What OS Combinations Work Best Together?

[Donald Darden]

I haven't tested every combination of host and guest OS, nor have I fully tested alternate VM solutions.  It would take far more effort than I have to offer to do this, but with the testing I've done so far, I have reached some surprising conclusions>

First, Linux distributions (recent ones, that is), provided good support for the role of host OS, and as expected, require only a thin amount of RAM (<300 MB) in order to function.

Second, VirtualBox seems to have it all - speed, stability, ease of use, and it's even free for the individual, which has kept me from exploring other VM candidates further.

Third, Windows works very well as a guest OS, and it has been remarked on by me and some others how responsive it is when installed and running in this mode.  I have not tried Vista, but reports are that it does very well as a guest as well.

One key factor in determining how well an OS runs as a guest is whether the Guest Addititions can be applied or not.  These are tweaks or programs that cause the guest OS to work better in a virtual environment.  My readings suggest that Virtual Additions are a Microsoft concept, and certainly, when installing Windows as a guest, you only need to install the Guest Additions, and it really improves performance.

There are also guest additions for Linux, but there often have to be compiled with the kernel source files and headers for inclusion in the Linux distro, and only a few distros come that way.  Many other distros are not distributed with the source code and headers.  In general, if you have a CD .ISO image or disk, it does not have the source files and headers.  If the image is a DVD, it may include the source files and headers.  You might be able to locate the source files and headers online, but many distros are a blend of sources, or built on other distros, and this is becoming a real problem in getting the precise souce and header files necessary to rebuild the kernel.

Kernel building is hardly a task suited for the average computer user anyway.  So in choosing a host, you have to make sure that the kernel is at least 2.6.16.  However, other sources indicate you may need an even more recent kernel, possibly as late as 2.6.22, to be sure that it can work well as host (You can use the command uname -a to see which kernel your distro has).  I can't seem to find a source that is absolutely certain on the precise version involved, but I do know that Knoppix 5.1.1 lacked it.

If anybody works out the kinks of getting source and headers, and building virtual additions into Linux, that would probably be a good discussion.  It's still over my head.

My best combination of host and guest have turned out to be Ubuntu using Virtualbox and Windows 2k Pro as guest.  This was really the easiest to do, and performance of both Ubuntu and Windows are outstanding on my older PC.  I have not tried Windows XP Home, but I expect it would be nearly the same.

My next best combination of host and gest was again with Ubuntu and using Win XP Pro.  This was not as easy, as I had to learn to turn on all the features of XP Pro in order for it to access the VirtualBox Shared Folders.  Other than that, performance for Ubuntu and Windows were both good.

Though not verified by me, several reports were found where others were very impressed with how well Vista worked in a similar configuration.  I would assume this was the Home Basic or Home Premium version, but it was not stated.

I was disappointed with the results of using Ubuntu as host and SimplyMIPIS as guest.  I picked the latter because it is suppose to come with the guest additions already built in, and while it performed well enough, it was unable to maintain sync between audio and video in the streaming video test.  The playback was nearly good enough, and on a faster PC, there would have been no evident problems.

The most disappointing results were with Ubuntu as host and Freespire as guest.  Freespire evidently does not have the guest additions, and I could not find the source and header files necessary to trying to rebuild the kernel, and the streaming video test was choppy and unwatchable.   

I would conclude that Microsoft's efforts must have helped with refining the Windows' Virtual Additions, which is why it's products work so well as guests.  A same quality of effort is not apparent for Linux distributions, and as a result, they are not quite as good when placed in the role of being guests.  That could change in time, but the other considerations is that faster and more powerful PCs will result in better performance for both hosts and guests.

And the final surprise was that my initial preference, which was to have Linux as host and run Windows in a virtual mode, has proven to be the best configuration of all.  I wanted that because I felt that Linux is possibly the better when it comes to evading external threats, but that you need the ubiquitous nature of Windows in order to retain your state of high productivity and for compatibility with existing applications and data formats.

[Donald Darden]

I booted up the Ubuntu 7.10 on my sdb1 partition, and was surprised because it was stuck at some rediculously high resolution that forced me to lean in really close to try and read what was on the screen.  Efforts to change the screen resolution were to no avail, as it just failed to change modes when I asked it to do so.  So I rebooted to the Ubuntu 7.10 install on my sdb2 partition, which was still set at 800x600, which works best for me.

Looking online for some information to help, I found that the /etc/X11/xorg.conf file is what tracks settings for the screen and other devices.  I tried to compare the settings for the /media/sdb1/etc/X11/xorg.conf and /etc/X11/xorg.conf files.  I finally decided just to copy the one from sdb2 over to sdb1 and see if that would fix the problem.  And it did, but I had to use the sudo mode and first remove the old file.  The reboot back to the sdb1 partition showed the problem resolved.

This is a lot better than having to reinstall an OS just because a small glitch comes up.  Since each install of Linux uses its own idea of a root partition, it is very easy to attempt this sort of rough and ready fix.  In fact, it is one of my strongest arguments to multiple installs of the same OS.  It sometimes works with Windows as well, but its adherance to recognizing partitions by letter can sometimes be a setback in this regard.

I could likely do the same thing across different installs of Linux, so it is not like you are locking yourself into just one version at the expense of playing with others. It just serves to point up another reason why multiple installs can have unexpected benefits.  Had I only had the one install, I would have had fewer options to explore as I attempted to deal with the issue that came up.