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Questions tagged [ntp]

NTP stands for Network Time Protocol, and it is an Internet protocol used to synchronize the clocks of computers to some time reference.

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How should nftables rules using hostnames be rewritten to deal with multiple addresses?

I have this nftables rule: ip daddr { "0.nixos.pool.ntp.org", "1.nixos.pool.ntp.org", "2.nixos.pool.ntp.org", "3.nixos.pool.ntp.org" } udp dport ntp accept comment "Allow NTP traffic for system time" The goal is to allow NTP traffic from a host…
Jean-Paul Calderone
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How to do proper VPS timekeeping?

I'm configuring a VPS to log some time-series online data and I notice that the time is off. I'd like to have better than 10 second precision on this. I read somewhere that VPS timekeeping is different than on native (x86) systems because the error…
Xunie
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ntp_gettime() returns code 5

I'm trying syncronize clock on ubuntu server with commands: $sudo apt-get install ntp $sudo service ntp stop $sudo ntpd -gq $sudo service ntp start But it anyway gives me: $sudo ntptime ntp_gettime() returns code 5 (ERROR) time…
Nikita
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After hours of running, NTP stops working

My NTP servers work great for a couple hours, then they stop working and show "reach: 0" for all hosts, like so: remote refid st t when poll reach delay offset …
Isabell Cowan
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WIndows 2016: How to force time sync after reverting to a snapshot?

Using vmware vsphere server 6.0.0 with a VM running Windows 2016. I have Windows set up to sync time with time.nist.gov. The machine is using UTC time zone. After restoring to a snapshot the time does not update for a while (if ever?). I've tried…
Skrymsli
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Is PTP really more precise than NTP? If so, why?

I have read quite a bit about NTP and PTP time keeping protocols. While many sources claim that PTP is more precise than NTP for that type of granularity - the reason is not as clear. Why can't NTP be just as accurate if a stratum 0 reference clock…
Palace Chan
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winter and summer time switch without a break in the timeline

Does anybody know if there is a possibility to switch from summer- to wintertime without an interruption in the timeline. I have an application that logs transactions with a timestamp. The problem is, that I must not have overlapping timestamps. If…
user24143
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Creating a badly behaved NTP server for testing

I'm trying to test behaviour of a server that's configured with a badly behaved NTP server, such as one that's drifting wildly or reporting times that jump around excessively. I've found lots of advice for setting up a good NTP system, but how can I…
me_and
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NTP: Linux client won't sync with Win7 server running ntpd ( not w32time)

We have a 'bot with a Linux host running on an internal network connected only to a Win7 host. The Win7 host has internet access, but the Linux host does not. (historical reasons) When I load NTPD from Meinberg on the win7 box it syncs with network…
John P. Fisher
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NTP Server with Authentication on Windows System

Can we configure an NTP Server with authentication on Windows OS, i.e Windows Server 2008 R2 Standard or Windows 7 operating system? I need to sync time securely for my Cisco switch and a router so that is the reason I need to configure secure the…
Param
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Building NTP with OpenSSL

I am trying to build the latest version of NTP (4.2.8p3 released on 2015/06/29) with OpenSSL support. I can definitely build NTP but when I try to use ntp-keygen to create a new certificate it tells me that the parameters are unknown. I use this…
Guillaume B
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Does NT5DS time synchronization have any place in a mixed Windows / Linux environment?

I am working on a plan towards overhauling how time synchronization is handled on our network. Currently our network is predominantly Windows-based, in a fairly standard AD domain broken up into various sites. However we are starting to utilize…
Tony Mitera
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Time synchronization and scheduled tasks

If NTP runs at 10:59:55, and fixes the time to 11:00:13, does chron run the 11:00:00, and *:00:00 tasks, or are they skipped? Alternately, if NTP runs at 11:00:00 and fixes the time to 10:59:48, do these tasks run twice? If they are skipped, what…
Adam Davis
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Windows NTP server with Linux clients

Has anyone got any experience syncing Linux (specifically Red Hat) to a Windows NTP server? Currently our Windows server is syncing to an stratum 1 server on the internet but the Linux boxes refuse to acknowledge it as a good time source. Having…
Chris Edgington
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Usefulness of a new stratum-1 NTP server

A physicist I know that works in a government institution recently commented that they have a cesium clock, and they were considering the possibility of setting up a public stratum 1 NTP server attached to it. However they (and I) were wondering…
Mauricio Scheffer
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