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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7
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2answers
273 views

DST Morocco, a way to trick NTP server

From several years Morocco have been using GMT without DST, in the past years, our government reactivated the use of DST. In the first years, the DST was a mess, different periods, starts, ends, so ...
-1
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0answers
46 views

What version of NTP is a Cisco product running [closed]

Just wondering if there was a way to check which Cisco model or IOS version had what NTP version on them. For clarification: I had checked this document. I had seen the version and assume it was the ...
0
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1answer
35 views

How to synchronize the time in Debian6 server? We have 30 min delay in our VMs

I can't have the correct time in our servers. We get always the same delay in the three of them (they are VM on the same server). We use ntp to have our date always synchronized· The main server ...
1
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2answers
37 views

Using public ntp servers for backup to local stratum 1 server

In my data centers, I have access to a stratum 1 server but I set up our servers to use ntp pool servers in addition to it. My main thinking was for backup in case our local server goes down but I am ...
1
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1answer
23 views

ntp synchronize time between peers

I am a newbie, so please bear with me. I have a network of around 10 computers for which I want to synchronize their time up to millisecond precision. The computers do not have Internet connection. ...
0
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1answer
1k views

Meinberg ntp for Windows - force more frequent updates?

I have a Windows VM that has time drift problems, and left to its own devices will drift by minutes per day. I know there are issues with time on VMs, but I was hoping using the Meinberg NTP service ...
5
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1answer
51 views

Tracing chain of NTP servers

For educational purposes I wanted to trace a chain of NTP servers, e.g. 0.de.pool.ntp.org back to a stratum 1 NTP server. How can I do this? I found ntptrace, but it doesn't work: /home/xyzdragon# ...
0
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1answer
83 views

ntpd: servers stuck on .INIT

I am trying to set up an NTP server for my local network, but ntpd refuses to sync with outer servers. # ntptrace localhost: stratum 16, offset 0.000000, synch distance 0.396285 # ntpq -pn ...
3
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2answers
235 views

NTP running, server time is wrong on VM

The server time was 7 hours off (instead of 10AM it was 3AM, even though date showed the correct timezone). The output for ntpq was: $ ntpq -p remote refid st t when poll reach ...
0
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1answer
61 views

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 ...
0
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0answers
30 views

Linux-NTP: What could cause high offset in some servers while all of them reside on the same network sigment and are configured the same?

I've installed a new NTP server and configured all Hadoop clients to use it. I've been told by the Hadoop Engineers that an offset of maximum 3 seconds is mandatory for the cluster to work properly. ...
1
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1answer
70 views

NTP can't synchronise

Okay so I tried syncing a windows clients clock to the ubuntu ntp server i just set up, but it gets a time out, when trying. So I went on the ubuntu server and looked at syslog: Apr 10 13:15:01 ...
0
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1answer
43 views

Best practices for time syncing a WS2012R2 domain controller that is a Hyper-V virtual machine?

What are generally the best practices for keeping time in a WS2012R2 domain controller? Right now I have left it as installation and honestly, there is no problem ("If it aint broke, don't fix it") ...
2
votes
2answers
12k views

What is my time source server 2003

Have just had a bit of an issue with our time setup after an issue with our PDC. Am on clear up duty now but am struggling with some 2003 servers. On server 2008 I can run w32tm /query /source and ...
0
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0answers
54 views

Time Zone keeps changing after sync with PDC in different site

Background: I have a single domain, running in 2 sites that is connected using Site-to-Site VPN. Site A is running in time zone 2:00+ UTC Site B is running in time zone 4:00+ UTC DCs are correctly ...
6
votes
6answers
10k views

Domain Controller time is incorrect

I have a domain controller running in VM on Hyper-V, the time seems to be steadily getting faster, over the X-mas period it's 5 faster, which seems odd! I know how to change the time and I belive we ...
1
vote
2answers
60 views

how to get a subset of NTP servers from *.pool.ntp.org?

I am doing some reliability tests and needed a list of NTP servers from fr.pool.ntp.org (or any other geographic or national pool). I queried the pool 100 times but only got 13 unique servers (out of ...
1
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3answers
484 views

Where do computers/servers in a Windows Domain get their time settings from? [duplicate]

I have 5 Windows Server 2012 servers and around 100 computers in our domain. Recently I noticed that the time on the servers and computers is around 30 seconds fast. Where do servers and computers ...
3
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2answers
3k views

How can I disable NTP in pfsense?

I am running my pfSense gateway in a ESXi server. right now the server gets its time from the NTP server specified in the general settings section of the WebGUI. I want to disable this so pfSense ...
0
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1answer
91 views

“NTP socket is in use” messages from ntpdate in syslog

In cron.log I can see that ntpdate is being triggered from a cron job which is running daily at 23:15 Mar 10 23:15:01 seitan /USR/SBIN/CRON[22407]: (root) CMD (/etc/network/if-up.d/ntpdate) But ...
0
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2answers
58 views

Can I configure a server to use a user port(>1023) for NTP?

Can a linux server be configured to use a high source port(above 1023) for NTP synchronization with a Stratum 1/2 server? Are there any disadvantages to doing this?
18
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3answers
274 views

Risk of starting NTP on database server?

I've heard rumors of bad things happening to database and mail servers if you change the system time while they are running. However, I'm having a hard time finding any concrete information on actual ...
0
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0answers
34 views

ntpd logging debug to ntpd.log

using ntpd 4.2.6p5 on redhat 6.5 How do I configure /etc/ntp.conf to generate debug messages to logfile? in /etc/ntp.conf I have logfile /var/log/ntpd.log but that only does very basic entries. ...
2
votes
1answer
1k views

Linux - NTP stopped working after recent update

A few days ago I had ntp setup on my network, and everything was running fine. One node was set to sync with upstream servers, and the rest of the nodes from the one set to sync upstream. Yesterday I ...
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1answer
78 views

date and sleep during leap second [closed]

Did you ever watch what happens with a sleep during a leap second or what date will show us? Most UNIX systems can handle a sleep with a fraction of a second and the date command can display ...
1
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0answers
220 views

Cisco SG300 SNTP servers always down

I'm trying to setup the SNTP of a new Cisco SG300-48 Switch in L3 mode. So far I have enabled the Main Clock Source (SNTP Servers) option (Administration -> Time Settings), set my time zone and ...
5
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5answers
2k views

NTP fudge network source stratum

Is it possible to configure ntpd to fudge the stratum level of a network source? Upon first glance, I thought the fudge directive could accomplish this, however after browsing the ntp.conf(5) man ...
2
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0answers
58 views

NTP offset warning when no NTP server is defined and NTP not running?

I just want to preface by saying that I am still learning linux and don't have too much experience with it. My job requires me to monitor an alert system for our clients hosts that are running our ...
0
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0answers
62 views

What causes ntpq refid CRYP when authentication is successful?

I have five servers that I'm configuring for production use based on a configuration we've recently tested. The servers are RHEL6 with NTP version 4.2.4p8@1.1612-o. Right now, though, I'm trying to ...
6
votes
2answers
474 views

What happens when DC cannot reach external time server?

We have a small Windows 2012 R2 domain with a single DC. The DC is advertising as a time server, and the clients are syncing just fine. The DC is getting its time from an external time server, and ...
5
votes
2answers
151 views

Proper NTP configuration for a few servers

I have about 20 Linux servers in a small network and I need their clocks decently close to each other (e.g. within 20msec). I've started with every one of them synced to europe.pool.ntp.org and the ...
0
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0answers
90 views

Why my server on Digital Ocean woke up with a wrong time?

Today one of my servers hosted on Digital Ocean (the only one hosted there) is reporting wrong time. It's two hours late. sudo dpkg-reconfigure tzdata # then I set up the timezone to Europe/Rome ...
2
votes
1answer
361 views

NTP: ntpdate to sync time between the PCs on a private network

I have two systems. One acts as Primary/Active and has Internet connection and gets time from NTP server. The second system is Secondary/Passive and has no connection to the external world. Primary ...
0
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0answers
33 views

Using RTC to synchronize ntpd when offline

I need a stable configuration, presumably using ntpd, to keep system clock as precise as possible. Background: I have several embedded devices (arm9) running linux (currently: 3.16.1 / debian 7.2) ...
1
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0answers
46 views

Server Migration 03 -> 12

I have run into a wall and out of ideas. Here's the situation. I have a client that has a old '03 DC with a 12 replicating the '03 server. It is out dated and has to many group policies and stuff it ...
0
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0answers
118 views

chronyd peer not syncing

I would like to configure two my servers as chronyd ntp peers. Both servers run on amazon ec2, one on centos 7, one on rhel 7 -what is minimal chrony peer configuration ? I cant use my other server ...
1
vote
1answer
88 views

Resync windows time after a long power outage

I'm facing the following situation: We have a computer with Windows 8 Standard Embedded. The machine is an industrial computer that doesn't have a CMOS Battery but a capacitor (a Gold Cap acting as a ...
1
vote
1answer
3k views

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 ...
0
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0answers
49 views

Ubuntu server is randomly having large time sync issues

It seems that randomly the time on my server will jump forward several hours. This happens randomly and the only way I've found to fix it is to manually force an NTP call. I don't see anything out of ...
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votes
2answers
59 views

What does this shell script mean? [closed]

#!/bin/bash /usr/sbin/ntpdate ntp.jst.mfeed.ad.jp I found such a script file,maybe it is used to confirm the time, can you explain it in detail?
5
votes
2answers
474 views

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 ...
4
votes
1answer
115 views

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 ...
3
votes
2answers
71 views

ntp authentication - MD5 - freeBSD

NTP claims to support md5 authentication. The docs I've found aren't clear enough for my level of luserhood. How would I go about using it, with a collection of freebsd clients, and a couple of ...
2
votes
2answers
208 views

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 ...
2
votes
1answer
143 views

NTP Version Check

How can I check other NTP server's NTP version without query the server? NTPv3 and NTPv4 network packet is different, and I know I can just catch the packet and analysis it when ntpd is doing sync. ...
7
votes
7answers
13k views

Hyper-V Machine drifts time all over, even with NTP

Resolved The problem was Hyper-V on that machine. I removed Hyper-V, installed VMware Server, ran the same VM. Time sync issues went away (< 100ms difference after a day). My setup is like this: ...
0
votes
1answer
185 views

NTP not sync the time continuously, Have to restart the service of NTP then it SYNC in Ubuntu

I am facing one problem. NTP server not sync the time automatically. If I change the the time of system then NTP server not able to correct it. After reboot the service of NTP it sync the time ...
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votes
1answer
158 views

How to update NTP-deamon on a Debian Squeeze (Proxmox 2.x)?

Because of security issue in NTP (CVE-2014-9295) I need to update NTP-deamon on a Debian Squeeze (it is the Proxmox 2.x installation). The problem is that it is a productional system and I can not ...
2
votes
1answer
20k views

How to change time source from “Local CMOS Clock” to “DC”

In a domain, I want to set DC as time server. To do that I use this command: w32tm /config /manualpeerlist:europe.pool.ntp.org /syncfromflags:manual /reliable:yes /update and w32tm /resync ...
5
votes
4answers
13k views

Setting up a local stratum 2 NTP server

I'm trying to setup NTP on a local network that has no (and never will) internet connection. The main priority is that the machines on the network are synced with each other, even if the time they're ...