It seems like VServer is not something for long run because it does not seem to want to be upstream and there is also no good future for having it as patch in Debian for long run. So I should look for alternatives and probably migrate to some other solution while upgrading my server to Squeeze (once it is released or really close to the release). There are various options, starting with OpenVZ, through Linux Containers (LXC) up to full virtualization (probably KVM based). With OpenVZ the situation won't be much better, so it is not a real option. For various reasons I don't want to go to full virtualization, I simply thing containers are good enough and avoid too much overhead in some situations. So the only remaining solution seems to be LXC. There even seem to be some people who managed to migrate from VServer, which is good and will be definitely helpful. Now it's time to play with lxc a bit before I will try to implement it for real.

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On the 13/14 November 2010 there is a nice event in the so called Ruhrpott : OpenRheinRuhr. And I d like to invite YOU :)What should you expect from heading to the RIM in Oberhausen and paying 5 entry-fee? You get a nice program full of great talks (like mine about bley ;), mikas about OpenSource management, tokkees about Git and XTarans about cli-helpers and unknown tools), a bunch of nice people showing you their distro, software, etc (Debian is there too), a social event, a keysigning party and a lot of hacking and fun. So if you are somewhere nearby, join us and enjoy the event!

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German version (sorry planet debian readers ;)):Am 13/14 November findet im Pott die OpenRheinRuhr statt, zu der ich euch alle herzlichst einladen moechte.Was kann man erwarten, wenn man den Weg ins RIM in Oberhausen gefunden hat und die 5 Eintritt bezahlt hat? Euch erwartet ein Programm voller Talks (zB meiner ueber bley ;), mikas ueber OpenSource Management, tokkees ueber Git und XTarans ueber Helfer auf der Kommandozeile and anderere unbekannte Tools), viele Aussteller, die die eigene Distro, Software oder was auch immer anpreisen (Debian ist natuerlich auch da), ein Social Event, eine Keysigning Party und natuerlich viel Rumgehacke und Spass. Also, jeder der grad irgendwie in der Naehe ist oder in die Naehe kommen kann: ab nach Oberhausen und geniesst ein freies Wochenende! :)

*blows the dust off his blog*

It's been quite awhile since I last wrote anything in this thing, so I guess its a good time as any, off the tails of UDS-N, to finally sit down and write something down. Since my last blog posting in May, I've been travelling around the world, attending conferences, and trying to represent both Ubuntu and Debian itself, and Canonical in all my travels. I was recently posted to China for a full month where I lived and worked out of an office, made friends with fellow Ubuntu users, and tech enthusiasts, had a wonderful time meeting with people with the Beijing Linux User's Group, and worked hard within my team at Canonical, and the legions of Ubuntu Developers to help make one of the best releases we've ever had.

As I was writing specs and drafting work items, I came to the point that I was reflecting on my own personal goals and growth in life. Two years and change ago, I was a struggling junior at Rochester Institute of Technology, a little less than two years ago, I started working full time with Canonical, and this year, I've gone and traveled to many places I've only dreamed about; Anchorage & Barrow, Alaska; Tampere, Finland; Prague, Czech Republic; and Brussels, Belgium, just to name a few. I packed up and lived in China for a month (an amazing experience, and I look forward to going back and visiting again sometime in the near future). Had you told the me of two years ago what I would be doing now, I'd probably think you were smoking something good.

One thing I've discovered in my life is that if you want to do something, you need to get out there and just ****ing do it. This may seem simple, but I think of the dreams a lot of people have that never seem to come to fruition. When I have an opportunity, I take it; going to Alaska was a dream I harbored for many years, especially entering the arctic circle, and heading to Barrow. That entire trip was booked on roughly four days notice, and the side trip to Barrow was planned the day before it actually happen. I don't regret any of it; it was one of the best things I ever done.

It brings me to what I consider the flux of this blog posting. For those who know me, I've had a goal of visiting every state within the United States. At this time last year, this map looked like this

As of two weeks ago today, this map looked like this:



Now, by the end of the day today, it will look like this:



The point I'm trying to make is if you want to do something, do it the first chance you get, or just don't do it; I say this because you never know when you will be able to do it again.

As for completing a life goal, well, it feels pretty amazing :-). I may write about that in a future blog posting ...

I miss the days when Debian was about making software work well together. These days the user mailing lists are full of posts from users asking for help on Ubuntu [*1*], people suggesting that we copy what Ubuntu has done, and people asking for "howtos" because documentation is too scary or too absent for them to read. Yesterday the whole commercial spam on Planet debate started. Its yet another example of how in-fighting[*2*] seems to be the most fun part of Debian for too many. Me? I started and folded a company. I got Debian help and users. Some threw money at me. Joey Hess? Started making the nice-looking ikiwiki-powered branchable.com. Commercial? Yes. Spam? No. I guess there is little I can do. I could quit - as over time I've become less patient dealing with the project as a whole, but simultaneously more interested in dealing with a few specific people. But I suspect the net result would be no change. Either people would say "Ok , bye" or worse still offer my flttry: "Don't go - we lurve you". Meh. I shouldn't write when I'm annoyed, but living in a hotel will do that to you. Footy-Mc-Foot-notes. Cos HTML is hard. Lets go shopping Eat Cake.

1

The Ubuntu forums are largely full of the blind leading the blind. Or equally often the blind being ignored. I do believe that an Ubuntu stackoverflow site would be more useful than forums. But that's perhaps naive. People will still most often say "My computer doesn't work" missing all useful the details. The only obvious gain is you can avoid "me too!!!" comments, and "fix this now or I'm gonna go .. use gentoo?".

2

Back a few years when people were less civil some mailing lists and irc channesl were unpleasant places to be. These days we've solved half the problem: People mostly don't swear at each other. The distractions, the threads that don't die, even if you ignore them and don't join in the "hilarity" they still have a devisively negative effect.

Want to use a network tarpit? It s so easy to set up! Thanks to jpds for this whole post. :)

sudo module-assistant auto-install xtables-addons-source
sudo iptables -p tcp ... -j TARPIT

Though no such thing exists for IPv6 yet. Here it is watching over the SSH port:

iptables -N INGRESS-SSH
iptables -A INPUT -p tcp --dport 22 -m state --state NEW -j INGRESS-SSH
iptables -A INGRESS-SSH -p tcp --dport 22 -m state --state NEW -m recent --name SSH --set
iptables -A INGRESS-SSH -p tcp --dport 22 -m state --state NEW -m recent --name SSH --update --rttl --seconds 60 --hitcount 4 -j LOG --log-prefix "[INGRESS SSH TARPIT] "
iptables -A INGRESS-SSH -p tcp --dport 22 -m state --state NEW -m recent --name SSH --rcheck --rttl --seconds 60 --hitcount 4 -j TARPIT

Someone on Hacker News asks about the future of programming languages, and I realized that it's a pretty interesting topic. Here's my take on it: Programming languages are about people, and the compromises they may or may not make in order to communicate their intentions to computers. The technology in question may change, but there will likely always be people involved, and as long as that's true, looking at the problem through the lense of economics provides useful results. Therefore, looking at programming languages pretty much requires that you look at the economics of them:

• Network effects are important, but obviously don't squeeze out smaller languages entirely. I.e. it's good to be able to get libraries, find people to hire, books to read, friends to chat with about problems, etc... This means that future languages will have to seek out a critical mass of users.
• Since the times of Fortran, languages have been getting more efficient in terms of programmer time, because programmer time stays the same or gets more expensive, while computer time keeps getting cheaper, and language implementors keep getting better at making things fast under the hood. This means that languages of the future are likely to let you do more with less, all else being the same.
• Learning a programming language will continue to be a fairly involved process for most people, meaning that for many, it's more efficient to learn a few languages well and use them for as much as possible, rather than to try and find the 'perfect' language for each problem. This rewards general-purpose languages, compared to niche languages. This also rewards flexible languages that can be used in many different environments.
• Computers are only going to become more and more important, meaning that more people are going to want to develop the skills to work with them. Not all of them will be experts, and many may not know much, but have a vision for how a program could solve a particular problem in a field they are knowledgeable about. This means a low barrier to entry is important, because those novices will pick easier languages, become progressively more competent in them, and thus (network effects) contribute to their diffusion. Case in point: PHP. Future languages should be capable of solving hard problems, but should also make it easy to get started solving simple problems too.
• Working on languages is lots of fun, so even though there aren't necessarily monetary rewards, people will continue to play with and explore new ideas. I don't see there being a limited supply of new languages in the future.
• The costs of switching from established languages will continue to be high, so future languages will still need to interact with "legacy" languages like Cobol, Fortran, C, Java, and so on, that are so widely established in industry that systems written in them will be with us for a long time yet.

I wrote this in a hurry. Have I missed anything? How do these factors apply to languages you see emerging?

The Italian L10N team has not been very active nor growing in recent years. In particular, we pretty much failed at attracting new members in our team, with the result that untranslated files are piling up and manpower is scarce. Following a suggestion of our uber-active Francesca, we decided to try a new move to invert the trend: organizing brief weekly online sprints open to everybody, where graybeard translators will help newcomers getting to grips on Debian L10N infrastructure while collaboratively working on yet-untranslated targets. Last week, we tried our first and very introductory sprint, with a preliminary meeting on IRC to give instructions and setup ad-hoc pads. As a result, we ended with linux-2.6 po-debconf and a web-page completely translated and proofread by almost fifteen people in just a couple a hours. The key point however is that the majority of participants were fresh L10N-newbies, which we hope will join us permanently very soon after this first contact. Encouraged by the initial positive result, we already announced our next sprint for Thursday 11th, which will be focused on package descriptions translation (preceded by a crash course on DDTSS, its related web interface). We hope that even more users will join us this time, and encourage other stalled translation teams in experimenting a similar approach to revive activity and encourage participation.

It finally happened! I would like to thank all my sponsors since my starting contributing to Debian in 2006. Also, cheers to my AM, Adeodato Sim (dato). It has been quite a long NM process due to us both being quite busy with other things but all in all it has been a very pleasant experience.

I wrote yesterday about our scare with Jacob. It s been quite the day. Before I go into it, I want to say thank you to all the many of you that have sent comments and support our way. Terah and I haven t had the chance to reply to many of them, but we have read every one, and very much appreciate it! Terah spent the night with Jacob, and I spent the day with him today (others were present for parts of it too). Jacob was mostly in good spirits. He was up and around, pushed his IV around himself in the room and to the bathroom. He called it my VI machine (not a typo take that, Emacs, eh?) He continued to enjoy measuring his trips to the bathroom. We went exploring a few times. He would walk or run down one of the long corridors in the hospital, holding my hand, while I pulled the IV along. We often went by the cafeteria, which he called the kitchen. One time he insisted that I get a cup of coffee from the free coffee dispenser. I insisted that I didn t want to, but eventually asked, Shall I get a pretend cup of coffee? Yeah! So he watched me get a pretend cup, pretend to fill it, and pretend to drink it and smiled and clapped for me after. He spent hours watching videos of trains on YouTube. This is a favorite activity at home too, but we obviously limit the amount of time he can spend doing it. I had to limit the amount of time he spent with it today too, of course, but he got rather more time with it than usual. Jacob had his usual books, but I thought we might try something new today. This morning, I loaded The Tale of Peter Rabbit (with illustrations) onto my Kindle. Jacob loved it, and enjoyed pressing the Next Page button in the Kindle. We read it twice, and he is interested by the promise of other stories about rabbits. It also probably didn t hurt that his grandma had given him a rabbit in the hospital yesterday. As we got on towards evening, I told him that tomorrow could be a normal day. His response: enthusiastic applause and a big grin, plus YAY! Jacob loved eating today. He wolfed down breakfast and lunch. He enjoyed the lemonade I brought for him again, and played with some toys, and yes, watched some more train videos in the afternoon. He also pretended to ignore the visitors he got as much as possible (pretty typical for him actually). The doctor came by at about 6:00PM and again was just stunned at how well he s doing. Jacob neither complained of any pain nor acted like he had any even when the nurses would rub neosporin on his wounds. The doctor was still just stunned at how well he was doing. He told us his last tractor accident resulted in a death before LifeWatch could arrive, and the one before that turned a good student and a promising athlete into a wheelchair-bound person with a vocabulary of 20 words. I can t believe I m discharging him today, but try as I might, as I go over all the details, there s no reason for him to stay. I thanked him for all his help, and he said, I didn t do anything for him. All I did was figure out what had happened to him . I guess we have the CT to prove that something really did happen, but the fact that he showed up at my office in the first place was stunning enough. Jacob started to get more excited after the IV was unhooked from him. He didn t particularly like having the needle removed, due to the pain of taking off the tape, but was happy to have it gone. He was making plans: will we stop by the train station on the way home? It s the middle of the night maybe a train will be there! (If it s dark outside, it s middle of the night to him) We agreed to stop by the cafeteria to pick him up one last lemonade, than stop at the train station. The nurses offered a wheelchair to take him out to the car with. I said I didn t think he d want it. One of them said, Wouldn t you like a FUN ride in a WHEELCHAIR? Jacob: No. Me: I suspect he will want to run out of here. Nurse: OK then. We walked, or half ran, to the cafeteria to get his lemonade. Then we went out to the car. He was excitedly jabbering about everything: the car, my radio, and especially the train station. We did drive by, and at least got to see a freight engine go past. He noticed the Christmas lights starting to be set out along Main Street, and said, Dad, it s CHRISTMAS! Well, almost Then he got quiet, and eventually fell asleep in the car. He had almost fallen asleep while eating his lunch, but stayed awake, and then got interested in other things so he had no nap today. When we got home, I unbuckled him and pulled him out of his seat. He opened his eyes for just a second, wrapped his arms tightly around my neck, put his head on my shoulder, and fell back asleep while I carried him up to his room. I put him down on his own bed. He had a contented sigh, pulled his favorite blanket up to his neck like he loves to do, and was back asleep in no time. Our little boy is home, safe and sound. It s a happy day.

State of X in experimental What happened since last month? The video drivers we were previously lacking were built against X Server 1.9, with a tiny exception: xserver-xorg-video-nouveau. This one is particularly annoying because the ABI is not stable, and it requires a particular version of the kernel to be usable. The same seems to happen with the nouveau part of the libdrm library. As a consequence, I ve demoted it from Depends to Recommends for the xserver-xorg-video-all metapackage. The same happened to the xserver-xorg-input-wacom driver (for the xserver-xorg-input-all metapackage this time), since it isn t maintained by debian-x@, and since it didn t look too bad to have it only recommended (after all, we re only targeting experimental right now). In addition, all drivers were updated to the last upstream releases. Bottom-line, the following is now possible on (at least) both amd64 and i386 architectures:

apt-get install -t experimental xserver-xorg

As a side note: Intel users probably want to upgrade their libdrm-intel1 package to 2.4.22-2 (in experimental as well), they could run into X.Org Bug #31443 otherwise. Dependency handling for X packages in Debian Previously, dependencies were quite fun:

• Drivers used to provide a given virtual package: xserver-xorg-input-$ABI and xserver-xorg-video-$ABI. One shall note that the ABI is evolving independently for input and video drivers, see SET_ABI_VERSION in server s hw/xfree86/common/xf86Module.h for curious people.
• The xserver-xorg metapackage depended on xserver-xorg-core (the server itself) with a minimal version, and on those virtual packages. More precisely, for example in the input case: xserver-xorg-input-all xserver-xorg-input-$ABI so that by default one gets everything for autodetection to work, but one can pick a specific driver instead.
• The drivers only depended on the server, with a minimal version as well.

So what did we do to ensure the server and drivers were all using the same ABI? When the server was updated to a new ABI, one had to add the previous virtual packages to Conflicts (and keep a list of all of them, yay!). Needless to say, asking a package manager to upgrade at a same time many packages (several dozens for all drivers) declaring conflicts, especially during a mass dist-upgrade from a stable release to the next stable was no fun. So what s the current situation now?

• xserver-xorg depends on a minimal server version, and on drivers. The alternatives are now written like this: xserver-xorg-input-all xorg-driver-input. Notice there s no ABI mentioned here anymore. It s just about having the server, at least an input driver, and at least a video driver.
• xserver-xorg-core now provides an input ABI and a video ABI. In experimental for example: xorg-input-abi-11.0, xorg-video-abi-8.0
• Drivers now depend on the ABI they were built against. For example, xserver-xorg-input-evdev in experimental depend on xorg-input-abi-11.0

So one might think everything is now fine, except there are some conflicts still declared, to ensure one can transition from packages using the former (bad) logic to the new state of affairs. And those conflicts were still causing headaches to package managers. Fortunately, David Kalnischkies came up with a proposal to replace Conflicts with Breaks, which turned out to ease things. Yatta! All of that is implemented in experimental. squeeze is the transition period where the metapackage stills the depends on xserver-xorg- input,video -$ABI virtual packages, but where drivers now depend on the appropriate server ABI. (Thanks to Alexander Kurtz for his feedback.)

A few months after starting the NM process, I have just been accepted as a Debian Developer. My account name is simply: julien I have been a Debian user for about 10 years now, and have begun contributing to Debian in 2005. I have then been accepted as a Debian Maintainer in 2007. This post is mainly to thank:

• all my sponsors: Christoph Haas (haas) , Lo c Minier (lool), Free Ekanayaka (freee), Maximiliano Curia (maxy) and Micah Anderson (micah),
• my advocate: Matthijs M hlman (matthijs)
• my AM (who actually make it happen in a really short time frame, thanks a lot to him): Xavier Oswald (xoswald)
• all people who helped me during the process, to name a few: Christoph Berg (myon), Enrio Zini (enrico), Peter Palfrader (weasel)

Also thanks to all people who have already sent their congratulations, it makes me very proud!

I had been planning to write today about my great uncle Milt Goerzen. Milt passed away last Thursday after a long struggle with dementia, and his funeral was this morning. I was there, and was inspired by a few things I heard. But that will have to wait, because today brought one of those few moments in life that s a sense of an impending possible great loss. I can remember two others: one was when Terah passed out, and the other was when we heard that our place was on fire and our house had burned down (it turned out the house hadn t, but much of the rest had). I got a call during Milt s funeral. I didn t answer because I was, well, at a funeral, and the phone was on vibrate. When I had the chance to check the voicemail, it went something like this: I think we have an emergency with Jacob. He got run over by a tractor. He says he s OK, but I m taking him to the doctor right now. I tried to return the call, but cell phone reception wasn t cooperating. The most I got was he s OK . It s hard to describe how a moment like that feels. My mind jumped to telling Jacob I love you , and how lately when he hears that, he will snuggle in for a big hug, and say, Dad, I love you toooooooooo! On the one hand, I heard the he s OK part, and on the other hand I couldn t forget the tractor running over him part, and my mind leapt at the worst. It turns out that, while I was at the funeral, Jacob had been standing on his usual spot on the tractor, sort of to the side of the driver. He was enjoying himself like usual. The tractor hit a large hole that wasn t really visible. The combination of the jolt and the dip the tractor took towards Jacob s side knocked him off and he went directly under the big rear wheel before the tractor could be brought to a stop. I caught up with him and his grandpa after he had seen the doctor and just as he was being admitted to the hospital. He saw me and crawled over, making his sort of sad and scared sound he sometimes doesn t want to verbalize things when he s in that mood. I held him close and he seemed to appreciate it. He had to have blood drawn, and he was scared of that. I remembered his inquisitive mind, and reminded him how much he liked watching the tube fill up with blood last time he had a blood test (which he calls a blood shot ). That wasn t helping, until the actual blood test started. He cried when the needle went in, but then calmed down as the nurse, getting into the act, pointed out that there was blood filling up the tube. Hmmm! said Jacob. Then she gave him a band-aid. It has an airplane, said the nurse. Um-hmm! said Jacob. I pointed out that it looked like the airplane we were on when we flew home from New York. Jacob got a big smile and said, Yes, it IS that one! He got a sticker there too. Then it was off for an x-ray to check for broken bones and a CT scan to check for internal injuries the tractor had gone right over his abdomen. He had to get an IV at the CT scan, which he certainly didn t like. After it happened, however, he found it very interesting especially when the nurses explained that they would give him a drink through the hose attached to his hand. After that, we went to his room, with orders for him not to eat or drink anything until it was clear he didn t have digestive problems. While we waited at various steps along the way, Jacob wanted to sit on my lap and watch train videos on YouTube on my phone. He loves train videos, and brought my phone s battery nearly to depletion through the course of the afternoon. Jacob eventually seemed to get back to a bit of his usual self. At one point, while Terah had made a run home to pack an overnight bag and grandpa ran some errands of his own, Jacob wanted to leave the room. He had gone exploring in the hospital with me before: when Oliver was born, and when Terah had her thyroid surgery. So this was something he just associated with the hospital. That and lemonade, which is free any time of the day or night in the cafeteria. So we went exploring, even ventured outside into a courtyard for a bit. He was walking fast and seemed good. We had several visitors: grandparents and his aunt and uncle. Jacob got a stuffed rabbit and a colorful bug box with windows (for putting bugs inside for observation). Eventually the doctor came by and gave us the results: the x-rays showed no problems. The labs showed some elevated liver enzymes, which he expected, but no serious trouble. The CT showed contusions on his lung and bruising on his heart which would heal completely in time. He allowed Jacob to have a liquid supper (so I quickly got him the lemonade he had been wanting while the nurses got him some Jello). The doctor examined Jacob, pushing at various places, asking Does it hurt here? No. Does it hurt here? No. Here? No. Are you hungry? Yes. Does it hurt here? No. He gave me a look that said: really? It doesn t hurt ANYWHERE? What could I do but shrug my shoulders? Jacob has some abrasions on his face, arms, and back, which will probably eventually hurt (and sure enough, about 10 minutes later he started getting a little pain when he tried to move, which the doctor checked out) Then the doctor said, I hope you know you have a walking miracle today. This is just amazing. You have some thanking to whatever guardian angels you like tonight all I can say about this is that the Lord must have had some other plan for him. There s no way he could have survived that. Jacob s doctor is one that we really respect: he s scientific in his analysis, cites studies as a matter of routine, doesn t prescribe antibiotics for things that he knows they have a small chance of helping, is common-sense about not over-treating things and yet always engaged in an emergency. That little speech from him was something I d never expected to hear from him. He went on to add that I always visit my sickest patients first. You were my last visit this evening, so that should tell you something. Any other kid as healthy as he is, I might discharge already but I m just not justified doing that with a boy that s, well, been driven over by a tractor this morning. He also wanted to monitor Jacob s progress throughout the coming day, especially his digestive system. They wanted to measure his urine output, which he, predictably, found to be very interesting. Terah said I think it is about 150 ml. Jacob said, No mom, it is closer to the two hundred line. Me: Since when does Jacob know about the number 200? Terah: I don t know . he s 4, where would he have gotten it? Between that, and using every opportunity to tell people that there were not one but TWO red light switches in the x-ray room, Jacob s definitely himself in some ways already. So, that feeling of some impeding great loss is gone, replaced by being more than a bit overwhelmed by how fortunate we were today. We also appreciate all the help we ve had with Jacob and Oliver today.

Most of my recent Debian work has been the usual pkg-telepathy stuff (mainly in experimental while we're frozen), and hacking on the Quake III engine. Having started working on OpenArena DFSG-freeness as random bug-squashing a year ago, I've accidentally ended up taking over the package. The situation for Debian 6.0 (squeeze) looks something like this:

• openarena contains both the engine (a modified ioquake3, which I modified further for Debian) and the game logic compiled to native code
• openarena-data has had the bytecode game logic stripped out, since no Free compiler can produce it; the bytecode has been replaced with stub files that direct our modified engine to load native code

The plan for Quake III in Debian 7.0 (wheezy) has already started in experimental:

• ioquake3 contains the ioquake3.org port of the Quake III engine, which I've modified to be able to run either Quake III Arena or OpenArena based on runtime options
• openarena contains the game logic compiled to native code (in experimental it still contains source code for the engine, but it's no longer patched or compiled, and I'll hopefully drop it entirely after the next upstream release), and launcher scripts to run it under the ioquake3 engine
• openarena-data is much like it is now, although it might move to data.debian.org if that happens
• quake3 (currently in the NEW queue) contains launcher scripts to run Quake III Arena under the ioquake3 engine, requiring a non-distributable quake3-data package
• game-data-packager version 23 or later can build the quake3-data package for local use, if you give it pak0.pk3 (from the CD-ROM) and the latest Quake III patch

I haven't been doing as much QA work as the RCBW crowd, but here's some halfway-recent bug squashing in the hope that it motivates others:

• alsa-lib Debian bug #589896 upstream patch backported, NMU'd and herded into testing
• atftpd Debian bug #598474 downgraded
• courier-authlib Debian bug #554788 patch submitted, uploaded
• isc-dhcp Debian bug #592361 patch submitted, uploaded by maintainer by maintainer
• mixxx Debian bug #587110 patch submitted, acked by maintainer
• tar Debian bug #602184, Debian bug #602209 upstream patches NMU'd
• witty Debian bug #591209 patch submitted, although it doesn't list copyright holders so probably isn't suitable for upload

I also started looking at the series of bugs regarding Flash not compiled from source, but I mostly got distracted by all the webapps having a contrib/ directory containing a million embedded code copies...

Now that we have KMS, it happens things go bad enough that when X goes down, one can no longer access any console to see what happened. Mainly, one can distinguish between two cases.

• The good one: the machine is still accessible over the network. Unfortunately, that requires having a spare machine to ssh into the first machine, but that means one can run dmesg, look into X logs, possibly run X inside gdb and see where it breaks (because glibc s backtrace isn t exactly an excellent tool to get the idea of what s going on and that s the tool used in X to print a backtrace in the log through a signal handler).
• The bad one: the machine is no longer accessible over the network. Likely, the kernel is in such a bad shape that one is never going to know what happened. Usually, writing logs to disc didn t happen, so logs won t magically show up at next reboot.

I m going to discuss the second case. There s a nice tool in the kernel which makes it possible to send kernel logs over the network. It s called netconsole. As far as limitations are concerned, one shall note that it s UDP only, and over Ethernet (in other words: no wireless). The good news is that it can usually make the last crucial lines available. Let s call the crashy machine a patient and the logging machine a doctor. One should keep in mind that if something goes wrong while configuring the netconsole module, it can be unloaded at anytime through:

sudo modprobe -r netconsole

Easy case: on a local network Here s an example: Patient s IP is 192.168.0.1, doctor's IP is 192.168.0.2. Doctor setup What one needs on the receiving side: only netcat. A tiny warning, there are several implementations. Here s the appropriate syntax:

# netcat-traditional:
nc -l -u -p 6666   tee ~/netconsole.log
# netcat-openbsd:
nc -l -u 6666   tee ~/netconsole.log

The nc command is handled through the alternatives system, one can use update-alternative --config nc to pick the appropriate one if several netcat-* packages are installed. To list the current one, an easy way is readlink -f $(which nc). Using tee means that incoming messages are going to be printed, both to the standard output and to the specified file. Running as non-privileged user is sufficient. Patient setup Now, to have the patient send stuff to the doctor, a simple modprobe is needed:

sudo modprobe netconsole netconsole=@/,6666@192.168.0.2/

What happens here? One requests the netconsole module to be loaded, and one specifies the parameters. Details can be read in the Linux kernel documentation (Documentation/networking/netconsole.txt), but concentrating on the points of interest here:

• 192.168.0.2: The doctor s IP.
• 6666: The UDP port to which packets are sent. 6666 is the default and can be omitted.

That s all! On the doctor side, one should see something along those lines:

[2920549.188090] console [netcon0] enabled
[2920549.188102] netconsole: network logging started

Slightly harder case: over internet Because one might not have a second machine handy, it s also possible to go through a router and send stuff across the internet. Here s an example: Patient s IP is 192.168.0.1, connecting to internet through a router, which IP is 192.168.0.254. The doctor, available over the internet, is 192.0.32.10. Doctor setup Exactly the same as in the previous case. The main issue one can run into is firewalls at this point. That s why one may want to switch from the default 6666 port to another one which wouldn t be filtered. One can think of 53 (DNS), but that means running nc as root since it s a privileged port (below 1024). Patient setup Routing is also possible, but that requires an extra parameter: the MAC address of the router. To obtain it, one can use the arp command:

/usr/sbin/arp 192.168.0.254

Supposing it returned the 01:02:03:04:05:06 address, loading the module becomes:

sudo modprobe netconsole netconsole=@/,6666@192.0.32.10/01:02:03:04:05:06

Now, if you re running into firewall-related issues, you can change the source for the UDP packets. The default is 6665, but assuming you want to send from an unfiltered 1234 port, that becomes:

sudo modprobe netconsole netconsole=1234@/,6666@192.0.32.10/01:02:03:04:05:06

On 24th of October we've been to the concert of Unheilig. It was actually very touching, even though the sound quality of the venue was disappointing. Here are the common three songs that I usually share about bands that I like to introduce you to:

• Mein Stern: Even though it's not my star in those pictures, the song still gives me goose bumps.
• Geboren um zu Leben: He wrote this great song for his best friend that isn't anymore.
• An deiner Seite: Another truly great of their songs. Let it touch your soul.

I am aware that these songs are all pretty emotional and rather quiet. Unheilig has also a much harder side to them. It's just that my current mood is pretty emotional, that's also the reason for this selection.

/music permanent link Comments: 0

Even though we had approximate dates from very start, I would like to announce official dates when DebConf11 will be held in Banja Luka, Bosnia and Herzegovina.


DebCamp: 25th 31st July 2011 DebConf: 1st - 7th August 2011
We encourage you to arrive one day earlier (24th July for DebCamp, and 31st July for DebConf), final departure date will be 8th August.
Vacation, it s in our plans to talk to travel agencies, so for those who wanted vacation after DebConf11 as its participants can enjoy shores of Bosnia, Croatia, Montenegro and Greece by discount prices. We re already looking forward your stay on Balkans! Adnan


http://wiki.debconf.org/wiki/DebConf11/BanjaLuka

Last week, I worked on my Google Maps for Emacs extension. I've introduced a new format handling for locations which include the longitude and latitude. The initial format was just a string describing the location, which was obviously too limited. It now prints coordinates of the different elements when the mouse is over the map, with other information. It also center the map on M-x google-maps and set a default zoom level. This is something which was not set because it's not a good idea to set center coordinates in order to see all points on the map automatically. But you can still remove the centering by pressing "C". On the other hand, setting it automatically allows to move the map easily, and I think that what most users want to do. I've also added a "place my home on the map" feature, accessible by pressing "h" on any map. That adds a marker according to the location set in Emacs using the calendar- variables. This feature is also available under Org by pressing C-u C-c M-l, which shows the location of your appointment with your home on the map too. Finally, you also get caching so it does not request images you already seen, which makes the moving nicer and faster to use, and prompt history.

You re probably manipulating Debian packages everyday, but do you know what those files are? This article will show you their bowels Surely they are more than file archives otherwise we would just use TAR archives (you know those files ending with .tar.gz). Let s have a look! 1. It s two TAR file archives in an AR file archive! A .deb file is actually an archive using the AR format, you can manipulate it with the ar command. This archive contains 3 files, you can check it yourself, download any .deb file and run ar t on it:

$ ar t gwibber_2.31.91-1_all.deb
debian-binary
control.tar.gz
data.tar.gz

debian-binary is a text file indicating the version of the format of the .deb file, the current version is 2.0 .

$ ar p gwibber_2.31.91-1_all.deb debian-binary
2.0

data.tar.gz contains the real files of the package, the content of that archive gets installed in your root directory when you run dpkg --unpack . But the most interesting part which truly makes .deb files more than a file archive is the last file. control.tar.gz contains meta-information used by the package manager. What are they?

$ ar p gwibber_2.31.91-1_all.deb control.tar.gz   tar tzf -
./
./postinst
./prerm
./preinst
./postrm
./conffiles
./md5sums
./control

2. It contains meta-information defining the package and its relationships The control file within the control.tar.gz archive is the most fundamental file. It contains basic information about the package like its name, its version, its description, the architecture it runs on, who is maintaining it and so on. It also contains dependency fields so that the package manager can ensure that everything needed by the package is installed before-hand. If you want to learn more about those fields, you can check Binary control files in the Debian Policy. Those information end up in /var/lib/dpkg/status once the package is installed. 3. It contains maintainer scripts so that everything can just work out of the box At various steps of the installation/upgrade/removal process, dpkg is executing the maintainer scripts provided by the package:

• postinst: after installation
• preinst: before installation
• postrm: after removal
• prerm: before removal

Note that this description is largely simplified. In fact the scripts are executed on many other occasions with different parameters. There s an entire chapter of the Debian Policy dedicated to this topic. But you might find this wiki page easier to grasp: http://wiki.debian.org/MaintainerScripts. While this looks scary, it s a very important feature. It s required to cope with non-backwards compatible upgrades, to provide automatic configuration, to create system users on the fly, etc. 4. Configuration files are special files Unpacking a file archive overwrites the previous version of the files. This is the desired behavior when you upgrade a package, except for configuration files. You prefer not to loose your customizations, don t you? That s why packages can list configuration files in the conffiles file provided by control.tar.gz. That way dpkg will deal with them in a special way. 5. You can always add new meta-information And in fact many tools already exploit the possibility to provide supplementary files in control.tar.gz:

• debsums use the md5sums file to ensure no files were accidentally modified
• dpkg-shlibdeps uses shlibs and symbols files to generate dependencies on libraries
• debconf uses config scripts to collect configuration information from the user

Once installed, those files are kept by dpkg in /var/lib/dpkg/info/package.* along with maintainer scripts.

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Hello World. I am very pleased to announce apt-offline, version 1.0. This release adds a Graphical User Interace to apt-offline. Big thanks to Abhishek Mishra and Manish Sinha who did all the development work to make this GUI happen. Help: I was wondering if there is a logo for APT that I could use in the big blank space on the main window. Apart from the GUI, there are a bunch of bug fixes in this release (which have already been made available for the Squeeze release also). I look forward to your feedback and comments on the GUI front. Note: The GUI in its current form is basic and does not provide all the features that are available in apt-offline.