[AusNOG] A lot of AU NTP Servers appear to be misconfigured, and it's mildly annoying me.

[Rob Thomas]

I was rebuilding my local network over the weekend, and as part of
that I had to relocate and reconfigure my Stratum 1 NTP server. As I
was fine turning it, I discovered a significant number of Au NTP
servers are misconfigured, and I thought I'd post a few quick tips
here, for anyone providing a timing source, and using a GPS signal as
Stratum 0.

1. If you're not using PPS triggers, PLEASE DON'T MARK YOURSELF AS A
STRATUM 1 SERVER! Put this in your /etc/ntpd.conf:

server 127.127.28.0 minpoll 4 maxpoll 4 stratum 2
fudge 127.127.28.0 time1 0.135 refid GPS

(Obviously adjusting your time1 amount to match whatever the delay of
your GPS chip is)

2. If you ARE using PPS triggers, make sure that is flagged 'prefer'.
This means that when you run `ntpq -n -p` you will have a * by 28.2
.PPS.

3. You MUST be using the SHM driver (127.127._28_.x), not the NMEA
driver (127.127._22_.x) for anything even slightly accurate.

4. If you're doing this on a Pi, please feel free to message me
offlist and I will happily spend some time with you setting up a
complete working config to make your own Stratum 1 server.   To get
your started, here's what I'm uising as my /etc/ntp.conf on my stratum
1 server:  https://pastebin.com/7c6P0aYv

I'll also be doing some BoF's on Timekeeping at Linux.conf.au next
year, if anyone wants to nerd away about excessively accurate time
keeping for ensuring your logs are correct, and displayed in the
correct order.

--Rob