327:. In December 2004, Darren Tucker, the principal developer on the portable branch of OpenNTPD, wrote a detailed response to Knowles, acknowledging some issues as valid, rejecting several others as unwarranted, and considering yet others as misleading. Among the more serious issues raised by Knowles was that OpenNTPD servers claimed to be stratum 1 servers. The issue had however already been fixed by the time of Tucker's response. In March 2005, Knowles acknowledged Tucker's response, and stated that he was "going to do everything to work with to get any remaining issues resolved". Additionally, the OpenBSD networking FAQ was expanded with a response to Knowles' initial criticism.
883:
295:$ grep ntpd /var/log/daemon.log | grep adjusting Aug 4 03:32:20 nikolai ntpd: adjusting local clock by -1.162333s Aug 4 03:36:08 nikolai ntpd: adjusting local clock by -1.023899s Aug 4 03:40:02 nikolai ntpd: adjusting local clock by -0.902637s Aug 4 03:43:43 nikolai ntpd: adjusting local clock by -0.789431s Aug 4 03:47:35 nikolai ntpd: adjusting local clock by -0.679320s Aug 4 03:50:45 nikolai ntpd: adjusting local clock by -0.605858s Aug 4 03:53:31 nikolai ntpd: adjusting local clock by -0.529821s
271:. In order to simplify the use of NTP, OpenNTPD implements a smaller set of functionalities than those available in other NTP daemons, such as that provided by the Network Time Protocol Project. The objective is to provide enough features to satisfy typical usage at the risk of unsuitability for esoteric or niche requirements. OpenNTPD is configured through the configuration file,
29:
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that increase accuracy in favour of code simplicity. The OpenNTPD project acknowledged the criticism, but stated that the lack of microsecond precision was a design tradeoff that benefited simplicity and security. The OpenNTPD design goals state the project's intent is to "each a reasonable accuracy"
246:
The development of OpenNTPD was motivated by a combination of issues with current NTP daemons: difficult configuration, complicated and difficult to audit code, and unsuitable licensing. OpenNTPD was designed to solve these problems and make time synchronization accessible to a wider userbase. After
259:, trivial to set up and administer, reasonably accurate, and light on system resources. As such, the design goals for OpenNTPD are: security, ease of use, and performance. Security in OpenNTPD is achieved by robust validity check in the network input path, use of bounded buffer operations via
234:, is developed as a child project which adds the portability code to the OpenBSD version and releases it separately. The portable version is developed by Brent Cook. The project developers receive some funding from the
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recommends that systems not implementing leap seconds be referenced to
International Atomic Time, or directly to GPS time signals. However, no current version of NTP (As of 2023) supports non-UTC time scales.
279:
to be used, and the set of servers from which the time will be synchronized. The accuracy of OpenNTPD is best-effort; the daemon attempts to be as accurate as possible but no specific accuracy is guaranteed.
319:
criticizing various aspects of OpenNTPD's implementation of the NTP protocol, as well as the split development model that the project employs, which is also used in the development of
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produced by the NTP Project (ntp.org). Internally, OpenNTPD does not maintain millisecond accuracy and can vary 50-200ms from "real" time because it omits a variety of
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346:. Care should be taken when using OpenNTPD as a higher-stratum source for other ntpd servers, or with high-resolution time requirements that reference
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to synchronize the local clock of a computer system with remote NTP servers. It is also able to act as an NTP server to NTP-compatible clients.
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In
September 2004, shortly after the release of OpenNTPD 3.6, ntp.org contributor Brad Knowles published an article entitled
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a period of development, OpenNTPD first appeared in OpenBSD 3.6. Its first release was announced on 2 November 2004.
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OpenNTPD is an attempt by the OpenBSD team to produce an NTP daemon implementation that is secure, simple to
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275:. A minimal number of options are offered: IP address or hostname on which OpenNTPD should listen, a
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The current OpenNTPD accuracy claim is, from the 2004 21C3 presentation, "typically 50 ms".
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OpenNTPD gradually adjusts the system clock, as seen here in the output of OpenNTPD running on a
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without sacrificing "secure design for getting that last nanosecond or obscure edge case."
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project, with further help by many authors. Its design goals include being secure (
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to mitigate the effects of possible security bugs exploiting the daemon through
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time signals. The 50-ms accuracy is also not typical of a high-stratum source.
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635:"FAQ 6.12.1: 'But OpenNTPD isn't as accurate as the ntp.org daemon!'"
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773:"FAQ: 6.12.2: 'Someone has claimed that OpenNTPD is 'harmful'!'"
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350:. Leap seconds are used in Coordinated Universal Time, but not
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OpenNTPD has been criticized as being less accurate than the
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210:OpenBSD NTP Daemon was initially developed by
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914:A paper explaining OpenNTPD by Henning Brauer
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620:. 26 May 2006. Retrieved 16 September 2006.
16:Implementation of the Network Time Protocol
946:
932:
717:"Response to OpenNTPd Considered Harmful"
367:Bureau International des Poids et Mesures
708:
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822:"Handling Leap Seconds the OpenBSD Way"
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506:The OpenBSD Project (1 November 2004).
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1202:OpenBSD software using the ISC license
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771:The OpenBSD Project (21 August 2006).
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633:The OpenBSD Project (21 August 2006).
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531:
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456:"openntpd-portable/openntpd-portable"
889:Free and open-source software portal
89:https://github.com/openntpd-portable
715:Tucker, Darren (12 December 2004).
684:Knowles, Brad (22 September 2004).
532:Brauer, Henning (2 November 2004).
33:"Saving the world again... on time"
13:
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580:Brauer, Henning (September 2004).
14:
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582:"Page 3: OpenNTPD – Design Goals"
22:OpenNTPD (aka OpenBSD NTP Daemon)
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852:United States Naval Observatory
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741:Knowles, Brad (12 March 2005).
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363:United States Naval Observatory
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63:6.8p1 / 7 December 2020
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1187:Network time-related software
686:"OpenNTPd Considered Harmful"
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919:OpenBSD FAQ: Using OpenNTPD
409:"OpenNTPD Portable Release"
317:OpenNTPd Considered Harmful
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721:Advogato: Blog for dtucker
431:"openssh/openssh-portable"
348:Coordinated Universal Time
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664:OpenNTPD authors (2004),
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804:"OpenBGPD and OpenNTPD"
534:"OpenNTPD 3.6 released"
277:timedelta sensor device
480:The OpenNTPD Project.
230:version, like that of
743:"Update: OpenNTPd..."
205:Network Time Protocol
65:; 3 years ago
783:on 24 September 2006
486:The OpenNTPD Project
269:privilege escalation
265:privilege separation
154:Time synchronization
858:on 24 December 2017
777:The OpenBSD Project
639:The OpenBSD Project
586:The OpenBSD Project
512:The OpenBSD Project
23:
1150:OpenBSD Foundation
746:Considered Harmful
690:Considered Harmful
672:, OpenNTPD project
645:on 5 February 2016
561:Unknown parameter
338:OpenNTPD (and the
236:OpenBSD Foundation
194:OpenBSD NTP Daemon
143:RFC 1305, RFC 5905
21:
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981:security features
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802:Brauer, Henning.
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203:implementing the
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808:quigon.bsws.de
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752:on 25 May 2006
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40:Developer(s)
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862:27 February
1181:Categories
393:9 December
388:"OpenNTPD"
374:References
309:algorithms
305:NTP daemon
95:Written in
84:Repository
70:2020-12-07
1059:OpenSMTPD
1054:OpenOSPFD
832:9 October
565:ignored (
411:. OpenBSD
299:Criticism
273:ntpd.conf
179:.openntpd
1106:Xenocara
1049:OpenNTPD
1044:OpenIKED
1039:OpenBGPD
1024:LibreSSL
670:OpenNTPD
365:and the
325:OpenBGPD
292:system:
228:portable
190:OpenNTPD
138:Standard
1197:OpenBSD
1081:sensors
1064:OpenSSH
971:OpenBSD
958:Project
956:OpenBSD
905:OpenBSD
899:ntpd(8)
666:"Goals"
614:OpenBSD
517:3 April
491:3 April
415:3 April
340:OpenBSD
321:OpenSSH
284:Example
261:strlcpy
242:History
232:OpenSSH
220:OpenBSD
196:) is a
172:Website
161:License
131:Solaris
115:FreeBSD
111:OpenBSD
68: (
48:Project
46:OpenBSD
1122:People
1074:pfsync
1029:mandoc
909:Manual
649:14 May
618:Manual
544:7 June
465:13 May
460:GitHub
440:13 May
435:GitHub
263:, and
201:daemon
119:NetBSD
1091:spamd
1086:sndio
1014:httpd
290:Linux
257:audit
251:Goals
127:macOS
123:Linux
1101:tmux
1096:sudo
1009:doas
1004:CARP
954:The
864:2019
834:2018
789:2006
758:2006
728:2006
702:2006
651:2020
593:2006
567:help
546:2014
519:2016
493:2016
467:2016
442:2016
417:2016
395:2020
361:The
323:and
214:and
198:Unix
181:.org
149:Type
44:The
1111:cwm
1019:fdm
999:bio
354:or
177:www
166:ISC
140:(s)
1183::
1069:PF
1034:mg
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