Hello,
Does anyone have a recommendation for how to disable all clock sync between Windows XP host and Windows XP guest? I wish to run some guests with the clock intentionally set ahead or behind the host. Thanks for any advice.
Disable Guest Clock Sync
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- Posts: 1
- Joined: 19. Nov 2009, 22:42
- Primary OS: MS Windows XP
- VBox Version: PUEL
- Guest OSses: WinXP, Debian
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- Volunteer
- Posts: 875
- Joined: 10. Oct 2009, 06:27
- Primary OS: MS Windows 7
- VBox Version: PUEL
- Guest OSses: Windows Server 2008 R2; Ubuntu 11.04; Windows 2000 Server; Windows XP
Re: Disable Guest Clock Sync
The manual (section 9.15) mentions a TSCTiedToExecution option, but I think that may cause clock skew.
Try this (undocumented) setting while the VM is shutdown:
<nanoSeconds> is a signed 64 bit integer being the offset from UTC (I think)
Set it to -86400000000000 to offset the VM time back one day.
The clock ticks will then still be in sync, but with an offset applied.
Edit: This can also be set using:
... this should set the VM clock to be in sync with the host clock, but <msec> (milliseconds) offset. Negative numbers put the VM clock in the past, positive numbers put the VM into the future.
Try this (undocumented) setting while the VM is shutdown:
Code: Select all
VBoxManage setextradata "My VM" "VBoxInternal/TM/UTCOffset" <nanoSeconds>
Set it to -86400000000000 to offset the VM time back one day.
The clock ticks will then still be in sync, but with an offset applied.
Edit: This can also be set using:
Code: Select all
VBoxManage modifyvm "My VM" --biossystemtimeoffset <msec>