[Solved] UTC clock

[boucherle]

I've virtualized a 2003 Server and a XP SP3 (Virtual Box 4.1.0).

On these two hosts, with or without Cnfiguration > System > Mother board > Advanced functions > "internal clock in UTC" (Sorry, I've translated from french), I'm not able to change the date and time on these hosts: a few minutes after I've changed day or time, it comes the same as the real machine (Seven Enterprise).

What's happened ?

Thanks for all.

Best regards.

[mpack]

No doubt both guest OS's are configured to get their time from an internet time server, which will obviously be current time. I'm talking about the guest OS's own configuration here, not the VirtualBox configuration of the VM.

[Perryg]

Or it could be the time sync of VBox.
You can switch this off with the following:

Code: Select all

VBoxManage setextradata [VMname] "VBoxInternal/Devices/VMMDev/0/Config/GetHostTimeDisabled" "1"

[boucherle]

Yes: vboxmanage setextradat is working, but a little strangely:
- minutes and seconds can be changed,
- but days months and years not.

This was usefull to find:
VBoxManage modifyvm "virtual machine name" --biossystemtimeoffset -<milliseconds>

So It's possible to change succesfully years, days, and so on.

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For the first answer: I make a test: my XP virtual out of network (network card desactivated in windows): "internal clock in UTC" don't change anything: the virtual machine don't want to have an other date and time than the real physical machine.
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Thanks for all.

Best regards.

[mpack]

For the first answer: I make a test: my XP virtual out of network (network card desactivated in windows): "internal clock in UTC" don't change anything: the virtual machine don't want to have an other date and time than the real physical machine.

Well on startup - of course not. The VM does not have an independant battery backed real time clock chip. So of course it takes its wall clock day/date and time from the host on startup, though as you've discovered that time can be offset by a specified amount. Then it may be corrected by a network time server, if it is configured to do so.

This is not the same issue as time synch, which may also be mentioned in the manual.