On 2010-04-15, nemo_outis wrote:
> John Hasler wrote in
> news:874ojdmx12@thumper.dhh.gt.org:
>
>> Richard B. Gilbert writes:
>>> One possible solution is using radio controlled clocks. I have a
>>> wristwatch that uses a radio signal to correct itself. I also have a
>>> wall clock that do
On 2010-04-15, Chuck Swiger wrote:
> On Apr 14, 2010, at 2:15 PM, unruh wrote:
>> On 2010-04-14, Chuck Swiger wrote:
>>>
>>> The main point seems to be that a PPS signal should have much more reliable
>>> latency and less jitter, so when you examine the current clock and any
>>> adjustment, yo
[ Please forward to those who may be interested. Thanks. ]
==
2010 International Congress on Computer Applications and Computational
Science
CACS 2010
http://irast.org/conferences/CACS/2010
4-6 December 2010, Singapore
On 2010-04-14, Richard B. Gilbert wrote:
> nemo_outis wrote:
>> Rick Jones wrote in news:hq59ef$1p1$1
>> @usenet01.boi.hp.com:
>>
>>> nemo_outis wrote:
However, it would be irresponsible for Unruh and others here not to
point out that a much better timekeeping solution is readily
lhommedumatch wrote:
> The ACEB box is near my equipment.
> My PC and the ACEB box are both connected to a CISCO Catalyst 4510R.
The 4510R is a big-honking switch:
http://www.cisco.com/en/US/products/hw/switches/ps4324/ps5653/
http://www.compsource.com/mscs_images/epics/large/1011201476.jpg
W
Rick Jones wrote in news:hq5fhj$4e3$1
@usenet01.boi.hp.com:
> nemo_outis wrote:
>> Well, no, not exactly as you point out. For the (potential)
>> problems you point out (and we're both speculating here)
>
> Agreed, we are both speculating.
>
>> have little to do with using a GPS sensor, per s
lhommedumatch writes:
> I think that the reason why we use an external clock is to avoid loose
> of signal GPS. Apparently (discussion with crew) it happens and it
> depends of the weather, the position, the vessel and some unknown
> reasons.
But that is what the OCXO in the ACEB box is for. If
John Hasler wrote in
news:874ojdmx12@thumper.dhh.gt.org:
> Richard B. Gilbert writes:
>> One possible solution is using radio controlled clocks. I have a
>> wristwatch that uses a radio signal to correct itself. I also have a
>> wall clock that does the same. Both work very well.
>
> The
On Apr 14, 2010, at 2:15 PM, unruh wrote:
> On 2010-04-14, Chuck Swiger wrote:
>>
>> The main point seems to be that a PPS signal should have much more reliable
>> latency and less jitter, so when you examine the current clock and any
>> adjustment, you can use the PPS signal offset instead of
lhommedumatch writes:
> We have encountered problem with the ntp card of the clock several
> years ago. When too many clients are connected the clock used to have
> problems. May be this problem of latency and asymmetry comes from the
> ntp card.
Configure a pc as a timeserver with the ACEB as i
Richard B. Gilbert writes:
> One possible solution is using radio controlled clocks. I have a
> wristwatch that uses a radio signal to correct itself. I also have a
> wall clock that does the same. Both work very well.
They won't work very well inside a steel ship or far out to sea. They
use V
On 2010-04-14, lhommedumatch wrote:
> On 14 avr, 21:15, Terje Mathisen <"terje.mathisen at tmsw.no"> wrote:
>> John Hasler wrote:
>> > Richard B. Gilbert writes:
>> >> With a closed network the options are limited. ?With a place to site a
>> >> GPS antenna, you can install a GPS clock that will be
On 2010-04-14, Marc Fromm wrote:
> I have tried the suggestions in the multiple replies and my server (RedHat
> 5.2) still will not correct its time. After 14+ hours it was over 28 minutes
> behind.
Something is seriously seriously wrong with the machine. If it is not a
VM, then the hardware is
nemo_outis wrote:
> Well, no, not exactly as you point out. For the (potential)
> problems you point out (and we're both speculating here)
Agreed, we are both speculating.
> have little to do with using a GPS sensor, per se, but rather with
> cobbling up a *separate and independent network* for
lhommedumatch writes:
> This is ntpgmt aceb. they don't have the english version.
> http://www.aceb-elec.com/sofy_EXP320.htm
If those specs are to be believed that box has everything the OP
needs[1]: he just needs to get NTP from it to his machine(s). Thus the
problem is networking, not time. At
In article ,
s...@goes.nowhere.com says...
>
> In article <_didnrmzoqhxzlnwnz2dnuvz_q6dn...@giganews.com>, rgilbert88
> @comcast.net says...
> >
> > G8KBV wrote:
> > > In article ,
> > > cswi...@mac.com says...
> > >> On Apr 13, 2010, at 1:40 PM, G8KBV wrote:
> > >>> When I 'make buildkernel KE
On 14 avr, 01:42, John Hasler wrote:
> Richard B. Gilbert writes:
> > With a closed network the options are limited. With a place to site a
> > GPS antenna, you can install a GPS clock that will be accurate to
> > within +/- 50 nanoseconds.
>
> It occurs to me that the sort of fancy GPS that an o
On 2010-04-14, nemo_outis wrote:
> Rob wrote in
> news:slrnhsc00l.l0m.nom...@xs8.xs4all.nl:
>
>> nemo_outis wrote:
>>> True, one can chase any number of will-o-the-wisps such as the causes
>>> of the network latency and asymmetry, but that is not the central
>>> problem posed by the OP.
>>
>>
On 15 avr, 00:32, John Hasler wrote:
> lhommedumatch writes:
> > But I'm just responsible for one device. So the problem is how can I
> > be synchronized to ntpgmtaceb.
>
> Is the ACEB box near your equipment or elsewhere on the ship? Are there
> any switches or routers between you and it? Do yo
nemo_outis wrote:
Rick Jones wrote in news:hq59ef$1p1$1
@usenet01.boi.hp.com:
nemo_outis wrote:
However, it would be irresponsible for Unruh and others here not to
point out that a much better timekeeping solution is readily
available - a solution which is technically easy to implement.
Sla
lhommedumatch wrote:
> This is ntpgmt aceb. they don't have the english version.
> http://www.aceb-elec.com/sofy_EXP320.htm
http://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http%3A%2F%2Fwww.aceb-elec.com%2Fsofy_EXP320.htm&sl=auto&tl=en
for those who don't speak
lhommedumatch writes:
> But I'm just responsible for one device. So the problem is how can I
> be synchronized to ntpgmtaceb.
Is the ACEB box near your equipment or elsewhere on the ship? Are there
any switches or routers between you and it? Do you or your group
control it?
If it's nearby perha
nemo_outis writes:
> Given the lack of stroke of the OP and/or the recalcitrance of the
> ship's management, what is the likelihood that, having rejected
> something as simple as using a GPS receiver (which is likely *already*
> available on any modern oceanographic ship)...
As someone else pointe
lhommedumatch wrote in
news:54f12dc7-c737-482c-ac7f-b0f6885cf...@12g2000yqi.googlegroups.com:
...
> This is ntpgmt aceb. they don't have the english version.
> http://www.aceb-elec.com/sofy_EXP320.htm
The site says:
"Cet équipement peut être piloté par radio DCF77 ou GPS et offre une
précisi
On 14 avr, 19:54, Rob wrote:
> lhommedumatch wrote:
> > Hi,
>
> > Some news:
> > remote refid st t when poll reach delay
> > offset jitter
> > ==
> > *ntpgmtaceb .1PPS. 1 u 734 1024
On 2010-04-14, Rob wrote:
> nemo_outis wrote:
>> True, one can chase any number of will-o-the-wisps such as the causes of
>> the network latency and asymmetry, but that is not the central problem
>> posed by the OP.
>
> But it is!
>
>> In short, Unruh may be boring in his reiteration of his sim
Rick Jones wrote in news:hq59ef$1p1$1
@usenet01.boi.hp.com:
> nemo_outis wrote:
>> However, it would be irresponsible for Unruh and others here not to
>> point out that a much better timekeeping solution is readily
>> available - a solution which is technically easy to implement.
>
> Slapping a
On 2010-04-14, Chuck Swiger wrote:
> Hi--
>
> On Apr 14, 2010, at 9:08 AM, David J Taylor wrote:
>> I think you are correct in your final statement, but my understanding
>> (albeit limited) is that kernel PPS provides better performance, and is used
>> for a very limited set of operations (possi
nemo_outis wrote:
> However, it would be irresponsible for Unruh and others here not to
> point out that a much better timekeeping solution is readily
> available - a solution which is technically easy to implement.
Slapping a GPS onto a system on land in a "radio transparant"
structure may indee
I have tried the suggestions in the multiple replies and my server (RedHat 5.2)
still will not correct its time. After 14+ hours it was over 28 minutes behind.
I have a second server running fedora core 6, and from what I can see, the
configuration of ntp is the same and its time is always spot
Rob wrote in
news:slrnhsc00l.l0m.nom...@xs8.xs4all.nl:
> nemo_outis wrote:
>> True, one can chase any number of will-o-the-wisps such as the causes
>> of the network latency and asymmetry, but that is not the central
>> problem posed by the OP.
>
> But it is!
>
>> In short, Unruh may be borin
John Hasler wrote:
Richard B. Gilbert writes:
With a closed network the options are limited. With a place to site a
GPS antenna, you can install a GPS clock that will be accurate to
within +/- 50 nanoseconds.
It occurs to me that the sort of fancy GPS that an oceanographic ship is
sure to hav
Rob writes:
> The poster wrote that he wanted to sync to an available time source.
> He does not want to sync to GPS. It is clearly written why.
He made it clear that he cannot _install_ a GPS receiver. Putting an
existing one on the network is something else entirely.
However, he clearly has a
Random thoughts - sleep/hibernate mode on the client? Extreme/botched
interrupt coalescing on the client's NIC? Preferential treatment of
ICMP messages by the client or server TCP/IP stack? Preferential
treatment of ICMP messages by the Cisco switch (ISTR some issues with
NFS mounts over UDP on
John Hasler wrote:
> Richard B. Gilbert writes:
>> With a closed network the options are limited. With a place to site a
>> GPS antenna, you can install a GPS clock that will be accurate to
>> within +/- 50 nanoseconds.
>
> It occurs to me that the sort of fancy GPS that an oceanographic ship is
lhommedumatch wrote:
> Hi,
>
> Some news:
> remote refid st t when poll reach delay
> offset jitter
> ==
> *ntpgmtaceb .1PPS. 1 u 734 1024 377 29.779
> 1.182 0.228
>
> So still t
nemo_outis wrote:
> True, one can chase any number of will-o-the-wisps such as the causes of
> the network latency and asymmetry, but that is not the central problem
> posed by the OP.
But it is!
> In short, Unruh may be boring in his reiteration of his simple GPS
> solution, but that is beca
I'd suggest soem sanity changes to the configuration file:
> 31 # Undisciplined Local Clock. This is a fake driver intended for backup
> 32 # and when no outside source of synchronized time is available.
> 33 server 127.127.1.0 # local clock
> 34 fudge 127.127.1.0 stratum 10
Remove these l
Hi--
On Apr 14, 2010, at 9:08 AM, David J Taylor wrote:
> I think you are correct in your final statement, but my understanding (albeit
> limited) is that kernel PPS provides better performance, and is used for a
> very limited set of operations (possibly just timestamping the PPS signal).
> A
I am still confused as to why people recompile their kernel to put in
the kernel PPS. Just use the regular ntp devices like shm and a program
like gpsd to run pps from userland. I have no idea what advantages the
kernel PPS provides, certainly considering the pain of recompiling the
kernel. In fac
On 2010-04-14, David J Taylor wrote:
>> Hi all again.
>>
>> I'm still trying to follow the instructions at:-
>> http://blog.doylenet.net/?p=145
> []
>> I did have to go back into sysinstall, to download and install the
>> system sources, but after that, right up to the make buildkernel
>> comm
Hi,
Some news:
remote refid st t when poll reach delay
offset jitter
==
*ntpgmtaceb .1PPS. 1 u 734 1024 377 29.779
1.182 0.228
So still this problem in my LAN => because delay i
David Woolley wrote:
Marc Fromm wrote:
I am using RedHat 5.2 and running ntp-4.2.2p1-9.el5_4.1.
Obsolescent.
The server loses 1 second per minute.
As noted by others, that is not realistically correctable.
I've been checking it since I manually updated the time and after 2
hours it is 2
Dave Baxter wrote:
In article <_didnrmzoqhxzlnwnz2dnuvz_q6dn...@giganews.com>, rgilbert88
@comcast.net says...
G8KBV wrote:
In article ,
cswi...@mac.com says...
On Apr 13, 2010, at 1:40 PM, G8KBV wrote:
When I 'make buildkernel KENRCONF=PPSGENERIC'
Nowt happens, except a short error message
In article <82klvaf1h...@mid.individual.net>, sn...@lordynet.org says...
>
> G8KBV wrote:
> > So, what's missing, and where how can I get it.
> >
> > Anyone here know what went wrong, or do I go looking for a newbie
> > friendly f'bsd group (not found one of those yet.)
>
> I've just downloaded
In article , david-
tay...@blueyonder.co.uk.invalid says...
>
> > Hi all again.
> >
> > I'm still trying to follow the instructions at:-
> > http://blog.doylenet.net/?p=145
> []
> > I did have to go back into sysinstall, to download and install the
> > system sources, but after that, right up to t
In article <_didnrmzoqhxzlnwnz2dnuvz_q6dn...@giganews.com>, rgilbert88
@comcast.net says...
>
> G8KBV wrote:
> > In article ,
> > cswi...@mac.com says...
> >> On Apr 13, 2010, at 1:40 PM, G8KBV wrote:
> >>> When I 'make buildkernel KENRCONF=PPSGENERIC'
> >>>
> >>> Nowt happens, except a short err
David J Taylor wrote:
"Uwe Klein" wrote in message
news:iibg97-iiv@klein-habertwedt.de...
[]
There are these nice little USB Adapters available for small money
that provide a 40pin/44pin pata and an sata interface and come with
a "fitting" powersupply. ( forex : Digitus DA-70148-1 )
Very
"Uwe Klein" <> wrote in message news:4chg97-mj@klein-habertwedt.de...
[]
Thanks, Uwe. Yes, that might have been another approach - I can
imagine a USB DVD drive being quite handy. I haven't seen that
particular device before - very neat! On checking, though, it only
says it supports HDD
Hi
As I had told it during the main OS install, not to enable remote
logins, sshd and all that (as I do not intend to remote admin the thing,
as I have a KVM switch between 4 machines!) I think yet another
protracted full clean install would be needed to do much of that. :(
I do not have anothe
Hi.
[]
I was under the impression from prior comments that FreeBSD etc, was
good for older lower power machines. But if you need turbo nutterbuster
PC's to build it in the first place, just to enable PPS
The kettle call's.
Regards.
Dave B
As another datum for you, rebuilding the kernel
Dave Baxter wrote:
I'll try the 'build world' (Exact syntax?) thing, but perhaps this is
becoming less than practical, as the machine is a P3/700 with only
256MEG of Ram, and a 15Gig drive. (A Gateway E1400, one of these...
http://support.gateway.com/s/manuals/servers/eseries/8504419.pdf)
I
"Uwe Klein" wrote in message
news:iibg97-iiv@klein-habertwedt.de...
[]
There are these nice little USB Adapters available for small money
that provide a 40pin/44pin pata and an sata interface and come with
a "fitting" powersupply. ( forex : Digitus DA-70148-1 )
Very usefull for systems tha
Marc Fromm wrote:
I am using RedHat 5.2 and running ntp-4.2.2p1-9.el5_4.1.
Obsolescent.
The server loses 1 second per minute.
As noted by others, that is not realistically correctable.
I've been checking it since I manually updated the time and after 2 hours it is
2 minutes and 1 second
Chuck Swiger wrote:
If you add a server line, then you also need to add a restrict line like:
restrict time-nw.nist.gov
He's using an out of the box, or close to it, RedHat configuration. You
can assume that the restrict settings will work, and looking at the
configuration, I think they
David J Taylor wrote:
No, there's no CD or DVD drive on this PC. I did try installing FreeBSD
over the network, but on booting from a memory stick it only saw the
serial ports, and not the on-board network card. I thought this strange
as the install I did eventually do /did/ see the network c
Hi all again.
I'm still trying to follow the instructions at:-
http://blog.doylenet.net/?p=145
[]
I did have to go back into sysinstall, to download and install the
system sources, but after that, right up to the make buildkernel
command, all had gone as described.
So, what's missing, and
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