[opensuse] Time server clients
We have been playing with high precision time in our non-internet-attached openSUSE systems. We use a high-end GPS receiver that provides a PPS signal on a serial port. Using gpsd and chrony, we have our openSUSE systems coming up as a Stratum One NTP server quite reliably after system boot. No humans. Just a nice ICON in the system tray that turns green when time is syncd. The goal was to have the system clock as accurate as possible so we can locate positions with high accuracy. The NTP was an afterthought (chrony, which is maintaining the system clock also can act as an NTP server): why not try to make other system components share this time synchronization? For example, there is a device that runs some embedded MS Windows. It timestamps it's data. Let's set it's clock as well. Initially, we thought that chrony on openSUSE had a problem. We just did not feel that the times reported by this Windows device looked so very accurate. And it was inconsistent. Sometimes it was decent accuracy. But sometimes not. Part of our method was to set up the Windows NTP client as an NTP source back in to the openSUSE machine (but not actually use the time - just report it). And we could see the unexpected difference in times. Damn. chrony has a problem. OpenSource, you know... Dig dig. Hunt hunt. Then... https://blogs.technet.microsoft.com/askds/2007/10/23/high-accuracy-w32time-r... Sigh. Has anyone else been effected by this problem? I understand that for most it is not a problem. But I find it incredible that when talking to a Stratum One server on a private network, decent time cannot be maintained by the Windows time service. If anyone else has been effected by this, was a solution found? There is a link to third-party solutions. We really do not want to rework someone else's box. If there is a better option. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Roger Oberholtzer wrote:
Has anyone else been effected by this problem? I understand that for most it is not a problem. But I find it incredible that when talking to a Stratum One server on a private network, decent time cannot be maintained by the Windows time service.
You must have been here already - NTP client for Windows? http://www.satsignal.eu/ntp/setup.html -- Per Jessen, Zürich (3.6°C) http://www.hostsuisse.com/ - dedicated server rental in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On Fri, Feb 26, 2016 at 2:10 PM, Per Jessen
You must have been here already - NTP client for Windows?
We are just now exploring that list. It is a last resort. If we modify another company's product and something goes wrong, our modification will be the focus point. Even if it is not the cause. We would like to avoid that if possible. Or if our customer sends the unit back to the maker (not us) and they remove our changes, we have to get involved in putting our changes back. But I suspect this will be the direction things take. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Per Jessen wrote:
Roger Oberholtzer wrote:
Has anyone else been effected by this problem? I understand that for most it is not a problem. But I find it incredible that when talking to a Stratum One server on a private network, decent time cannot be maintained by the Windows time service.
You must have been here already - NTP client for Windows?
Roger, I don't know to what extent this is covered/negated by the article you posted in the beginning: http://windows.microsoft.com/en-us/windows/set-clock#1TC=windows-7 Mind you, it does say "Your clock is typically updated once a week", so certainly no high accuracy here. -- Per Jessen, Zürich (1.4°C) http://www.hostsuisse.com/ - dedicated server rental in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On 02/26/2016 11:56 AM, Per Jessen wrote:
Per Jessen wrote:
Roger Oberholtzer wrote:
Has anyone else been effected by this problem? I understand that for most it is not a problem. But I find it incredible that when talking to a Stratum One server on a private network, decent time cannot be maintained by the Windows time service.
You must have been here already - NTP client for Windows?
Roger, I don't know to what extent this is covered/negated by the article you posted in the beginning:
http://windows.microsoft.com/en-us/windows/set-clock#1TC=windows-7
Mind you, it does say "Your clock is typically updated once a week", so certainly no high accuracy here.
In every instance where we had a large number of windows machines on a network where transaction processing took place we ALWAYS used a third party time client. I forget which one at the moment. This has largely gone away in Windows 7 and later as they fetch time from a number of user selectable sources, including microsoft's own time server or NIST time servers. You can add your own to the list HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\DateTime\Servers All my network clocks remain synced using my network server as the time source. -- After all is said and done, more is said than done. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On Fri, Feb 26, 2016 at 8:56 PM, Per Jessen
Roger, I don't know to what extent this is covered/negated by the article you posted in the beginning:
http://windows.microsoft.com/en-us/windows/set-clock#1TC=windows-7
Mind you, it does say "Your clock is typically updated once a week", so certainly no high accuracy here.
Believe it ot not, the initial default for the Windows time service is to update once per week. Even if it fails to do an update, it waits a week before trying again. We immediately changed it to something like 60 seconds just to see what happened. It did not help. We got over failures more quickly. But the accuract was still crap. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2016-02-26 14:01, Roger Oberholtzer wrote:
We have been playing with high precision time in our non-internet-attached openSUSE systems. We use a high-end GPS receiver that provides a PPS signal on a serial port. Using gpsd and chrony, we have our openSUSE systems coming up as a Stratum One NTP server quite reliably after system boot. No humans. Just a nice ICON in the system tray that turns green when time is syncd.
The goal was to have the system clock as accurate as possible so we can locate positions with high accuracy. The NTP was an afterthought (chrony, which is maintaining the system clock also can act as an NTP server): why not try to make other system components share this time synchronization? For example, there is a device that runs some embedded MS Windows. It timestamps it's data. Let's set it's clock as well.
Initially, we thought that chrony on openSUSE had a problem. We just did not feel that the times reported by this Windows device looked so very accurate. And it was inconsistent. Sometimes it was decent accuracy. But sometimes not. Part of our method was to set up the Windows NTP client as an NTP source back in to the openSUSE machine (but not actually use the time - just report it). And we could see the unexpected difference in times. Damn. chrony has a problem. OpenSource, you know...
Dig dig. Hunt hunt. Then...
Hum. At least vmware reccomends not to run an ntp client, or equivalent, inside virtualization. To run it only on the host system, then configure the guest tools to sync time with the host. Of course, I'm guessing that you talk of a virtualized Windows inside your Linux machine. But perhaps I guessed wrong. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iF4EAREIAAYFAlbQVxoACgkQja8UbcUWM1xaDAD/WVoKI1FDPoBhfCv3pq1bjeV8 igOL9Eq7UjA5hDsGRcMA/1G1/5EUfrd7ZmfqxOIUayWoF0YblhWVFFweracGLj7e =mom+ -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On Fri, Feb 26, 2016 at 2:46 PM, Carlos E. R.
Of course, I'm guessing that you talk of a virtualized Windows inside your Linux machine. But perhaps I guessed wrong.
It is a physical box that contains cameras, lasers and such that measure road marking retro-reflectivity and such things. Not virtualized. It is managed via network control by the openSUSE system. We want to improve time synchronization between the two system to try to improve data synchronization beyond what was delivered. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2016-02-26 14:54, Roger Oberholtzer wrote:
On Fri, Feb 26, 2016 at 2:46 PM, Carlos E. R. <> wrote:
Of course, I'm guessing that you talk of a virtualized Windows inside your Linux machine. But perhaps I guessed wrong.
It is a physical box that contains cameras, lasers and such that measure road marking retro-reflectivity and such things. Not virtualized. It is managed via network control by the openSUSE system. We want to improve time synchronization between the two system to try to improve data synchronization beyond what was delivered.
Ah, I see. I would then try to sync the windows side to external ntp sources (internet/intranet), and compare with the Linux side, to see if it goes better or not. If not, I would think that either the hardware is faulty, or the software ntp client/server on windows is faulty. At this step, I would try to boot a Linux on the windows side to see if it is capable of syncing time properly. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iF4EAREIAAYFAlbQXBMACgkQja8UbcUWM1yGFAD8DY8dLqKjoCdGl4kJtvHgsTgL N8SSW0Y0XA8AvYToReEBAJrufA9EpgT2pBXNfY/3mq5S/PsGSvP/ZrBdeXZphH1U =7mjx -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On Fri, Feb 26, 2016 at 3:07 PM, Carlos E. R.
Ah, I see.
I would then try to sync the windows side to external ntp sources (internet/intranet), and compare with the Linux side, to see if it goes better or not.
There is no internet in these systems. The GPS with the PPS is, in fact, more accurate anyway.
If not, I would think that either the hardware is faulty, or the software ntp client/server on windows is faulty. At this step, I would try to boot a Linux on the windows side to see if it is capable of syncing time properly.
I do not think there is a hardware or a software error. I think it is just that the Windows time service is crap. Apparently by design, as described in the MS note in the link. The reason I posted it here was (1) openSUSE seems to do the right thing, and good news is perhaps useful as well, and, (2) maybe someone else has tried to sync a Windows client against an openSUSE NTP server and found a way to get improved accuracy. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
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The reason I posted it here was (1) openSUSE seems to do the right thing, and good news is perhaps useful as well, and, (2) maybe someone else has tried to sync a Windows client against an openSUSE NTP server and found a way to get improved accuracy.
I ended up using true NTP server on Windows (I think, from Meinberg). -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2016-02-26 15:29, Roger Oberholtzer wrote:
On Fri, Feb 26, 2016 at 3:07 PM, Carlos E. R. <> wrote:
I would then try to sync the windows side to external ntp sources (internet/intranet), and compare with the Linux side, to see if it goes better or not.
There is no internet in these systems. The GPS with the PPS is, in fact, more accurate anyway.
I know, but you could enable it for diagnosis. [...] Pointless, I see now.
If not, I would think that either the hardware is faulty, or the software ntp client/server on windows is faulty. At this step, I would try to boot a Linux on the windows side to see if it is capable of syncing time properly.
I do not think there is a hardware or a software error. I think it is just that the Windows time service is crap. Apparently by design, as described in the MS note in the link.
Ah. Yes, I had that nagging, foggy, thought in the back of my mind. The article nails it, then. So, you need one of those sofware solutions mentioned in the article :-?
The reason I posted it here was (1) openSUSE seems to do the right thing, and good news is perhaps useful as well, and, (2) maybe someone else has tried to sync a Windows client against an openSUSE NTP server and found a way to get improved accuracy.
No, never. When I did need accurate but relative time, I used external hardware, and that was MsDOS, not Windows. That is, you need your software to read the time each time it needs it from external hardware, then stamps the internal data stream with it. If the clock is on the PCI bus, it is fast. The CMOS clock is accurate (one second), but reading it is not fast (one interrupt call). - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iF4EAREIAAYFAlbQaSMACgkQja8UbcUWM1ylyAD/cwLFi0iDSVgtBa4nFIlg1DBa GXscD/CYaDbVW9m8GwsBAJUvWD93g97d3PJrj+GT0d/Oe2oeUisAPIwJz+5y4MiQ =dkle -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
So, you need one of those sofware solutions mentioned in the article :-?
We have tried one and there was a nice improvement. We will fiddle more to see if it is consistent. Lesson learned: if it does not work, don't assume Linux/openSUSE :) (*) (*) I never do. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Roger Oberholtzer wrote:
On Fri, Feb 26, 2016 at 3:07 PM, Carlos E. R.
wrote: Ah, I see.
I would then try to sync the windows side to external ntp sources (internet/intranet), and compare with the Linux side, to see if it goes better or not.
There is no internet in these systems. The GPS with the PPS is, in fact, more accurate anyway.
If not, I would think that either the hardware is faulty, or the software ntp client/server on windows is faulty. At this step, I would try to boot a Linux on the windows side to see if it is capable of syncing time properly.
I do not think there is a hardware or a software error. I think it is just that the Windows time service is crap. Apparently by design, as described in the MS note in the link.
The reason I posted it here was (1) openSUSE seems to do the right thing, and good news is perhaps useful as well, and, (2) maybe someone else has tried to sync a Windows client against an openSUSE NTP server and found a way to get improved accuracy.
From years and years ago I seem to recall something about "\\net time set"? That was before I gave up on Windows, but I'm sure I tried to get it done on boot-up.
-- Per Jessen, Zürich (3.5°C) http://www.hostsuisse.com/ - virtual servers, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2016-02-26 17:23, Per Jessen wrote:
From years and years ago I seem to recall something about "\\net time set"? That was before I gave up on Windows, but I'm sure I tried to get it done on boot-up.
Sure; but have a quick read at the article he linked in the first post (it is quite short, actually), it is almost unbelievable. I didn't know it was that bad. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iF4EAREIAAYFAlbQgjYACgkQja8UbcUWM1wP6gD/UV3KpZsONao3nlIbRoxQCh+8 8auGNKwn9ewdNkTw9p8A/1VbUTuibbXc9+uh38SOSlFfiCkLtQuY0UiQB70ZzV1o =soZZ -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Carlos E. R. wrote:
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On 2016-02-26 17:23, Per Jessen wrote:
From years and years ago I seem to recall something about "\\net time set"? That was before I gave up on Windows, but I'm sure I tried to get it done on boot-up.
Sure; but have a quick read at the article he linked in the first post (it is quite short, actually), it is almost unbelievable. I didn't know it was that bad.
Yes, I skimmed it. Like I said, it's been very long since I've had any interest in or need to dabble with Windows - I think at the time I thought "\\net time set" would be good enough to keep the box somewhat aligned time-wise, but not on any sort of sub-second synchronisation. Not needed for office or home use and most sane individuals surely don't run anything time- or business critical on a Windows system :-) -- Per Jessen, Zürich (2.1°C) http://www.dns24.ch/ - free dynamic DNS, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
Per Jessen wrote:
Carlos E. R. wrote:
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On 2016-02-26 17:23, Per Jessen wrote:
From years and years ago I seem to recall something about "\\net time set"? That was before I gave up on Windows, but I'm sure I tried to get it done on boot-up.
Sure; but have a quick read at the article he linked in the first post (it is quite short, actually), it is almost unbelievable. I didn't know it was that bad.
Yes, I skimmed it. Like I said, it's been very long since I've had any interest in or need to dabble with Windows - I think at the time I thought "\\net time set" would be good enough to keep the box somewhat aligned time-wise, but not on any sort of sub-second synchronisation. Not needed for office or home use and most sane individuals surely don't run anything time- or business critical on a Windows system :-)
Even though Roger lives in Sweden, I'm sure he's quite sane and obviously the exception to prove the rule. -- Per Jessen, Zürich (2.0°C) http://www.dns24.ch/ - your free DNS host, made in Switzerland. -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2016-02-26 18:52, Per Jessen wrote:
Per Jessen wrote:
Yes, I skimmed it. Like I said, it's been very long since I've had any interest in or need to dabble with Windows - I think at the time I thought "\\net time set" would be good enough to keep the box somewhat aligned time-wise, but not on any sort of sub-second synchronisation. Not needed for office or home use and most sane individuals surely don't run anything time- or business critical on a Windows system :-)
I did, more or less, years ago. MsDOS, and Windows 95. Test beds, data acquisition... I didn't need to know what time it was with precision, but I did need to know the exact time interval from one sample to the next, down to the millisecond or better. We did not use the system clock, but one on the data acquisition board, via system bus.
Even though Roger lives in Sweden, I'm sure he's quite sane and obviously the exception to prove the rule.
:-) Guessing, he needs to use some commercial applications or hardware. He has both Linux and Windows platforms in the same setup, so it must be some thing like that. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iF4EAREIAAYFAlbQlpUACgkQja8UbcUWM1zH9QD9H0JDLRJZCzjqTO45aTRvTAWg /mMi0cMgbqevUMJ6InIA/imkBSAGr5Yfz8O2pZwEpOQFRP5cLLQdJAdAfnRoUJRb =fwWh -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
On Fri, Feb 26, 2016 at 6:52 PM, Per Jessen
Per Jessen wrote:
Even though Roger lives in Sweden, I'm sure he's quite sane and obviously the exception to prove the rule.
Sane indeed :) The box in question is a device that runs embedded Windows (http://roadsensors.madebydelta.com/products/ltl-m/). I recall asking the company why they chose Windows. Seems they wanted to use Linux, but the specific cameras they wanted to use only had Windows drivers. It is a very good high-end camera and so I understand their choice. But as I understand it, Windows has caused them problems. -- Roger Oberholtzer -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org
participants (5)
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Andrei Borzenkov
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Carlos E. R.
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John Andersen
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Per Jessen
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Roger Oberholtzer