combination with any of the following options:
166authnoreq.
167@end itemize
168
169Require cryptographic authentication for broadcast client,
170multicast client and symmetric passive associations.
171This is the default.
172
173@node ntpd authnoreq
174@subsection authnoreq option (-A)
175@cindex ntpd-authnoreq
176
177This is the ``do not require crypto authentication'' option.
178
179This option has some usage constraints.  It:
180@itemize @bullet
181@item
182must not appear in combination with any of the following options:
183authreq.
184@end itemize
185
186Do not require cryptographic authentication for broadcast client,
187multicast client and symmetric passive associations.
188This is almost never a good idea.
189
190@node ntpd bcastsync
191@subsection bcastsync option (-b)
192@cindex ntpd-bcastsync
193
194This is the ``allow us to sync to broadcast servers'' option.
195
196
197@node ntpd configfile
198@subsection configfile option (-c)
199@cindex ntpd-configfile
200
201This is the ``configuration file name'' option.
202The name and path of the configuration file,
203/etc/ntp.conf
204by default.
205
206@node ntpd debug-level
207@subsection debug-level option (-d)
208@cindex ntpd-debug-level
209
210This is the ``increase output debug message level'' option.
211
212This option has some usage constraints.  It:
213@itemize @bullet
214@item
215may appear an unlimited number of times.
216@item
217must be compiled in by defining @code{DEBUG} during the compilation.
218@end itemize
219
220Increase the debugging message output level.
221
222@node ntpd set-debug-level
223@subsection set-debug-level option (-D)
224@cindex ntpd-set-debug-level
225
226This is the ``set the output debug message level'' option.
227
228This option has some usage constraints.  It:
229@itemize @bullet
230@item
231may appear an unlimited number of times.
232@item
233must be compiled in by defining @code{DEBUG} during the compilation.
234@end itemize
235
236Set the output debugging level.  Can be supplied multiple times,
237but each overrides the previous value(s).
238
239@node ntpd driftfile
240@subsection driftfile option (-f)
241@cindex ntpd-driftfile
242
243This is the ``frequency drift file name'' option.
244The name and path of the frequency file,
245/etc/ntp.drift
246by default.
247This is the same operation as the
248driftfile driftfile
249configuration specification in the 
250/etc/ntp.conf
251file.
252
253@node ntpd panicgate
254@subsection panicgate option (-g)
255@cindex ntpd-panicgate
256
257This is the ``allow the first adjustment to be big'' option.
258Normally,
259ntpd
260exits 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,
261ntpd
262will exit with a message to the system log. This option can be used with the
263-q
264and
265-x
266options.
267See the
268tinker
269configuration file directive for other options.
270
271@node ntpd jaildir
272@subsection jaildir option (-i)
273@cindex ntpd-jaildir
274
275This is the ``jail directory'' option.
276Chroot the server to the directory
277jaildir
278.
279This option also implies that the server attempts to drop root privileges at startup (otherwise, chroot gives very little additional security), and it is only available if the OS supports to run the server without full root privileges.
280You may need to also specify a
281-u
282option.
283
284@node ntpd interface
285@subsection interface option (-I)
286@cindex ntpd-interface
287
288This is the ``listen on interface'' option.
289
290This option has some usage constraints.  It:
291@itemize @bullet
292@item
293may appear an unlimited number of times.
294@end itemize
295
296
297
298@node ntpd keyfile
299@subsection keyfile option (-k)
300@cindex ntpd-keyfile
301
302This is the ``path to symmetric keys'' option.
303Specify the name and path of the symmetric key file.
304/etc/ntp.keys
305is the default.
306This is the same operation as the
307keys keyfile
308configuration file directive.
309
310@node ntpd logfile
311@subsection logfile option (-l)
312@cindex ntpd-logfile
313
314This is the ``path to the log file'' option.
315Specify the name and path of the log file.
316The default is the system log file.
317This is the same operation as the
318logfile logfile
319configuration file directive.
320
321@node ntpd novirtualips
322@subsection novirtualips option (-L)
323@cindex ntpd-novirtualips
324
325This is the ``do not listen to virtual ips'' option.
326Do not listen to virtual IPs. The default is to listen.
327
328@node ntpd modifymmtimer
329@subsection modifymmtimer option (-M)
330@cindex ntpd-modifymmtimer
331
332This is the ``modify multimedia timer (windows only)'' option.
333
334This option has some usage constraints.  It:
335@itemize @bullet
336@item
337must be compiled in by defining @code{SYS_WINNT} during the compilation.
338@end itemize
339
340Set the Windows Multimedia Timer to highest resolution.
341
342@node ntpd nofork
343@subsection nofork option (-n)
344@cindex ntpd-nofork
345
346This is the ``do not fork'' option.
347
348
349@node ntpd nice
350@subsection nice option (-N)
351@cindex ntpd-nice
352
353This is the ``run at high priority'' option.
354To the extent permitted by the operating system, run
355ntpd
356at the highest priority.
357
358@node ntpd pidfile
359@subsection pidfile option (-p)
360@cindex ntpd-pidfile
361
362This is the ``path to the pid file'' option.
363Specify the name and path of the file used to record
364ntpd's
365process ID.
366This is the same operation as the
367pidfile pidfile
368configuration file directive.
369
370@node ntpd priority
371@subsection priority option (-P)
372@cindex ntpd-priority
373
374This is the ``process priority'' option.
375To the extent permitted by the operating system, run
376ntpd
377at the specified
378sched_setscheduler(SCHED_FIFO)
379priority.
380
381@node ntpd quit
382@subsection quit option (-q)
383@cindex ntpd-quit
384
385This is the ``set the time and quit'' option.
386ntpd
387will exit just after the first time the clock is set. This behavior mimics that of the
388ntpdate
389program, which is to be retired.
390The
391-g
392and
393-x
394options can be used with this option.
395Note: The kernel time discipline is disabled with this option.
396
397@node ntpd propagationdelay
398@subsection propagationdelay option (-r)
399@cindex ntpd-propagationdelay
400
401This is the ``broadcast/propagation delay'' option.
402Specify 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.
403
404@node ntpd updateinterval
405@subsection updateinterval option (-U)
406@cindex ntpd-updateinterval
407
408This is the ``interval in seconds between scans for new or dropped interfaces'' option.
409Give the time in seconds between two scans for new or dropped interfaces.
410For systems with routing socket support the scans will be performed shortly after the interface change
411has been detected by the system.
412Use 0 to disable scanning.
413
414@node ntpd statsdir
415@subsection statsdir option (-s)
416@cindex ntpd-statsdir
417
418This is the ``statistics file location'' option.
419Specify the directory path for files created by the statistics facility.
420This is the same operation as the
421statsdir statsdir
422configuration file directive.
423
424@node ntpd trustedkey
425@subsection trustedkey option (-t)
426@cindex ntpd-trustedkey
427
428This is the ``trusted key number'' option.
429
430This option has some usage constraints.  It:
431@itemize @bullet
432@item
433may appear an unlimited number of times.
434@end itemize
435
436Add a key number to the trusted key list.
437
438@node ntpd user
439@subsection user option (-u)
440@cindex ntpd-user
441
442This is the ``run as userid (or userid:groupid)'' option.
443Specify a user, and optionally a group, to switch to.
444This option is only available if the OS supports to run the server without full root privileges.
445Currently, this option is supported under NetBSD (configure with
446--enable-clockctl
447) and Linux (configure with
448--enable-linuxcaps
449).
450
451@node ntpd var
452@subsection var option (-v)
453@cindex ntpd-var
454
455This is the ``make arg an ntp variable (rw)'' option.
456
457This option has some usage constraints.  It:
458@itemize @bullet
459@item
460may appear an unlimited number of times.
461@end itemize
462
463
464
465@node ntpd dvar
466@subsection dvar option (-V)
467@cindex ntpd-dvar
468
469This is the ``make arg an ntp variable (rw|def)'' option.
470
471This option has some usage constraints.  It:
472@itemize @bullet
473@item
474may appear an unlimited number of times.
475@end itemize
476
477
478
479@node ntpd slew
480@subsection slew option (-x)
481@cindex ntpd-slew
482
483This is the ``slew up to 600 seconds'' option.
484Normally, 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.
485This option sets the threshold to 600 s, which is well within the accuracy window to set the clock manually.
486Note: 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.
487Thus, an adjustment as much as 600 s will take almost 14 days to complete.
488This option can be used with the
489-g
490and
491-q
492options.
493See the
494tinker
495configuration file directive for other options.
496Note: The kernel time discipline is disabled with this option.
497