在 2013年11月25日星期一UTC+8下午10时36分19秒，Martin Burnicki写道： > [email protected] wrote: > hello : > I had recently start a work about > ntp service ,my friends and me use > windows and linux to sync time in ntp.we > could use w32time service to > sync linux in ntp. I hope the Linux machine is > the NTP server, and your Windows machine is the NTP client. Linux and other > Unix-like systems are usually much better timekeepers than Windows is. > In > windows we could I found that in the registry： > > HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config\ > > MaxAllowedPhaseOffset may be could set the offset time between the > local > time and the server that they will be synchronize. If out of > range of > MaxAllowedPhaseOffset in seconds ,they synchronize,otherwise > not. But I > have a question that Is there a paremeter in ntp service > that control the > offset like in registry above in windows. As has been noted by others here, > ntpd tries to slew the system time smoothly if the estimated time difference > is below a certain limit, and just steps the system time if if the determined > offset exceeds this limit for some time. The limit is usually 128 ms, but can > be changed. Unfortunately you don't tell which Windows version and which > version of the NTP service you are using. If you are encountering problems > getting the Windows time adjusted properly by ntpd then a a Windows bug can > be the reason why. Some Windows versions don't apply small time adjustments > to the system time at all. For example, if NTP applies an adjustment less > than 16 ticks to the Windows time this is simply ignored by Windows. However, > NTP expects the adjustment to have some effect, but if there is no effect > then the next time comparison yields a much larger difference than expected, > and thus causes another adjustment which is probably larger than necessary. > As a summary this can cause large swings in the time adjustment values. A > developer version of the NTP package contains a workaround for this Windows > bug. The report and fix are discussed here: NTP Bug 2328 - Vista/Win7 time > keeping inaccurate and erratic https://bugs.ntp.org/show_bug.cgi?id=2328 The > bug report contains a link to the Microsoft support web page explaining the > bug: SetSystemTimeAdjustment May Lose Adjustments Less than 16 > http://support.microsoft.com/kb/2537623 Even though the MS report only > mentions Windows 7, the Windows Server 2008 kernel is similar to Windows 7 > and has probably the same bug. So if you want to give it a try you can > download a developer version of the NTP package which includes a workaround > here: http://support.ntp.org/people/burnicki/windows/ You should try the > release version first. Just unzip the ZIP archive, stop the NTP service, copy > all extracted files over the files in your NTP installation directory (e.g. > C:\Program Files (x86)\NTP\bin\), and restart the NTP service. Also all newer > development versions of the NTP binaries should include this. We have found > that this version has greatly improved the resulting accuracy on Windows 7 > and Windows Server 2008 installations. Please note under Windows you should > configure all upstream servers with a line reading server aa.bb.cc.dd iburst > minpoll 6 maxpoll 6 where aa.bb.cc.dd has to be replaced with the host name > or IP address of your NTP server. Please don't use polling intervals below 6 > with the developer version since this prevents the workaround from working > correctly as discussed in the bug report. Also, if you don't limit the upper > bounds of the polling interval by "maxpoll 6" you may run into this bug: NTP > Bug 2341 - ntpd fails to keep up with clock drift at poll > 7 > http://bugs.ntp.org/show_bug.cgi?id=2341 On the other hand, the developer > version above configured with regard to the hints above has fixed the > timekeeping and significantly increase the time accuracy in a number of > installations of Windows 7 and Windows server 2008. Hope this helps. Martin > -- Martin Burnicki Meinberg Funkuhren Bad Pyrmont Germany
Windows system :Windows Server 2008 R2; Windows Server 2008 R2 ----NTP sync-----Linux Cent OS 6.2-----w32TIME Sync------Windows XP/7 _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
