>Hi Kevin,
>
>I use Virtual PC (on Win7EE) for several appliances at the local high school. As long as there are pure M$ Apps it is fine enough. However, it makes trouble with any kind of linux derivates (S.U.S.E., Ubuntu, Red Hat).
>
>Therefore I am looking for alternatives...like Sun's Virtual Box. So...do you use Virtual Box with Linux and Win7 as base system? And if so, is it working well or are there any glitches?

I started using a new computer in February. After I built it, my first thought was to run Ubuntu Karmic as the base OS and then various Windows OSs as VMs using VirtualBox.

Before I started, I told myself the acid test would be viewing Flash videos in FireFox.

Karmic 64-bit installed fine. I also installed the alpha 64-bit Flash 10 plugin for FireFox from Adobe. Flash works, but CPU utilization is 25-30% of an i5-750 CPU (amongst all 4 cores, not just of one core).

VirtualBox installed fine on Karmic64. My memory is a little hazy but I think I was able to set up a VM and install Win7Pro64 on it.

From what I recall, there were two significant (for me) issues:

1. I specifically bought an nVidia graphics card for the new machine, because my understanding is nVidia is better supported by Linux. My base Karmic install was using the proprietary nVidia drivers. In the VM configuration I enabled as much RAM and hardware acceleration as possible. I'm trying to recall if I tried anything video-intensive in the Win7 VM but ISTR performance was not good. I admit I didn't look into any VirtualBox "guest additions" for Win7 on Ubuntu (if they exist). My understanding is guest additions, where present, basically paravirtualize certain drivers for better performance, as well as make desktop keyboard and mouse operations, and copy/paste more seamless between the base OS and VMs. So, I don't know if any such guest additions (again, if they exist for that combination) would help much.

2. If the base OS is Linux, then for VirtualBox you pretty much have to set up PulseAudio to be able to get decent, or any, sound out of the VMs. PulseAudio is a client-server architecture for audio, in some ways similar to X Windows for *n?x. This is non-trivial to set up, and about that time I started running into problems so I gave up on the whole idea of Linux as the base OS and switched to Win7Ult64.

The problems I ran into were hard hangs of the entire system when starting VirtualBox. This was repeatable, and fairly impressive when running on Linux so it was easy to blame VirtualBox. Turns out, on my machine with 8GB RAM, I had a bad stick in the 4 - 6GB range. In operations without VirtualBox the system never used or accessed anything above 4GB. However, when VirtualBox started up it started accessing the bad RAM and crashing the whole system hard.

So, VirtualBox on Ubuntu got a bad rap from me, initially. I didn't find out about the bad RAM until I installed Win7 64 bit, and it started periodically blue-screening on me. BTW MemTest86+ (note the + at the end) is a great tool for testing RAM, especially if you have more than 4GB).

At the moment I'm running Win7 Ultimate 64-bit as my base OS. So far I have set up only one VM, running Win7 Pro 64-bit. Both the base OS and VM have been completely stable. I'm using a base VM without guest additions as I don't need high performance graphics or sound in that particular VM. At some point I'll probably experiment with guest additions to see what they do. Sound in the guest is choppy/crackly at this time, without the guest additions.

On my host OS, Flash videos run with negligible CPU utilization - I believe as of the 10.1 plugin, Flash uses GPU hardware acceleration where available. My limited understanding is that this could be a long time coming to Linux - even 32-bit, let alone 64-bit. I haven't yet tried Flash video in the VM.

Virtual networking is fairly flexible but not well documented in VirtualBox. With a little trial-and-error I was able to set up a bridged network, so the VM and host OS can see each other in a virtual peer-to-peer network (the default is virtual NAT, so they can't). Virtual networking does have some limitations, I believe certain protocols are not supported reliably, or at all, in certain virtual networking configurations.

My understanding is your hardware (especially CPU) should support the latest virtualization technologies to get maximum performance and reliability, as well as the most ability to mix & match 32-bit and 64-bit hosts and guests.

So, with light use, I can report that Win7Pro64 runs fine in a VirtualBox VM on a Win7Ult64 host (on an i5-750 CPU with 8GB RAM). I imagine VirtualBox also runs well on Ubuntu, the bad experiences I had were due to the bad RAM, but more configuration is probably needed to get multimedia and/or specialized hardware working properly in guests. Sun (now Oracle) is a Unix/Solaris shop so support of VirtualBox on *n?x should be at least as good as Windows.

It's worth noting that VirtualBox is available for Mac OSX as well.

I think the choice of host OS depends on your most demanding work. If you're doing something intense like video editing, it doesn't make a lot of sense to do that in a VM as full access to the hardware probably isn't available - the VM may take a significant performance hit.

Returning to the focus of this thread, for malware resistance and the potentially greater safety of having a heterogeneous environment, a user might want to consider a Linux host with Windows guests.