[ntp:questions] Thunderbolt at NTP ref clock.

David Lord snews at lordynet.org
Tue Jul 30 16:24:17 UTC 2013

Dave Baxter wrote:
> Hi again.
> In reference to my other thread.
> "THunderbolt monitor/control on Win7 ?"
> Well, as that device seems happy in it's potential new home.
> I've been poking about the interweb looking for info as to getting the 
> TB used as a reference clock for NTP.
> I found this page:-
> http://www.eecis.udel.edu/~mills/ntp/html/drivers/driver29.html
> That on the face of it, seems to tell me what I need.
> So, poking arround (no changes yet) my ntp.conf file, I "think" I need 
> this:-
> # Trimble Thunderbolt on /dev/gps1 (first serial port)
> server    mode 2  minpoll 4 maxpoll 4   prefer
> fudge    time1 0.020
> fudge    flag2 1  refid GPS
> server 0.uk.pool.ntp.org iburst minpoll 5 maxpoll 12
> server 1.uk.pool.ntp.org iburst minpoll 5 maxpoll 12
> server 2.uk.pool.ntp.org iburst minpoll 5 maxpoll 12
> Would this be suitable for general purpose local time sourcing?  With 
> fallback to the pool if the TB burps, dies or is otherwise compromised.

I'd add a few more public servers, I've been using five.

> Could all the fudge factors go on one line?

Shouldn't be a problem.

fudge    time1 0.020  flag2 1  refid GPS

> (Sorry to ask silly questions, but I don't know, so have to ask.)
> If so, in what (if any) order?
> The server currently run's FreeBSD 8.0  Uptime over 772 days now, 
> without a hitch! Nice...   (I do plan to configure another box, running 
> 9.x at some point to replace this one.)  
> ntpq -crv reports (among other things)...
> version="ntpd 4.2.4p5-a (1)"

I'm using 4.2.6p5 but that is fairly old (Dec 2011 maybe). One
of the 4.2.7pnnn may be a better choice although I tried both
4.2.4p354 and p359 on NetBSD and had problems using the stom



> Recomendations, brickbats etc?
> Cheers.
> Dave B.

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