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Summer in Limerick

As some of you may know, I am currently in Ireland, spending most of the summer at the Irish Software Engineering Research Centre to get a start on my Ph.D. research. This is the story of how I got here and how it's been so far.

In the middle of July, I left my beloved city of Zurich and headed for Dublin. I commenced my stay in "the green country" with a three-day Debian workshop for the Google Europe sysops, which was intensive and yet enjoyable. I had between 4 and 10 participants, and the syllabus was to cover most everything, from APT basics to advanced concepts. That's a lot for three days, and I usually advise clients to consider a five-day or even two-week course instead, but after convincing the organiser to plan for three days rather than just two, I figured I'd be dealing with pretty good people anyway, given Google's hiring standards. I was not to be disappointed.

We started the course with installation problems, because the 2.6 kernel install which I suggested could not deal with the SATA driver in the new IBM T43p notebooks which the participants were using. While one guy decided to try a 2.4 install with the IDE-sata driver, I opted to go down the debootstrap route instead, and was especially delighted -- at first -- to learn about a working netboot setup in the Google LAN. My joy vanished when I found the Ubuntu rescue image not to contain debootstrap, so I didn't have much choice but to prepare a root tarball and offer it for wget download. This worked, and after manual tweaking and making the system bootable, running into some issues after inadvertedly upgrading the entire system to the backports.org archive (which still does not offer a proper default pin), we decided to just go with testing and be done with it.

I have to say that I really like courses where stuff does not work, as I believe those to be far more valuable to the participants. This time around, it was also the first time (after having taught maybe 60 or 70 courses in total) that I did not let myself get stressed out. Realising this put me in a great mood and made those days even more enjoyable.

The rest of the workshop went without further complications, but judging from feedback over cigarettes, lunch, or the evening beer(s), the guys and girls still appreciated it. I have to thank Google and all participants for a great three days of hospitality and challenges, interesting discussions and fun. I really ought to reconsider my decision not to accept their offer for a sysop position...

The last day saw me getting sick though, it must have been the air-conditioning. When I reached the hotel after the course, I definitely knew I had high fever and was developing a bad headache and cough, so I didn't get to enjoy a Friday night out in Dublin. Instead, I slept from 18:00 hours until the late morning, when I had to drag myself to the train station to catch the train to Limerick... which was painful, but I managed. Some time in between, I tried out nstx and managed to get a decent SSH connection to the outside world from the hotel room (just don't forget the -a -x flags!).

Arriving in Limerick, I registered for the student apartment I had rented and found myself in a small room with a bed and desk, my own bathroom, a common room and kitchen I share with my room mate (whom I barely saw), including a TV, fridge, oven, microwave, and enough "little stuff" to make me conclude that this place was livable -- for 60€/week not a bad deal. I spent most of the weekend sleeping, but it was not until Tuesday that my state had returned to normal.

The place also has an Ethernet jack, but that turned out to be unusable as it was (a) behind a fascist firewall, and (b) on the same network as about 40 other users, 17 of which seemed to be running peer-to-peer filesharing clients all hours of the day. In my office at the university, I found myself in the same situation as (a), but at least I managed to install OpenVPN, and dsniff and was thus ready to take back the net in my apartment. I wrote a little script which would (a) spoof ARP replies from the router for all hosts for a few minutes, (b) analyse the traffic it got to identify obvious P2P machines, and (c) proceed to poison their ARP cache every few seconds, effectively shaping their connection. I had to go this way, because tools like tcpnice (part of dsniff) do not work in a switched network very well, and neither did macof. Unfortunately, I lost the script in the recent XFS fiasco, but the major P2P offenders seem to have left anyway.

Thanks to OpenVPN, I also got VoIP working and am happily tunneling through the university's proxy (which otherwise would require me to use the SOCKS4 proxy protocol with proxychains, which would be a nuisance). I really don't understand why a university blocks outgoing traffic. Oh well...

It's been three weeks since I've come to Limerick, and my feelings are mixed. I've been spending most time in my (temporary) office (pretending to be) doing work, I have not really acquainted myself with the food here, the university campus is filled with hundreds of 14 year old summer school students but nobody of my age, and, well, research is coming along slower than I had hoped. I guess that's normal in a sense, but I also know for sure that I have a lot of work left to do on my discipline. I am a master of procrastination, you see, and Debian is a dangerous drug, a black hole that sucks in your time while it excites your synapses and splashes endorphines all around. But I've not lost my hope at the very least...

Thanks for caring.