After 6 weeks of teaching and over 2 months in my new apartment, I am making a short escape from NYC to visit my mom and sister in PR. In my Impacts of Technology class, we just finished a week on large-scale and complex technological systems, with a focus on industrial farming. We read a few sections of Micahel Pollan’s fanstastic book, The Ominvore’s Dilemma, which combines the odd qualities of being seductively alluring (thanks to his exquisite writing) and repulsive (thanks to the content, well at least the part on factory animal “farming”). I can’t recommend it enough and look forward to reading the rest, when I find the (magical) time to do so. Now that I am at the airport, I am struck at how little I know about this place, which is also a large and complex technological system and I bet revealing its technological and cultural innards would provide as fascinating (although not quite as gross) of a story as that of factory animal farming. There are many questions I would love answered: How exactly is coordination secured and what are the toughest elements to airport coordination? Where are the lines of cooperation and those of competition between airlines? What factors and values go into the design of the airport? (I know that for one thing, in American airports, there rarely seems to be enough electrical jacks; I am now sitting under the telephones, the only place with jacks in terminal 8 at JFK, and the funny thing is that there are a row of 7 unused phones and only one jack and I am sure it would be more useful to have 1 pay phone and a row of 7 jacks, instead). What sorts of airport technologies have put people out of jobs? What technologies have created new job opportunities? What sorts of social hierarchies are there in airports? Like who runs the big show? Is it a CEO? Or is something more like a university provost? What is standardized by the FAA, and what elements are more flexible, and thus different airport to airport? Is there a sense of camaraderie among airport employees, or are loyalties built primarily among employees of one airline or among the classes of workers? Given that unions are quite strong among airport employees and from the top (pilots) down (food workers), what is the political culture of airports/employees like? (I remember once overhearing a group of machinist and ground crew talking about the ugly face of globalization and NAFTA over coffee and I was dumbfounded and pretty psyched too). Are airports one of the few last remaining places in th US that provides for decent job security? Why do so many of the ground crew have such athletic, bulging calves? Is it a result of the physical demands of the job? Or is it that the type of job ( outdoors with lots of heavy lifting), attract the athletic types? Do they have to pass certain physical standards as to pilots? Was there always first class seats? Or did that come about when flying became cheaper? Are employees trained to deal with irate passengers? In what ways do pilots bitch about the long waits/delays they also have to endure? What can they do when they are waiting, as we did for an hour last night, during the massive traffic jams that are especially noxious in NYC-area airports? Do pilots have any say in the way airports are run? Why do they consistently provide less chairs than are needed in lounges, even in new terminals, as the one I was in tonight? Do air traffic controllers ever meet face-to-face with pilots or do they largely have a virtual relationship? Are programmers who patch, improve, and build traffic control systems housed in the airports, or elsewhere? Airports are not only fascinating for technological and sociological reasons but I reckon there is a lot of interesting psychological work that must happen in airports. I imagine that during those long, endless waits in the lounge, on the security lines, on the tarmac, people must often take the time to reflect, on where am I going, where am I coming from, and not in the literal sense but the metaphorical one. I know that I have spent many hours in airports letting my mind wander to places and thoughts in ways that don’t happen as easily or often elsewhere. And in many instances, I don’t think that this propensity to indulge in some reflective thinking, is a matter of time, that is waiting. For me at least, it is the fact that many times when I fly, I am moving between worlds. While I have flown hundreds of times, I never have been shed of the sense of awe I feel about planes and their ability to shrink space and time so quickly. For me, it is less the act of flying itself (that feels boring, tiring, annoying, mostly because of the insane waits and delays and I never seem to get the right amount of sleep the night before) but the visceral contrast it brings. In the morning my life is of a particular tone and rhythm, currently situated in NYC and by evening, I am back at home in PR, surrounded by thick humidity and the loud sound of coquis. Once there, my as currently configured in NYC, has little direct bearing to those around me. Planes don’t just transport, they shift and convert your inner and outer world… So, if anyone (who got this far) knows of a good social history of the airport, do tell. I would love to read it.

This weekend, I m attending the Haskell Hackathon in Freiburg. Regular readers of my blog will have noticed an increasing interest in Haskell, so having this event so close was a nice chance to get more involved in the Haskell community. My blog also got added to Planet Haskell now.So far, I have hacked up a simple haskell program called Haskell Package Version Tracker . It takes the 00-index.tar.gz file of hackage (which is for Haskell what CPAN is for Perl) and a Debian Source file (which is the list of available packages in Debian) and outputs a comparision in the spirit of the Debian Perl Group s or utnubu s version comparison pages. You can see the last output, but I do not yet update that page regulary. The code is available in a Darcs repository. It uses the Index.hs-File from hackports thaks for that.

There is ongoing debate about the issue of security cameras, how many should there be, where should they be located, and who should be able to access the data. I spent about a year living in London which probably has more security cameras and a greater ratio of cameras to people than any other city. I was never bothered by this. I believe that if implemented correctly security cameras increase public safety and will not have any serious problems. A while ago I witnessed a violent assault (which could potentially have ended up as a manslaughter case - it was merely luck that ~200 people got off a train at the right time to scare the attackers off). AFAIK I was the only person who identified themself to the police and was prepared to stand as a witness, without security camera footage the case would not have gone anywhere (I only saw the attackers from behind as they ran off). Security camera footage allowed the police to identify the attackers, my testimony was not required and I was never informed as to how the case proceeded - but I know for a fact that the police investigation depended on security camera footage and that they did make progress in the case based on such footage. There are current plans to increase the scope of security cameras in many cities under the guise of the “war on terror”. The problem is that once a terrorist is involved in an attack it’s too late for security cameras. Security cameras are really only good for catching criminals after an attack, in most cases they will be entirely ineffective against suicide bombers as the issue of catching them is moot. There have been cases where security cameras have enabled the authorities to identify people with terrorist ideas who were investigating military bases (but I wouldn’t call such lamers “terrorists” as all the available evidence suggests that they would be incapable of succeeding in an attack). However no-one is disputing the fact that military installations need to have good security. Given that security cameras do provide significant benefits to public safety I don’t think it’s reasonable to oppose them as long as they are implemented in a sensible and responsible manner. Most of the current plans to install security cameras don’t seem to be sensible and have few controls on who can access the data. This makes them good targets for oppressive government actions, organised crime, and even terrorists. The countries that have serious terrorist problems always have problems of terrorists infiltrating government departments and bribing government officials. A centralised system that allows the police to watch anyone at any time would probably do more good for al Quaeda and the Mafia than it would for regular police action. For the fastest possible response a security camera system needs to have humans able to monitor it’s output in real-time. Having a control-room where police officers can randomly switch between public cameras to see if a crime appears to be in progress is a good thing (and works well in the UK). Of course the actions of such police need to be monitored to make sure that they are actually doing their job (not checking out hotties on the camera - an ongoing problem with security cameras). Finally there’s the issue of what level of surveillance can be expected in a public place. I think that most people agree that when you enter a government building it’s reasonable to expect that you will be on camera, and many private buildings have security cameras with a condition of entry being that you permit yourself to be watched and no-one seems to be boycotting shopping centres because of this. Significant public spaces such as main roads and public transport also seem like reasonable locations for security cameras. One location that is widely disputed is that of streets in residential areas. Most people who are happy to be photographed when entering and leaving public buildings such as train stations and shopping centres are not happy to be photographed when entering and leaving their own home. I think that a reasonable solution to these problems requires the following:

1. Restrictions on the duration and scope of surveillance in residential areas (EG require police to get court orders for such surveillance that must be periodically renewed).


2. Restricting the duration for which records may be kept by the police. Keeping any records for longer than the period in question (which would be a few weeks at most) would require a court order.


3. Prohibiting private organisations from handling surveillance data from government property (including public roads, train stations, etc). There are problems with having a private company aggregate surveillance data from multiple private properties but I don’t think we can address this at the moment.

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The following companies, or people, are using xen-shell with their Xen hosting product(s):

• xen kibbutz
• xen hosting (me!)
• bit folk
• Datarealm internet services
• Chris Lamb
• Cernio

I'm sure there are more, but I've been lax at keeping track. I do want a list, if only for advertising purposes. I'll update the list here if/when people point out omissions. In other news yesterday I managed to release security updates for KDM & fetchmail which were missing i386 builds. Not good. The problem was fixed fairly quickly once it was actually noticed, with the help of Noah. But I did get several angry emails during the wait. *sigh* It looks like people are starting the notice the downside to having broken security buildd machines which frequently cause these kind of problems for us - so hopefully these kind of errors will diminish in time. (Who am I kidding?)

As I have been such a good girl recently, I deserved some prize. I’ve always been in love with tiny light lappys, so I got myself one from ebay. It’s a 10″ 800 MHz Sony Vaio that weights slightly above 1 Kg, which means that I’d be able to carry it to anywhere I want. Debian has installed smoothly on it, even though I’ve had some problems due to the lack of CD/DVD and floppy drives, and my inability to make Debian Installer start from an USB pen. Most of it seems to be working properly right now, only small configuration issues are still pending. I’m really happy

Via Anomaly Television: The video "This Fortean Island" is a seemingly random mixture of "cultism, death, UFOs, Bohemian Grove, Illuminati, Skull & Bones, Freemasonry, and necrophilia", with Discordianism being the connecting element. You can watch it on Google Video or get it as an AVI.

I’ve recently spent some time on Facebook, primarily out of professional interest (all the cool attorneys are doing it). (I’m also on LinkedIn, but that seems less cool.) Among other odd results, I’ve been getting lots of friend requests from people I’ve had no contact with in ten — and sometimes twenty or more — years. I’m surprised by this because I’ve always been so easy to find. I started my first “home page” in 1994, and as long as the idea of search engine rankings has existed, I’ve been at the top in searches for my name. I’ve also never made any attempt to hide my email address, and retained all addresses for nearly 15 years. Yet, people contact me on Facebook who never before did. I have two nonexclusive theories:

• Facebook just induces more searching for old friends than “the web at large.”
• Facebook allows you to reconnect with people for a minimum activation energy. You don’t have to write them an email, tell them about your life, or engage in conversation. You just click “add to friends” and you’re done. Maybe these people had found me in the past but just didn’t bother to let me know. In fact, in the case of some of these people with whom I haven’t communicated since middle school, I still haven’t communicated with them. We’re just Facebook friends.

Other ideas? I should add that I have made some genuine connections through Facebook as well. Earlier this week, I met a college friend (whose website promises to return to service soon) for dinner whom I hadn’t seen in nearly ten years. I found out he was in town through Facebook.

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Thanks to Faidon Liambotis, pristine-tar has been extended to support recreating pristine gz files, as well as tar files. It's been tested against the entire corpus of .tar.gz files in the debian archive, and succeeds on 98.7% of them. We're using the whole archive as a test suite for pristine-tar, which is such a nice change -- excellent test coverange, and no need to write tests. :-) I've put up all the deltas it generated during its most recent run at http://hydra.kitenet.net/~joey/tmp/tar/. The deltas for all the tarballs in the archive use only 175 mb of space. The next step, once it gets out of incoming will be for tools that inject sources into revision control to get support for generating pristine-tar deltas and checking the deltas in too. And for tools that build packages from revision control to get support for using the deltas to reproduce the original tarball. If you maintain such a tool, I'm happy to help you do that. how pristine-gz works Recreating gz files is tricky, since you generally can't binary diff them as pristine-tar does with tar files. Instead, gzip has to be fed exactly the same conditions that applied when the original gz file was created. This includes time stamps, filenames, file content, and compression level. These are figured out by looking at the header of the gz file. But that's only the easy part, because there's a lot of variation in gz creation programs. The debian archive contains gz files produced on BSD systems by a libz based compressor, other built on MS-DOS, Windows NT, and many other strange and often buggy things. All of these differences result in different gz files. To deal with this, pristine-gz uses a gz creator that can reproduce any of the known variants on demand, and just tries different varients until it finds a match. There are still 132 files that it fails to reproduce, so if this sounds interesting to you, you can try to figure out how they were created and add support for them. It would be possible to make pristine-gz succeed even for gz files it can't reproduce. It could just generate xdeltas to the files it tries, and store the smallest one. I am undecided if that would be a good idea, since the delta wouldn't be very small.

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Some days ago I started using knode and becoming familiar with nntp.

Since ispCP's lists are hosted at Google Groups I just wanted to subscribe to all the newsgroups using knode. But what a shame... I can only subscribe to Google Groups either by email or by RSS/Atom Feeds :(

At the time of writting I'm filling up the "Subscribe A Mailing List" form at gmane.org.

I actually tough Google would not fall on that 'only from http' tradition it has... but, it indeed did.

We have an additional listmaster@teams.debian.net: Michael Banck. Thanks for joining the team. No Tags

There seems to be a recent trend towards home-schooling. The failures of the default school system in most countries are quite apparent and the violence alone is enough of a reason to keep children away from high-schools, even without the education (or lack therof). I have previously written about University degrees and whether they are needed [1]. The university I attended (which I won’t name in this context) did an OK job of teaching students. The main thing that struck me was that you would learn as much as you wished at university. It was possible to get really good marks without learning much (I have seen that demonstrated many times) or learn lots of interesting things while getting marks that are OK (which is what I did). So I have been considering whether it’s possible to learn as much as you would learn at university without attending one, and if so how to go about it. Here are the ways I learned useful things at university:

1. I spent a lot of time reading man pages and playing with the various Unix systems in the computer labs. It turned out that sys-admin work was one of my areas of interest (not really surprising given my history of running Fidonet BBS systems). It was unfortunate that my university (like almost all other universities) had no course on system-administration and therefore I was not able to get a sys-admin job until several years after graduating.

I read lots of good text books (university libraries are well stocked).

There were some good lectures that covered interesting material that I would not have otherwise learned (there were also some awful lectures that I could have missed - like the one which briefly covered computer security and mentioned NOTHING other than covert channels - probably the least useful thing that they could cover).

I used to hang out with the staff who were both intelligent and friendly (of which there were unfortunately a small number). If I noticed some students hanging out in the office of one of the staff in question I would join them. Then we would have group discussions about many topics (most of which were related to computers and some of which were related to the subjects that we were taking), this would continue until the staff member decided that he had some work to do and kicked us out. Hanging out with smart students was also good.

I did part-time work teaching at university. Teaching a class forces you to learn more about the subject than is needed to basically complete an assignment. This isn’t something that most people can do.

I expect that Children who don’t attend high-school will have more difficulty in getting admitted to a university (the entrance process is designed for the results of high-school). Also if you are going to avoid the public education system then it seems useful to try and avoid it for all education instead of just the worst part. Even for people who weren’t home-schooled I think that there are still potential benefits in some sort of home-university system. Now a home-university system would not be anything like an Open University. One example of an Open University is Open Universities Australia [2], another is the UK Open University [3]. These are both merely correspondence systems for a regular university degree. So it gives a university degree without the benefit of hanging out with smart people. While they do give some good opportunities for people who can only study part-time, in general I don’t think that they are a good thing (although I have to note that there are some really good documentaries on BBC that came from Open University). Now I am wondering how people could gain the same benefits without attending university. Here are my ideas of how the four main benefits that I believe are derived from university can be achieved without one (for a Computer Science degreee anyway):

1. Computers are cheap, every OS that you would ever want to use (Linux, BSD, HURD, OpenSolaris, Minix, etc) is free. It is quite easy to install a selection of OSs with full source code and manuals and learn as much about them as you desire.

University libraries tend not to require student ID to enter the building. While you can’t borrow books unless you are a student or staff member it is quite easy to walk in and read a book. It may be possible to arrange an inter-library loan of a book that interests you via your local library. Also if a friend is a university student then they can borrow books from the university library and lend them to you.

There are videos of many great lectures available on the net. A recent resource that has been added is Youtube lectures from the University of California Berkely [4] (I haven’t viewed any of the lectures yet but I expect them to be of better than average quality). Some other sources for video lectures are Talks At Google [5] and TED - Ideas Worth Spreading [6].

To provide the benefits of hanging out with smart people you would have to form your own group. Maybe a group of people from a LUG could meet regularly (EG twice a week or more) to discuss computers etc. Of course it would require that the members of such a group have a lot more drive and ambition than is typical of university students. Such a group could invite experts to give lectures for their members. I would be very interested in giving a talk about SE Linux (or anything else that I work on) to such a group of people who are in a convenient location.

The benefits of teaching others can be obtained by giving presentations at LUG meetings and other forums. Also if a group was formed as suggested in my previous point then at every meeting one or more members could give a presentation on something interesting that they had recently learned.

The end result of such a process should be learning more than you would typically learn at university while having more flexible hours (whatever you can convince a group of like-minded people to agree to for the meetings) that will interfere less with full-time employment (if you want to work while studying). In Australia university degrees don’t seem to be highly regarded so convincing a potential employer that your home-university learning is better than a degree should not be that difficult. If you do this and it works out then please write a blog post about it and link to this post.

• [1] http://etbe.coker.com.au/2007/01/24/university-degrees/


• [2] https://www.open.edu.au/wps/portal


• [3] http://www.open.ac.uk/


• [4] http://youtube.com/ucberkeley


• [5] http://www.youtube.com/user/AtGoogleTalks


• [6] http://www.ted.com/

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I got a call from one of the researchers from ABC news this evening. Apparently they are planning on doing a segment on Hans Reiser on their 20/20 show, and the researcher knew enough that there were some serious technical inaccuracies with the script (at the level of “so when Hans was creating reiser4, was that software; was he writing a program?” and “does the program run on the hard drive?”), and so they were looking for help on some technical issues on a background basis. She didn’t take any quotes from me; what she needed was help understanding the technical issues around filesystems and Linux. I tried to help explain what a filesystem was that would make sense to a lay person in 15 seconds; I have no idea whether the researcher got it, and whether she’ll be able to make changes in the script that will be vaguely coherent. We’ll see. I spent a lot of time working with Joshua Davis, providing background material for his Wired article, and he still got a bunch of the technical details wrong. The 20/20 researcher did ask me some silly questions such as “whether we were surprised when murder charges were filed against Hans?” Well, yes. What did she expect me to say? “Oh, yes, were always worried someone would get hurt…” Not! Sigh…. I might not agree with Hans’s filesystem design principles or his tactics in trying to get reiser4 accepted, but I always respected him as a fellow open source programmer. The researcher mentioned to me that Hans had done a talk at Google that was available at the Google Video site. Out of curiosity, I took a look at it. It was interesting; the last time I had seen Hans was in 1999, at the Linux Storage Management Workshop in Darmstadt, Germany that was organized by Matthew O’Keefe at Sistina Software. Compared to how he looked back then, and the picture of him in the Wired article, taken a 10-12 months after his talk at Google in February, 2006, I was struck by how much heavier (and older at least compared to my memory of him, which was much closer to this picture from his resume) in the Google Video. I also remember him as being a much more dynamic and energetic speaker, and I was struck by how slowly he spoke, with lots of long pauses and “umms” and “ahhs”. He seemed to be a much better public speaker in Darmstadt, but in the Google talk he seemed very tired as he gave the talk. One of the questions that the researcher asked me was whether I thought he was a genius or not. I told her that I thought he was quite bright in terms of raw intelligence, but that his Social IQ wasn’t as high as you might want for someone to be successful in gathering volunteers to work on an Open Source project, and in working with others in an Open Source development community. Looking at the video, I think that is very much true. He was a terrible public speaker, but some of the points he made about optimizing B-tree algorithms made sense. I might disagree with his philosophy over filesystem design and benchmarking, and I might not be terribly impressed by his social skills, but in terms of being a talented computer scientist, he was and is that. Is he guilty of the crime that he has been accused of? I have no idea. But from looking at his talk and knowing what I know of him, I have the sense of a greek tragedy. He’s been working on some of his ideas since his undergraduate days in UC Berkely in the early eighties — which he entered after finishing his 8th grade. And as research ideas, I think he might have gotten some very interesting results out of trying some of the things that he wants to do around operating system namespaces. (I think they are doomed in a production system descended from Unix, since application programmers are unlikely to rewrite their programs to take advantage of reiserfs’s performance characteristics — which would mean instead of using a Unix-like configuration file, treating a directory hierarchy containing the configuration information like a Windows registry. Still, as an academic, Plan 9-like system, I could have seen it has being a potentially very interesting Systems Research effort.) Unfortunately, his skills at public speaking and his ability to work with other people have handicapped him, and I know that has frustrated him deeply. So I have a lot of sympathy for him, and I hope that he is innocent, and will be found innocent. But only time will tell…. Anyway, according to the researcher, they are currently scheduling their segment about Hans on 20/20 on October 19th. I’m sure that schedule is subject to change, but it’ll be interesting to see how they treat Hans in their coverage. Hopefully it will be fair, and not overly sensationalistic, but unfortunately my faith in today’s TV edutainment-focused news program isn’t terribly high. My impression was that the research wanted to do a good job, but she was burdened by a very tight deadline, and in the end, the decision of what goes on the air and what doesn’t won’t be up to her. So we’ll see.

Although I predicted that I'd be a busy boy with my bushfire brigade on Tuesday, I wasn't expecting to get our first "Bush Alight" fire call so quickly. But, yesterday (Wednesday), a few minutes after 1800, off goes the pager, and off I go to the station. Thankfully the high winds that had been a major feature of the day had settled down quite a bit, so it was relatively easy to control and stamp out (we were back at the station by around 2015) I still found it a little overwhelming -- "I'm supposed to help Stop This Fire". At a couple of hectares in size, it wasn't too massive, and it wasn't visually "spectacular" (like the fires you always see on the news) but still... given that my only experience of fire in the past has been small campfires and the occasional bonfire, having an area the size of a football field in front of you glowing with embers and flaring with small clusters of flames, it was certainly a very different experience. The heat, the smoke, the noise (those truck pumps are loud), and the adrenalin, it's a hell of a mix. Being that I'm the newest and least experienced crew there, I got given the unglamourous but important job of controlling traffic, as we had one lane of the one-each-way 100km/h road closed to give our crews more working space around the trucks. Let me just say that I now have an infinitely greater respect for road repair crews, and I think that every person should do an evening of traffic control with a group of their mates on the road behind them, so that they know what it feels like outside their car. Car drivers do the darnedest things. So, I've popped my bushfire-fighting cherry now, and I'd be more than happy if there's nothing more impressive than that awaiting me for the rest of the season.

This Monday, state secretary Bijlevelt of interior affairs finally decided that any current type of voting computer is not safe enough for elections. This decision is not a surprise for anyone who's followed along with the wedonttrustvotingcomputers.nl action group, but it's the first time the government has acknowledged the full problem. This means that on the next "election" at October 10th here in Utrecht, already the red pencils will be recovered from their long time storage. Most interesting about this whole discussion is the question I only see asked sparingly:

What problem are voting computers trying to solve?

As a data point: on the last general elections, the Amsterdam district finished their counts of pen-and-paper voting before midnight on election day.

I got a little older yesterday. I'm 26 now. It was a fun day. It started out by going to the Federal Police to get my temporary id. The agents who register foreigners are on strike for the last week or so, but there was someone there dealing with the registration. So my name got put in a big book and I've got a piece of paper that will let me back into the country next week.

Now for the actual birthday. A bunch of use went out to a place called Pinguin (yes, Penguin in Portuguese). We had some chopp, some very good garlic bread. Then since it was my birthday we got a cotton candy cake, and a nice little Penguin!

Sarah had been complaining that MythTV hadn't recorded an episode of The Simpsons in months. It was indeed strange, as you could see that it was going to record episodes if you looked at the upcoming recordings. The other night we happened to be watching some recorded TV around the time an episode was scheduled to be recorded, and sure enough, it started recording one. When we finished watching what we were watching, the episode had vanished. I didn't think I'd seen anything relevant to auto-expiry in the logs for the backend. A few days later, another episode was recorded. We even watched it. It disappeared afterwards. I was sufficiently curious at this point as to what was going on. It turned out that way back in the distant past when I set up MythTV, I misunderstood what "recording groups" were. When I set up recordings of throw-away things like the news, I created a recording group called "Short retention", assuming I could go somewhere else and make stuff in that group get expired quicker than stuff in the "Default" recording group. (Incidentally, I only in the last few months discovered the veritable cornucopia of things that you can do from the recordings listing screen when you press the Menu/M button on the remote/keyboard. The recording groups now make much more sense) I think there's the word "storage" somewhere in the user-interface around this area, which may have been what confused me. Turns out that I never went and tried to set this mythical expiry policy up, because that's not how auto-expiry works. The choices (as of 0.20) are "Oldest show first", "Lowest priority first" and some sort of weighted combination of the two. It turns out that I had it configured for "Lowest priority first", and The Simpsons had the lowest priority of all TV shows, so that it'd always lose out in the event of any scheduling conflicts. The SAN's perpetually full, so it's always auto-expiring stuff, and The Simpsons are what get expired first by this policy. Kinda funny really. So I switched the policy around to the weight combination of priority and age, and now it's going to auto-expire recordings from a year ago. Hooray.

Today I received the replacement hard drives for the two that failed the other week. Despite me not ticking the box (or paying the $10 for the upgrade), they gave me 500Gb drives to replace the 400Gb drives that I'd shipped them. I was a little dismayed to find that they were labelled as refurbished drives though. Oh well. I plugged the first drive in, and it started exhibiting the same behaviour as the one that had failed, and I immediately thought "oh, they've shipped me a dud refurbished drive". So I tried the other one. It also did the same thing. I started to smell a rat. I have a slightly convoluted power setup for these four disks. They're all connected to minotaur via IDE-USB adapters, and they have external DC power supplies. They're just sitting on top of minotaur, which is a Pentium III 1-RU server, in the bottom of my linen cupboard. In order to reduce the number of plugs involved, I have an IEC Y-cable, which goes to two of these DC power supplies (which take an IEC cable in one end and has a Molex connector on the other end), and the Molex cable from the DC power supply has a Molex splitter cable on it. So I'm powering two drives from each DC power supply, and each DC power supply is connected to an IEC Y-cable. There's no redundancy whatsoever, and I'm not that concerned. I don't have a UPS anyway, and the whole thing has worked fine for months, and it reduces the rats nest of cables a little bit, which is good. I already have way too many things plugged into my linen cupboard. Anyway, so after both new drives appeared to be faulty, I discovered that both drives that had failed within a day of each other were connected to the same DC power supply. The plot thickened. So I dug out a standalone IDE-USB hard drive enclosure (with a separate power supply) and tried that. Everything worked. I tried it with just the enclosure's power supply and either of the IDE-USB adapters I'd been using previously. Everything worked. So I'd managed to narrow it down to the power supply. Most unusual. So fortunately I have four of these DC power supplies, as they came with the IDE-USB adapters, and I freed up two of them when I went for the aforementioned crazy power splitting setup, so I dug out one of the two spares, and tried that, and everything worked. So I've no idea why the power supply decided to go dicky after months of working. I've yet to introduce my multimeter to it to try and work out what's going on. I'm a bit embarrassed that I didn't do more homework before I declared the drives to be faulty. To be honest, they were clicking and generally looking "failed", and I've had a lot going on lately, so I just jumped to the conclusion. Oh well, at least I still haven't lost any data. Too bad I have 200 Gb that is going to go to waste.

This evening I renamed a number of UWCS’s mailing lists for a few reasons, mostly due to the annoying ambiguity of the old names. Mailman doesn’t make this particularly easy - this how you can do it under Etch;

1. First, define variables to avoid stupid mistakes:

   $ OLD=old-list-name
   $ NEW=new-list-name
   $ set -u

2. Next, take down Mailman and do a quick sanity check. The MTA should queue any incoming mails when qrunner stops responding.

   $ sudo /etc/init.d/mailman
   $ sudo sh -c "[[ -a /var/lib/mailman/archives/private/$ NEW  ]] && echo '*** That mailing list name already exists. *** '"

3. Now move the list data and regenerate the archives for that list:

   $ sudo mv /var/lib/mailman/lists/$ OLD  /var/lib/mailman/lists/$ NEW 
   $ sudo mv /var/lib/mailman/archives/private/$ OLD  /var/lib/mailman/archives/private/$ NEW 
   $ sudo mv /var/lib/mailman/archives/private/$ OLD .mbox /var/lib/mailman/archives/private/$ NEW .mbox
   $ sudo mv /var/lib/mailman/archives/private/$ NEW .mbox/$ OLD .mbox /var/lib/mailman/archives/private/$ NEW .mbox/$ NEW .mbox
   $ sudo /var/lib/mailman/bin/arch $ NEW 

4. You should probably provide legacy aliases:

   $ cp /etc/aliases  mktemp aliases-backup.XXXX 
   $ printf "\n# '$ OLD ' -> '$ NEW ' mailing list rename \n"   sudo tee --append /etc/aliases
   $ echo "$ OLD : $ NEW "   sudo tee --append /etc/aliases
   $ for SUFFIX in admin bounces confirm join leave owner request subscribe unsubscribe; do echo "$ OLD -$ SUFFIX : $ NEW -$ SUFFIX "   sudo tee --append /etc/aliases; done

5. Now go to the administrator interface and change:
   • General / real_name: NEW
   • General / subject_prefix: “[NEW] ” (or similar)
   • Privacy / Recipient filters / acceptable_aliases: Add OLD
6. Now, bring everything back online with:

   $ sudo newaliases
   $ sudo /var/lib/mailman/bin/genaliases
   $ sudo /etc/init.d/mailman start

7. For bonus points, generate yourself Apache redirect for the new name:

   $ echo "RewriteRule ^/([^/]*)/$ OLD ($ (/.*)) /$1/$ NEW $2$3 [R=301,L]"

Ta-da, nice new names. You will need to warn your users as their filtering will have now broken.

Is it possible, under Linux, to request a Kerberos ticket-granting ticket from one Kerberos realm without destroying your TGTs from another realm that are already in your credentials cache? Otherwise, this happens:

Ticket cache: FILE:/tmp/krb5cc_2000_O5THYS
Default principal: wouter@EXAMPLE.COM
Valid starting     Expires            Service principal
10/02/07 19:29:53  10/03/07 05:29:53  krbtgt/EXAMPLE.COM@EXAMPLE.COM
	renew until 10/03/07 19:29:50
10/02/07 19:29:56  10/03/07 05:29:53  HTTP/exampleserver.example.com@
	renew until 10/03/07 19:29:50
10/02/07 20:52:54  10/03/07 05:29:53  host/exampleserver.example.com@
	renew until 10/03/07 19:29:50
Kerberos 4 ticket cache: /tmp/tkt2000
klist: You have no tickets cached
wouter@country:~$ kinit wouter@GREP.BE
Password for wouter@GREP.BE: 
wouter@country:~$ klist
Ticket cache: FILE:/tmp/krb5cc_2000_O5THYS
Default principal: wouter@GREP.BE
Valid starting     Expires            Service principal
10/02/07 20:59:01  10/03/07 06:59:01  krbtgt/GREP.BE@GREP.BE
	renew until 10/03/07 20:58:57
Kerberos 4 ticket cache: /tmp/tkt2000
klist: You have no tickets cached

Note the complete absense of any reference to the first realm in the second klist output, which is annoying. (Yes, I do know about the possibility to create trust paths between two realms; But I'm not going to give customers access to my personal mailserver...)