http://time.is/ is constantly reporting my system clock as several seconds off (usually ahead) even if I freshly force synchronization of windows clock with some of the internet time servers (e.g. time.windows.com or time.nist.gov). This is complicating development of components integrating with remote servers that disconnects me if my timestamps are over second off. Our production HW have specialized HW clock provider with microsecond precision. I do not need anything like that in dev environment, but precision not worse than second is needed. Is there any public time server or reliable time synchronization utility that can achieve this?
EDIT1: I found and answer to different question that actually also answers my question. https://serverfault.com/a/489016. Among others it mentions:
- Microsoft does not guarantee sub-second accuracies using Windows Time (MS mentiones it here http://support.microsoft.com/kb/939322)
- NIST maintains list of third party time software producers here
Conclusion: for better precision than in order of 1 or two seconds you need to use third party time synchronization service.
If your machine is part of an Active Directory env, then its clock is automatically sync'd to the clock of your AD controller (which is likely sync'd to some other time source). So you should look to fix the time problem on the AD controller.
If you scroll 2/3 of the way down on this page: http://www.cites.illinois.edu/network/activedirectory.html it will tell you if your machine is in an AD domain.
If your machine is not in an AD, you can run
w32tm /stripchart /computer:time.windows.com
to tell how far out of sync your machine is with a time source (substitute time.windows.com with your time source).
If you want to resync to the time source immediately, run:
w32tm /config /syncfromflags:manual /manualpeerlist:time.windows.com w32tm /config /update w32tm /resync
and ofcourse you can re-run "w32tm /stripchart /computer:time.windows.com" to see if it really worked.