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Questions tagged [chrony]

a pair of programs which are used to maintain the accuracy of the system clock on a computer.

chrony is a pair of programs which are used to maintain the accuracy of the system clock on a computer. The two programs are called chronyd and chronyc.

chronyd is a daemon which runs in background on the system. It obtains measurements via the network of the system clock’s offset relative to time servers on other systems and adjusts the system time accordingly. For isolated systems, the user can periodically enter the correct time by hand (using chronyc). In either case, chronyd determines the rate at which the computer gains or loses time, and compensates for this. chronyd implements the NTP protocol and can act as either a client or a server.

chronyc provides a user interface to chronyd for monitoring its performance and configuring various settings. It can do so while running on the same computer as the chronyd instance it is controlling or a different computer.

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Synchronize clock with NTP while online, and with RTC while offline?

Is there a existing mechanism that synchronizes a linux system with NTP while online, and with a predictably drifting RTC while offline? We operate remote "collectors": embedded Linux systems that collect and timestamp sensor data. We need their…
Nils Toedtmann
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Force chrony time check

Context: Centos 7.0 chronyc (chrony) version 3.1 (+READLINE +IPV6 +DEBUG) Issue I want to find a way to force chronyd to change the hardware clock instantly without waiting. The program chronyd is currently running on my machine : [root@localhost…
Orelsanpls
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Verify internal NTP server is sending the correct time?

I have two NTP stratum 3 servers running and wanted to create a simple check that I could tell if either of the servers time drifted and alert that it's not synced properly with the public stratum 2 servers. My first thought was to pull time from…
krizzo
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Chrony time synchronization on huge time diff

hello currently i have a localy ntp server (chrony) and a ntp client (chrony), all are working but when i try to change ntp server time to say minus 6 years from current time. ntp client cannot sync with it, it will just say on syslog: Jan 9…
lemoncodes
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Chrony doesn't appear to be syncing with the servers I've specified

I have set Chrony to sync with 4 NTP servers (config file below). When I run chronyc tracking and chronyc sources, it looks like the servers my machine is connecting to for NTP are not correct. I'd expect to see the list of servers I specify in the…
Chris Williams
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"system clock synchronized: no", flip it to yes

# timedatectl outputs Local time: Tue 2020-10-06 13:35:31 PDT Universal time: Tue 2020-10-06 20:35:31 UTC RTC time: Tue 2020-10-06 20:35:30 Time zone: America/Los_Angeles (PDT, -0700) System…
Katerl3s
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ntpd synchronizes but chronyd fails

I am setting up a time server with chronyd but it fails to sync. # chronyc sources 210 Number of sources = 5 MS Name/IP address Stratum Poll Reach LastRx Last…
Joe
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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 from the terminal. Is there any alternative…
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The "least bad" settings for Chrony as the NTP server on a virtual machine

I'm tasked with rebuilding a LAN server that's serving as the NTP server for hundreds of client machines. Unfortunately, it's on a virtual machine, and as demonstrated by questions like What are the limits of running NTP servers in virtual machines?…
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gpsd.socket for chrony does not work

I tried to get more accurate time from gps data using ublox module and centos but it seems gpsd.sock does not work properly to get the data to chrony. am I missing somthing ? [root@info /]# cat /etc/chrony.conf # Use public servers from the…
Bell-guest
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chrony does not log anything on my ec2 instance

i am trying to gather statistics from the chrony daemon on my EC 2 (Ubuntu 18.04.2 LTS) instance. i have followed aws's guide on how to set it up and it runs as expected. i need to compare the time sync difference between aws and another service…
Eitan Kats
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Decentralized NTP in network with only sporadic internet connectivity?

I have a (most of the time) isolated network consisting of several computers. computer 0 -- external NTP server / switch -- computer 1 -- external NTP server \ computer n -- external NTP server Only a small…
Bloops
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Chrony reporting system time slower than NTP and growing

I have chrony running on several of my instances. Unfortuantely, on one of them, it keeps reporting that the system time is slower than NTP time. This number of seconds keeps growing at a rate of about 10 seconds per minute. Here is one…
checklist
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Chrony synchronization

After I configured chrony service on my CentOS 7.3 to point to the active directory, it shows below > chronyc sources 210 Number of sources = 1 MS Name/IP address Stratum Poll Reach LastRx Last…
Lan
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Real-time clock is wrong (from hours to years), one-time non-monotonic change at boot needed. Can Chrony solve this?

I can't guarantee a sane real-time clock on some machines (the time might be wrong by hours, months or even years). Since I also have intermittent networking, I set up Chrony in the hopes it could fix the issue. But it seems that Chrony wants to…
darque
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