Search Results: "ema"

3 March 2013

Philipp Kern: git-annex: encrypted remotes

Due to the data loss I blogged about, I had to reverse engineer the encryption used by git-annex for its encrypted special remotes. The file system on which the content lived has a bullet hole of 8 GB in it, which was helpfully discarded by pvmove. It's pretty unhappy about that fact, parts of the git repository are unusable and directories cannot be accessed anymore. git-annex cannot possibly run anymore.

However, I was still able to access the git-annex branch within said git repository (using porcelain). This branch contains a file called remote.log which contains the keys of the special remotes. There's one per remote, encrypted to a GPG key of your choice and all files within that remote are encrypted with the same symmetric key.

One small detail stopped me from getting the decryption right the first time, though. It seems that git-annex uses randomness generated by GPG and armored into base64. In my na vet I spotted the base64 and decoded it. Instead it's used verbatim: the first 256 bytes as HMAC key (which reduces randomness to 192 bytes) and the remaining bytes for the symmetric key used by GPG (which will do another key derivation for CAST5 with it). A bug about that just hit the git-annex wiki.

With that knowledge in mind I wrote a little tool that's able to generate encrypted content keys from the plain ones used in the symlinks. That helps you to locate the file in the encrypted remote. Fetch it and then use the tool to decrypt the file in question with the right key.

The lesson: Really backup the git repository used with git-annex and especially remote.log. I'm now missing most of the metadata but for some more important files it's luckily still present. Recovery of the file content does not depend on it if you can deduce the filename from the content. If you have many little files it might be a bit futile without it, though.

Gregor Herrmann: DPL game

when francesca started her DPL game, I also started thinking about people I'd like to encourage to stand as a DPL candidate. unfortunately my initial "short list" contained 18 names, which doesn't fit the game's rules very well. after waiting a bit, 9 of them were mentioned by others already, so I can leave them out here (which also means no public hug, sorry, please complain to the inventor of the game!). from the remaining 9, I've now chosen my Fantastic Four (in alphabtic order of first names): in my opinion, the DPL task is mostly about managing, & those four people are in my experience all very good at organising projects & dealing with people, & are therefore well suited for this task. let's see if they feel motivated to take on the challenge! (the nomination period has already started, so don't hestitate!)

Petter Reinholdtsen: Frikanalen - Complete TV station organised using the web

Do you want to set up your own TV station, schedule videos and broadcast them on the air? Using free software? With video on demand support using free and open standards? Included a web based video stream as well? And administrate it all in your web browser from anywhere in the world? A few years now the Norwegian public access TV-channel Frikanalen have been building a system to do just this. The source code for the solution is licensed using the GNU LGPL, and available from github. The idea is simple. You upload a video file over the web, and attach meta information to the file. You select a time slot in the program schedule, and when the time come it is played on the air and in the web stream. It is also made available in a video on demand solution for anyone to see it also outside its scheduled time. All you need to run a TV station - using your web browser. There are several parts to this web based solution. I'll mention the three most important ones. The first part is the database of videos and the schedule. This is written in Django and include a REST API. The current database is SQLite, but the plan is to migrate it to PostgreSQL. At the moment this system can be tested on beta.frikanalen.tv. The second part is the video playout, taking the schedule information from the database and providing a video stream to broadcast. This is done using CasparCG from SVT and Media Lovin' Toolkit. Video signal distribution is handled using Open Broadcast Encoder. The third part is the converter, handling the transformation of uploaded video files to a format useful for broadcasting, streaming and video on demand. It is still very much work in progress, so it is not yet decided what it will end up using. Note that the source of the latter two parts are not yet pushed to github. The lead author want to clean them up a bit more first. The development is coordinated on the #frikanalen IRC channel (irc.freenode.net), and discussed on the frikanalen mailing list. The lead developer is Benjamin Bruheim (phed on IRC). Anyone is welcome to participate in the development.

2 March 2013

Raphaël Hertzog: My Free Software Activities in February 2013

This is my monthly summary of my free software related activities. If you re among the people who made a donation to support my work (78.31 , thanks everybody!), then you can learn how I spent your money. Otherwise it s just an interesting status update on my various projects. Debian packaging I wanted to update publican to the latest upstream release but I stopped after a few hours of work during which I filed two bugs that a modicum of testing should have caught before release. So I decided to wait for the next minor release. I uploaded python-django 1.4.4 and 1.4.5, new upstream maintenance and security releases which thus went into wheezy. I also prepared a stable update of Django (1.2.3-3+squeeze5) which required me to backport the last 2 sets of security patches. I uploaded a new revision of wordpress to fix a problem with TinyMCE (#700289) and to update/add many translation files (#697208). Bug reporting and misc fixes Live-build issue. I experienced some intermittent failures when building HDD live images with live-build on armel. Daniel Baumann directed me to the problematic piece of code (the oversizing of the image size was not enough) so I committed a small fix by increasing the oversizing factor to 6%. Live-config issue. I also reported another issue that I diagnosed in live-config (#701788), namely that the script which setups sudo was failing when the default user is root. git-buildpackage issue. I filed #700411 after noticing that git-import-orig imported the debian directory provided by upstream. Those directories are not used with 3.0 (quilt) source package and their presence in the upstream branch is thus harmful: any change to the upstream debian directory will result in conflicts when you merge a new upstream release in your packaging branch. rubygems integration. Later I had to package a bunch of ruby applications that were using Bundler and I wanted to reuse as many packaged ruby modules that I could. But for this, those modules had to provide the required rubygems meta-information. I filed #700419 to request those on rake-compiler and with the help of C dric Boutillier (and others on #debian-ruby), we identified a bunch of ruby modules which could get those with a simple recompilation. I filed bin-nmu requests in #700605. Misc bugs. simple-cdd offers to select profiles to install but I noticed that the associated debconf template was not translated (#700915). The startup scripts (provided by initscripts) in charge of activating the swap are supposed to handle a noswap kernel command line option to disable swap. In #701301, I reported that the option was not working correctly if quiet was present first in the command line due to spurious break statements. Debian France Administrative work. We were late for some legal procedures so I wrote the report of the last general assembly and sent it to the Tribunal d instance of Sarreguemines to record the changes in the administrative board. I also completed the special register of the association, it s a notebook that is legally required and that must document any important change in the governance structure of the association (new members of the board, headquarters change, new bylaws, etc.). Galette developments. Debian France is funding a few enhancements to the Galette free software that we re using to manage the association. I am in touch with the Galette developer to answer his questions and ensure that his work will meet our needs. Librement I have been looking for talented developers who have a genuine interest in my Librement project. I want to fund the initial development of the project but I don t have the means to fund it entirely. So I really wanted to find developers who would find an interest beside the money that I would pay. I got in touch with the team of developers from Scopyleft and they look like very good candidates. But they re heavy users of the Scrum development method and asked me to play the role of product owner . So I started to describe the project with user stories (i.e. create the backlog in the Scrum jargon), you can have a look at them here on trello.com. If you re interested by the topic of free software funding, feel free to review and to send me your comments. My goal is clearly to have a minimal viable product with the first iteration(s) that I fund and then use the platform itself to fund further developments of the project. Thanks See you next month for a new summary of my activities.

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Paul Tagliamonte: Firehose - wanna hack?

As folks know, I ve been hacking on Firehose. I ve been debating doing some work to modify / extend / replace DACA, and I could use some help writing new wrappers around static check code, so, who wants to hack? Any UI folks? I could use a UI to view Firehose data, something spiffy and colorful. Hackers? Send in some wrappers for your favorite static checking code. Send in pull requests or email me with a pointer to the repo :) Hack on, folks!

28 February 2013

Erich Schubert: ELKI data mining in 2013

ELKI, the data mining framework I use for all my research, is coming along nicely, and will see continued progress in 2013. The next release is scheduled for SIGMOD 2013, where we will be presenting the novel 3D parallel coordinates visualization we recently developed. This release will bear the version number 0.6.0.
Version 0.5.5 of ELKI is in Debian unstable since december (Version 0.5.0 will be in the next stable release) and Ubuntu raring. The packaged installation can share the dependencies with other Debian packages, so they are smaller than the download from the ELKI web site.
If you are developing cluster analysis or outlier detection algorithm, I would love to see them contributed to ELKI. If I get a clean and well-integrated code by mid june, your algorithm could be included in the next release, too. Publishing your algorithms in source code in a larger framework such as ELKI will often give you more citations. Because it is easier to compare with your algorithm then and to try it on new problems. And, well, citations counts are a measure that administration loves to judge researchers ...
So what else is happening with ELKI:
  • The new book "Outlier Analysis" by C. C. Aggarwal mentions ELKI for visual evaluation of outlier results as well as in the "Resources for the Practioner" section and cites around 10 publications closely related to ELKI.
  • Some classes for color feature extraction of ELKI have been contributed to jFeatureLib, a Java library for feature detection in image data.
  • I'd love to participate in the Google Summer of Code, but I need a contact at Google to "vouch" for the project, otherwise it is hard to get in. I've been sending a couple of emails, but so far have not heard back much yet.
  • As the performance of SVG/Batik is not too good, I'd like to see more OpenGL based visualizations. This could also lead to an Android based version for use on tablets.
  • As I'm not an UI guy, I would love to have someone make a fancier UI that still exposes all the rich functions we have. The current UI is essentially an automatically generated command line builder - which is nice, as new functionality shows up without the need to modify UI code. It's good for experienced users like me, but hard for beginners to get started.
  • I'd love to see integration of ELKI with e.g. OpenRefine / Google Refine to make it easier to do appropriate data cleaning and preprocessing
  • There is work underway for a distributed version running on Hadoop/YARN.

Daniel Kahn Gillmor: Make a Woolly Mammoth (thanks, inkscape!)

I feel like i've done a lot of blogging recently about failing to do things with proprietary software. That's annoying. This post is about something i made successfully with free software (and some non-software crafting): I made a Woolly Mammoth for my nephew!I documented the pattern (with pictures!) that i came up with using Inkscape (and used markdown, pandoc, emacs, pdftk, and other free software in the process). i've also published the source for the pattern via git if you want to modify it: 
git clone git://lair.fifthhorseman.net/~dkg/woolly
Writing up the documentation makes me realize that i don't know of any software tools designed specifically for facilitating fabric/craft construction. Some interesting software ideas: Anyone have any ideas?Tags: brainstorming, crafting, inkscape

27 February 2013

Neil McGovern: Let s get physical

Two recent announcements have been made about how it's viewed that people should interact with each other. Both, in my opinion, are misguided. Firstly, Yahoo's chief executive, Marissa Mayer has announced that she's banning staff from remote working. The idea behind this announcement is simple - that "some of the best decisions and insights come from hallway and cafeteria discussions, meeting new people, and impromptu team meetings". This is absolutely spot on, but the next sentence in the leaked internal memo is more problematic: "Speed and quality are often sacrificed when we work from home".
Don't get me wrong, working remotely has some special challenges, but they are by no means insurmountable. There's lots of tips for people working remotely which will turn into a future blog post at some point (I'm running an internal training about how to do it in a couple of weeks), but three simple rules are stay connected, set a routine and take care of yourself. The second decision is one by Ubuntu to move Ubuntu Developer Summits to a purely online meeting, ditching the physical meeting. This misses the point of conferences. If we simply wanted to listen to talks and presentations, why meet up at all? Webcasts have been around for the last 20 years, and yet conferences still exist. The most important part of a conference isn't the talks, it's the "hallway track" - it's the ability for people to meet up, chat and socialise. Be this an impromptu meeting in the corridor, or over a few nice beers. Without this component, why schedule a time at all? Simply publish a list of talks over the coming 3 months, and anyone can pick the best time for them to attend. At Collabora, many of our engineers work remotely. One of the perks we offer is the ability to attend conferences, and to "touch base" and visit and work from one of the offices. It is important to recognise the importance of collaboration physically and it shouldn't be discounted the way Ubuntu has done. But it should not be seen as a silver bullet to an organisation, like Yahoo seem to be implying. Both extremes are wrong, and a balance must be struck to ensure the best outcome for productivity and innovation. (Title from an iconic 80s song)

26 February 2013

Ingo Juergensmann: Xen problems with VMs on 2.6.32-5-xen-amd64?

On Saturday there were some updates for Squeeze/Stable, for example a new/updated version of Xen hypervisor and kernels were downloaded and installed: 
gate:~# dir /var/cache/apt/archives/
base-files_6.0squeeze7_amd64.deb                 libxenstore3.0_4.0.1-5.6_amd64.deb
bind9-host_1%3a9.7.3.dfsg-1~squeeze9_amd64.deb   linux-base_2.6.32-48_all.deb
dbus_1.2.24-4+squeeze2_amd64.deb                 linux-image-2.6.32-5-amd64_2.6.32-48_amd64.deb
dbus-x11_1.2.24-4+squeeze2_amd64.deb             linux-image-2.6.32-5-xen-amd64_2.6.32-48_amd64.deb
firmware-linux-free_2.6.32-48_all.deb            lock
gzip_1.3.12-9+squeeze1_amd64.deb                 openssh-client_1%3a5.5p1-6+squeeze3_amd64.deb
host_1%3a9.7.3.dfsg-1~squeeze9_all.deb           openssh-server_1%3a5.5p1-6+squeeze3_amd64.deb
libbind9-60_1%3a9.7.3.dfsg-1~squeeze9_amd64.deb  openssl_0.9.8o-4squeeze14_amd64.deb
libcups2_1.4.4-7+squeeze3_amd64.deb              partial
libdbus-1-3_1.2.24-4+squeeze2_amd64.deb          perl_5.10.1-17squeeze5_amd64.deb
libdbus-glib-1-2_0.88-2.1+squeeze1_amd64.deb     perl-base_5.10.1-17squeeze5_amd64.deb
libdns69_1%3a9.7.3.dfsg-1~squeeze9_amd64.deb     perl-modules_5.10.1-17squeeze5_all.deb
libisc62_1%3a9.7.3.dfsg-1~squeeze9_amd64.deb     ssh_1%3a5.5p1-6+squeeze3_all.deb
libisccc60_1%3a9.7.3.dfsg-1~squeeze9_amd64.deb   tzdata_2012g-0squeeze1_all.deb
libisccfg62_1%3a9.7.3.dfsg-1~squeeze9_amd64.deb  xen-hypervisor-4.0-amd64_4.0.1-5.6_amd64.deb
libldap-2.4-2_2.4.23-7.3_amd64.deb               xen-linux-system-2.6.32-5-xen-amd64_2.6.32-48_amd64.deb
liblwres60_1%3a9.7.3.dfsg-1~squeeze9_amd64.deb   xenstore-utils_4.0.1-5.6_amd64.deb
libperl5.10_5.10.1-17squeeze5_amd64.deb          xen-utils-4.0_4.0.1-5.6_amd64.deb
libssl0.9.8_0.9.8o-4squeeze14_amd64.deb
Unfortunately this update appears to be problematic on my Xen hosting server. This night it happened the second time that some of the virtual network interfaces disappeared or turned out to be non-working. For example I have two VMs: one running the webserver and one running the databases. Between these two VMs there's a bridge on the dom0 and both VMs have a VIF to that (internal) bridge. What happens is that this bridge becomes inaccessible from within the webserver VM. Sadly there's not much to see in the log files. I just spotted this on dom0:
Feb 26 01:01:29 gate kernel: [12697.907512] vif3.1: Frag is bigger than frame.
Feb 26 01:01:29 gate kernel: [12697.907550] vif3.1: fatal error; disabling device
Feb 26 01:01:29 gate kernel: [12697.919921] xenbr1: port 3(vif3.1) entering disabled state
Feb 26 01:22:00 gate kernel: [13928.644888] vif2.1: Frag is bigger than frame.
Feb 26 01:22:00 gate kernel: [13928.644920] vif2.1: fatal error; disabling device
Feb 26 01:22:00 gate kernel: [13928.663571] xenbr1: port 2(vif2.1) entering disabled state
Feb 26 01:40:44 gate kernel: [15052.629280] vif7.1: Frag is bigger than frame.
Feb 26 01:40:44 gate kernel: [15052.629314] vif7.1: fatal error; disabling device
Feb 26 01:40:44 gate kernel: [15052.641725] xenbr1: port 6(vif7.1) entering disabled state
This corresponds to the number of VMs having lost their internal connection to the bridge. On the webserver VM I see this output:
Feb 26 01:59:01 vserv1 kernel: [16113.539767] IPv6: sending pkt_too_big to self
Feb 26 01:59:01 vserv1 kernel: [16113.539794] IPv6: sending pkt_too_big to self
Feb 26 02:30:54 vserv1 kernel: [18026.407517] IPv6: sending pkt_too_big to self
Feb 26 02:30:54 vserv1 kernel: [18026.407546] IPv6: sending pkt_too_big to self
Feb 26 02:30:54 vserv1 kernel: [18026.434761] IPv6: sending pkt_too_big to self
Feb 26 02:30:54 vserv1 kernel: [18026.434787] IPv6: sending pkt_too_big to self
Feb 26 03:39:16 vserv1 kernel: [22128.768214] IPv6: sending pkt_too_big to self
Feb 26 03:39:16 vserv1 kernel: [22128.768240] IPv6: sending pkt_too_big to self
Feb 26 04:39:51 vserv1 kernel: [25764.250170] IPv6: sending pkt_too_big to self
Feb 26 04:39:51 vserv1 kernel: [25764.250196] IPv6: sending pkt_too_big to self
Rebooting the VMs will result in a non-working VM as it will get paused on creation and Xen scripts complain about not working hotplug scripts and Xen logs shows this: 
[2013-02-25 13:06:34 5470] DEBUG (XendDomainInfo:101)
XendDomainInfo.create(['vm', ['name', 'vserv1'], ['memory', '2048'],
['on_poweroff', 'destroy'], ['on_reboot', 'restart'], ['on_crash',
'restart'], ['on_xend_start', 'ignore'], ['on_xend_stop', 'ignore'],
['vcpus', '2'], ['oos', 1], ['bootloader', '/usr/lib/xen-4.0/bin/pygrub'],
['bootloader_args', ''], ['image', ['linux', ['root', '/dev/xvdb '],
['videoram', 4], ['tsc_mode', 0], ['nomigrate', 0]]], ['s3_integrity', 1],
['device', ['vbd', ['uname', 'phy:/dev/lv/vserv1-boot'], ['dev', 'xvda'],
['mode', 'w']]], ['device', ['vbd', ['uname', 'phy:/dev/lv/vserv1-disk'],
['dev', 'xvdb'], ['mode', 'w']]], ['device', ['vbd', ['uname',
'phy:/dev/lv/vserv1-swap'], ['dev', 'xvdc'], ['mode', 'w']]], ['device',
['vbd', ['uname', 'phy:/dev/lv/vserv1mirror'], ['dev', 'xvdd'], ['mode',
'w']]]])
[2013-02-25 13:06:34 5470] DEBUG (XendDomainInfo:2508)
XendDomainInfo.constructDomain
[2013-02-25 13:06:34 5470] DEBUG (balloon:220) Balloon: 2100000 KiB free;
need 16384; done.
[2013-02-25 13:06:34 5470] DEBUG (XendDomain:464) Adding Domain: 39
[2013-02-25 13:06:34 5470] DEBUG (XendDomainInfo:2818)
XendDomainInfo.initDomain: 39 256
[2013-02-25 13:06:34 5781] DEBUG (XendBootloader:113) Launching bootloader
as ['/usr/lib/xen-4.0/bin/pygrub', '--args=root=/dev/xvdb  ',
'--output=/var/run/xend/boot/xenbl.6040', '/dev/lv/vserv1-boot'].
[2013-02-25 13:06:39 5470] DEBUG (XendDomainInfo:2845)
_initDomain:shadow_memory=0x0, memory_static_max=0x80000000,
memory_static_min=0x0.
[2013-02-25 13:06:39 5470] INFO (image:182) buildDomain os=linux dom=39
vcpus=2
[2013-02-25 13:06:39 5470] DEBUG (image:721) domid	    = 39
[2013-02-25 13:06:39 5470] DEBUG (image:722) memsize	    = 2048
[2013-02-25 13:06:39 5470] DEBUG (image:723) image	    =
/var/run/xend/boot/boot_kernel.xj7W_t
[2013-02-25 13:06:39 5470] DEBUG (image:724) store_evtchn   = 1
[2013-02-25 13:06:39 5470] DEBUG (image:725) console_evtchn = 2
[2013-02-25 13:06:39 5470] DEBUG (image:726) cmdline	    =
root=UUID=ed71a39f-fd2e-4035-8557-493686baa151 ro root=/dev/xvdb
[2013-02-25 13:06:39 5470] DEBUG (image:727) ramdisk	    =
/var/run/xend/boot/boot_ramdisk.QavuAo
[2013-02-25 13:06:39 5470] DEBUG (image:728) vcpus	    = 2
[2013-02-25 13:06:39 5470] DEBUG (image:729) features	    =
[2013-02-25 13:06:39 5470] DEBUG (image:730) flags	    = 0
[2013-02-25 13:06:39 5470] DEBUG (image:731) superpages     = 0
[2013-02-25 13:06:40 5470] INFO (XendDomainInfo:2367) createDevice: vbd :
 'uuid': '04d99772-cf27-aecf-2d1b-c73eaf657410', 'bootable': 1, 'driver':
'paravirtualised', 'dev': 'xvda', 'uname': 'phy:/dev/lv/vserv1-boot',
'mode': 'w' 
[2013-02-25 13:06:40 5470] DEBUG (DevController:95) DevController: writing
 'virtual-device': '51712', 'device-type': 'disk', 'protocol':
'x86_64-abi', 'backend-id': '0', 'state': '1', 'backend':
'/local/domain/0/backend/vbd/39/51712'  to
/local/domain/39/device/vbd/51712.
[2013-02-25 13:06:40 5470] DEBUG (DevController:97) DevController: writing
 'domain': 'vserv1', 'frontend': '/local/domain/39/device/vbd/51712',
'uuid': '04d99772-cf27-aecf-2d1b-c73eaf657410', 'bootable': '1', 'dev':
'xvda', 'state': '1', 'params': '/dev/lv/vserv1-boot', 'mode': 'w',
'online': '1', 'frontend-id': '39', 'type': 'phy'  to
/local/domain/0/backend/vbd/39/51712.
[2013-02-25 13:06:40 5470] INFO (XendDomainInfo:2367) createDevice: vbd :
 'uuid': 'e46cb89f-3e54-41d2-53bd-759ed6c690d2', 'bootable': 0, 'driver':
'paravirtualised', 'dev': 'xvdb', 'uname': 'phy:/dev/lv/vserv1-disk',
'mode': 'w' 
[2013-02-25 13:06:40 5470] DEBUG (DevController:95) DevController: writing
 'virtual-device': '51728', 'device-type': 'disk', 'protocol':
'x86_64-abi', 'backend-id': '0', 'state': '1', 'backend':
'/local/domain/0/backend/vbd/39/51728'  to
/local/domain/39/device/vbd/51728.
[2013-02-25 13:06:40 5470] DEBUG (DevController:97) DevController: writing
 'domain': 'vserv1', 'frontend': '/local/domain/39/device/vbd/51728',
'uuid': 'e46cb89f-3e54-41d2-53bd-759ed6c690d2', 'bootable': '0', 'dev':
'xvdb', 'state': '1', 'params': '/dev/lv/vserv1-disk', 'mode': 'w',
'online': '1', 'frontend-id': '39', 'type': 'phy'  to
/local/domain/0/backend/vbd/39/51728.
[2013-02-25 13:06:40 5470] INFO (XendDomainInfo:2367) createDevice: vbd :
 'uuid': 'e2d61860-7448-1843-3935-6b63c5d2878e', 'bootable': 0, 'driver':
'paravirtualised', 'dev': 'xvdc', 'uname': 'phy:/dev/lv/vserv1-swap',
'mode': 'w' 
[2013-02-25 13:06:40 5470] DEBUG (DevController:95) DevController: writing
 'virtual-device': '51744', 'device-type': 'disk', 'protocol':
'x86_64-abi', 'backend-id': '0', 'state': '1', 'backend':
'/local/domain/0/backend/vbd/39/51744'  to
/local/domain/39/device/vbd/51744.
[2013-02-25 13:06:40 5470] DEBUG (DevController:97) DevController: writing
 'domain': 'vserv1', 'frontend': '/local/domain/39/device/vbd/51744',
'uuid': 'e2d61860-7448-1843-3935-6b63c5d2878e', 'bootable': '0', 'dev':
'xvdc', 'state': '1', 'params': '/dev/lv/vserv1-swap', 'mode': 'w',
'online': '1', 'frontend-id': '39', 'type': 'phy'  to
/local/domain/0/backend/vbd/39/51744.
[2013-02-25 13:06:40 5470] INFO (XendDomainInfo:2367) createDevice: vbd :
 'uuid': 'd314a46e-1ce9-0e8d-b009-3f08e29735f5', 'bootable': 0, 'driver':
'paravirtualised', 'dev': 'xvdd', 'uname': 'phy:/dev/lv/vserv1mirror',
'mode': 'w' 
[2013-02-25 13:06:40 5470] DEBUG (DevController:95) DevController: writing
 'virtual-device': '51760', 'device-type': 'disk', 'protocol':
'x86_64-abi', 'backend-id': '0', 'state': '1', 'backend':
'/local/domain/0/backend/vbd/39/51760'  to
/local/domain/39/device/vbd/51760.
[2013-02-25 13:06:40 5470] DEBUG (DevController:97) DevController: writing
 'domain': 'vserv1', 'frontend': '/local/domain/39/device/vbd/51760',
'uuid': 'd314a46e-1ce9-0e8d-b009-3f08e29735f5', 'bootable': '0', 'dev':
'xvdd', 'state': '1', 'params': '/dev/lv/vserv1mirror', 'mode': 'w',
'online': '1', 'frontend-id': '39', 'type': 'phy'  to
/local/domain/0/backend/vbd/39/51760.
[2013-02-25 13:06:40 5470] DEBUG (XendDomainInfo:3400) Storing VM details:
 'on_xend_stop': 'ignore', 'shadow_memory': '0', 'uuid':
'04541225-6d3c-3cae-a4c4-0b6d4ccfac7a', 'on_reboot': 'restart',
'start_time': '1361794000.37', 'on_poweroff': 'destroy', 'bootloader_args':
'', 'on_xend_start': 'ignore', 'on_crash': 'restart', 'xend/restart_count':
'0', 'vcpus': '2', 'vcpu_avail': '3', 'bootloader':
'/usr/lib/xen-4.0/bin/pygrub', 'image': "(linux (kernel ) (args
'root=/dev/xvdb  ') (superpages 0) (tsc_mode 0) (videoram 4) (pci ())
(nomigrate 0) (notes (HV_START_LOW 18446603336221196288) (FEATURES
'!writable_page_tables pae_pgdir_above_4gb') (VIRT_BASE
18446744071562067968) (GUEST_VERSION 2.6) (PADDR_OFFSET 0) (GUEST_OS linux)
(HYPERCALL_PAGE 18446744071578882048) (LOADER generic) (SUSPEND_CANCEL 1)
(PAE_MODE yes) (ENTRY 18446744071584289280) (XEN_VERSION xen-3.0)))",
'name': 'vserv1' 
[2013-02-25 13:06:40 5470] DEBUG (XendDomainInfo:1804) Storing domain
details:  'console/ring-ref': '2143834', 'image/entry':
'18446744071584289280', 'console/port': '2', 'store/ring-ref': '2143835',
'image/loader': 'generic', 'vm':
'/vm/04541225-6d3c-3cae-a4c4-0b6d4ccfac7a',
'control/platform-feature-multiprocessor-suspend': '1',
'image/hv-start-low': '18446603336221196288', 'image/guest-os': 'linux',
'cpu/1/availability': 'online', 'image/virt-base': '18446744071562067968',
'memory/target': '2097152', 'image/guest-version': '2.6', 'image/pae-mode':
'yes', 'description': '', 'console/limit': '1048576', 'image/paddr-offset':
'0', 'image/hypercall-page': '18446744071578882048',
'image/suspend-cancel': '1', 'cpu/0/availability': 'online',
'image/features/pae-pgdir-above-4gb': '1',
'image/features/writable-page-tables': '0', 'console/type': 'xenconsoled',
'name': 'vserv1', 'domid': '39', 'image/xen-version': 'xen-3.0',
'store/port': '1' 
[2013-02-25 13:06:40 5470] DEBUG (DevController:95) DevController: writing
 'protocol': 'x86_64-abi', 'state': '1', 'backend-id': '0', 'backend':
'/local/domain/0/backend/console/39/0'  to
/local/domain/39/device/console/0.
[2013-02-25 13:06:40 5470] DEBUG (DevController:97) DevController: writing
 'domain': 'vserv1', 'frontend': '/local/domain/39/device/console/0',
'uuid': 'c8819aed-c78f-02b8-0ef7-1600abd15add', 'frontend-id': '39',
'state': '1', 'location': '2', 'online': '1', 'protocol': 'vt100'  to
/local/domain/0/backend/console/39/0.
[2013-02-25 13:06:40 5470] DEBUG (XendDomainInfo:1891)
XendDomainInfo.handleShutdownWatch
[2013-02-25 13:06:40 5470] DEBUG (DevController:139) Waiting for devices
vif2.
[2013-02-25 13:06:40 5470] DEBUG (DevController:139) Waiting for devices
vif.
[2013-02-25 13:06:40 5470] DEBUG (DevController:139) Waiting for devices
vscsi.
[2013-02-25 13:06:40 5470] DEBUG (DevController:139) Waiting for devices
vbd.
[2013-02-25 13:06:40 5470] DEBUG (DevController:144) Waiting for 51712.
[2013-02-25 13:06:40 5470] DEBUG (DevController:628) hotplugStatusCallback
/local/domain/0/backend/vbd/39/51712/hotplug-status.
From my point of view, either Xen hypervisor or the kernel seems to be broken, but it's hard to tell for me. Maybe it would be easier to update the system from Squeeze to Wheezy and get rid off this problem that way? On the other hand this would solve the problem. Are there any other people experiencing problems with that latest update of Xen and kernel? UPDATE: Bug #701744 filed. UPDATE 2: Downgrading kernel and hypervisor on dom0 to the following packages from snapshot.debian.org seems to have solved that problem.
  • xen-hypervisor-4.0-amd64_4.0.1-5.4_amd64.deb
  • linux-image-2.6.32-5-xen-amd64_2.6.32-46_amd64.deb
Note that I haven't tested yet with the newest kernel update from DSA-2632-1. UPDATE 3: After running with older versions of hypervisor and kernel I now have upgraded the hypervisor to xen-hypervisor-4.0-amd64_4.0.1-5.6_amd64.deb and rebooted. Let's see whether it's running stable or not. If not it's the hypervisor, if yes, it's the kernel. UPDATE 4: apparently it's the kernel which is buggy. And the kernel from DSA-2632-1 is affected as well. So, the current workaround is to downgrad to linux-image-2.6.32-5-xen-amd64_2.6.32-46_amd64.deb.
Kategorie:
Debian
Tags:
Xen
Debian
Software
Bug
Server

Russ Allbery: Review: Witches Abroad

Review: Witches Abroad, by Terry Pratchett
Series: Discworld #12
Publisher: Harper
Copyright: 1991
Printing: February 2008
ISBN: 0-06-102061-3
Format: Mass market
Pages: 350
Witches Abroad is the twelfth book in the Discworld series, but there's no strong reason why you couldn't start here. It's the second book about the three witches (Granny Weatherwax, Nanny Ogg, and Magrat Garlick), following Wyrd Sisters, and the third book about Granny Weatherwax, but it doesn't assume any knowledge of the previous books or of Discworld in general. Desiderata Hollow is dying. This is not a surprise; she's known for a long time exactly when she was going to die, and that time has come. She's not particularly bothered by it, but it does pose one difficult problem. She's a fairy godmother, as well as a witch, and she's balancing another fairy godmother because they come in pairs. With her dead, Lilith seems likely to win their long struggle, and that would be a bad thing. She needs to pass her wand on to a successor, but she wasn't the planning sort. At least she claims; this comment of hers turns out to hide an elegant bit of manipulation that leaves her wand in the hands of Magrat and sends the three witches on their way to the city of Genua to confront Lilith. There are two halves to Witches Abroad. The first half is the setup described above and their trip across Discworld. The second half is a sort of retelling of Cinderella, as foreshadowed early on by Desiderata. But the whole book is about stories and story shapes and their head-on collisions with the practical confidence of Nanny Ogg and the endless stubbornness of Granny Weatherwax. I think the three witches are one of Pratchett's best inventions, and Granny Weatherwax the best of the three. She has many of the characteristics that would normally relegate her to a supporting mentor figure: older, very knowledgeable, remarkably good at getting her way and at manipulating situations, and not particularly interested in going on adventures. But Pratchett turns this on end at every opportunity. Granny Weatherwax doesn't act like a mentor at all: she doesn't explain things to Magrat, or anyone else; she's almost constantly bickering with the other witches; and she's a fount of irritated and exasperated opinions about the world. She's one of the best irascibly competent characters in fiction, and she steals every scene she's in, refusing to become a supporting character and staying at the center of the story, despite not being a viewpoint character. (Pratchett wisely keeps her out of the viewpoint role for most of the story, since much of her knowledge and "headology" would be less effective if the reader knew what she was thinking.) The dynamics between the three witches are the best part of this book, and I love all three of them. But I'm also a sucker for fractured fairy tales in general, and Witches Abroad is full of them. Their opponent loves stories and has gathered most of her power from reinforcing and manipulating stories, which means that the density of random stories keeps increasing as they approach Genua. That provides numerous opportunities for the witches to stumble through, analyze, take apart, twist, or untwist numerous familiar stories, ranging from Red Riding Hood to Sleeping Beauty. Pratchett keeps things moving right along, not belaboring connections and not explaining too much, which makes it very easy to keep turning pages. The story does get a bit slower in Genua. There's quite a bit of scene-setting and figuring things out, and while Pratchett maintains the steady stream of humor, it isn't quite as compelling without the ever-changing context. He introduces a bit of voodoo magic, which I found to be the least interesting of the multiple styles of magic that show up here. But there are some absolutely brilliant bits with Nanny Ogg's cat, a wonderfully annoyed Cinderella, and an inversion of the traditional story that kept surprising me. I thought the ending was a bit of an anticlimax, but it does fit the nature of the characters. Despite a few plot short-comings, this is my favorite Discworld book up to this point in the series. Definitely recommended, and not a horrible starting point. Followed by Small Gods in the chronological sense and (later) by Lords and Ladies in the plot sense. Rating: 8 out of 10

24 February 2013

Andrew Pollock: [tech] On owning a Nissan Leaf

I'll soon be disposing of the Nissan Leaf that we leased a few months ago, so I thought it a useful exercise to write about my experiences with it. I am not a car man. I am a gadget man. For me, driving is a means to an end, and I'm much more interested in what I call the "cabin" experience, than the "driving" experience, so this is going to slanted much more that way. That said, I found the Nissan Leaf a fun car to drive, from my limited experiences of having fun driving cars. I liked how responsive it was when you put your foot down. It has two modes of operation, "D" and "Eco". I've actually taken to driving it in "Eco" mode most of the time, as it squeezes more range out of the batteries, but occasionally I'll pop it back into "D" to have a bit of fun. The main difference between the two modes, from a driving perspective, is it seems to limit the responsiveness of the accelerator. In "Eco" mode it feels more like you're driving in molasses, whereas in "D" mode, when you put your foot down, it responses instantly. "D" is great for dragging people off at the lights. It's a very zippy little car in "D" mode. It feels lighter. I've noticed that it has a bit of a penchant for over steering. Or maybe that's just my driving. If I have floored it a bit to take a right turn into oncoming traffic, I've noticed slight over steering. That's about all the driving type "real car stuff" I'll talk about. Now to the driver's "cabin experience". It's absolutely fabulous. I love sitting in the driver's seat of this car. Firstly, the seat itself is heated (in fact all of them are). As is the steering wheel. Nissan has gone to great lengths to allow you to avoid needing to run the car's heating system to heat the car, as doing so immediately drops at least 10 miles off the range. Unfortunately I found the windscreen had a tendency to fog up in the winter rainy periods, so I'd have to intermittently fire up the air conditioning to defog the windscreen. Of course, in the summer months, you're going to want to run the AC to cool down, so the range hit in that situation is unavoidable. I've only had this car from late Autumn until late Winter so far, so that hasn't been an issue I've had to contend with. The dashboard is all digital, and looks relatively high tech, which appeals to my inner geek. It's a dashboard. It tells you stuff. The stuff you'd expect it to tell you. Enough said. The audio system is nice. It supports Bluetooth audio, so one can be streaming Pandora from one's phone, through the sound system, for example. Or listening to audio from the phone. There's also a USB port, and it will play various audio files from USB storage. I found the way it chose to sort the files on a USB stick to be slightly surprising though. I haven't invested the time to figure out how I should be naming files so that they play in the order I expect them to play. The ability to play from USB storage compensates nicely for the fact that it only has a single CD player. (We have a 6 disc stacker in our 2006 Prius). The car also came with a 3 month free trial of Sirius XM satellite radio. This was fun. The only dance music FM station in the Bay Area has a weak signal in Mountain View, and I hate dance music with static, whereas there was an excellent electronic music station that I could listen to in glorious high definition. As long as I wasn't driving under a bridge. There's no way I'd pay money for satellite radio, but it was a fun gimmick to try out. The navigation system is really, really good. I haven't bothered using Google Maps on my phone at all. It gives such good spoken directions, that you don't even need to have the map on the screen. It names all the streets. I couldn't figure out a way to get distances in metric. The telematics service, Carwings, is probably my favourite feature. This is what really makes it feel like a car of the future. Through the companion Android application, I can view the charging status (if it's plugged in) or just check the available range (if it's not plugged in). From a web browser, I can plan a route, and push the route to the vehicle's navigation system. If the car is plugged in, I can also remotely turn on the vehicle's climate control system, pre-warming or cooling the car. It's a little thing, but the door unlocking annoyed me a little bit. I'm used to the Prius, where if you unlock the boot (that's trunk, Americans), or the front passenger door, all the doors unlocked. This was a convenient way of unlocking the car for multiple people as you approached it. With the Leaf, unlocking the boot only unlocks the boot. Unlocking the front passenger door only unlocks that door. It requires a second unlock action to unlock all the doors. I've found this to be slightly cumbersome when trying to unlock the car for everyone all at once, quickly (like when it's raining). Another minor annoyance is the headlights. I've gotten into the habit of driving with the headlights on all the time, because I believe it's safer. In the Prius, one could just leave the headlights switched to the "on" position, and they'd turn off whenever the driver's door was opened after the car was switched off. If you try that in the Leaf, the car beeps at you to warn you you've left the headlights on. It has an "auto" mode, where the car will choose when to turn the headlights on, based on ambient light conditions. In that case, when you turn the car off, it'll leave the headlights on for a configurable period of time and then turn them off. This is actually slightly unsettling, because it makes you think you've left your headlights on. The default timeout was quite long as well, something like 60 seconds. The way multiple Bluetooth phones are handled is just as annoying in the Leaf as it is in the Prius, which disappoints me, given 6 years have passed. The way I'd like to see multiple phones handled is the car chooses to pair with whichever phone is in range, or if multiple phones are in range, it asks or uses the last one it paired with. In reality, it tries to pair with whatever it paired with last time, and one has to press far too many buttons to switch it to one of the other phones it knows about. Range anxiety is definitely something of a concern. It can be managed by using the GPS navigation for long or otherwise anxiety-inducing trips, and then one can compare the "miles remaining" on the GPS with the "miles remaining" on the battery range, and reassure oneself that they will indeed make it to where they're trying to go. The worst case I had was getting to within 5 miles of empty. The car started complaining at me. The charging infrastructure in the Bay Area is pretty good. There are plenty of charging stations in San Francisco and San Jose. I'm spoiled in that I have free charging available at work (including a building at the end of my street, so I never bothered with getting a home charger installed). I've almost never had to pay for charging, so it's been great while gas prices have been on the rise. The car's navigation system knows about some charging stations, so you can plan a route with the charging stations it knows about in mind. The only problem is it doesn't know if the charging stations are in use. If you use the ChargePoint Android app, you can see if the charging stations are in use, but then you have to do this cumbersome dance to find an available charging station and plug the address into the vehicle's navigation system. Of course, what can then happen is in the time you're driving to the charging station, someone else starts using it. I actually got bitten by this yesterday. Would I buy a Leaf again? Not as my sole car. It makes a perfect second/commuter car, but as a primary vehicle, it's too limited by its range. They're also ridiculously expensive in Australia, and Brisbane has absolutely no charging infrastructure.

Antonio Terceiro: Ruby 2.0 released, with multiarch support

Ruby 2.0 was released today. This new version of the language brings some very interesting features, and according to the core team, an effort has been made to keep source level compartibility with Ruby 1.9. Debian packaging is under way and should hit NEW soon. During the last few days I gave more attention to getting the new multiarch support fixed upstream than to the packaging bits, but the remaining packaging work should be pretty much about housekeeping. Next steps from a Debian point of view (after Wheezy is out) include: Now let s get back to fixing RC bugs and getting Wheezy released. :-)

23 February 2013

Dirk Eddelbuettel: Two papers about RcppEigen and RcppArmadillo published

Two papers got published recently. The first one is Bates and Eddelbuettel (2013). It is titled Fast and Elegant Numerical Linear Algebra Using the RcppEigen Package, and provides a pretty thorough introduction to our RcppEigen package which uses Rcpp to provide access to the Eigen C++ template library from GNU R. The paper is out as Volume 50, Issue 5 at the (all electronic, open, and generally awesome) Journal of Statistical Software. A bibtex entry is available. The second paper is Eddelbuettel and Sanderson (2013). This one is titled RcppArmadillo: Accelerating R with high-performance C++ linear algebra and introduces the RcppArmadillo package which brings Conrad Sanderson's Armadillo C++ template library to GNU R by deploying Rcpp. The paper is currently "in press" at Computational Statistics & Data Analysis but the DOI 10.1016/j.csda.2013.02.005 will remain once a volume and issue is assigned by CSDA. Preprints of both papers are available via my papers page, and as vignettes in the corresponding packages. The upcoming Rcpp class in New York will feature Rcpp, RcppArmadillo and RcppEigen. Space is still available.

Sylvain Le Gall: OUnit 2.0 progress

I have recently started to work on OUnit 2.0. The point of this new version will be to adapt OUnit to improve speed and compatibility with third party system: Only the 3 last point needs to be completed. Here is a screenshot of Jenkins reading JUnit output of an OUnit test: Jenkins, OUnit test results So if you have a long standing issue with OUnit, this is the time to submit a bug. OUnit BTS

Daniel Pocock: Checking authors.txt before migrating to github

Ensuring that contributors are correctly recognised for their work is a cornerstone of the free and open source software community. Here I present a convenient script to help. When projects migrate to git (and usually Github these days), there is usually quite a lot of enthusiasm to get up and running and the authors.txt file is not looked at closely, or not at all. Github does a great job of summarising the free software contributions of each member. To do this, it needs to cross-reference their commits with their email addresses. This possibility is not unique to Github though: as git is a distributed version control system, it is quite possible that other services will seek to mirror and report on code contributions in the future. authors.txt can be tedious For a large project with a long history, there may be more than 100 committers, many of them designated by SVN user IDs that are unique to the project and not easily mapped to the user email address. If the project is hosted on Google Code SVN, then Google often makes dummy gmail.com accounts for the committers - and many people don't even use those accounts for anything else, not even as an email account. Including these accounts in a git repository is a bad idea if it is not the person's preferred email address. If they don't have that address associated with their Github account, then their commits won't be easily attributed to them at all. Often, building an accurate authors.txt can be tedious, but here are some steps to simplify it:
  • Use a script like svn-authors-extract to quickly build a template file by scanning the SVN repository.
  • Scan email list history - if necessary, download the email archive as a mailbox, and use regular expressions to extract all email addresses
  • Find out if the SVN server keeps a list of email addresses with the SVN user IDs somewhere
  • Use searches in Google, LinkedIn and various other places to try and find out where the person is now
  • Finally, use the script below to test the results
Testing the results against Github automatically How do you know which email addresses are already matched to a Github account and which need further research? I've written a convenient script to help It creates a dummy repository with one commit per committer. Upload this dummy repository as a new project on Github, view the commit log page, and all the matched user IDs will be highlighted, so the missing ones will stand out and you can quickly focus your search for missing email addresses. I've tested this with the authors.txt file I'm building for the Sipdroid/Lumicall projects. This project comes from Google Code SVN and almost all the identities are obscured by gmail.com addresses that may or may not be the real/preferred email addresses. I created a dummy project on Github called sipdroid-users and pushed the dummy commits there so I can see how many of the contributors are correctly mapped to a Github account. A full copy of the script is below, you can also find it in the sync2git repository: 
#!/bin/bash
set -e
if [ $# -lt 2 ];
then
  echo "$0 <authors file> <dest repo for push>"
  exit 1
fi
AUTHORS_FILE=" pwd /$1"
DEST_REPO="$2"
if [ ! -e "$ AUTHORS_FILE " ];
then
  echo "can't find $ AUTHORS_FILE , aborting"
  exit 1
fi
TMP_REPO= mktemp -d 
TARGET_FILE="testing.txt"
cd "$ TMP_REPO "
git init .
cat "$ AUTHORS_FILE "   while read ;
do
  full_info= echo "$ REPLY "   cut -f2 -d'='   cut -b2- 
  an=" echo "$ full_info "   sed -e "s/ <.*\$//\" "
  am=" echo "$ full_info "   sed -e "s/^.*</</\" "
  cn="$an"
  cm="$am"
  echo "$REPLY" >> "$ TARGET_FILE "
  git add "$ TARGET_FILE "
  export GIT_AUTHOR_NAME="$an"
  export GIT_AUTHOR_EMAIL="$am"
  export GIT_COMMITTER_NAME="$cn"
  export GIT_COMMITTER_EMAIL="$cm"
  git commit -m "Test adding $ REPLY "
done
git remote add origin "$ DEST_REPO "
git push -u origin master

Robert Collins: Simpler is better a single event type for StreamResult

StreamResult, covered in my last few blog posts, has panned out pretty well. Until that is, that I sat down to do a serialised version of it. It became fairly clear that the wire protocol can be very simple just one event type that has a bunch of optional fields test ids, routing code, file data, mime-type etc. It is up to the recipient at the far end of a stream to derive semantic meaning, which means that encoding a lot of rules (such as a data packet can have either a test status or file data) into the wire protocol isn t called for. If the wire protocol doesn t have those rules, Python parsers that convert a bytestream into StreamResult API calls will have to manually split packets that have both status() and file() data in them this means it would be impossible to create many legitimate bytestreams via the normal StreamResult API. That seems to be an unnecessary restriction, and thinking about it, having a very simple here is an event about a test run API that carries any information we have and maps down a very simple wire protocol should be about as easy to work with as the current file or status API. Most combinations of file+status parameters is trivially interpretable, but there is one that had no prior definition a test_status with no test id specified. Files with no testid are easily considered as global scope for their source, so perhaps test_status should be treated the same way? [Feedback in comments or email please]. For now I m going to leave the meaning undefined and unconstrained. So I m preparing a change to my patchset for StreamResult to: This will make the API trivially serialisable (both to JSON or protobufs or whatever, or to the custom binary format I m considering for subunit), and equally trivially parsable, which I think is a good thing.

22 February 2013

Richard Hartmann: Finland II

Second part; bullet points to save time

21 February 2013

Daniel Pocock: US military may need Lumicall

In a remarkable report in Wired Magazine, it has been revealed that US stealth bombers have to communicate with their British allies using conventional radio. What that means in practice is that it would be child's play for the enemy to use basic techniques like triangulation to locate these otherwise invisible aircraft. While the thought of an ineffective multi-billion-dollar stealth bomber program seems preposterous, some may argue that the military has bigger problems maintaining discretion when even the CIA director is busted having an affair via Gmail. After all, it costs nothing to download GnuPG So what could the Americans and British do to put the stealth back into stealth bomber? Maybe it is time that pilots were issued with smartphones running Lumicall - with the built-in encryption features, could it make all their worries go away? At the very least, this issue demonstrates in a remarkable manner the reasons to stick with open standards like XMPP and SIP for building interoperable communications systems. If they missed our talk on Free, open, secure and convenient communications at FOSDEM, that may also be an interesting place to start searching for answers, as the idea of federated real-time communications is just as valuable in the air as it is for business or private purposes on the ground. The video is available now for those who missed it, and my earlier FOSDEM wrap-up provides more food for thought about the relevance of private communications for maintaining individual freedom (with or without the help of airborne supremecy). FOSDEM video: <video controls="controls" preload="none">
<source src="http://video.fosdem.org/2013/maintracks/Janson/Free,_open,_secure_and_convenient_communications.webm" type="video/webm; codecs="vp8, vorbis""></source></video> <object data="http://releases.flowplayer.org/swf/flowplayer-3.2.15.swf" type="application/x-shockwave-flash"> <param name="movie" value="http://releases.flowplayer.org/swf/flowplayer-3.2.15.swf"><param name="allowfullscreen" value="true"><param name="flashvars" value="config= 'clip': 'url': 'http://video.fosdem.org/2013/maintracks/Janson/Free,_open,_secure_and_convenient_communications.webm', 'autoPlay':false, 'autoBuffering':false ">Video tag not supported. Download the video here. </object>

Daniel Pocock: US military may need Lumicall

In a remarkable report in Wired Magazine, it has been revealed that US stealth bombers have to communicate with their British allies using conventional radio. What that means in practice is that it would be child's play for the enemy to use basic techniques like triangulation to locate these otherwise invisible aircraft. While the thought of an ineffective multi-billion-dollar stealth bomber program seems preposterous, some may argue that the military has bigger problems maintaining discretion when even the CIA director is busted having an affair via Gmail. After all, it costs nothing to download GnuPG So what could the Americans and British do to put the stealth back into stealth bomber? Maybe it is time that pilots were issued with smartphones running Lumicall - with the built-in encryption features, could it make all their worries go away? At the very least, this issue demonstrates in a remarkable manner the reasons to stick with open standards like XMPP and SIP for building interoperable communications systems. If they missed our talk on Free, open, secure and convenient communications at FOSDEM, that may also be an interesting place to start searching for answers, as the idea of federated real-time communications is just as valuable in the air as it is for business or private purposes on the ground. The video is available now for those who missed it, and my earlier FOSDEM wrap-up provides more food for thought about the relevance of private communications for maintaining individual freedom (with or without the help of airborne supremecy). FOSDEM video: <video controls="controls" preload="none">
<source src="http://video.fosdem.org/2013/maintracks/Janson/Free,_open,_secure_and_convenient_communications.webm" type="video/webm; codecs="vp8, vorbis""></source></video> <object data="http://releases.flowplayer.org/swf/flowplayer-3.2.15.swf" type="application/x-shockwave-flash"> <param name="movie" value="http://releases.flowplayer.org/swf/flowplayer-3.2.15.swf"><param name="allowfullscreen" value="true"><param name="flashvars" value="config= 'clip': 'url': 'http://video.fosdem.org/2013/maintracks/Janson/Free,_open,_secure_and_convenient_communications.webm', 'autoPlay':false, 'autoBuffering':false ">Video tag not supported. Download the video here. </object>

Biella Coleman: Coding Freedom: The Ethics and Aesthetics of Hacking

Although the book has been out for a number of months, available for purchase and download, Coding Freedom finally has a dedicated home on the Interwebz. Based on my graduate research in anthropology and my dissertation, the book takes an up front and close look at various personal, affective, ethical and political dimensions of free software development. While the book is not on Debian per se, there is one chapter dedicated to the project and a whole lot of Debian developers were interviewed for the book. You can read some reviews and if you like what you see, take a dip.

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