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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RTC / systemd time drift
I do see the following behaviour on a SUSE SLE 15 VM
(VMWare ESXi, location setting is Europe / Germany)
and getting confused the more I think about it.
I have shortened the journal-log output to the ...
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Why is the root distance to my router 2 minutes when pinging it takes 300μs?
I have an Arch Linux system and I am using systemd-timesyncd.service to poll my router for time sync.
My router is a MikroTik one with NTP server set up. The router and Arch are connected directly via ...
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Comparing Solaris NTP and MacOS SNTP results? Is this accurate time?
What are expected values for offset and jitter from NTP?
I have Solaris 11.4 in a VM with NTP configured and am comparing Solaris time stats to my Mac. I notice that MacOS sntp -sS time.apple.com ...
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Units of tick in struct timex
Linux header files and man pages for adjtimex(2) and ntp_adjtime(2) describe struct timex, containing a tick field that is described as the number of microseconds for each system clock tick. However, ...
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How to prove that NTP time sync is checking regularly
How does one prove that systemd-timesyncd is regularly polling the NTP servers to ensure that the system's clock remains "synchronized"?
I understand that I can check the yes/no sync'd ...
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GNU `make`, modification times, leap seconds and NTP
GNU make relies on timestamps to see if a dependency was changed after some file was built. If you make a change during the leap second or an NTP adjustment, is it possible that make will believe the ...
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NTP client cannot sync date from a specific Server
I want to create a NTP server, and my clients could sync date from this Server.
So I add restrict policy in my server, and then restart the NTP service to my it works as a NTP server. Then I add this ...
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Why is the NTP time off relative to the NIST standard?
The NIST official U.S. time website shows the current UTC and also my device's time and calculates an offset, see attached screenshot:
To my surprise the time difference, which varies during the day, ...
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Why the ntpq -c subcmds outputs nothing received, but still can properly sync its time
Environment: RHEL 6.4 with ntp-4.2.6p5-15.el6_10.x86_64
Question: the following ntp client can sync its time to the remote ntp server, but why it cannot run the ntpq -c subcmds with the remote ntp ...
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NTP client on Compact-RIO RT linux system
I'm trying to synchronize the time of my National Instruments real time system (model Crio 9053) running a Linux OS. I tried a ntpdate 192.168.10.3 command and this working well, but after that the ...
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Date is incorrect in wifi : system clock synchronization is not active
I have compiled a read-only rootfs image with yocto for my raspberrypi4. I have noticed that my date is incorrect uniquely in wifi.
Indeed when I type the command timedatectl status I have the ...
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chrony takes many minutes to read refclocks after boot
I'm looking to provide precise time to a Raspberry Pi 4 without internet via a UBLOX GNSS module that sends NMEA sentences to /dev/serial0 and a pulse-per-second (PPS) signal to /dev/pps0.
All this ...
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How to force update NTP date/time on a router?
The log of an Asus router with Padavan firmware (might be similar to OpenWrt) showed:
Dec 4 16:06:20 NTP Client: Synchronizing time to 0.nl.pool.ntp.org.
Oct 24 18:18:18 NTP Client: System time ...
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Understanding NTP stratum
In Linux (RHEL 7+) how can I get the stratum value of an NTP server I had specified to use in /etc/chrony.conf ?
For the List of Top Public Time Servers if that is correct, some are identified as ...
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timedatectl shows wrong local time
this the output of my timedatectl command on a proxmox VM running on a server in New Zealand with static IP:
$ timedatectl
Local time: Wed 2023-11-01 16:01:30 UTC
Universal ...
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Chronyd clients query
it's possibile see log of sync query from client?
There are tracking.log statistics.log measurements.log but in this log there are not clients query
I try from my client to query with command
ntpdate ...
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System time synchronization between two hosts using linuxPTP
I would like to setup a high-precision system time synchronization between two machines using linuxptp.
On the first host:
the system time is periodically synchronized using NTP using an interface ...
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How to set NTP synchronized to yes in Linux without NTP sync?
How to set NTPSynchronized to yes in Linux without actual NTP synchronization?
I just want to cheat some program.
]$ timedatectl show -p NTPSynchronized
NTPSynchronized=yes
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Ntpd client strange behavior
Jetson NX with latest Jetpack, NTP Ver. 4.2.8p10
I have some pools in /etc/ntp.conf (0.europe.pool.ntp.org)
When I try ntdate -q 0.europe.pool.ntp.org all is ok
But there is nothing except one ...
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How can I determine the current reliability [correctness] of the system time?
I'm working on a project which will acquire a lot of timestamped data at fairly high resolution (50 samples per second) over a very long period of time (years).
The solution includes various failover ...
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Why is my ntp not updating?
I have a Debain console-only system.
I just realized it's not updating it's clock:
$ date
Mon 10 Aug 20:33:23 BST 2020
$ ntpdate
10 Aug 20:27:45 ntpdate[8029]: no servers can be used, exiting
$ ...
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Where is timedatectl information stored?
I am working on an embedded system without RTC battery. The time is synchronized via NTP when internet connection is available (which does not always happen). When the device is shut down, the time is ...
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Using RTC PPS for syncing computer by NTP
I've seen a decent amount of documentation for how one would use a GPS and its PPS signal along with an NTP package (like ntpd or chrony) to synchronize the computer's clock.
I have a need similar to ...
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Relocation error when running NTPv4 (cross-compile) on ARM device
The error message I am getting when running ntp-keygen (or ntpd) on my ARM device is:
./ntp-keygen: relocation error: ./ntp-keygen: symbol DSA_generate_parameters_ex, version OPENSSL_1_1_0 not defined ...
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Missing features compiling NTP vs installing already built
I have found that if I compile NTP myself, the package ntp-keygen is missing Autokey authentication features.
The help screen of my compiled ntp is as follows:
Whereas if I just apt-get install ntp, ...