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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Chronyc equivalent for ntpdate -q

According to ntpdate and chronyd man pages In ntpdate -q : Query only - don't set the clock. chronyd -q : When run in this mode, chronyd will set the system clock once and exit. It will not detach ...
Dexpras's user avatar
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Synchronizing time with only one NTP server

I have a linux machine on a network where the machine only has access to exactly one NTP server. After the time synchronization the status looks like this: [root@test ~]# ntpq -p remote ...
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Fake SNTP server for testing

I want to setup an SNTP server for testing purposes that can be set to any arbitrary value (for example testing DST behaviour of the device under test) serve only on eth1 on my RedHat Enterprise ...
Atilla Filiz's user avatar
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3 answers
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How to have ntpd serve only my local subnet

I have a few servers with public Internet IP addresses like A.B.C.x. One of my hosts (A.B.C.10) runs ntpd and I have it syncing it's time from europe.pool.ntp.org. Now I only want to allow hosts ...
ndemou's user avatar
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Nagios NTP, discarding peer

We're using nagios check_ntp_time for monitoring time on our servers. Unfortunately the service is flapping. And reporting a lot of false-positives. It happens everytime for random server in random ...
Michal Bryxí's user avatar
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NTP can't synchronise or find a suitable server

The problem I'm trying to solve is that NTP won't synchronize: $ sudo ntpstat unsynchronised time server re-starting polling server every 64 s Edit: Here's some ntpq output: $ sudo ntpq -c ...
Leo's user avatar
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Time not propagating to machines on Windows domain

We have a two-domain Active Directory forest: ourcompany.com at the root, and prod.ourcompany.com for production servers. Time is propagating properly through the root domain, but servers in the child ...
Richard Beier's user avatar
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Both my ntp servers are marked as falsetickers in the status [closed]

I have a linux box, set up with two ntp servers to sync. This box in case, was extremely out of sync (61 seconds) before it was forced sync. The following outputs are 1 hour after this sync. When ...
kurast's user avatar
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How often does openntpd update the time?

Neither the openntpd nor the ntpd.conf manpage have this information.
John Bachir's user avatar
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Cisco ASA5505 won't sync with NTP

Today I noticed that the clock my Cisco ASA 5505 firewall was running about 15 minutes late, which surprised me since I've set up the NTP client. My two NTP servers 10.10.0.1 and 10.10.0.2 are ...
Martijn Heemels's user avatar
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5 answers
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Does CentOS 5.4 properly handle leap seconds?

Apparently the IERS have announced a leap second due at midnight, June 30th this year. Is CentOS/RHEL 5.4 properly updated to support/transition along with updated NTP systems? I was under the ...
Mike B's user avatar
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How can I synchronize system time with a NTP server continuously?

Is there a linux service that can synchronize system time with a NTP server with a given interval, such as 1 minute, 1 hour or 1 day ? Is it a good practice to run utpdate in a cron tab? e.g. */10 * ...
auntyellow's user avatar
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1 answer
2k views

Time issues on the Network -- How to find the Root Cause

A number of application servers started erroring out in my domain. Troubleshooting led me to a missconfiguration of NTP. I fixed the issue, but I don't know how the issue arose in the first place. ...
Jeff's user avatar
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centOs : system time getting reset back to UTC after changing it using timedatectl

I have a Centos machine with version 7. I am trying to change the system time using the timedatectl command. The time gets changed but after a few seconds it gets reset back to it's original time. [...
user1851006's user avatar
1 vote
2 answers
6k views

Getting NTP to work on AWS without opening inbound port in security group

I have a private server on AWS that has no publicly open inbound ports. The only open port is SSH, and it's only accessible from other machines in the same subnet. This machine reads files from S3 ...
z0r's user avatar
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How to force locally isolated ntpd update time

Objective I had locally isolated hosts. I'd like them all have the same time. One takes role of the time server, other syncs with it as clients. All machines has sporadic uptime. They are powered ...
ayvango's user avatar
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Where can I see ntpd working status (log or message)

In my server the ntpd service is started but it does not seem to work. I can find nothing according to this ( Where are the ntpd log file located, and how can we configure the ntpd log file path? ) ...
auntyellow's user avatar
1 vote
2 answers
5k views

ntpdate wrong date

Hi all I have an ubuntu8 server where I have problems with date. My current date (Europe/Rome) is 9:35 If I do date print me 11:12:34 I have seen my ntp.conf is: server 0.ubuntu.pool.ntp.org ...
Alessandro Minoccheri's user avatar
1 vote
2 answers
2k views

RHEL 5 Hyper-V Guest - Cannot sync with NTP after kernel upgrade

I'm running a RHEL 5 (64 bit) guest on Microsoft Hyper-V. I've always had trouble with the clock getting way ahead of itself, which I was able to solve previously by adding divider=10 clocksource=...
user38939's user avatar
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Setting up NTP on 2 Linux boxes and one OpenBSD box

I have been tasked with getting an NTP client working on two Linux machines and an OpenBSD machine. The machines are arranged like this: NTPServer / \ / \ L1 L2 ...
Rich's user avatar
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3 answers
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Building a local time server

I am trying to install a time server on a local Ubuntu machine, so other servers in my network would sync with it. We have decided to install our own time server, rather than letting each server ...
Adam Matan's user avatar
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Using NTPD on OpenBSD to get time from Linux using portforwarding

This is a rehash of another question, now that I understand things a bit better. I have the following network set up: NTP 10.21.3.169 | \______________ | \ 10....
Rich's user avatar
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NTP time sync not working in a DOMU Centos 5.5 server

I have a Xen Centos 5.5 server with ntpd working in virtual server. NTP time sync seems not working. I have disabled any firewall. my grep -i ntpd /var/log/messages output: Apr 1 16:15:47 ...
Roberto's user avatar
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How to synchronize clocks on servers with no internet access?

I would like to synchronize the clocks on 10 Ubuntu 16.04 servers all with no internet access. Based on my internet searches, ntp does not seem to be designed for this. What is the easiest way to do ...
user551744's user avatar
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1 answer
526 views

Disconnect Local Clock from Domain Controller Clock

How can I disconnect my workstation clock from the domain controller? In other words, I do not want them synchronized.
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