My apologies, that was the wrong illustration. Onward!

Before we start, it should be noted that you don’t want to do this while your disk image is already in use. That is to say, if you’re running a virtualised host using this image, GTFO.

First, install the QEMU tools. In Ubuntu, you’ll find them in the qemu-kvm package. Whatever package your distribution ships which contains the qemu-nbd binary should be fine.

Load the nbd kernel module. Yes, I’m serious, the network block device module! (Note: All of the following commands require superuser permissions, so escalate your privileges in whatever way makes you most comfortable.)

modprobe nbd

Then run qemu-nbd, which is a user space loopback block device server for QEMU-supported disk images. Basically, it knows all about weird disk image formats, and presents them to the kernel via nbd, and ultimately to the rest of the system as if they were a normal disk.

qemu-nbd -c /dev/nbd0 <vdi-file>

That command will expose the entire image as a block device named /dev/nbd0, and the partitions within it as subdevices. For example, the first partition in the image will appear as /dev/nbd0p1.

Now you could, for instance, run cfdisk on the block device, but you will most likely want to mount an individual partition.

mount /dev/nbd0p1 /mnt

Gadzooks! Now you can muck around inside the filesystem to your heart’s content. Go ahead and copy stuff in or out, or if you’re feeling fruity, have some chrooty: chroot /mnt.

When you’re done, unmount the filesystem and shut down the qemu-nbd service.

umount /mnt
qemu-nbd -d /dev/nbd0

A simple — and importantly, public — interest metric that I’ve enjoyed in the past is Google Trends, and in particular, building a comparison between the major distros. It gives you a nice feel for the history of Ubuntu releases, press coverage and growing interest in the platform.

In terms of past performance, 7.10 and 9.10 have enjoyed the biggest spikes (against background noise of the time), while 8.04 LTS and 9.10 look pretty even as the highest peaks. It’s encouraging to see that 9.10 did so well.

But I wonder… how “big” will the 10.04 LTS release be? How much interest will it generate? How will the search and news spikes compare to previous releases?

Canonical has every reason to roll out the red carpet for this release, making a big deal of the release itself (Long Term Support, headline features, new theme and branding), launching new services (such as Ubuntu Enterprise Cloud support and the Ubuntu One music store), complementary announcements from partners, etc.

So… How big do you think the 10.04 LTS spike will be? Lay your bets in the comments. Just name a multiplier against the 7.04 spike — sitting at an even 2.0 on the search volume chart above — and by July we’ll see who nailed it!

Update: Fixed the Red Hat chart, thanks to David in the comments.

* They’re doing stupid shit with GNOME again, but they’ll grow out of the “differentiation means dicking with everything”, “design by finger-painting fiat” and “working with upstream is hard, let’s go shopping” stuff eventually. If Red Hat can see the light, surely Canonical can.

Ah, the life and times of a kernel hacker…

That’s what I would describe as “the hopes and dreams of a generation” (of Software Freedom lovers), and is the result of fantastic product definition, branding, genuine user excitement, years of incredible — and largely unsung — work of thousands of Debian developers (not to mention all the upstreams)… and a pretty substantial X factor.

Update: Whenever I talk about this chart in presentations, I always follow up with another chart which puts that incredible rising line in context: Ubuntu vs. Firefox. Interestingly, that chart is looking far less impressive today than it was last year. Which is great news… The rise and rise of Ubuntu is catching up to the star power of Firefox! Wow!

linux.conf.au 2009: Tuz

Impact: help prevent extinction of species

The Tasmanian Devil is a shy iconic Australian creature named for its
spine-chilling screech.  It is threatened with extinction due to a
scientifically interesting but horrific transmissible facial cancer.

This one is standing in for Tux for one release using the far less-known
Devil Facial Tux Disguise.

Save The Tasmanian Devil http://tassiedevil.com.au

Signed-off-by: Linux.conf.au Hobart Team <contact@marchsouth.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Surely udev could read and do something useful with /etc/iftab, even if it only provides a fraction of the functionality? Ubuntu successfully migrates the configuration, which is plenty good, but… ew.

I’d kick myself for becoming a “this is progress?! in my day…” curmudgeon, but this is a matter of protecting simplicity rather than pointless defense of “the old ways”.

Here’s /etc/iftab:

# This file assigns persistent names to network interfaces.
# See iftab(5) for syntax.

eth0 mac 00:15:c5:4a:71:98 arp 1
eth1 mac 00:18:de:03:3e:0d arp 1

While this is /etc/udev/rules.d/70-persistent-net.rules:

# This file maintains persistent names for network interfaces.
# See udev(7) for syntax.
#
# Entries are automatically added by the 75-persistent-net-generator.rules
# file; however you are also free to add your own entries.

# PCI device 0x14e4:0x1600 (tg3)
SUBSYSTEM=="net", DRIVERS=="?*", ATTRS{address}=="00:15:c5:4a:71:98", ATTR{type}=="1", NAME="eth0"

# PCI device 0x8086:0x4222 (ipw3945)
SUBSYSTEM=="net", DRIVERS=="?*", ATTRS{address}=="00:18:de:03:3e:0d", ATTR{type}=="1", NAME="eth1"

Photo courtesy SMH. Click the image for more.

So am I paranoid? Are invite-only events a necessary evil? Or should I let my curiousity overcome my principles? Hey, maybe one of those web 2.0 types could help me enable comments on my blog… — Rusty Russell, The foocamp clique?

… so I wrote down some of my musings for Rusty in an email, but then another discussion prompted similar thoughts, so I figured I’d blog about it. Of course, I did take the opportunity to suggest that Rusty try WordPress.

Pia and I went to baacamp (ha ha, “baa”, etc.) last year, being on the O’Reilly radar through my participation in OSCON and stuff like that.

Although it was sponsored by O’Reilly, it was very much a Nat thing compared to the “real” O’Reilly FOOcamps. They’re all very skewed towards Web 2.0 people and topics, but working with a different crowd who care about Freedom in different ways is great… It resets your reality distortion field, no matter how much clarity you start with!

It’s easy to forget, but linux.conf.au is also very cliquey, even beyond the silly name.

The invite-only thing is a bit weird, but if you have faith in the person doing the inviting, it’s very similar to the trust we invest in our FLOSS leaders, and the meritocracy which stems from them. For instance, Nat asks the people he invites to suggest other people, and uses that feedback very well. So, it’s like accepting or rejecting patches, and filtering good and bad contributors.

There’s also the problem of trying to inflict ideas about Software Freedom onto other, sometimes incompatible, structures and interactions. I think there are a lot of dangers to that route — largely because I’m not a crazy libertarian or genuine anarchist — and because I think misapplication of those ideas leads to the kind of behaviours that are well described in Geek Social Fallacies.

Finally, foocamp inspired greatness in its bizarro mirror image arch nemesis, barcamp. I had to say arch nemesis for effect. I like the idea of conference philosophies competing with each other in some kind of comic book Dante’s Inferno thinking man’s action-comedy.

If baacamp didn’t conflict with linux.conf.au, we’d be there in a jiffy. I’m falling in love with New Zealand and its inhabitants. We have a lot to learn from them, but also a lot to share. Some of our NZ friends are here this week, helping us turn Australia’s OOXML vote from “abstain” to “no” — hooray!

So if you’re wondering who jinxed 2008 for us, it’s this man. Zonk, it’s like I don’t even know who you are anymore! Come back to us!