How to check Chronyc clock and sync our system clock ?
Today in this post, we will see how to check chrony status on our system and sync our clock in case its not synced.
Lets look step by step how to do this.
1. Check chronyd service and its log visible in service status.
[root@ngelinux001 ~]# service chronyd status
Redirecting to /bin/systemctl status chronyd.service
● chronyd.service - NTP client/server
Loaded: loaded (/usr/lib/systemd/system/chronyd.service; enabled; vendor preset: enabled)
Active: active (running) since Wed 2022-08-24 08:39:51 EDT; 2 days ago
Docs: man:chronyd(8)
man:chrony.conf(5)
Process: 1454347 ExecStartPost=/usr/libexec/chrony-helper update-daemon (code=exited, status=0/SUCCESS)
Process: 1454342 ExecStart=/usr/sbin/chronyd $OPTIONS (code=exited, status=0/SUCCESS)
Main PID: 1454345 (chronyd)
Tasks: 1 (limit: 101096)
Memory: 360.0K
CGroup: /system.slice/chronyd.service
└─1454345 /usr/sbin/chronyd
Aug 24 08:39:51 ngelinux001 systemd[1]: Starting NTP client/server...
Aug 24 08:39:51 ngelinux001 chronyd[1454345]: chronyd version 3.5 starting (+CMDMON +NTP +REFCLOCK +RTC +PRIVDROP +SCFILTER +>
Aug 24 08:39:51 ngelinux001 chronyd[1454345]: Frequency -36.476 +/- 0.900 ppm read from /var/lib/chrony/drift
Aug 24 08:39:51 ngelinux001 chronyd[1454345]: Using right/UTC timezone to obtain leap second data
Aug 24 08:39:51 ngelinux001 systemd[1]: Started NTP client/server.
Aug 24 08:42:01 ngelinux001 chronyd[1454345]: Selected source 139.99.240.5
Aug 24 08:42:01 ngelinux001 chronyd[1454345]: System clock TAI offset set to 37 seconds
Aug 24 08:42:01 ngelinux001 chronyd[1454345]: System clock wrong by -2.848067 seconds, adjustment started
Aug 24 08:41:58 ngelinux001 chronyd[1454345]: System clock was stepped by -2.848067 seconds
2. Check the server from which the clock gets synced.
[root@ngelinux001 ~]# tail /etc/chrony.conf # Get TAI-UTC offset and leap seconds from the system tz database. leapsectz right/UTC # Specify directory for log files. logdir /var/log/chrony # Select which information is logged. #log measurements statistics tracking server ntp-ngeindia.ngelinux.com [root@ngelinux001 ~]#
3. Sync the clock from server.
[root@ngelinux001 ~]# chronyd -q 'server ntp-ngeindia.ngelinux.com iburst' 2022-08-24T11:35:13Z chronyd version 3.5 starting (+CMDMON +NTP +REFCLOCK +RTC +PRIVDROP +SCFILTER +SIGND +ASYNCDNS +SECHASH +IPV6 +DEBUG) 2022-08-24T11:35:13Z Fatal error : Another chronyd may already be running (pid=1071), check /var/run/chrony/chronyd.pid [root@ngelinux001 ~]# ### Check out the PID [root@ngelinux001 ~]# cat /var/run/chrony/chronyd.pid 1071 ### Check the process ID [root@ngelinux001 ~]# ps -ef | grep -i 1071 chrony 1071 1 0 Aug18 ? 00:00:00 /usr/sbin/chronyd root 1440367 1436528 0 07:36 pts/3 00:00:00 grep --color=auto -i 1071 [root@ngelinux001 ~]#
4. Check out the clock sync tracking.
[root@ngelinux001 ~]# chronyc tracking Reference ID : 8B63F005 (ntp_server.ngelinux.com) Stratum : 9 Ref time (UTC) : Wed Aug 24 11:26:00 2022 System time : 0.000152016 seconds slow of NTP time Last offset : -0.000289631 seconds RMS offset : 0.000226364 seconds Frequency : 36.101 ppm slow Residual freq : -0.005 ppm Skew : 0.089 ppm Root delay : 0.075418741 seconds Root dispersion : 0.004744601 seconds Update interval : 1029.2 seconds Leap status : Normal [root@ngelinux001 ~]#
5. Verify the sources/server.
[root@ngelinux001 ~]# chronyc sources
210 Number of sources = 1
MS Name/IP address Stratum Poll Reach LastRx Last sample
===============================================================================
^* ntp_server.ngelinux.com 8 10 377 731 -1308us[-1597us] +/- 42ms
[root@ngelinux001 ~]#
### Verify the source stats
[root@ngelinux001 ~]# chronyc sourcestats -v
210 Number of sources = 1
.- Number of sample points in measurement set.
/ .- Number of residual runs with same sign.
| / .- Length of measurement set (time).
| | / .- Est. clock freq error (ppm).
| | | / .- Est. error in freq.
| | | | / .- Est. offset.
| | | | | | On the -.
| | | | | | samples. \
| | | | | | |
Name/IP Address NP NR Span Frequency Freq Skew Offset Std Dev
==============================================================================
ntp_server.ngelinux.com 21 13 362m -0.005 0.080 -4150ns 630us
[root@ngelinux001 ~]#
Hope this is useful, and now you can identify if the clock is synced or not and sync it to the server is there is offset.