Search Results: "tach"

19 June 2014

Russell Coker: Phone Car Accessories

Tree Frog Dashboard Mat phone stuck to fridge I ve been given some more MobileZap products to review. The first is the Tree Frog anti-slip dashboard mat [1]. This is designed to allow a phone to stick to an angled surface of the inside of the car without slipping. The pictures on the web site show a phone stuck to a curved angular surface of a car dash. To test this I stuck my phone to my fridge, the flat metal surface of the fridge and the almost flat plastic surface of the gel case of my phone are pretty much ideal surfaces for the sticky mat to adhere to. But even so keeping my phone stuck to a vertical surface is impressive. This mat is cheap enough that it could be used for many other tasks than securing a phone in a car, for example it could be used to stick a phone to the wall of your office. It s apparently washable and can be expected to keep gripping things if washed regularly. One thing that could be improved in the mat would be to have some holes in it. When I detached my phone from the fridge some large air bubbles developed between the mat and the fridge, this would be a problem if I wanted to regularly stick my phone to a flat surface such as an office wall. When in my car it didn t work nearly as well. The pattern on the surface of the car dash which is designed to avoid glare when driving is difficult to stick to, it s a bit like trying to attach sticky-tape to unpainted wood for similar reasons. A phone will still remain in place on a 30 degree angle from the horizontal (which is significant) but the mat grips much more tightly to the phone than the dash, which is a little inconvenient as the mat stays attached to the phone when you remove it from the dash. Sorry for the boring picture, it s black and flat so there s not much scope for making it interesting. 3.1A USB Car Charger AA battery charger and 3.1A car charger Above is a picture of a 3.1A USB car charger and a AA battery charger. The car charger isn t particularly exciting, but providing 3.1A through two USB sockets is noteworthy it can charge one device at 2.1A (the maximum any device draws) or two devices for a total of up to 3.1A [2] (with protection against over-current). Previously in my car I used the 2.1A charger that shipped with my Galaxy Note 2 and an inverter to provide 240VAC as the devices I had to charge a phone from a car socket didn t provide enough current. This new device uses less space and also allows charging two phones at once. One problem with this device was finding USB cables that could handle the current, for benchmarking I used a phone that was running Ingress and acting as a Wifi access point. I discovered that the cables that Samsung ships with their recent devices (Galaxy Note 2 and Galaxy Note 10.1 tablet) seem to work best and support charging my Galaxy Note 2 or my wife s Nexus 5 while playing Ingress and running as a Wifi AP. Most of the other cables that I have in my collection won t even allow a phone to remain at the same charge level while playing Ingress. AA Emergency Phone Charger The AA phone charger is best suited for emergency use only, it takes one AA battery and has limited current capacity [3]. A NiMh rechargeable battery has a nominal Voltage of 1.2V, to provide 5V to charge a phone the Voltage has to be boosted by a factor of 4.16 which would reduce the current by a factor of 4.16 if the charger was 100% efficient. As 100% efficiency is impossible the current would be reduced even more. It seems unlikely that a AA battery would be able to sustain a current of 2A so the supply from that charger would be less than 500mA IE less than the least capable PC USB port or mains powered phone charger. A test with a Nexus 5 showed the phone charge level decreasing while being very lightly used (mostly just checking whether the charge level was increasing) when a NiMH battery was connected. A test with an alkaline battery and the same Nexus 5 showed the phone charge level increasing when lightly used but it probably wouldn t do so while playing Ingress. It seems that a single NiMH AA battery can only be used for charging a phone in a real emergency situation (IE an act of god type disaster not a need to level up in Ingress). If mains power was out then you could charge a phone while it s turned off (AFAIK all Android phones support this) and then use it once it s charged. This charger supports a wide range of phones (including LG phones from 5+ years ago and Nokia from ~10 years ago) so it could be good for charging an old phone in an emergency. Older phones need less power to charge and generally last longer between charges. With an alkaline battery the charger works a lot better, but it s still for emergency use as I generally only use rechargeable batteries. This is a device I might put in the bottom of my case when travelling, not a device that I ll use regularly. I don t think that this is a deficiency in the product, it s just a limit of what can be done with the power requirements of modern phones and the capabilities of AA batteries. If you want a battery to use while playing Ingress you definitely need something a lot larger. This charger is good for emergencies but not suitable for my main use (charging phones while playing Ingress) so I ll give it to my parents, they do a lot of hiking and camping and my father often goes fishing. Taking a few AA batteries to charge a phone would be much more convenient for such use than taking one of the larger batteries I use for Ingress. Also as the charger is relatively cheap there s less potential financial loss if you drop it in sea-water. 20800mAh Battery picture of 20800mAh USB battery Above is a picture of a 20800mAh battery pack that MobileZap sent me [4]. I haven t yet discovered what it s capacity is, during the recent Interitus anomaly it kept my Galaxy Note 2 and my wife s Nexus 5 adequately charged for 5 hours of intensive Ingress playing (we alternated between phones). Without an external battery it would be unusual for either of those phones to last for 2 hours. The battery has two ports labeled 1A and 2.1A which implies that it can supply a total of 3.1A. I am a little dubious of that implication. After the Interitus anomaly my wife and I had dinner with some friends and I let a friend charge her Samsung Galaxy S5 on the battery at the same time as my Note 2 (which claimed to be 2% charged). When I connected my friend s phone my phone instantly shut itself down due to lack of charge, so I presume that the supply on the 2.1A port is reduced when a demanding device is connected to the 1A port. The next day my wife and I went to the city again to play Ingress and attend a protest against some of the awful things that the Abbott government is doing. As an experiment I didn t charge this battery to see how it would go for two days of use charging two phones. Again there was no problem and it still claimed to be half charged when we got home. So far the only problem I ve found with this battery is that it never reports being fully charged, not even if I leave it on charge for days. That doesn t seem to be a great problem to me, if I disconnect it before it s fully charged then that won t hurt the battery life (unlike NiCd batteries that have to be fully charged every time) and even if it s not fully charged it will still charge phones for a long time. The battery is about 19cm long. I have jeans with unusually large pockets to fit large phones [5] so I can fit this battery in my pocket while a USB cable is connected to charge my phone. I also have a new winter jacket from Scottwear which has pockets that can fit the battery (and lots of other things). Anyone who doesn t have such clothing should plan to use a backpack, handbag, or some other bag this type of battery won t fit in the pockets in most clothing. MobileZap also has some other interesting Nexus 5 accessories [6].

B lint R czey: Run Wireshark on Android using Lil Debi!

Running Wireshark for Android has been an dream for a long time. Now it became a reality!
Wireshark running on Android using Lil'Debi

Wireshark running on Android using Lil Debi

You only need a rooted Android device with ~2GB free space, Internet connectivity and some patience to follow the steps below.
  1. Install Lil Debi from Google Play or F-Droid. Lil Debi will install a Debian root file system in a loop device separately from the Android file system allowing us running Debian side-by-side to the Android apps.
  2. Start Lil Debi and create the Debian system with 2000 MB image size. We will need some space for Wireshark, the graphical interface Wireshark depends on and for the capture files.
  3. Start the newly created Debian system and log in to it. You will see the error message bash: [: : integer expression expected , but you can continue.
  4. Now run the following commands at the command line to install all the packages Wireshark will need:
    # some important directories are missing from the PATH by default
    export PATH=/sbin:/usr/sbin/:$PATH
    # we will start an X server later
    export DISPLAY=127.0.0.1:0
    # install wireshark an a few things to make it nicer
    apt-get install openbox gnome-themes-standard tshark wireshark
    # gnome-settings-daemon depends on plenty of packages we don't need now,
    # but we need gnome-settings-daemon for the GNOME theme to be applied
    apt-get install --no-install-recommends gnome-settings-daemon
  5. To run graphical applications from the Debian chroot we need to set up an X server on Android because Android uses a different method for presenting the GUI. XServer XSDL is available from Google Play and from SourceForge. Install and start it. It will show the display it is serving which will most probably end with :0, so the DISPLAY environment variable we set before is correct. (If there is an other number after the : , fix your DISPLAY variable.)
  6. Start the openbox window manager, gnome-settings-daemon and finally wireshark in capturing mode:
    openbox &
    # if you would like to have bigger menu fonts skip starting gnome-settings-daemon
    gnome-settings-daemon &
    wireshark -k -i wlan0
    
  7. Switch to the X server to see wireshark starting up, close the warning dialogs start capturing traffic!
I tested the tests above using a Nexus 7 (Asus 2013 version) running CyanogenMod M7, thus root access was granted by default, Lil Debi 0.4.7, and XServer XSDL 1.11.14.

18 June 2014

Matthias Klumpp: Tanglu 2 (Bartholomea annulata) status update #1

bartholomea-annulata

Bartholomea annulata (c) Kevin Bryant

It is time for a new Tanglu update, which has been overdue for a long time now! Many things happened in Tanglu development, so here is just a short overview of what was done in the past months. Infrastructure Debile The whole Tanglu distribution is now built with Debile, replacing Jenkins, which was difficult to use for package building purposes (although Jenkins is great for other things). You can see the Tanglu builders in action at buildd.tg.o. The migration to Debile took a lot of time (a lot more than expected), and blocked the Bartholomea development at the beginning, but now it is working smoothly. Many thanks to all people who have been involved with making Debile work for Tanglu, especially Jon Severinsson. And of course many thanks to the Debile developers for helping with the integration, Sylvestre Ledru and of course Paul Tagliamonte. Archive Server Migration Those who read the tanglu-announce mailinglist know this already: We moved the main archive server stuff at archive.tg.o to to a new location, and to a very powerful machine. We also added some additional security measures to it, to prevent attacks. The previous machine is now being used for the bugtracker at bugs.tg.o and for some other things, including an archive mirror and the new Tanglu User Forums. See more about that below :-) Transitions There is huge ongoing work on package transitions. Take a look at our transition tracker and the staging migration log to get a taste of it. Merging with Debian Unstable is also going on right now, and we are working on merging some of the Tanglu changes which are useful for Debian as well (or which just reduce the diff to Tanglu) back to their upstream packages. Installer Work on the Tanglu Live-Installer, although badly needed, has not yet been started (it s a task ready for taking by anyone who likes to do it!) however, some awesome progress has been made in making the Debian-Installer work for Tanglu, which allows us to perform minimal installations of the Tanglu base systems and allows easier support of alternative Tanglu falvours. The work on d-i also uncovered a bug which appeared with the latest version of findutils, which has been reported upstream before Debian could run into it. This awesome progress was possible thanks to the work of Philip Mu kovac and Thomas Funk (in really hard debug sessions).
Tanglu ForumsTanglu Users We finally have the long-awaited Tanglu user forums ready! As discussed in the last meeting, a popular demand on IRC and our mailing lists was a forum or Stackexchange-like service for users to communicate, since many people can work better with that than with mailinglists. Therefore, the new English TangluUsers forum is now ready at TangluUsers.org. The forum software is in an alpha version though, so we might experience some bugs which haven t been uncovered in the testing period. We will watch how the software performs and then decide if we stick to it or maybe switch to another one. But so far, we are really happy with the Misago Forums, and our usage of it already led to the inclusion of some patches against Misago. It also is actively maintained and has an active community. Misc Thingstanglu logo pure KDE We will ship with at least KDE Applications 4.13, maybe some 4.14 things as well (if we are lucky, since Tanglu will likely be in feature-freeze when this stuff is released). The other KDE parts will remain on their latest version from the 4.x series. For Tanglu 3, we might update KDE SC 4.x to KDE Frameworks 5 and use Plasma 5 though. GNOME Due to the lack manpower on the GNOME flavor, GNOME will ship in the same version available in Debian Sid maybe with some stuff pulled from Experimental, where it makes sense. A GNOME flavor is planned to be available. Common infrastructure We currently run with systemd 208, but a switch to 210 is planned. Tanglu 2 also targets the X.org server in version 1.16. For more changes, stay tuned. The kernel release for Bartholomea is also not yet decided. Artwork Work on the default Tanglu 2 design has started as well any artwork submissions are most welcome! Tanglu joins the OIN The Tanglu project is now a proud member (licensee) of the Open Invention Network (OIN), which build a pool of defensive patents to protect the Linux ecosystem from companies who are trying to use patents against Linux. Although the Tanglu community does not fully support the generally positive stance the OIN has about software patents, the OIN effort is very useful and we agree with it s goal. Therefore, Tanglu joined the OIN as licensee.
And that s the stuff for now! If you have further questions, just join us on #tanglu or #tanglu-devel on Freenode, or write to our newly created forum! You can, as always, also subscribe to our mailinglists to get in touch.

17 June 2014

Tiago Bortoletto Vaz: Little garden project

After three years living in Montr al we're still amazed by the fact that here we have er... seasons!! I believe that things have a special beauty when they don't last the time we want them to last, and seasons are all about it! (some people will exclude winter here) Anyways, taking pictures may give them more lifetime without compromising too much their beauty. And sharing them here and there is somewhat sharing our happiness, which might be a good balance in the end :)
/images/01.JPG

At the time we moved the garden was just a single white thing...

/images/02.JPG

then we realized that it provided some chairs, a table and a compost container, yay!

/images/03.JPG

But the grey ground was something to be fixed...

/images/04.JPG

so we hacked it and got some land :)

/images/05.JPG

Few months later and it's finally becoming chard, beets, carrots, spinach, berries, cheries, okra, tomatoes, basil, potatoes, sage, agastache and a saskatoon berry tree!

10 June 2014

Gunnar Wolf: Tor: I'm shutting down my relay only after four days

Some days ago, I bit the bullet and accepted the Tor Challenge. Sadly, after only four days of having a Tor relay node happily sitting at home (and, of course, giving a nice function to this little friend). The inconveniences were too many. I understand anonimity can be used for many nefarious things, but I was surprised and saddened to see the amount of blocking services. Most notorious to me were the Freenode IRC network, friendly home to many free software projects, and the different Wikimedia projects, which ban editting from IP addresses idenitfied as Tor relays. I'm saddened to say that, while I could perfectly survive (and even be a bit proud about supporting a project I believe in) by jumping through some hoops (i.e. by setting up a SOCKS over ssh tunnel to my office to do my Wikipedia edits while at home), after only four days, I decided to shut down my relay. And the main reason... Was something I'm not going to fight against. And it's not even from a nice, friendly free software project. One thing I am not willing to part with is the one tool that keeps my wife well in contact with her friends and family back in Argentina. Yes, I know I could set up one or many different flavors of SIP or Jabber-based VoIP for her But it's also her parents, brother, sisters, and friends who use Skype. So, Skype's banning of Tor relay nodes made me decide to shut down my relay. Sigh... And for somebody obsessed with graphing stuff, this is the graph of the short lifespan of the "Lobazal" Tor node: [update] I will do another blog post. Good news: My Tor node is alive again! Just no longer as an exit relay, as properly pointed out by many, but as a Tor bridge.
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4 June 2014

Russell Coker: Android Device Service Life

In recent years Android devices have been the most expensive things I ve purchased apart from airline tickets and other travel/holiday expenses. As they are expensive I d like to use them for as long as possible to get the most value for money. Also as I give my devices to relatives when they no longer work for me I d like to avoid having relatives hassling me about their phone not working as desired. So I ve been thinking about the features that I need to make it possible to use a phone or tablet for a long time. RAM The way Android works is that when an application in the foreground requests more memory background applications may be closed to free some memory. Android doesn t use swap by default, there is some documentation on how to enable it (and it s not difficult to figure out for anyone who has used Linux before) but generally it s not done. If you run a larger application the chances of apps closing in the background (causing delays when you switch back to them and possibly a loss of context if the app is buggy and doesn t preserve all state) are increased. As a general trend apps tend to get bigger to provide more features and also because users who own newer bigger devices don t complain as much about memory use. Also to make things worse new versions of Android tend to use more RAM. So a phone that runs well can suddenly start performing badly when you upgrade to a new version of Android (which incidentally usually can t be reversed) and upgrade to new versions of apps (which can t be reversed through the Google Play Store). The Sony Ericsson Xperia X10 was a very nice phone when it was released, it ran Android 2.1 very quickly. When I upgraded the Xperia X10s that my wife and I used to Android 2.3 (which was necessary to have the phone run as a Wifi access point) performance dropped considerably. The Android upgrade combined with newer larger apps means that those phones are barely usable now. 384M of RAM was plenty in early 2011 when I first used the Xperia X10 but it s not nearly enough now. Recently 2G of RAM has been the minimum for a mid-range or high-end phone. It seems difficult to imagine a new Android feature as compelling as the addition of Wifi access point support in Android 2.3 that would drive an upgrade to a future memory hogging version of the OS. It also seems difficult to imagine Android apps needing enough memory to destroy the performance of a phone with 2G of RAM. But then I couldn t imagine the 384M in an Xperia X10 becoming inadequate or the 512M in a Samsung Galaxy S becoming barely usable either. Storage Until fairly recently storage in an Android device was divided into USB attached storage (a VFAT filesystem that could be directly mounted on a PC) and a Linux filesystem that was used for all internal operations of the phone. On such devices it typically wasn t possible to change partition sizes without a lot more skill than most users possess and most of the storage space was reserved for USB attachment. If you only had a few Android apps and lots of photos, movies, etc then this worked well. But if you wanted to install larger Android apps then you would have big problems. Even with Android 4.x devices (which all seem to have a single filesystem) you can easily run out of space. Modern games often take several hundred megs of storage. Games that take 500M+ for the Android package install (which also requires the same amount of temporary space for installation and upgrade) are common. Sometimes games download data files after they have been installed for a total size approaching 2G (such as The Sims Freeplay). When I bought a Nexus 4 for my wife I got the version with 8G of storage because paying an extra $50 for the 16G version seemed unreasonable. 8G was fine for my wife, but when she got a new phone I gave the Nexus 4 to a relative who wanted to play The Sims and other big games. That relative isn t so happy about having a limited number of games on their phone and I have to fix it when storage space runs out and things start aborting (when storage runs out the Google App Store program aborts and uses lots of space for temporary files). I recently bought a tablet with 32G of storage and filled 16G on the first day (tablets are good for watching
TV and TV shows are big). Fortunately the tablet in question has a SD socket so that when space becomes a problem in a year or two I can buy an SD card and keep using it. An unfortunate recent decision by Google was to prevent apps from being run from a SD card. So even if you have a device with a SD socket you still need to have enough internal storage for all apps and their private data. At 500M+ for a modern game that means a device with 8G of storage (which includes space for the OS) will be lucky to get 8 games installed. If you want to use a phone to it s full capacity (playing various media files, games, etc) then it seems that the minimum storage capacity would be 8G of internal storage and a SD socket. For a device without an SD socket (such as the Nexus 5 with 16G or 32G of storage) your future use will be limited. 32G is probably enough for a phone given that you can recode movies to use less space (the FullHD screen on the Nexus 5 is nice but 720p movies will probably look good enough). But the larger screens of tablets demand better video quality so the Nexus tablets are probably a bad choice due to lack of storage space. Screen Size and Resolution I have previously written about the sizes of devices and how they may be used by people of various ages [1]. That should be of use for anyone who plans to use their old phone as an educational device for their children (which appears to be very common). But apart from that I can t think of any reason why size would suddenly make an old phone obsolete. Only young children will have their hands change size in any significant way. Resolution also shouldn t be a huge problem, the 480*854 screen on the Xperia X10 is fairly good for a 4 screen. While a higher resolution makes text more readable at a small size for most users the availability of a higher resolution screen isn t going to make their old phone obsolete. CPU The only Android devices I owned that appeared to develop CPU speed issues late in life were the Xperia X10 phones, and that might be more due to RAM limits and the OS upgrade. All the other devices were either obviously slow at purchase time or are still performing well now. CPU speed may make it difficult or impossible to play new games, but shouldn t affect other uses of a phone or tablet. Conclusion It seems to me that if you want to use an Android device for more than 2 years then storage capacity should be a major factor in choosing which device to purchase. It seems that lack of storage space is in many cases the main factor that makes older devices annoying or impossible to use.

2 June 2014

Raphaël Hertzog: My Free Software Activities since January 2014

If you follow my blog closely, you noticed that I skipped all my usual monthly summaries in 2014. It s not that I stopped doing free software work, instead I was just too busy to be able to report about what I did. As an excuse, let me tell you that we just moved into a new house which was in construction since may last year. The lack of visible activity on my blog resulted in a steady decrease of the amount of donations received (January: 70.72 , February: 71.75 , March: 51.25 , April: 39.9 , May: 40.33 ). Special thanks to all the people who kept supporting my work even though I stopped reporting about it. So let s fix this. This report will be a bit less detailed since it covers the whole period since the start of the year. Debian France Preparations related to general assemblies. The year started with lots of work related to Debian France. First I took care of setting up limesurvey with Alexandre Delano to handle the vote to pick our new logo:
The new logo of Debian France I also helped Sylvestre Ledru to finalize and close the accounting books for 2013 in preparation for the general assembly that was due later in the month. I wrote the moral report of the president to be presented to the assembly. And last step, I collected vote mandates to ensure that we were going to meet the quorum for the extraordinary assembly that was planned just after the usual yearly assembly. The assemblies took place during a two days mini-debconf in Paris (January 17-18) where I was obviously present even though I gave no talk besides announcing the logo contest winner and thanking people for their participation.
Assembl e g n rale 2014 de Debian France

The Debian France members during the general assembly

It s worth noting that the extraordinary assembly was meant primarily to enshrine in our bylaws the possibility to act as a trusted organization for Debian. This status should be officialized by the Debian project leader (Lucas Nussbaum) in the upcoming weeks since we answered satisfactorily to all questions. Our paypal donation form and the accounting tools behind it are ready. Galette packaging and members map. I managed to hand over the package maintenance of galette to Fran ois-R gis Vuillemin. I sponsored all his uploads and we packaged a new plugin that allows to create a map with all the members who accept to share their location. The idea was to let people meet each other when they don t live far away with the long term goal to have Debian France organized activities not only in Paris but everywhere in France. New contributor game. Last but not least, I organized a game to encourage people to do their first contribution to Debian by offering them a copy of my book if they managed to complete a small Debian project. We got many interesting projects but the result so far seem to be very mixed. Many people did not complete their project (yet) that said for the few that did substantial work, it was rather good and they seem to be interested to continue to contribute. Debian France booth at Solutions Linux in Paris. Like each year, I spent two days in Paris to help man the Debian France booth at Solutions Linux. We had lots of goodies on sale and we made more than 2000 EUR in earnings during the two days. I also used this opportunity to try to convince companies to support the new Debian LTS effort.
Debian France booth at Solutions Linux

Tanguy Ortolo and Fernando Lagrange behind the Debian France booth

The Debian Administrator s Handbook In the last days of 2013, we released the wheezy update of the book. Then I quickly organized everything needed so that the various translation teams can now focus their efforts on the latest release of the book. Later (in February) I announced the availability of the French and Spanish translations. Debian Squeeze LTS When the security team called for help to try to put in place long term support for Squeeze, I replied positively because I m convinced that it s very important if Debian wants to stay an acceptable choice in big deployments and because I knew that some of my customers would be interested Thus I followed all the discussions (on a semi-private list first and then on debian-lts@lists.debian.org) and contributed my own experience. I have also taken up the responsibility to coordinate with the Debian contributors who can be hired to work on Squeeze LTS so that we have a clear common offer for all the companies who have offered financial support towards Squeeze LTS. Expect further news on this front in the upcoming days/weeks. Tryton I have been a long time user of SQL-Ledger to manage the accounting of my company Freexian. But while the license is free software, the project is not. It s the work of a single developer who doesn t really accept help. I have thus been considering to move to something else for a long time but never did anything. This year, after some rough evaluation, I decided to switch to Tryton for my company. It s probably not a wise choice from a business perspective because that migration took me many hours of unpaid labor but from a free software perspective it s definitely better than everything else I saw. I contributed a lot of bug reports and a few patches already (#3596, #3631, #3633, #3665, #3667, #3694, #3695, #3696, #3697) mainly about problems found in the French chart of accounts but also about missing features for my use case. I also accepted to sponsor Matthias Berhle, who is maintaining the official Debian packages of Tryton. He s already a Debian maintainer so it s mainly a matter of reviewing new source packages and granting him the required rights. Misc Debian work Thanks See you next month for a new summary of my activities.

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Ean Schuessler: Singing tiny robotic Einstein head

Tiny Robot Einstein Head

Work on the ROS/Blender robotics control pipeline has culminated in the integration of the system with the tiny robotic Einstein head that had been living at Polytechnic University under the watchful eye of the OpenCog group. Back at Hanson Robotics, tiny Einstein was mercilessly ripped apart and his head attached to an absurdly long robot snake neck apparatus that mimics the configuration of the upcoming Dmitroid robot system. Once suitably mutated, tiny Einstein was able to make a few statements and even sing a couple of tunes.

31 May 2014

Floris Stoica-Marcu: GSoC2014 Muon and sudo [Week2]

Hello, This has been a terrific week and a real learning experience for me. I finished packaging both Muon and QApt for Debian; my first two real debian packages, with very different packaging styles! Sune (svuorela), Maximiliano (maxy) and others helped me allot to understand the tools and I thank them very much for their support. While the first part of this second week was all about trying to make a solid package, the second part was me figuring out Policykit and KAuth in order for us to let go (as much as possible) of Kdesudo. I have managed to do a complete turnaround from kdesudo through policykit and now I am working on making an add-repo helper in C++/Qt using KAuth to keep it in line with QApt, in order to have a more uniform codebase. Big thanks to Aleix (apol) that guided me through the different uses of policykit and Kauth. To keep it short, policykit will not be used directly except QApt, in every other case we ll use KAuth. I m very close to finishing the KAuth add-repo helper and that will add improved functionality, as it extends well in what I will be doing next: renouncing specific backend support; The helper will manage how backends add/remove repos, meaning that if you use PackageKit you will no longer be tied to Apt if you want to use Muon! Here is a screenshot of the configure-software button in muon-discovery (finally) working on Debian and launching software-properties-kde:
Muon Software properties And below are some screens of Muon in the wild, running on Debian:
Auth required through policykit

Auth required through policykit

Adding Sources

Adding Sources

I hope you enjoyed this update and stay tuned for the debian package which is currently under review. Floris.

24 May 2014

Wouter Verhelst: kFreeBSD and ZFS

At one particular customer, increasing storage needs require that we add a large file server which should be as fast as possible. In that context, I'm currently evaluating using Debian GNU/kFreeBSD ("Debian," from now on) on ZFS. Not being hampered by a large degree of knowledge on the subject, here's a blog post with things I've learned so far. For context, the system on which we'll be installing will have 64 gigs of RAM, about two dozen SAS disks connected to a RAID controller of which I'm reasonably sure (though not 100% so) that it supports JBOD mode, and a PCIe-attached solid state storage device of several terabytes. If it turns out the RAID controller doesn't support JBOD mode, I'll probably create as many RAID0 devices as possible and hand those over to ZFS as "hard disks", instead; this wouldn't be an ideal solution, but I don't have much of a choice of hard disk attachment, unfortunately. That being said, the system on which I'm testing right now is the latest incantation of samba, an HP ProLiant ML115 server. A system with far more modest hardware specifications, it has 2G of RAM (which isn't really enough for ZFS), a single 160G SATA hard disk, and a dual-core AMD processor of about half a decade ago. And oh yes, no SSD. So for evaluating ZFS performance it's not ideal, but for evaluating Debian and ZFS features, it will do. Anyway, what I've found so far on samba: We'll see what else I learn.

23 May 2014

Steve Kemp: Using a cubox as a media platform.

Somebody recent got in touch offering to mail me a Cubox, in exchange for me experimenting with it and writing about it. In the past I've written book reviews in exchange for receiving free copies, and while I don't want to make a habit of it I don't see a problem providing I'm up-front and honest. So, what is the cubox-i? It's another one of those "small computers", roughly similar to the Raspberry Pi, but with slightly different hardware, and a really neat little case design, as the name suggests it just looks like a tiny two inch cube, only spoiled by the mass of cabling attached to the back. Me? I was cheeky and said I'd have no use for one, unless it was the fancy-model. The hardware comes in 4 different versions, which you can read about on the Cubox-i product page. Ignoring the smaller/cheaper models the fancy version is the CuBox-i4Pro, and this differentiates itself from the Rasberry Pi: I had two uses for this toy; the first was to be a random NAS-box hosting local backups, the second was to be a media-center. In the past I used a Rasberry PI as a media-box, but unfortunately performance was appalling, largely because of the low-spead of the USB WiFi dongle I bought. The video playback would stall at times, even though the hardware could display full HD-output, the network constraints seemed to be a limiting factor. In the end I abandoned it and these days use it sporadically for emulation, and little else. I've been meaning to do something more interesting with it, but never quite got round to it. By contrast the Cubox-i is wonderful at being a media-box. I've exported some shares of MP4/AVI files from my desktop host, via NFS, then downloaded a binary image of the geexbox (XBMC) distribution which I installed onto the MicroSD card via dd. The box boots in about seven seconds, was configured to use WiFi (via "Programs Settings"), and was streaming media in less than two minutes. There is a Debian disitribution available for download from the cubox-i wiki, but sadly it is an ancient snapshot of Jessie from December last year. It did install, but there was no WiFi out of the box. Gunnar Wolf wrote about bootstrapping an image from sources, rather than using a binary snapshot. He's kindly shared the resulting image he built, but again sadly no WiFi support, so for the moment I'm just enjoying the media-suport. In the future I need to decide what to do: I also need to look at running Pure Debian, for obvious reasons, but if I can't use WiFi the machine is no good to me. (The TV is in a different room to the office which contains our Linux hosts.) Either way I've not been excited about new hardware for a while, not since I bought a Logitech Squeezebox, and we're both enjoying watching media on the TV.

17 May 2014

Gunnar Wolf: Guest class: Jose Juan "Kaz" Casimiro ( @brit_kazito ) dissects the Ext4 filesystem module

Yesterday night, we had the opportunity to have for the first time my friend Kaz as a guest in my Operating Systems class. We are about to finish the semester, and he took the opportunity not just to show how the Ext4 filesystem is structured, but how it is implemented in a current Linux release. Kaz took a very different approach from what I do: He did it really hands-on, starting with the explanation on how a hello world module would be created, and then digging in following the code of the ext4 module in Linux 3.14 (and some bits in the general filesystem-related includes). Of course, for a ~2hr session, he did not go into the full details, but did show where the main structures of a filesystem are defined, including a general walkthrough on the general kernel coding style. The class was very enjoyable and clear. We had the bad luck of the projector's lamp burning out at the beginning of the class, but still, you can see in the pictures the students were really into his exposition. I think the exposition did make it through and got the students involved and interested And that makes it really worth it! Now... Sadly, due to a (most probably) human factor, I tried to record this talk but lost most of it :-( I have only the first part, but lost most of the second one. I have some bits recorded by a second camera, but have to check if they make sense by themselves, or do need the whole context. Anyway, I'll be reviewing those bits, and will update this post when I get around to cleaning+fixing+integrating them. Some more photos...
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Video of the first part of Kaz's class26.26 MB
Kaz's slides for the ext4 module40.72 KB

Gunnar Wolf: Guest class: C sar Y ez (@caesarcomptus) talks about virtual memory

Shame on me... I should have uploaded this video a long time ago. I wanted to edit this video to remove pauses, add some in-band indications on who and what it is, and stuff... But after a month, I have not yet got around to do it. On April 23, I invited C sar Y ez to present a talk on virtual memory management to my students (for the Operating Systems class). As always (this is the third time I invite him The previous iteration was on process scheduling, and is on my site as well), he gave a great class. I still have some pending videos to upload from the other guests we had this semester, they should come shortly.
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Video Part 130.43 MB
Video Part 279.23 MB

15 May 2014

Paul Tagliamonte: Linode pv-grub chaining

I've been using Linode since 2010, and many of my friends have heard me talk about how big a fan I am of linode. I've used Debian unstable on all my Linodes, since I often use them as a remote shell for general purpose Debian development. I've found my linodes to be indispensable, and I really love Linode. The Problem Recently, because of my work on Docker, I was forced to stop using the Linode kernel in favor of the stock Debian kernel, since the stock Linode kernel has no aufs support, and the default LVM-based devicemapper backend can be quite a pain. I tried loading in btrfs support, and using that to host the Docker instance backed with btrfs, but it was throwing errors as well. Stuck with unstable backends, I wanted to use the aufs backend, which, dispite problems in aufs internally, is quite stable with Docker (and in general). I started to run through the Linode Library's guide on PV-Grub, but that resulted in a cryptic error with xen not understanding the compression of the kernel. I checked for recent changes to the compresson, and lo, the Debian kernel has been switched to use xz compression in sid. Awesome news, really. XZ compression is awesome, and I've been super impressed with how universally we've adopted it in Debian. Keep it up! However, it appears only a newer pv-grub than the Linode hosts have installed will fix this. After contacting the (ever friendly) Linode support, they were unable to give me a timeline on adding xz support, which would entail upgrading pv-grub. It was quite disapointing news, to be honest. Workarounds were suggested, but I'm not quite happy with them as proper solutions. After asking in #debian-kernel, waldi was able to give me a few pointers, and the following is very inspired by him, the only thing that changed much was config tweaking, which was easy enough. Thanks, Bastian! The Constraints I wanted to maintain a 100% stock configuration from the kernel up. When I upgraded my kernel, I wanted to just work. I didn't want to unpack and repack the kernel, and I didn't want to install software outside main on my system. It had to be 100% Debian and unmodified. The Solution Left unable to run my own kernel directly in the Linode interface, the tact here was to use Linode's old pv-grub to chain-load grub-xen, which loaded a modern kernel. Turns out this works great. Let's start by creating a config for Linode's pv-grub to read and use.
sudo mkdir -p /boot/grub/
Now, since pv-grub is legacy grub, we can write out the following config to chain-load in grub-xen (which is just Grub 2.0, as far as I can tell) to /boot/grub/menu.lst. And to think, I almost forgot all about menu.lst. Almost.
default 1
timeout 3
title grub-xen shim
root (hd0)
kernel /boot/xen-shim
boot
Just like riding a bike! Now, let's install and set up grub-xen to work for us.
sudo apt-get install grub-xen
sudo update-grub
And, let's set the config for the GRUB image we'll create in the next step in the /boot/load.cf file:
configfile (xen/xvda)/boot/grub/grub.cfg
Now, lastly, let's generate the /boot/xen-shim file that we need to boot to:
grub-mkimage --prefix '(xen/xvda)/boot/grub' -c /boot/load.cf -O x86_64-xen /usr/lib/grub/x86_64-xen/*.mod > /boot/xen-shim
Next, change your boot configuration to use pv-grub, and give the machine a kick. Should work great! If you run into issues, use the lish shell to debug it, and let me know what else I should include in this post! Hack on!

14 May 2014

Joey Hess: how I wrote init by accident

I wrote my own init. I didn't mean to, and in the end, it took 2 lines of code. Here's how. Propellor has the nice feature of supporting provisioning of Docker containers. Since Docker normally runs just one command inside the container, I made the command that docker runs be propellor, which runs inside the container and takes care of provisioning it according to its configuration. For example, here's a real live configuration of a container:
        -- Exhibit: kite's 90's website.
        , standardContainer "ancient-kitenet" Stable "amd64"
                & Docker.publish "1994:80"
                & Apt.serviceInstalledRunning "apache2"
                & Git.cloned "root" "git://kitenet-net.branchable.com/" "/var/www"
                        (Just "remotes/origin/old-kitenet.net")
When propellor is run inside this container, it takes care of installing apache, and since the property states apache should be running, it also starts the daemon if necessary. At boot, docker remembers the command that was used to start the container last time, and runs it again. This time, apache is already installed, so propellor simply starts the daemon. This was surprising, but it was just what I wanted too! The only missing bit to make this otherwise entirely free implementation of init work properly was two lines of code:
                void $ async $ job reapzombies
  where
        reapzombies = void $ getAnyProcessStatus True False
Propellor-as-init also starts up a simple equalivilant of rsh on a named pipe (for communication between the propellor inside and outside the container), and also runs a root login shell (so the user can attach to the container and administer it). Also, running a compiled program from the host system inside a container, which might use a different distribution or architecture was an interesting challenge (solved using the method described in completely linux distribution-independent packaging). So it wasn't entirely trivial, but as far as init goes, it's probably one of the simpler implementations out there. I know that there are various other solutions on the space of an init for Docker -- personally I'd rather the host's systemd integrated with it so I could see the status of the container's daemons in systemctl status. If that does happen, perhaps I'll eventually be able to remove 2 lines of code from propellor.

9 May 2014

Rhonda D'Vine: Rhonda's Free Hugging Guidelines

Recently I was wearing my Free Hugs shirt to different Free Software meetings, and I came up with the idea if we are advocating the Free in Software specificly, why not come up with Free Hugging Guidelines, too. So here they are, from now on considered to be named the RFHG.
  1. Free Redistribution Your hugs may not restrict any party from passing on the hugs they received from you.
  2. Source Code The hugs must be possible to be perceived and understandable in complete. You are not allowed to use any special techniques that can not be perceived.
  3. Derived Works Your hugs must be allowed to be modified, and must allow the modified forms of your hugs to be distributed under the same terms as they received them.
  4. Integrity of The Author's Source Code While you are allowed to pass on the hugs in modified form, you are not allowed to modify the DNA of the original person you received the hugs from. Genetic modification is out of the scope of the RFHG.
  5. No Discrimination Against Persons or Groups While we acknowledge that you might not feel willing to hug everyone, you must apply rules that do not distinquish by rules which would violate The Universal Declaration of Human Rights. Furthermore, you have the right to not hug a person if you are not in the mood for it. Please refrain from wearing any Free Hugs markers at those times though.
  6. No Discrimination Against Fields of Endeavor The hugs can not be restricted to be used in a specific field of endeavor. For example, you may not restrict the hugs from being passed on only in times of sorrow.
  7. Distribution of Hugs The rights attached to the hugs must apply to all to whom the hugs are redistributed without the need for execution of an additional license by those parties.
  8. Hugs Must Not Be Specific to Rhonda The rights attached to the hugs must not depend on the hugs being related to Rhonda. If the hugs are extracted from Rhonda and used or distributed without Rhonda nearby but otherwise within the terms of the hug's permissions, all parties to whom the hugs are distributed should have the same rights as those that are granted in conjunction with Rhonda.
  9. Hugs Must Not Contaminate Other People If you are contagious (e.g. got the flu, or worse) you have to apply appropriate counter measures to not transfer your illness with your hugs.
  10. Example Hugs This Group Hug modification and of course the Free Hugs Campaign are great examples of what we consider Free.
One last note: If you feel like it you don't have to wait until I wear my Free Hugs shirt again. I am fine with receiving (or giving) hugs like almost always. Surprise me. I at least know then that you read the RFHG. :) Like always, enjoy!

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5 May 2014

Vincent Bernat: Dashkiosk: manage dashboards on multiple displays

Dashkiosk is a solution to manage dashboards on multiple displays. It comes in four parts:
  1. A server will manage the screens by sending URL to be displayed. A web interface enables an administrator to configure groups of dashboards and attach them to a set of displays.
  2. A receiver runs in a browser attached to each screen. On start, it contacts the server and waits for the URL to display.
  3. An Android application provides a simple fullscreen webview to display the receiver.
  4. A Chromecast custom receiver which will run the regular receiver to display dashboards using Google Chromecast devices. The server is able to drive Chromecast devices through nodecastor, a reimplementation of the sender API.
For a demo, have a look at the following video (it is also available as an Ogg Theora video).

Gunnar Wolf: Correction for @osupiita

I was invited to give a talk at a local conference, OS-UPIITA. I have been invited to this conference before, and will gladly be there again. But I was recently pointed at the invitation poster they are distributing (which I reproduce here for your convenience) And I must make a couple of corrections here:
  1. First and foremost: I don't want to trick anybody. I am not the Director of Debian Mexico. In fact, Debian Mexico does not exist. I am just a humble Debian Developer.
  2. I accept the conference title, because that's what they requested from me. I'm trying to come up with a coherent exposition, but whoever knows me must be perfectly aware that I don't know (nor really care about) how to make money with Free Software. I have lived all of my professional life thanks to Free Software, but I'm against the entrepenurial culture. I will talk about my vision, of course, so if you want to hear me rant, you are invited to join us ;-)
  3. I specifically asked the organizing committee by mid-April, when they gave me the talk title, to replace "Open Source" with "Free Software" in my talk. Even though the conference is called "OS UPIITA" (as it is the Open Source conference in the UPIITA unit of Instituto Polit cnico Nacional), I cannot identify with the Open Source monkier. And if we are talking about a deeply ideological issue, which is the case here, I request to use the name I can relate with. For my talk only, of course.
</rant> But anyway, I will be very happy to be there, and believe me, am working to come up with a good talk. OS-UPIITA friends: Please correct your online banners carrying this wrong data. [update] OS-UPIITA changed the poster! I'm just keeping this one for the memory ;-) [update 2] I was there, and gave the talk. And it was even a success, yay! \o/ Care to see it? Here is the presented material.
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22 April 2014

Axel Beckert: GNU Screen 4.2.0 in Debian Experimental

About a month ago, on 20th of March, GNU Screen had its 27th anniversary. A few days ago, Amadeusz S awi ski, GNU Screen s new primary upstream maintainer, released the status quo of Screen development as version 4.2.0 (probably to distinguish it from all those 4.1.0 labeled development snapshots floating around in most Linux distributions nowadays). I did something similar and uploaded the status quo of Debian s screen package in git as 4.1.0~20120320gitdb59704-10 to Debian Sid shortly afterwards. That upload should hit Jessie soon, too, resolving the following two issues also in Testing: That way I could decouple these packaging fixes/features from the new upstream release which I uploaded to Debian Experimental for now. Testers for the 4.2.0-1 package are very welcome! Oh, and by the way, that upstream comment (or ArchLinux s according announcement) about broken backwards compatibility with attaching to running sessions started with older Screen releases doesn t affected Debian since that has been fixed in Debian already with the package which is in Wheezy. (Thanks again Julien Cristau for the patch back then!) While there are bigger long-term plans at upstream, Amadeusz is already working on the next 4.x release (probably named 4.2.1) which will likely incorporate some of the patches floating around in the Linux distributions packages. At least SuSE and Debian offered their patches explicitly for upstream inclusion. So far already two patches found in the Debian packages have been obsoleted by upstream git commits after the 4.2.0 release. Yay!

Bits from Debian: Debian welcomes its 2014 GSoC students!

We're excited to announce that 19 students have been selected to work with Debian during the Google Summer of Code this year! Here is the list of accepted students and projects: As always, you will be able to follow their progress on the SoC coordination mailing-list Congratulations to all the students and let's make sure we all have an amazing summer!

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