Understanding chronyc command fields

I am using chronyc to check the status of synchronization. I am trying to interpret the meaning of the fields associated with several chronic commands such as tracking, sources, sourcestats. I need help confirming some of the understanding that I have developed from the website Ubuntu Manpage: chronyc - command-line interface for chrony daemon

chornyc tracking :
Example data from my computer

Reference ID    : AC693CA7 (ntp-pool.time.4v1.in)
Stratum         : 7
Ref time (UTC)  : Sun Mar 24 16:19:48 2024
System time     : 0.000063957 seconds slow of NTP time
Last offset     : +0.000293266 seconds
RMS offset      : 0.000904153 seconds
Frequency       : 7.241 ppm slow
Residual freq   : +0.015 ppm
Skew            : 0.370 ppm
Root delay      : 0.062447630 seconds
Root dispersion : 0.002806796 seconds
Update interval : 258.5 seconds
Leap status     : Normal

I am confused with system time and last offset fields.
The explanation provided at the attached link above states that system time represents the time difference between the current system time and true time as estimated by Chronyd, whereas the last offset indicates the estimated local offset on the last clock update.


  1. What does local offset mean? does it refer to the time difference between the current system time and true NTP time?
  2. A positive value of the last offset means that the local time(I assume that refers to system time) is ahead of time sources. In the above terminal output of chronic tracking, system time indicates that the system is behind(slow of) NTP time, but the last offset is positive. What does this situation mean?
    What is the difference in system time and offset?
    I see that when I do chronyc sourcestats, I get one of the fields as offset. What is the difference in the offset specified here and the system time specified under chronyc tracking, I don’t see that they have the same values.
  3. What are the criteria for chronyd to change the leap status from unsynchronized to normal?
    Is it just based on the difference between the current system time and NTP’s estimated true time?

Thank you for the help!

Last offset is the change in the current estimate of true time. System time shows how close is the system clock to that estimate of true time. Even if the estimate steps ahead, it can still be behind the system clock. The signs don’t have to be the same.

sourcestats show the estimated offset for each individual source. tracking shows the combined and weighted result.

The leap status is changed when there is any update to a synchronized source.

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