KVM windows guest time changing

[adam.james17]

How to fix the kvm guest of windows getting time change every reboot.
if we set internet time or manual time its still change to another timing.

 

[Stoiko Ivanov]

* did you set the vm OS-Type to Windows? (otherwise PVE presents the clock as UTC, where Windows expects localtime)
* if not - what kind of time-change do you see? (what time should be set, what time does the machine actually have)?
* please post the vm's config

 

[adam.james17]

* yes its selected as windows 2012
* changing time to IST and it auto change back to US time GMT-4

 

[dcsapak]

maybe this is the issue? https://www.thewindowsclub.com/set-time-zone-automatically-windows-10

 

[adam.james17]

maybe this is the issue? https://www.thewindowsclub.com/set-time-zone-automatically-windows-10

its not

 

[dcsapak]

ok but we do not change the timezones of the guests (this would be a very hard thing to do ... ) so i think this is a guest problem -> check inside windows
also i found a thread on the microsoft forums where users report the same problem but on real hardware: https://answers.microsoft.com/en-us...ndows-10/46f75346-bd56-44d1-aa5e-b39d48b085ff

 

[Mecanik]

Several articles regarding this issue already, including me experiencing it.

 

[uriel]

Hi,

I have just found the solution:
Proxmox handles windows VM by setting "Use local time for RTC" to Default (Enabled for Windows).
In this case, your Proxmox time zone MUST match your windows timeZone.

Otherwise

If you want to mixte timezones in your setup, you MUST set "Use local time for RTC" to No in Proxmox, and TimeZoneInformation to RealTimeIsUniversal in your Windows VMS Register.

By running as administrator:

reg add HKLM\SYSTEM\CurrentControlSet\Control\TimeZoneInformation /v RealTimeIsUniversal /t REG_DWORD /d 1

and Voilà !

SOLVED.