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Questions tagged [ntp]

The Network Time Protocol, is used to synchronize system clocks to precision time servers on the internet or locally connected devices such as a GPS.

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21 views

How can I change time in Kali linux which should be synchronized with internet India standard +5:30 timezone? [on hold]

I tried all commands: sudo timedatectl set-timezone Asia/Kolkata /usr/share/zoneinfo/Asia/Kolkata sudo ln -sf /usr/share/zoneinfo/Asia/Kolkata /etc/localtime sudo apt-get install ntp watch -n 1 "ntpq ...
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21 views

ntp to chrony config file mapping

I'm upgrading some sles11 boxes to sles15 and may need (or may not) need to know what some of the things we've got configured in our current instance of ntpd on the sles11 boxes does so I can find an ...
0
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1answer
15 views

ntpd.pid not getting generated even when ntpd is running in centos7

I have recently upgraded to centos7. I could observe that ntpd.pid is not generated when the ntpd service is started. Earlier, in centos 6, when we start the ntpd service the file ntpd.pid is ...
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2answers
33 views

Can I install both NTP server & NTP client on same machine (linux)?

Here's my use case : I have 2 independent networks & 3 servers. Server 1 & 2 are connected on Network 1 (172.24.xx.xxx) while Servers 2 & 3 are connected via network 2 (locally : 192.168....
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1answer
45 views

Cannot disable network time control (NTP)

I want to analyze some protocols (ARP, NDP, etc.) inside virtualbox (OS: Linux Mint 19.1 Tessa) using wireshark and tried to disable the "network time control"-synchronization. yuza@VirtualBox:~$ ...
2
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0answers
53 views

Alpine Linux Hangs During Boot at: “ successfully initialized wpa_supplicant”

I installed Alpine Linux on Intel Compute Stick with 32 Bit Atom Processor. After installation I followed the procedure laid out here for connecting to internet via wlan0 port: Connecting to a ...
5
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1answer
73 views

systemd: require NTP sync

What should I put in my unit file to ensure my service starts AFTER the time is set via ntp? I have a raspberry pi with a small python script that logs data to a SQL data base. Since the rpi doesn't ...
2
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0answers
63 views

ntp using ipv6 address instead of ipv4

I have a laptop running a version of Linux ( 3.12 ). I have ntpd installed and configured to sync with time.google.com. The problem I am having is if I am plugged into a network that only provides ...
1
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2answers
46 views

Check ntp server authentication with chronyd client

Is there an alternative for ntpq -c as, while using chronyd as client? While using ntpd as client, ntpq -c as provides details about authentication of client to server using keys.
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2answers
38 views

ntpd - Why/how is my network getting ntp synchronization while my ntpd is down on its provider?

I was under the impression that the ntpd service is required to be active for my network to be getting ntp data. All of my devices are synchronized to the server's IP, yet when I SSH into the server, ...
13
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3answers
1k views

chrony vs. systemd-timesyncd – What are the differences and use cases as NTP clients?

Somehow but not quite building upon the older question "ntpd vs. systemd-timesyncd - How to achieve reliable NTP syncing?", I'd like to ask about the differences between chrony and systemd-timesyncd ...
0
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1answer
53 views

Daylight saving in Debian 9

I would like to know how to enable Daylight saving support for Debian 9 with LXDE. My timezone is set to Europe/Rome. However my clock is one hour ahead and - considering Daylight saving - it shouldn'...
0
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1answer
38 views

Sync 1pps sync with system clock

We need to use 1pps (gpio source) for timestamp in application. I thought that ntp should be used with the linux pps for this purpose. But the system is standalone without any other servers connected....
4
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1answer
411 views

Failed to activate systemd-timesyncd.service

I've scanned all forums and questions and found no working answer to my problem. The Network Time Synchronization service doesn't work. The timedatectl service seems to work just fine without it ...
3
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1answer
27 views

Should I set the time in a container?

I have a few containers (systemd-nspawn based) and I am wondering whether I should set up the time (via systemd-timesyncd) or is it maintained by the host?
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2answers
50 views

How often (and when) does NTPD update the time?

I have an Oracle Linux 6 box (RHEL) and I have set up ntpd. I have run service ntpd start and chkconfig on. Now, if my date is incorrect and I reboot the box, it sets the time and date properly. ...
2
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1answer
68 views

wrong time at Ubuntu 16.04.1 LTS

I have VM with Ubuntu 16.04.1 LTS, and time is wrong. The difference is about 15 hours. I synchronize it via sudo ntpdate 1.ro.pool.ntp.orgevery day and then it becomes right, but next day I have this ...
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1answer
73 views

What do the ntp options “restrict default nopeer” do?

NTP version installed: ntp-4.2.6p5-5 I'm trying to understand the usage and meaning of the ntp restrict along with restrict default nopeer Quoting the NTP documentation: nopeer: Deny packets ...
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2answers
84 views

Can't install openntpd: “unable to find a suitable fs in /proc/mounts, is it mounted?” “pre-installation script returned error exit status 1”

I'm trying to install openntpd (sudo apt-get install openntpd) and I'm getting: Preparing to unpack .../openntpd_1%3a6.0p1-2_amd64.deb ... Warning: unable to find a suitable fs in /proc/mounts, is it ...
0
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1answer
41 views

How to get a working clock on Debian 9? Clock is wrong by a couple minutes

How to get a working clock in Debian 9 with KDE? My clock is almost 10 minutes slow on multiple of my machines running Debian 9 with KDE and (re)setting the timezone via tzselect didn't work. (I ...
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0answers
108 views

Running `ntpd -q -g` to set the time on Raspberry Pi never completes

On my Raspberry Pi which has been running for about 4 or 5 years now, I have a cron job running every hour that sets the time. I know form experience that my Pi has a tendency to drift its time quite ...
1
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1answer
100 views

ntpq does not print the list of the peers immediately

I'm on FreeBSD. I used from a cisco router as the server and my system as the client. I used ntp to sync the clock between server and client. It worked and the clock has synced but when I run ntpq -p, ...
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2answers
132 views

automatically run script on successful time sync - how?

i'm using rapberry Pi 3 with Stretch (debian-based) and timesyncd as NTP client. Pi is being switched of and on periodically and connects to internet through usb modem, then synchronizes time. syslog ...
0
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1answer
79 views

Offline time sync

Is there a reliable way to sync clock of a totally offline linux server, which is only occasionally connected to a client? I imagine passing a single "millis-since-epoch" number to the server may not ...
0
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2answers
421 views

Time drifting after NTP is configured

This is a XenServer 7.1 CU1 host. NTP should behave as in any other Linux distro. We have configured /etc/ntp.conf with following servers (have tried other servers with similar results and these ...
0
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0answers
50 views

How to address error messages when using openntpd's “constraints from” feature?

My openntp configuration is as so: servers pool.ntp.org sensor * constraints from "https://www.google.com" And I am seeing the following messages: constraint request to 2607:f8b0:4007:80b::2004 tls ...
1
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2answers
365 views

How to run ntpd as a server only, without adjusting local machine time, under LXC

I have a need to point devices to sync their clocks to my CentOS-7 server running inside LXC. On the server I'm trying to use ntpd from ntp package, but open to other products. This question is about ...
2
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2answers
182 views

Updating Linux system time programmatically

I have a system of 3 or 4 different Linux Ubuntu machines that I would like to be time synced. My plan is to use one of them (let's call it master) as the NTP server that serves time to the 3 other ...
2
votes
2answers
426 views

Delay further startup until time is synced

I'm running a Raspberry Pi Model 2B with Raspbian Stretch (Debian). I have a UI-application (chromium-browser, started via /home/pi/.config/lxsession/LXDE-pi/autostart) and a script started via cron, ...
0
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1answer
304 views

DHCP server does not include NTP server addresses in the DHCP ACK message

I am capturing DHCP packets with tcpdump. The client sends a DHCP request asking for the DHCP configuration which contains a request for NTP servers but in the DHCP ACK message sent by the router ...
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1answer
153 views

How to change broadcast periodicity of an NTP server

I'm configuring an NTP service on debian via /ect/ntp.conf. I made it as a broadcast so I set my clients as listeners. Is there a way to change the periodicity by which the NTP server sends its ...
0
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1answer
145 views

NTP Synchronization

I am configuring a NTP server to synchronize the time on the both systems, Linux and Windows. I'm using CentOS 7 and Windows Server 2012. In /etc/ntp.conf, I set the Windows Server IP address instead ...
1
vote
2answers
2k views

One time query to sync time with NTP server

I do not plan to configure NTP client to sync with the NTP servers for my Solaris servers. Is it possible that I connect to this NTP servers and sync the time on an ad-hoc basis?
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1answer
539 views

ntpstat works but not ntpq

I'm trying to configure NTP client on RHEL7.4 I'm running the "ntpstat" command and seeing that I have synchronized: [root@my-machine ~]# ntpstat synchronised to NTP server (ntp-server ip) at stratum ...
1
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1answer
59 views

how to verify difference time between linux machines not greater than 5 seconds

How may I verify that all machines, appolo01 - mars3, are less than 5 seconds offset from each other? ssh appolo01 date ; ssh appolo02 date ; ssh appolo03 date ; ssh mars1 date ; ssh mars2 date ; ssh ...
0
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1answer
182 views

Time gets 3 hours forward always on midnight

Every time I sync the time on a CentOS 7 (Scientific Linux 7) server virtualized on VMware ESXi, I arrive the next day to find that the time gets 3 hours forward. I did a cronjob to write the time ...
1
vote
1answer
545 views

Looking for a simple NTP setup for CentOS 7

I need to set up an NTP server for testing purposes on a non-internet-connected network, but I am having issues finding a clear-cut example of what to do to get this to work. This NTP server will be ...
0
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0answers
655 views

chrony not updating the server time properly in Centos 7

I am using chrony for NTP time synchronization for my Centos 7 server. some time I notice some servers time is not correct, I have to use ntpdate command to correct the time. I have below ...
1
vote
1answer
240 views

Unable to get ntp to synchronize time

I would like to synchronize the time for a machine. This computer is on a university network which is somehow protected. I don't have any change of time. Here is my configuration (default on debian). ...
0
votes
1answer
519 views

CentOS 7 timedatectl does not work properly with chronyd

In order to have timedatectl NTP enabled and synchronized to be yes, I had to disable chronyd, stop ntpd, perfrom ntpdate, then start ntpd. After that I can get NTP enabled and synchronized in ...
1
vote
2answers
824 views

Time drift and wrong timezone within NTP configuration

We have 2 VLANs, each VLAN has a server that provides DHCP, DNS and NTP to its corresponding VLAN. These 3 servers take time from a local NTP server. Here is the configuration of NTP client and ...
2
votes
2answers
1k views

NTP not updating with local timeserver

I have a raspberry pi hooked up to a local network where there is not internet acces. I have configured a computer to act as a timesever (windows timeservice). The timeserver has the ip 192.168.6.1 ...
0
votes
1answer
1k views

How can I use my local time as the only reference of `ntpd`?

I want to let my Linux device synchronize its local time with the local time of another Linux server without any other references. I don't care about the actual time. I want my fake time. Therefore I ...
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2answers
247 views

Can I start ntp.service after boot?

I've had issues with ntp drastically increasing the startup time, and I am not the only one, see for example here. Since it is responsible for adjusting my system time, I see no important reason for ...
0
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1answer
228 views

System time is changed automatically for some unknown reason on Linux machine

I asked the same question on SOF but be told this is the more appropriate place. There's a very weird problem about system time on one of my Linux machines, the system time is kept being changed to 40 ...
4
votes
3answers
3k views

NTP time sync takes a long time

I use a Raspberry Pi 3 and need to update the time via ntp after reboot the system. It should be updated via wifi with dhcp. Generally it works, but the synchronisation needs approx. a half an hour ...
0
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2answers
2k views

ntpd Configured for IPv6, Not Binding IPv6 Port

I have the following /etc/ntp.conf on CentOS 7.4: # /etc/ntp.conf: Ansible managed # drift file driftfile /var/lib/ntp/drift # restrictions restrict default nomodify notrap nopeer noquery restrict ...
0
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1answer
436 views

NTP Server - sync from local system clock

I need to create device (currently Raspberry Pi 3 based) which states as NTP Server, it has no connection to Internet and NTP should read actual time from local system clock (this clock is set from ...
1
vote
1answer
235 views

NTPD fails to update time correctly

After getting my Arch laptop to connect to my phone's hotspot, I was having trouble connecting to any websites that were't cached (for the most part, anything but Google). I looked a little, and ...
0
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1answer
236 views

Interpretation of PTP4L and PHC2SYS syslog records

I'm using the ptp4l and phc4sys services to syncronize the clocks of my Centos 7.4 servers to a central PTP source. The services regularly write syslog records like the one below. I haven't found any ...