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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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Windows Server 2012 time keeps setting itself 12 minutes ahead

Our Active Directory server has a problem whereby the time keeps setting itself 12 minutes ahead of the real time. This causes authentication issues on the network. I have tried syncing to an external NTP service with the following: w32tm /config…
Aaron Cunnington
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Nagios - check_ntp_time - Offset Unknown

I have a local NTP server running on the subnet to keep other subnet nodes in sync, without every node syncing with upstream servers. But, while implementing the check_ntp_time plugin for Nagios I am noticing a frustrating issue, where nagios keeps…
Mike Purcell
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hyper-v server time sync source - PDC / external NTP?

The environement: 10 Hyper-V hosts, all AD joined a lot of VMs AD joined and some not some AD DCs including PDC as Guests What You think is the best approach to time sync a hyper-v farm with AD controllers as guests ? I got 2 plans :) what would…
Bartłomiej Zarzecki
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Is it viable to use w32tm /stripchart to judge time variance of two Windows hosts from each other? A better way to discover two host's time variance?

Is it viable to use w32tm.exe's option stripchart to judge the time variance of two hosts (within a very small margin of error)? Note that w32tm.exe's stripchart function is separate than the algorithm used by the Windows Time service itself. If…
brandeded
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Hosting an NTP server on a standalone network

I have a LAN that is not connected to the internet, and I am trying to sychronize all the machines, Windows and Linux, to an NTP server. All I've been able to find is setting up an NTP client with an internet NTP server. How can I setup my own…
cdated
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ESXi VM NTP Server

We need to setup an internal NTP server. Because this server will pretty much ONLY be a time server I was thinking of just creating a VM for it. However, Googling around it appears that there there might be serious clock drifting issues with VM…
jstorch
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Does installing NTP mean I'm installing an NTP server?

Reading this: What are the limits of running NTP servers in virtual machines? (2010) And this: https://github.com/geerlingguy/ansible-role-ntp I'm not sure what exactly I'm installing. Especially if I'm installing inside a VM. I'm reading that VMs…
KoenDG
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Why does my ntpd not work?

Edit I've tried all your suggestions, but it seems that ntpd just refuse to synchronize to the server. [vivs@peter-centos ~]$ /usr/sbin/ntpq -np remote refid st t when poll reach delay offset …
faceclean
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Verify internal NTP server is sending the correct time?

I have two NTP stratum 3 servers running and wanted to create a simple check that I could tell if either of the servers time drifted and alert that it's not synced properly with the public stratum 2 servers. My first thought was to pull time from…
krizzo
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How do I configure a Unix system to run on TAI time?

I want to configure a Unix system to run on International Atomic Time (TAI) in order to be able to see the year-end leap second properly reported as 2016-12-31 23:59:60. I know this will cause the system's timestamps to be incompatible with POSIX…
Diomidis Spinellis
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systemd-timesyncd: how to check and set network time synchronization interval?

I see only one event of time synchronization in log. It occurs at boot: systemd-timesyncd[690]: Synchronized to time server 188.112.42.5:123 (2.debian.pool.ntp.org). How to force periodic time updates? How to check what is the current interval? I…
ardabro
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Chrony doesn't appear to be syncing with the servers I've specified

I have set Chrony to sync with 4 NTP servers (config file below). When I run chronyc tracking and chronyc sources, it looks like the servers my machine is connecting to for NTP are not correct. I'd expect to see the list of servers I specify in the…
Chris Williams
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NTP: How to establish redundant solution for NTP servers?

In my company's infrastructure there are 5 data centers in remote locations. In each remote location, there's a pair of servers which hold DNS and NTP services and are configured on each one of the servers in that location to get DNS and NTP calls…
Itai Ganot
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How to fix time on NTP server with a lot of machines synchronized by it

I have one NTP server which has a wrong time setting which are 7 hours in the future (timezone was changed after machine shipment, but not the time). The server itself is not synchronized, but only has its local clock. On this server >10 clients…
Rick-Rainer Ludwig
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ntpd keeps adding local servers while being told not to

I'm configuring ntp inside a corporate network. I've done restrict default ignore restrict -6 default ignore and listed servers explicitly (I'm using public servers from pool.ntp.org). I also didn't enable broadcastclient. After a while, ntpq -p…
loopbackbee
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