For those unfamiliar with the concept, virtualization is exactly what it sounds like: an entire computer is created in software, possibly with some help from the hardware. In practice, what this means is that you are able to have a “computer in a window,” as if it were any other program. The actual physical computer is called the host, and the virtual machine is called the guest. Note that virtualization is radically different from emulation; the former takes place when the host and the guest share their architecture (e.g. x86/amd64), the latter implies that they are different (e.g. a PowerPC host with an x86 guest.)

A very retro-futuristic word to describe the virtualization software on the host is hypervisor. Go figure.

My host of choice is, as it should be clear by now, MacOS X. As for my hypervisor, I like Oracle’s VirtualBox. It lacks Bootcamp support and is less polished than its commercial cousins, but it is distributed for free. With the current state of affair, that’s nice. Besides, I only need it for the occasional Windows test and for Unix-like guests, so I don’t have to rely on any fancy 3D acceleration (which VirtualBox apparently supports, anyway.) One last thing to note: VirtualBox runs on MacOS X, Linux, Windows and Solaris. I am going to refer to its OS X version, even though it shouldn’t be that different on other platforms.

Let’s get to the point. When you run a virtual machine (VM from now on) you usually get the “computer in a window” I described earlier. That’s great for graphical operating system such as Windows or Linux with X, but if you are running a text-only system such as Linux without X, what’s the point? You could save precious CPU and GPU time on your host by not having it display anything, effectively by running in the background, and accessing the VM through SSH or something similar. That’s when you want to use a headless VM.

Running it is astonishingly simple. VBox gives specific terminal commands to handle any aspect of the VMs. A list of available VMs can be obtained as follows:
octavarium:~ jollino$ VBoxManage list vms
Oracle VM VirtualBox Command Line Management Interface Version 3.2.6
(C) 2005-2010 Oracle Corporation
All rights reserved.

"Windows 7" {933835d0-d0d8-4bfc-83bc-85531e756cdd}
"Slack" {3a4f9f6a-da6b-40b5-8f4d-850937ffcd21}
"Debian" {2a0647aa-6444-4429-b022-42e76ee1bade}


The string in quotes is the human-readable name (that the user chooses when creating the VM), and the funny numbers are a unique ID for that machine.

Starting any of them in headless mode is as simple as running the VBoxHeadless command:
octavarium:~ jollino$ VBoxHeadless -s Slack &
[1] 425
octavarium:~ jollino$ Oracle VM VirtualBox Headless Interface 3.2.6
(C) 2008-2010 Oracle Corporation
All rights reserved.

FreeTSD: failed to destroy key: Undefined error: 0
VBoxHeadless(425,0xb058b000) malloc: *** error for object 0x11c700: double free
*** set a breakpoint in malloc_error_break to debug
Listening on port 3389.

Note that it doesn’t fork to the background by default. Forcing it to do so avoids abruptly stopping the VM should the terminal itself be accidentally closed. The errors mentioned are harmless.

If you need the “computer in a window” function, you can access the VM by using any RDP client and having it connect to port 3389 on the host. On OS X, I suggest CoRD. It’s important to make sure that the RDP client’s configuration matches the video output of the VM. I stumbled on this at first: CoRD expected a 1280 x 1024 screen, but the Linux console was set to 1024 x 768. This led to weird visual glitches, since VBox doesn’t seem to correctly communicate the screen resolution to the RDP client. The nice thing is that the RDP pipe is active even when the machine rebooting, because it’s handled by VBox itself.

Of course, if you run a VM in headless mode, you’ll typically only use RDP when needed. SSH works just as fine, and trust me, the whole thing feels faster without a chunky VM window in the way!

I happen to live in the Province of the Empire, in a country I oftentimes call “the third world of technology.” No way to rent movies online – or through the mail, for that matter –, no Pandora.com or Last.fm to easily find new music (the latter is available on a paid-membership basis; the former is simply forbidden), no iBooks when the iPad comes out, and so on. I live in Italy.

I am also a happy Mac and iPhone user. Not an evangelist, not anymore at least: I will praise how durable and enjoyable Apple products are, but I won’t urge anybody to buy them. I will, however, talk about them to people who ask me. After close to ten years as a Mac user (I do remember MacOS 9.2 and MacOS X 10.0) and years of previous experience with Linux systems, Apple has become an invaluable provider of my daily computing. OS X allows me tinker with the underlying UNIX system with ease while being extremely user-friendly with the rest of the user interface. As a web developer, it’s the closest thing to perfection I can think of.

When the iPad was announced, I was following Steve Jobs’s keynote through Engadget. I gradually turned from skeptic to disappointed: what, a big iPhone? A few hours later, a friend of mine summarized such feelings as: “I was hoping for a laptop replacement, and he just announced a tray. An iTray.”

A few days later, however, an article on a blog shone light on the matter: most of us computer people probably wouldn’t have much for a device like that. I’d personally much rather use my 13-inch MacBook Pro rather than an iPad, as it’s a full-fledged computer onto which I can install any program I want, with which I can multitask and that has a physical keyboard. I do sometimes use my MBP on the sofa, and while I agree that it’s not the most perfect experience, I’m willing to trade comfort for power.

People who do not have complex computing needs, though, will love the iPad. Take my father: he inherited the last PC I used, a glorious machine based on an AMD Duron 850 MHz CPU and 512 MB of memory. It runs Windows XP, and it’s far exceeded its time. Components keep breaking, and they are becoming hard to find. Every replacement has to be second-hand, and considering the higher price compared to current parts, it’s probably best to just ditch the machine entirely and build a new one. That was the plan, until the iPad was announced.

See, my father isn’t very computer-savvy. In fact, all he does is using Firefox to browse the web and little more. He doesn’t even care about productivity suites, he just reads a few online newspaper, peeks at The Daily Kitten, browses YouTube and visits the occasional website that he might hear about. He doesn’t even use email, in fact his email address is forwarded to mine so any messages he might receive from his bank will be taken care of. Also, since his computer started acting very flaky, he barely turns it on at all; and he doesn’t like sitting at the desk for long, and has no intention of learning how a computer works, therefore he is often confused by the interface.

Here are the three alternatives:

1. he can spend about €350 for a new PC that will be possibly left to dust
2. he can spend about €550 for a Mac Mini that will also be possibly left to dust and which will require him to get used to OS X
3. he can spend no less than €450 for a cheap laptop whose battery will last a couple of hours and which will have a learnng curve to be climbed
4. he can spend some €450 for the smallest iPad available (I think that that’s the pricing it will get in Europe), which he can use on his sofa, outside and anywhere else there is a wirless network, and that will take little time to get used to

He has also been saying that he wants a digital frame – and that kind of scares me, considering that I have 40 GB worth of pictures and that I will be the one who has to go through them with him – and that’s something else that an iPad might double as.

The iPad is, effectively, a closed environment. Users cannot install anything they want on it, and Apple can censor and refuse any content it doesn’t see fit. In return, the experience is smooth and without hurdles. What works, works; what doesn’t work, just doesn’t work. Those of us who see that as a threat to freedom should talk with computer illiterates. They would be amazed at how many people are perfectly fine with the concept of “you just can’t, period.” For them, even the simple lack of multitasking can be extremely beneficial; and that applies to some of “us” too.

Even tinkerers like me can be perfectly fine with closed systems, once the “threat to freedom” argument is put aside. I have been using an iPhone 3G since September 2008, and aside from minor annoyances, it’s served me very well. Sure, it would be great to have a wifi stumbler with GPS tracking support, but I can live without it. Also, tethering has been finally enabled with my cellular operator, so that’s not an issue anymore for me. And while the lack of multitasking can be annoying at times, the increase in battery life allows me to get over it. Of course, everyone has different needs, and I certainly do not question that; but that’s why there are alternatives.

For instance, I have read complaints by people who bought iPods and were extremely disappointed to see that they needed to install iTunes on Windows, or were just out of luck when using Linux. I think that such complaints are petty, pointless and naïve: the fact that you haven’t made any research prior to purchasing a product does not mean that the product is mediocre. The real problem is that your workflow isn’t flexible enough to fit said product, whether by choice  (“I don’t want to install iTunes”) or by need (“there is no iTunes for Linux”.) But that’s a problem with your workflow, not a problem with the product. The good news, however, is that there are plenty of other MP3 players that can be mounted as if they were USB drives and will read any files that are copied onto them. And they’re also cheaper than iPods!

The same applies to music: songs can be purchased from many online stores other than the iTunes Store, and they will play just the same. If you are old-style like me, you can also still buy physical CDs, with a printed booklet and whatnot.

Some commenters are astonished that the same people who bash Microsoft have a different attitude towards Apple. That may be true – Microsoft has a history of forcing their products onto the computer industry at large, whilst Apple’s influence is recent and limited to specific media industries –, but the truth is that even the most bitter anti-Microsoft people eventually grow up and take up a healthier “live and let live” attitude: I do not need Windows, I don’t use it; OpenOffice perfectly replaces anything I might need to do with Office; and so on.

Now, if Apple manages to modernize the press industry, then it’s certainly good for them. Rest assured that DRM won’t last long: media is bound to be globalized, and I am confident that in a few years producers will realize that they will make much more money by allowing everyone on the planet to buy their movies/songs/books without resorting to artificial boundaries; pecunia non olet, said the Romans. By the time a movie is released in another part of the planet, those who were waiting for it might as well have gotten it illegally: why not cash that money?

And incidentally, Apple is often an innovator. It was the first company to believe in mass-distribution of music over the ‘net, and many others followed suit; it was the first to believe in having computers with only USB ports (the glorious iMac); it was the first to provide the masses with a usable graphical user interface (Windows 1, released two years later, was little more than MS-DOS with a colored border around the screen); and so on. Who knows what will happen with Light Peak…