VirtualBox
When I was beginning in software development, I worked for a firm which (among other things) sells a software application for creating plastic cards. That software was off-the-shelf, shrinkwrapped.
As you can see, the software had to be able to install itself easily and couldn’t use additional components. To make sure of it, every time we compiled a new distributable version we made compatibility tests: on my desk I had four machines, one for development and three older PCs for tests. One of the machines had a Windows 95, another a Windows 98 and the last one a Windows NT; and each of them had only that and the necessary drivers installed. Our software had to work on naked machines, and with each major upgrade we had to format the test machines and reinstall their operating systems, to make sure a perfect installation of our application. The process was so repetitive that I ended unwillingly memorising the serial numbers of each OS.
We managed to speed up the process quite a bit thanks to Norton Ghost: you could make an "naked" OS image file for each machine and after the installation tests of our application, we could reinstall the software from the Ghost image, which quite faster and automatic.
But it was still a pain.
I would have been really happy those days for virtual machine software: either it didn’t exist by that time or I didn’t know about it. For those of you who don’t know what I’m talking about, Para los que no sepáis de lo que hablo, las virtual machines are programs that create a virtual environment between your physical hardware and the operative system installed in that hardware; and in that virtual space you can install another operative system completely different to the one physically installed, in a completely sandboxed environment. You can have a Windows 2003 Server inside a Windows XP, for example.
It’s easier to do than it looks: you assign inside the hard drive of your machine a file that’s going to be the virtual machine hard drive; and you set an amount of RAM to the virtual machine (RAM that’s going to be substracted from your total, physical RAM avaliable, so you need to have plenty for this). You can also mount virtual CD or floppy drives, allow the virtual machine network access, etc. To install an OS you just have to mount an ISO file containing an auto-bootable OS and run the virtual machine. From that point, you simply follow the OS installation instructions as if, in fact, we were installing a new OS in a machine built inside our machine.
I’ve personally used two virtualisation environments: Microsoft Virtual PC, which its version 2004 is free (as in beer) (2007 version is not) and I’ve been quite satisfiied with it: it’s a great virtualisation software, intuitive and easy of use, and the one I use in my workplace.
And the one I’ve just tested at home is InnoTek VirtualBox, Open Source and free (as in freedom). For me at least, the later is more important: I frankly don’t see myself capable of understanding, much less modifying, the source code of one of these things.
Right now I’m writing this entry from a virtual machine made with VirtualBox and running an Ubuntu Dapper Drake. No, I’m not going to the light side: it simply was the ISO file most at hand at the moment to test VirtualBox. In fact, my target for the next days is installing Vista. Long life the dark side! =)
So if you didn’t know virtualisation software, my advice to you is to give it a try: it’s simple to setup, intuitive to use and thanks to this technique we’ll have a safe environment to tinker with harmlessly.
