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I have a virtual machine, with cent os installed, and everytime I sleep the host computer, the clock of the VM goes out of sync. I would like it to pick up the current time from virtualbox - which I would expect it to do naturally.

How can I force the clock to update from the host machine - or better still, have it stay in sync automatically?

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It should sync after a few minutes. If not, why not installing a NTP server on the host? Btw, Are you running Guest Additions? – bayindirh May 27 '13 at 7:05
I can not get network access to update from NTP server. I am not sure if guest additions is running. I am fairly sure it was installed. The VM has been provided to me at my job. – Billy Moon May 27 '13 at 7:09
I did a small research and everything I found tells that either Guest additions or Virtual Box itself syncs the time without intervention. You may got it disabled. The following command may enable it (Use on host): vboxmanage setextradata <vmname> “VBoxInternal/Devices/VMMDev/0/Config/GetHostTimeDisabled” “0″ – bayindirh May 27 '13 at 7:13
thanks @SilentStorm, that seems to have worked. – Billy Moon May 27 '13 at 7:39
you're welcome. Happy hacking! – bayindirh May 27 '13 at 7:52

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