Backing up is easy: Snapshots

In the following screenshot, the "Snapshots" tab is open.

At any time, I can take a snapshot of the current state of the client. Later, the snapshot can be used to restore the client to the state of the snapshot. I took my first snapshot immediately after installing Windows XP and before installing any programs. Later, I took snapshots after installing major programs. If something goes wrong with the current state (virus, program corrupted, bad file, etc.), I can delete the current state and go back to an earlier good state.

Server installations use virtual computers. If the current state of the server goes bad and the server is down, a snapshot can quickly restore to a good state. Restoring by a virtual computer is much faster than reinstalling the OS, programs, and data on a real computer.

Export and import appliances.

In the following screenshot, the "File" menu is open.

The virtual computer, with its OS and programs, is called an appliance. In the "File" menu, the current state of the appliance can be exported. I did that and saved the large file (almost 6GB) on my backup hard drive. Later, if something goes wrong, I can import the good appliance.

Computer centers, with operators at many identical computers (e.g., on-line stores and call centers), use virtual computers to efficiently update all computers to the same state. Over a local network, an old appliance is removed and the same, new appliance is imported to all computers.

• From various websites, download and import other appliances.
Googling "virtualbox appliances" yields many websites with appliances for downloading. Usually, these are other flavors of Linux. Some appliances include programs for doing a specific task. Downloading and importing an appliance, avoids the effort to setup a virtual computer, install an OS, and install programs.

Conclusion

A virtual computer allows one to have his cake (run Ubuntu) and eat it too (run Windows).

I am new to virtual computers having started about three months ago. Other club members may have more experience and can add to my comments, especially regarding the use of VMware.
 

(Ed. Bill Young's talk was presented at the August 12, 2009 General meeting.)