[time-nuts] Re: Clock display on Linux systems?

[Hal Murray]

> I have another Raspberry Pi that uses ntpq to query all of my
> clocks, along with two commercial NTP servers on my network,
> plus two external servers, and compares them.

ntpq doesn't really compare them.  It just reports what the other ntpd thinks 
is going on.  You might be able to get (some of?) what I think you want by 
parsing the ntpq peers output.

When I want to compare clocks, I setup a good ntpd system with logging.  Then 
I add extra server commands for the systems I'm interested in if they aren't 
already there.  If you add "noselect" to the server line, ntpd goes through 
all the normal data collection and logging but doesn't use the data from that 
server to control its local clock.

loopstats will tell you how good the system thinks its clock is.

rawstats will give you the 4 timestamsp from each request-response exchange.
peerstats is the filtered and digested data from rawstats.
  This is what ntpq -p shows.
loopstats is the filtered/digested data from peerstats.

All those files are ready to feed to gnuplot.  The normal logging is one file 
per day.  If you want to see more than one day at a time, I suggest a 
preprocessing script to link filenames you use in gnuplot to the log files.  
Things like:
 loop-2 -> loopstats.20211204
 loop-1 -> loopstats.20211205
 loop -> loopstats.20211206

If you are using ntpsec, the ntpviz stuff may do what you want and/or may be a 
good place to start.  It's a set of scripts that uses gnuplot to turn log 
files into bunch of graphs (gif/png?) that you can feed to a web page.

I'll say more if anybody wants help going down this rathole.


-- 
These are my opinions.  I hate spam.