Tuesday, 23 August 2011

VirtualBox - virtually complete: part 1

My new Linux machine is almost complete now. It has been running for a couple of months. Since I lost my laptop along with the company I worked for, and haven't seen a reason to buy another one yet, the Linux machine has become my main computing platform for just about everything.

However there are some things which can only be done on Windows. One is iTunes - I only use it as a backup for my iPhone, but for that it is indispensable. Another is the package that updates the navigation data for the plane. Then there is expensive software I bought for Windows and don't plan to buy again - Mathematica, CorelDraw and so on. Not to mention my HP printer/scanner which has no Linux driver. So I've had two machines sitting next to each other, with a  KVM switch to go back and forth when needed.

Of course the solution to this is obvious - virtual machines. I've been idly looking at VirtualBox, one of the open-source VM solutions, for a while. It took something odd to make me dig a bit deeper - the discovery that our electricity supplier (PG&E) has a web page where you can see your hourly consumption. It's fascinating to study, and one thing it showed is that my two desktop computers were accounting for about 60% of the house's background electricity usage. So, turn one of them off, instant 30% energy saving. (If only I could do something equally miraculous for the pool, which accounts for over half of our electricity).

I started by creating a second Linux system. That seemed less scary, though as it turned out it was harder than Windows. It's simple enough - tell VBox to create a virtual machine, then boot it with a Ubuntu CD in the drive and it pretty much goes all by itself. My plan for this VM was to use it as a web server for stuff I want to host at home, rather than through my web provider. It all went well, until I tried to set up a "shared folder".

In its pure form, the VM concept means that the VM runs in complete isolation in a bubble inside the real operating system. This is fine until you do actually want to share stuff. You can do it over the net, using FTP or whatever, but even that isn't "out of the box". By default, Vbox creates VMs using internal NAT addresses, so there is no way to access the VM from anywhere else, including the host. That can be fixed with a couple of clicks, selecting "Bridged Adapter" in the "Attachedto" drop-down, instead of "NAT". But still, it's a clunky way to do things.

So you can also create a "shared folder". This is just a regular directory on the host system, but it looks like a remote filesystem to the guest. It's easy enough to set up, but I just could not get it to work. I successfully mounted it just once. After that, attempts to mount it always failed with "no such device" (or some such). Even deleting it and creating a new one didn't work.

Finally I discovered that, because I'd ticked the "auto-mount" box, it was being automatically mounted in /media. Well, duh, I suppose.

With that done, my Linux VM was usable. Fortunately, because it turns out in my main (host) system, Firefox had autoupdated itself to V6 - and the Flash player doesn't work an more. No more stock charts from Google, no more news video clips from the BBC. This seems to be a problem that a handful of people have run into, with no solution. So for now, I just use an older version of Firefox running inside the Linux VM whenever I need Flash.

The next step was to install a Windows VM. But this is already too long, so that will be for another time

No comments: