local time for RTC option when VM acts as NTP itself

ieronymous

Active Member
Apr 1, 2019
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Hi

I am trying to figure out what to do about the local time for RTC option for a Vm (WinServ2019) which acts as an NTP and syncs time from an external source.
To my understanding, letting option as default, so enabled, makes VM thinks its bios clock is Proxmox's clock, right?
Should I disable it for this specific VM (if yes then what to input for the option below RTC start date - it has now) or it doesn t matter because windows server rules takes precedence from its theoretically real time clock?
I am asking because with esxi there is a guide pointing to uncheck an option to use hypervisors time as the Vms real time clock.

I really need to get how it works

Thank you
 
Last edited:
...... after a dozen of tries I think I figure it out.
Proxmox parameter needs to be set to off and at the same time inside the WinServ vm needs to alter the value of a registry word. You can add it (instead of searching your way into it among clicks) from powershell and the command
reg add HKLM\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\VMICTimeProvider /v Enabled /t reg_dword /d 0

Only with both the above changes I was able to input w32tm /query /source and have as a result the external time server I had configured earlier.

PS Now I have to find out if I need to change those values for the other servers too (SQL and RDS and a W10) or they will be able to acquire the time from the server via gpo policy.
 

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