Problems with time sync on Windows Guests

[felipefonsecahy]

Hi Everyone!

I'm new here on the forum, so I'm sorry if the question is very basic.

I have a VirtualBox installed in Xubuntu and created a WindowsServer 2012 VM.

I configured a NTP client on Linux Host and in the guest machine i can't configure ntp manually (the "Internet Time" tab, located on the control panel does not appear). I believe that guest machine synchronizes time with host.

And I am observing very strange behavior on the guest machine. During its operation, I notice that the passage of time becomes faster or slower to try to synchronize the time with host. That is, the time oscilates and the time get ahead and early but never synchronize correctly.

Has anyone seen this behavior?

It's possible to disable timesync between guest and host, and configure ntp client directly on guest?

Thanks a lot and forgive me for my bad English.

[scottgus1]

Your English is very good and is quite understandable to me (English is my mother tongue).

A Virtualbox guest is a separate "PC" from the host, no time syncing can happen until Guest Additions are installed in the guest. Then Virtualbox provides time sync, which can be edited with 'vboxmanage' commands.

If a network to the guest is provided where internet is available, the guest may also get internet-based time corrections, typical of a stand-alone OS. Guest Additions can undo this 3rd-party syncing.

Start the guest from full power off, not save-state. Run until you see the problem happen, then shut down the guest from within the guest OS if possible. If not possible, close the Virtualbox window for the guest with the Power Off option set.

Please right-click the guest in the main Virtualbox window's guest list, choose Show Log. Save the far left tab's log, zip the log file, and post the zip file, using the forum's Upload Attachment tab.

Please right-click the guest in the main Virtualbox window's guest list, choose "Show in Explorer/Finder/File Manager". In the window that opens, zip the guest's .vbox file, and post the zip file, using the forum's Upload Attachment tab.

[felipefonsecahy]

Apparently the Guest Additions is installed (in the previous post, I said that I had created the machine to facilitate the explanation, but the machine already existed).
So, can Guest Additions cause this behavior?

[felipefonsecahy]

Hi Everyone!

I solve my problem follow the steps described in the link bellow:

https://superuser.com/questions/742924/ ... -if-so-how

After, i setup a NTP sync, as link bellow:

https://support.microsoft.com/en-us/hel ... ows-server

Thanks!