1 First steps

This is equivalent to pulling the power plug on a real computer without shutting it down properly. If you start the machine again after powering it off, your operating system will have to reboot completely and may begin a lengthy check of its (virtual) system disks.

As a result, this should not normally be done, since it can potentially cause data loss or an inconsistent state of the guest system on disk.

As an exception, if your virtual machine has any snapshots (see the next chapter), you can use this option to quickly restore the current snapshot of the virtual machine. Only in that case, powering off the machine is not harmful.

The “Discard” button in the main VirtualBox window discards a virtual machine’s saved state. This has the same effect as powering it off, and the same warnings apply.

1.8 Snapshots

With snapshots, you can save a particular state of a virtual machine for later use. At any later time, you can revert to that state, even though you may have changed the VM considerably since then.

You can see the snapshots of a virtual machine by first selecting a machine from the list on the left of the VirtualBox main window and then selecting the “Snapshots” tab on the right. Initially, until you take a snapshot of the machine, that list is empty except for the “Current state” item, which represents the “Now” point in the lifetime of the virtual machine.

There are three operations related to snapshots:

1.You can take a snapshot.

If your VM is currently running, select “Take snapshot” from the “Machine” pull-down menu of the VM window.

If your VM is currently in either the “saved” or the “powered off” state (as displayed next to the VM in the VirtualBox main window), click on the “Snapshots” tab on the top right of the main window, and then

either on the small camera icon (for “Take snapshot”) or

right-click on the “Current State” item in the list and select “Take snap- shot” from the menu.

In any case, a window will pop up and ask you for a snapshot name. This name is purely for reference purposes to help you remember the state of the snapshot. For example, a useful name would be “Fresh installation from scratch, no external drivers”. You can also add a longer text in the “Description” field if you want.

Your new snapshot will then appear in the list of snapshots under the “Snapshots” tab. Underneath, you will see an item called “Current state”, signifying that the

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Sun Microsystems VERSION 3.1.0_BETA2 user manual Snapshots, You can take a snapshot