Hello everyone!

I've been tinkering with LinuxPTP a bit, but there's something which I
don't fully understand, namely re-synchronization.

I've set up my slave by starting 'ptp4l', and I've started 'phc2sys' to
synchronize the slave's clock (I presume that it's CLOCK_REALTIME which is
being synchronized) to the master.

These are the commands which I've been running:

   - ptp4l -m -i enp4s0 -p /dev/ptp0 -s -H
   - phc2sys -s enp4s0 -w

Works fine the first time around, but if I try to change the time on the
master using the following:

   - phc_ctl /dev/ptp0 set 1337.0

This is not immediately reflected on the master.
The change in the master's time shows up as an increased rms offset in the
output from 'ptp4l', or in the 'offsetFromMaster' printed when executing
the following on the slave:

   - pmc -u -b 0 'GET CURRENT_DATA_SET'

I've also written a small program which executes 'clock_gettime' on all my
clocks at a 60Hz rate and prints the tv_sec and tv_nsec variables, and this
program has the same behavior - i.e. it does not show any
re-synchronization after executing 'phc_ctl /dev/ptp0 set 1337.0' on the
master.

Is my understanding incorrect? Is it not possible to achieve automatic
re-synchronization if the master's clock jumps in time?
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