how to remove time synchronization

Discussions related to using VirtualBox on Windows hosts.

how to remove time synchronization

Postby sankalpag » 9. Jan 2010, 09:22

guest win xp sp3
host win 7 pro

plz tell how to remove the time syncro between xp and 7. dont just copy paste the help

Thanks
sankalpag
 
Posts: 3
Joined: 5. Feb 2009, 07:44

Re: how to remove time synchronization

Postby sankalpag » 9. Jan 2010, 09:26

any help ?
sankalpag
 
Posts: 3
Joined: 5. Feb 2009, 07:44

Re: how to remove time synchronization

Postby vbox4me2 » 9. Jan 2010, 14:28

Remove the guest additions, as they do the syncing.
vbox4me2
Volunteer
 
Posts: 5222
Joined: 21. Nov 2008, 20:27
Location: Rotterdam

Re: how to remove time synchronization

Postby MarkCranness » 10. Jan 2010, 09:57

Rather than totally disable all Guest Addition features, you can just disable the time sync function.
You can turn the VirtualBox timesync off, but sometimes the VM then doesn't keep very good time and slips (it might only report 40 seconds of elapsed for every 60 seconds of elapsed real time, or it might be OK).

Or you can apply an offset to the time sync, so that the VM runs hours, days, years etc behind the host, but still maintains time sync.

Disable GA time-sync by editing the parameters passed to the VirtualBox Guest Additions Service (on Windows guests):
  • Open Registry Editor (Start menu>Run...>Type 'regedit' into the 'Open:' field>Click the OK button)
    WARNING: Incorrect editing of the registry can damage your system.
  • Navigate to: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\VBoxService
  • Double-click on 'ImagePath'
  • Change the 'Value data:' field to:
    Code: Select all   Expand viewCollapse view
    system32\VBoxService.exe --disable-timesync
  • Click OK
  • Either reboot the VM, or stop and then restart the 'VirtualBox Guest Additions Service'
    To restart the 'VirtualBox Guest Additions Service':
  • Right-click 'My Computer' on the desktop and select 'Manage'
  • Expand 'Services and Applications' and select 'Services'
  • Find service: 'VirtualBox Guest Additions Service' in the list
  • Right-click>Properties
  • Click 'Stop' button
  • Click 'Start' button
After these steps, timesync will be disabled.
To reenable timesync, repeat the steps but remove the --disable-timesync parameter.

Keywords: time clock sync synchronisation synchronization

OR A time offset can be set using:
Code: Select all   Expand viewCollapse view
VBoxManage modifyvm "My VM" --biossystemtimeoffset <msec>

... 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.
Last edited by MarkCranness on 12. Jan 2010, 07:33, edited 1 time in total.
MarkCranness
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: how to remove time synchronization

Postby sankalpag » 10. Jan 2010, 12:15

that VirtualBox Guest Additions Service was not present there :(
sankalpag
 
Posts: 3
Joined: 5. Feb 2009, 07:44

Re: how to remove time synchronization

Postby MarkCranness » 10. Jan 2010, 12:55

Are the Guest Additions (still) installed? (Is there a VirtualBox icon in the system tray at the bottom right inside the guest?)
If not, then time sync will be disabled.

The time is still set once-only anyway each time the VM boots, even when Guest Additions are not enabled:
At VM boot time, VirtualBox will set the virtual CMOS date and time based on the current host time.
Then, IF Guest Additions are installed (and timesync is not disabled), every 10 seconds an attempt is made to synchronize the time.

If you want the VM time to start at a different time, use the VBoxManage modifyvm "My VM" --biossystemtimeoffset <msec> command, which will give the VM a permanent offset, or reset the time in the VM using a startup command of some sort.
MarkCranness
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


Return to VirtualBox on Windows Hosts

Who is online

Users browsing this forum: No registered users and 37 guests