Re: [ntp:questions] Large offset and lots of time resets
Maarten Deen zq...@kf4nyy.ay wrote in news:Xns9E95E2074B3415r68mtnbtdvsdr@194.109.133.242: hal-use...@ip-64-139-1-69.sjc.megapath.net (Hal Murray) wrote in news:k4odnvhgatyt6_jqnz2dnuvz_jydn...@megapath.net: In article Xns9E95DA199C4695r68mtnbtdvsdr@194.109.133.242, Maarten Deen zq...@kf4nyy.ay writes: ... 23 Feb 20:42:53 ntpd[27664]: time reset +2.421296 s 23 Feb 20:52:05 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:58:31 ntpd[27664]: time reset +2.356457 s 23 Feb 21:04:48 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 21:14:26 ntpd[27664]: time reset +2.400477 s This goes on and on and on. And regularly ntp stops having connection, reach goes to 1 and builds up again. Never that it is a poll that's been missed, it is always back to 1 as if ntpd has started itself up again. I'm using ntp 4.2.4p4 on a Ubuntu box. Linux kernel 2.6.24. What's wrong in this setup? My guess is that the clock on your system is broken. Are you using some sort of power saving that is changing the CPU frequency? The computer is a server and is always on. Hardware is an AMD Athlon X2 and does lower the CPU frequency in powersaving. Have you tried a different clocksource? (google for linux clocksource) First I heard of it, I'll look into it. It is currently set to hpet and I see one link that suggests using acpi_pm. I'll try that. I've tried to change the clocksource but have been unable to. I have Ubuntu 10.4.2 and the available_clocksource lists both hpet and acpi_pm. Bu setting the clocksource to acpi_pm does not work. I've now booted with the command linux /boot/vmlinuz-2.6.32-29- generic-pae root=UUID=8e5256d1-0f66-438d-8f9d-d18bdcf7bf7a ro quiet splash clocksource=acpi_pm in grub.cfg, but the current_clocksource is still set to hpet. Am I missing something here? Regards, Maarten ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Large offset and lots of time resets
Chris Albertson albertson.ch...@gmail.com wrote in news:AANLkTim=uZ24Xbcu6jQB5F=F=xcuen3cf8hpvjikj...@mail.gmail.com: I've noticed that reach goes down not only in the case of a bad network connection but also if the data seems unreasonable by whatever criteria.That might explain why the polls keep working. I'm having the same exact problem currently with a GPS receiver that is not setup correctly. One thing I'd do is add at least two more server lines in your ntp.conf file. Along with the 0 pool server add lines for 1 and 2 at least. Then NTP can use it's clock selection algorithm I've had that before. But it gave the same issues. What kind of network connection is this? ADSL 8/1 Mbit Maarten ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Large offset and lots of time resets
On 2011-02-23, Maarten Deen zq...@kf4nyy.ay wrote: A while now I'm having some problems with my ntp setup. [snip] In ntp.log I continuously see lines like this: 23 Feb 19:09:51 ntpd[27664]: time reset +2.393091 s 23 Feb 19:21:52 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 Have you tried stopping ntpd, deleting your drift file and then starting ntpd? You may be able to improve your clock stability with one of these steps: * Starting ntpd with '-N' to increase its priority * Using a different clock source (as suggested elsewhere in this thread) * Using the right kernel boot args * Using a kernel compiled with HZ == 100 * Adjusting your kernel tick (not the HZ) as documented at http://support.ntp.org/bin/view/Support/KnownHardwareIssues#Section_9.1.6. -- Steve Kostecke koste...@ntp.org NTP Public Services Project - http://support.ntp.org/ ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Large offset and lots of time resets
In article Xns9E95DA199C4695r68mtnbtdvsdr@194.109.133.242, Maarten Deen zq...@kf4nyy.ay writes: ... 23 Feb 20:42:53 ntpd[27664]: time reset +2.421296 s 23 Feb 20:52:05 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:58:31 ntpd[27664]: time reset +2.356457 s 23 Feb 21:04:48 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 21:14:26 ntpd[27664]: time reset +2.400477 s This goes on and on and on. And regularly ntp stops having connection, reach goes to 1 and builds up again. Never that it is a poll that's been missed, it is always back to 1 as if ntpd has started itself up again. I'm using ntp 4.2.4p4 on a Ubuntu box. Linux kernel 2.6.24. What's wrong in this setup? My guess is that the clock on your system is broken. Are you using some sort of power saving that is changing the CPU frequency? Have you tried a different clocksource? (google for linux clocksource) -- These are my opinions, not necessarily my employer's. I hate spam. ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Large offset and lots of time resets
I've noticed that reach goes down not only in the case of a bad network connection but also if the data seems unreasonable by whatever criteria.That might explain why the polls keep working. I'm having the same exact problem currently with a GPS receiver that is not setup correctly. One thing I'd do is add at least two more server lines in your ntp.conf file. Along with the 0 pool server add lines for 1 and 2 at least. Then NTP can use it's clock selection algorithm What kind of network connection is this? On Wed, Feb 23, 2011 at 12:26 PM, Maarten Deen zq...@kf4nyy.ay wrote: A while now I'm having some problems with my ntp setup. I have simple comfig file: $ cat /etc/ntp.conf # /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help driftfile /var/lib/ntp/ntp.drift logfile /var/log/ntp.log server 0.nl.pool.ntp.org but the offset is usually around 2000 and the jitter hovers around 700: $ ntpq -np remote refid st t when poll reach delay offset jitter = = *217.67.231.25 193.67.79.202 2 u 43 64 377 23.005 2073.00 719.806 In ntp.log I continuously see lines like this: 23 Feb 19:09:51 ntpd[27664]: time reset +2.393091 s 23 Feb 19:21:52 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 19:25:10 ntpd[27664]: time reset +2.307869 s 23 Feb 19:35:17 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 19:40:40 ntpd[27664]: time reset +2.338134 s 23 Feb 19:51:24 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 19:55:43 ntpd[27664]: time reset +2.269268 s 23 Feb 20:01:27 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:11:09 ntpd[27664]: time reset +2.328620 s 23 Feb 20:20:17 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:26:50 ntpd[27664]: time reset +2.362413 s 23 Feb 20:34:17 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:42:53 ntpd[27664]: time reset +2.421296 s 23 Feb 20:52:05 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:58:31 ntpd[27664]: time reset +2.356457 s 23 Feb 21:04:48 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 21:14:26 ntpd[27664]: time reset +2.400477 s This goes on and on and on. And regularly ntp stops having connection, reach goes to 1 and builds up again. Never that it is a poll that's been missed, it is always back to 1 as if ntpd has started itself up again. I'm using ntp 4.2.4p4 on a Ubuntu box. Linux kernel 2.6.24. What's wrong in this setup? Regards, Maarten ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions -- = Chris Albertson Redondo Beach, California ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Large offset and lots of time resets
hal-use...@ip-64-139-1-69.sjc.megapath.net (Hal Murray) wrote in news:k4odnvhgatyt6_jqnz2dnuvz_jydn...@megapath.net: In article Xns9E95DA199C4695r68mtnbtdvsdr@194.109.133.242, Maarten Deen zq...@kf4nyy.ay writes: ... 23 Feb 20:42:53 ntpd[27664]: time reset +2.421296 s 23 Feb 20:52:05 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:58:31 ntpd[27664]: time reset +2.356457 s 23 Feb 21:04:48 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 21:14:26 ntpd[27664]: time reset +2.400477 s This goes on and on and on. And regularly ntp stops having connection, reach goes to 1 and builds up again. Never that it is a poll that's been missed, it is always back to 1 as if ntpd has started itself up again. I'm using ntp 4.2.4p4 on a Ubuntu box. Linux kernel 2.6.24. What's wrong in this setup? My guess is that the clock on your system is broken. Are you using some sort of power saving that is changing the CPU frequency? The computer is a server and is always on. Hardware is an AMD Athlon X2 and does lower the CPU frequency in powersaving. Have you tried a different clocksource? (google for linux clocksource) First I heard of it, I'll look into it. It is currently set to hpet and I see one link that suggests using acpi_pm. I'll try that. Regards, Maarten ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
Re: [ntp:questions] Large offset and lots of time resets
Maarten Deen zq...@kf4nyy.ay wrote: A while now I'm having some problems with my ntp setup. I have simple comfig file: $ cat /etc/ntp.conf # /etc/ntp.conf, configuration for ntpd; see ntp.conf(5) for help driftfile /var/lib/ntp/ntp.drift logfile /var/log/ntp.log server 0.nl.pool.ntp.org but the offset is usually around 2000 and the jitter hovers around 700: $ ntpq -np remote refid st t when poll reach delay offset jitter = = *217.67.231.25 193.67.79.2022 u 43 64 377 23.005 2073.00 719.806 In ntp.log I continuously see lines like this: 23 Feb 19:09:51 ntpd[27664]: time reset +2.393091 s 23 Feb 19:21:52 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 19:25:10 ntpd[27664]: time reset +2.307869 s 23 Feb 19:35:17 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 19:40:40 ntpd[27664]: time reset +2.338134 s 23 Feb 19:51:24 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 19:55:43 ntpd[27664]: time reset +2.269268 s 23 Feb 20:01:27 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:11:09 ntpd[27664]: time reset +2.328620 s 23 Feb 20:20:17 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:26:50 ntpd[27664]: time reset +2.362413 s 23 Feb 20:34:17 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:42:53 ntpd[27664]: time reset +2.421296 s 23 Feb 20:52:05 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 20:58:31 ntpd[27664]: time reset +2.356457 s 23 Feb 21:04:48 ntpd[27664]: synchronized to 217.67.231.25, stratum 2 23 Feb 21:14:26 ntpd[27664]: time reset +2.400477 s This goes on and on and on. And regularly ntp stops having connection, reach goes to 1 and builds up again. Never that it is a poll that's been missed, it is always back to 1 as if ntpd has started itself up again. I'm using ntp 4.2.4p4 on a Ubuntu box. Linux kernel 2.6.24. What's wrong in this setup? Regards, Maarten I once saw similar behaviour on a system which periodically ran a cron job which ran hwclock to set system time to the time from the hardware clock. ___ questions mailing list questions@lists.ntp.org http://lists.ntp.org/listinfo/questions
