Windows 10 and 2016 time keeps rapidly changing when running as Hyper-V VM

We have a 2012 Server running Hyper-V. I have 3 VMs running under it. Win 2016, Win 8.1, and Win 10. The W2016 and W10 VMs are both experiencing an issue whereby the date/time are rapidly switching back and forth between the host time and some date/time back in 2015.

Some facts.
The problem goes away if the W32time service is disabled on the affected VMs.
We do not see this issue on VMs with earlier versions of Windows.
The host and VMs are only in workgroups.
None of the machines (host or VMs) are a DC.
I've reproduced this exact behavior on another host.

Any input on this time sync issues would be very welcomed
Who is Participating?
This is a known problem of win10/server 2016 and I have seen it discussed in a lot of forums. There does not seem to be a solution, yet. As a workaround, we have disabled that service, too and use scheduled tasks to sync the time.
Life1430Sr EngineerCommented:
Can you run w32tm /query /source on culprit machines keeping windows time service running?
Just a guess - with VMWare it's a common VM configuration problem to have some time keeping service like W32time or native NTP active and concurrently sync the time with the VM host machine. Such a configuration is the most reiable way to wreak havoc to the time syncof the VMs.

Have you disabled the time sync to the VM host ?

I usually disable it and use a lassic NTP client (see my article on NTP ...) for timekeeping. That usually works flawless.

(BTW: I've experienced enough trouble with that crappy W32time in NTP mode to evade that scenario whenever I have a chance to ...)
Improve Your Query Performance Tuning

In this FREE six-day email course, you'll learn from Janis Griffin, Database Performance Evangelist. She'll teach 12 steps that you can use to optimize your queries as much as possible and see measurable results in your work. Get started today!

kemberdAuthor Commented:
Update (sorry for the delay). I daren't run w32tm to work out the source. I've left Hyper-V time sync on as this sets the correct time. I have to leave Windows Time Service disabled otherwise the time flip flops between the correct time (as set by Hyper-V) and the rogue time (that looks like the date/time that the VM was built) as set by w32tm.
This is a bug ni the time service on win10/server 2016 - inform Microsoft if you have the time.
The flip-flop-behaviour is expectend - it's always a bad idea to concurently run multiple timekeeping services. I'd recommend to try droping Hyper-V's time sync and use a native NTP client for that. See my article on NTP basics for more details.
Frank, using multiple time sources will not let it flip flop like that. He writes, it flip-flops between the "correct time (as set by Hyper-V) and the rogue time (that looks like the date/time that the VM was built)". That phenomenon is known but is has nothing to do with multiple time services but it is a bug in the win10 time service and vanishes if that one is deactivated.
OK - that may be. Anyhow I've observed very erratic system time behaviour even on real machines if there were two timekeeping services active (native NTP client and W32time in that case).

To be more basic:
  • I'd definitvely expect havoc whenever that case of two timekeepers comes to life.
  • The actual emerging symptoms of temporal disorder madness depend on the actual circumstances.
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.