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Question for NTP synchronization between Windows 10 Pro workstation and RHEL7.6 Server.

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Hi.
I have a question for NTP synchronization between Windows 10 Pro workstation and RHEL7.6 Server.

Workstation (DELL Precision 7920R) in Windows 10 Pro is a NTP Client and Server(DELL PowerEdge R740) in RedHat Linux 7.6 is NTP server. They are connected through a LAN cable (UTP, CAT5.e) and NTP setting is configured as follow.

  1. From Date and Time > Internet Time : Changed Internet Time Settings as the IP of NTP server

  2. From Windows Group Policy Configuration : Enabled Global Configuration Settings of Windows Time / Changed MaxPollInterval as 5 / Changed MinPollInterval as 2 / Enable 'Windows NTP Client' / Entered 'NTP_SERVER_IP,0x8'at NtpServer of 'Configure Windows NTP Client' / Changed Type to NTP of 'Configure Windows NTP Client'

  3. From Windows Services Configuration : Changed Startup Type of Windows Time to 'Automatic(Delayed Start)'

  4. From Windows Task Scheduler : Click 'Disable' for Synchronize Time

  5. NTP Server has active NTP Daemon, so it can send NTP packets to NTP client.


After applying these configurations (which i've learned from microsoft NTP explanation document), I checked time difference between workstation and server by entering 'w32tm /stripchart /computer:NTP_SERVER_IP' in command prompt.
The time synchronization work well as the NTP synchronizes every 4~32 seconds (based on Max,Min Poll Interval values). However, time difference increases 0.2milliseconds every 2 second, but actual time difference shown is smaller than that. (as shown in the screenshot)

So my questions are,
1. Why is there a 0.2milliseconds increase every 2 seconds in the first place?
2. If it's natural for NTP client to have time difference (0.2 milliseconds every 2 seconds), would there be any way to delete this difference from happening?(just by using Microsoft basic functions)


My speculations are, there be could be something wrong in my configuration / it is inevitable problem that Windwos OS suffers from / It's a problem of connection between Linux NTP Server and Windows NTP CLient / Real Time Clock(Hardware Clock) of workstation is not correct because C620 Chipset(Lewisburg PCH) is not precise in hardware clock ticking time/

Sorry for elaborating too much, but I would like to hear some advice regarding NTP synchronization.
Also, if there is any way I can contact with Microsoft developers of W32Time document (e.g. https://docs.microsoft.com/ko-kr/windows-server/networking/windows-time-service/windows-time-service-tools-and-settings), please let me know.

Thanks a lot.
Ho Sung Lee



windows-10-network
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mschiavon answered 12457159 commented
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Hi I just checked your detailed steps of setting GPO setting for NTP synchronization.
Thanks a lot.

Sadly, my environment is dealing with windows NTP client and Linux NTP server, so it seems like PDC configuration which is only related to Windows OS is not an option to me.
But, I really appreciate your detailed advice : )

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