CentOS 7 – How to Sync Time Automatically and Manually with Chrony

centoscentos7linuxntptime-synchronization

Seems there's no ntpd in centos7, how can I sync time in centos7?

I found out that chrony should be used in centos7, what is manual way to update time using chrony?

I assume chronyd is something equivalent to ntpd? and what's the command equivalent to ntpdate -s time.nist.gov?

Best Answer

Unless you've changed chrony's configuration, you don't need to do anything but start the service.

systemctl enable --now chronyd.service

The default configuration automatically steps the clock at startup (using the makestep directive) if it is more than one second different than the default NTP servers.


If you explicitly removed makestep from the configuration, you can step the clock by using the command

chronyc makestep

You should NOT do this if you used the non-default rtcfile option though, as it will cause the RTC drift to be recorded incorrectly.


For further details see the RHEL 7 chrony documentation.