Date: Fri, 17 Nov 2017 11:18:49 +0100 From: Raimund Sacherer <raimund.sacherer@logitravel.com> To: vogelke@pobox.com Cc: freebsd-questions@freebsd.org Subject: Re: Another 11.1-RELEASE install minor annoyance (ntpd) Message-ID: <CAAG%2B3oWTYW1vB1ihE=XrZwVEwmCK63JwbFYk37LPSi4kBVM6pw@mail.gmail.com> In-Reply-To: <20171012204455.GA10740@bsd118.wpafb.af.mil> References: <CACArijC-urzJYRuA9TanUjan5EFRcStMr=rQ%2BgmcRD_KO6gzAA@mail.gmail.com> <3967.1507825257@segfault.tristatelogic.com> <CACArijD0LgS731K7Xdh%2BOcQ1Cicx0k9yzBKiVniW74b2WosmUA@mail.gmail.com> <20171012204455.GA10740@bsd118.wpafb.af.mil>
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> Second, ntpd, internally, is built on a phase-locked loop, which is > supposed to stabilize its time corrections in the face of jitter and > other > bad things out in the real world. Like anything based on a negative > feedback loop, however, it can be destablized with certain inputs. > Giving ntpd two or more servers is a pretty good way to destabilize its > PLL in the real, non-ideal world we find on the modern Internet. > To anyone considering flaming me, please read this first: > > http://queue.acm.org/detail.cfm?id=3D1773943 > > At minimum, read the section "One server is enough". The bit on PLLs > about halfway down is also directly relevant. > > Hello, I read the article, but I am astonished, I am by no means any expert in time, but the article is from a lot of years back and I was questioning what was written there. Is ntp really working like they say, jumping from one time server to another? I thought it to be some sort of consensus based protocoll where it queries a couple of servers, boots off servers which are way off, and creates a consensus on the remaining ones? I would love if someone knowledgable how the protocol works could say if it really is better to have one server instead of a couple more? If so, than why most default configuration (like ubuntu) have 4 or 5 servers configured? The article also read a bit as promotional vehicle for radclock, but checking out radclocks webpage, their last modification seems to be 2015, and they still claim the "we like to have ready in 2 years" statement they had in 2008 .... Best Ray > -- > Karl Vogel I don't speak for the USAF or my company > > Teenage girl creates sustainable, renewable algae biofuel under her bed > --Extreme Tech headline, 19 March 201= 3 > _______________________________________________ > freebsd-questions@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-questions > To unsubscribe, send any mail to "freebsd-questions- > unsubscribe@freebsd.org" > --=20 Raimund Sacherer Head of Tele-Communications Logitravel Group Edificio Logitravel Parcela 3B, Parc Bit Ctra. Palma - Valldemossa km 7,4 07121 Palma de Mallorca Tel 971 080 125 - 0145 Fax 971 213 495 L.O. 15/1999: Sus datos personales est=C3=A1n incorporados a un fichero de = la entidad remitente para el mantenimiento de las comunicaciones rec=C3=ADproc= as por cuestiones derivadas de su actividad. Para acceder, cancelar o rectificar su informaci=C3=B3n personal, as=C3=AD como para oponerse a su tratamiento, puede enviar un correo electr=C3=B3nico a privacy@logitravelgroup.com o dirigirse por escrito al domicilio que aparece en la firma de este correo. Este mensaje y sus documentos adjuntos son confidenciales. Si usted no es el destinatario, por favor p=C3=B3ngalo = en conocimiento del remitente y elimine esta comunicaci=C3=B3n y los documento= s adjuntos, sin reproducir ni comunicar sus contenidos. La transmisi=C3=B3n d= e correo electr=C3=B3nico no garantiza que sea seguro o libre de error, por l= o que declinamos cualquier responsabilidad al respecto. L.O. 15/1999: Your personal data are stored in a file of the sender to maintain reciprocal communications for issues arising from its business entity. To access, edit or delete your personal information and to object to your treatment, you can send an email to privacy@logitravelgroup.com or write to the address on the signature of this mail. This message and any attachments are confidential. If you are not the intended recipient, please put it known to the sender and delete this communication and attachments, without reproducing or communicate their contents. Email transmission not guaranteed to be secure or error-free, so disclaim any responsibility on it.
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