[chrony-users] ntpd refclock drivers with chrony

[Miroslav Lichvar <mlichvar@xxxxxxxxxx>]

There is a new wrapper for refclock drivers implemented in ntpd, which
should allow chronyd to use any refclock supported by ntpd. It's
primarily intended for users with refclocks which are not supported by
gpsd, but if anyone would like to try it with a GPS, it should work
too.

https://github.com/mlichvar/ntp-refclock

Comments, bug reports and pull requests are welcome. It should work
with the latest ntp release (ntp-4.2.8p10). A man page will be added
later.

The command line syntax is similar to the server and fudge directives
of ntpd. Here is an example using the NMEA driver at 115200 bps with
PPS enabled:

# ntp-refclock -s /var/run/chrony-GPS.sock -d -c log \
	127.127.20.0 mode 80 time2 +0.5 flag1 1

With the SHM, ATOM and GPSD drivers in ntpd, it seems we now have 13
options how a GPS NMEA+PPS device can be used with chronyd. :)
Currently, I'd not recommend using the ATOM driver as it produces
samples even when the system clock is not synchronized. I don't have
much experience with the GPSD driver.

1) gpsd SOCK
2) gpsd SHM 0 + /dev/pps0
3) gpsd SHM 0 + ntp-refclock 127.127.22.0 (ATOM)
4) gpsd SHM 1
5) ntp-refclock 127.127.20.0 (NMEA) + /dev/pps0
6) ntp-refclock 127.127.20.0 (NMEA) + ntp-refclock 127.127.22.0 (ATOM)
7) ntp-refclock 127.127.20.0 flag1 1 (NMEA with PPS)
8) gpsd + ntp-refclock 127.127.28.0 (SHM) + /dev/pps0
9) gpsd + ntp-refclock 127.127.28.0 (SHM) + ntp-refclock 127.127.22.0 (ATOM)
10) gpsd + ntp-refclock 127.127.28.1 (SHM)
11) gpsd + ntp-refclock 127.127.46.0 (GPSD) + /dev/pps0
12) gpsd + ntp-refclock 127.127.46.0 (GPSD) + ntp-refclock 127.127.22.0 (ATOM) 
13) gpsd + ntp-refclock 127.127.46.0 mode 1 (GPSD with PPS) 

-- 
Miroslav Lichvar

-- 
To unsubscribe email chrony-users-request@xxxxxxxxxxxxxxxxxxxx 
with "unsubscribe" in the subject.
For help email chrony-users-request@xxxxxxxxxxxxxxxxxxxx 
with "help" in the subject.
Trouble?  Email listmaster@xxxxxxxxxxxxxxxxxxxx.