Questions tagged [clock-synchronization]
58 questions
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Prevent VM clock running faster than it should
I have a unRAID 6.6.5 server with perfectly correct time and multiple Linux VMs which used to be perfectly synced too. I rebooted one of my VM and suddenly the clock goes twice as fast as the hwclock. I can easily see that by doing these 2 loops in…
dan
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Preventing system clock from auto-updating in Windows Server 2012
I'm working on a project right now where as part of testing I have to move the system clock to far-off future dates. There are two servers involved in the project: an app server and a database server. I've stopped the Windows Time service on both…
John Clifford
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NTP synchronized clock alongside the system clock
Does NTP daemon(ntpd) provide some sort of virtual clock that it disciplines and serves, but not touch the system clock?
Goal:
On a realtime Linux OS, have a NTP synchronized clock alongside of the system clock, so that ntp time changes won't cause…
Vikyboss
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RTC/UTC was innacurate on MySQL (MariaDB) server. I fixed it - was that bad?
I'm pinch hitting as an admittedly green server admin. I installed a bunch of security patches on a MariaDB server that had an incorrectly configured repo (not by me) and wasn't getting patches for a while. After install and reboot, I noticed all…
bendodge
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Why is clock synchronization on servers difficult?
See: Clock synchronization quality on Windows Azure?
This is not meant as a rant, it is just curiosity.
Is a computer really drifting more than a second in a single day? I can barely imagine that.
Why not a sync every day to a time server. This…
Dirk Boer
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5 answers
How do I synchronize clocks between Linux and Windows?
I am running some benchmarks between a Windows client and Linux server. In order to measure the latency correctly I need to synchronize the clocks between the two machines before starting the test - ideally down to the nearest millisecond - what's…
Supertux
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Cent OS 6 clock 3 minutes 35 seconds in the future
I run Cent os 6 64 bit on linode.
server (incorrect):
date
Thu Aug 29 11:41:00 BST 2013
client (correct):
date
Thu Aug 29 11:37:25 BST 2013
As you can see the server clock is in the future.
so far I have ensured the server is running…
Code Review Doctor
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Update clock on virtualbox virtual machine with cent os from host
I have a virtual machine, with cent os installed, and everytime I sleep the host computer, the clock of the VM goes out of sync. I would like it to pick up the current time from virtualbox - which I would expect it to do naturally.
How can I force…
Billy Moon
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How "real" is the POSIX clock in a virtual machine?
Introduction:
Time is OS like Linux is typically derived from a clock chip (RTC), or maintained by software using either periodic interrupts or some hardware registers (e.g. CPU's TSC cycle counter) for implementation.
Obviously in a virtual machine…
U. Windl
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Incorrect PTP timestamps
I have trouble syncing to Linux systems using PTP.
Setup:
Two PCBs with a BegleCore module and a DP83640 PHY are connected with each other over Ethernet. One board should act as the PTP master, the other as the slave.
Debian 10, Kernel:…
11011100
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How to Set Up Time Synchronization with NTP on Ubuntu 20.04.1 LTS
After updating the base system with the latest available packages:
apt-get update -y
and
root@localhost:~# timedatectl
Local time: Wed 2021-01-06 08:03:11 UTC
Universal time: Wed 2021-01-06 08:03:11 UTC
…
0
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1 answer
Problems with chronyd Centos 7 all updates applied
I have an email server running on top of CentOS7. This is a new server and has been in production for 2 days. It seems that chronyd is losing it's connection to the ntp servers that it contacts at pool.ntp.org. I have set up 0.pool through 3.pool in…
tgz
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How to have WSL think it is in the past?
I am developing PHP/Apache/MySQL based code on my Windows 10 laptop via Windows Subsytem For Linux.
I am working on some code that is time related. It has a mix of PHP date commands, and MySQL "NOW()" calls. I need to be able to work on this at any…
Hippyjim
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/sbin/hwclock --utc --systohc not working on AWS EC2 under Ubuntu
I'm in the process of moving some servers to AWS. One problem I'm encountering is that my script to synchronize the time using ntpdate and then write that time to the hwclock is failing. When the server reboots, I'd like the time to be close to…
Stephen Ostermiller
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How to read VMware interrupt backlog?
The VMware document titled "Timekeeping in VMware Virtual Machines" have the following referente to the issues with the time drift:
If the virtual machine is running too slowly, perhaps as a result of competition for CPU time from other virtual
…
rfmoz
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