[ntp:questions] Local (own site) NTP servers.

G8KBV g8kbvdave at googlemail.com
Thu Jul 23 13:30:25 UTC 2009


Wonder if this will get posed, or returned to me..

Hi...

Been lurking for a while.

Also, been messing about trying to get a local (to me) GPS
Disciplined NTP server working, based on David Taylor's work
with FreeBSD, I think I have one of those configured OK, but
I've got other issues with FreeBSD on that machine that sort
of prevent me using it for unattended "appliance" use.  It
keeps generating system emails for the Root user, and I can't
find out why!  Other than its something about recovered editor
files?

So...  I'm about to try a couple of Windows "solutions"
(opportunities)  One the "Tardis" program, that would appear
to be able to take PPS based GPS signals, and act as a server.
Have to say, if it works, that would be a good solution for
some other interested parties (near zero config!)   The author
of that app seems to think it should work (they would I
guess?)   Plus, I know my way around most of Windoze, unlike
my knowledge of Linuz/BSD or whatever, that just slows me down
to the point of frustration.  No one in the (local to me) LUG
is interested in any of this sort of thing sadly.

(& just why is it that about all 'nix documentation and help
files, are written almost exclusively to obfuscate the needed
information?)

Also the Meinberg NTP software (not looked at in detail yet)
Both of them (independently while I play with them) will each
live on a dedicated PC for now, but ultimately one or the
other would need to co-exist on the same PC with the
monitoring program (Faros) that needs the time stamps.
Pointing it's NTP client routines at LocalHost?  Low single
figure mS jitter is OK, sub uS accuracy is just not needed.

However, while involved in something else, this came to my
attention....

http://bifferos.bizhat.com/

Now, I realise the clock speed is not that quick by modern
standards, but could that have enough "grunt" to work as a
GPSDNTP server for a small low traffic LAN?..

OK, I've managed (I think, as earlier) to get an older version
of FreeBSD to run for this sort of thing (on a 500MHz P3
machine)  But, just how cut down can it go, with just enough
left to boot and do the NTP task, or is the Kernel BifferOS
uses capable of half decent NPT serving tasks as it is?  It
appears to use a version of the same code others are using in
the WRTG routers for other purposes.

Or, has anyone done similar with "re-purposed" Router hardware
for example (Linksys, Sweex, etc)   I am aware of someone
selling (too rich for me!) a GPSDNTP server based on a "Slug"
(eBay 180384450442) using a USB connected GPS.

My ultimate goal?

To get Faros (HF Beacon monitoring program, runs on Windows,
only.)  A GPSDNTP source, HF Receiver control app (my own
code) and the resulting web based status page (or website
updater) all living on the same PC.  I may have a 1GHz P3
available, if I can get replacement RAM for it.  With Win2k
already resident.  And a couple of Garmin GPS16LVS devices,
verified working with 1PPS output.

Now, if Alex would integrate GPS timekeeping within Faros, all
this would not be needed, but he has his own reasons it seems
for not doing so.  As a result, it needs a 24/7 'net
connection, or access to some other NTP time source.   My
ISP's servers are somewhat less than reliable at times,
likewise access to others due to unpredictable and huge WAN
network latencies from time to time.

I also can't help wondering if any of the modern single chip
microcontrollers, some of which have available IP stacks,
could do the GPSDNTP thing in raw machine (or compiled) code.
But try as I might, I can find no reference to anyone trying
such a thing.

I am of course trying to keep the electric bill down, running
3 PC's and a radio or two 24/7 is somewhat noticeable to the
wallet these days, and it is not getting any easier!...

Then there is the chore of just finding the time to research
and mess with all this stuff...

Enough waffle from me...

Regards to All..

Dave Baxter.
G0WBX.




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