So I got my hands on that new machine, somewhere, somehow, and I had to make myself comfortable on it. The biggest difference in that machine and the ones I used before is the RAID controller, an Adaptec 5405, instead of the 3ware ones I used to have before. That means getting used to new tools, messages and all these things which I ll try to document here.Step 1: does vendor deliver?Well, yes, mostly. There is (mainline) kernel support for the controller, Squeeze s kernel will boot up just fine and I just throw my junk into /dev/sda and it will handle the whole raidy thingy itself. But what is when I want to check the health of the disks, to add a spare or modify the caching? Ask the mighty vendor and it will answer Yes, you can! .So I downloaded that asm_debian_x86_x64_v6_50_18570.tgz, unpacked and faced two debs, one i368 and one amd64. Yes, you could have saved half of the bandwidth if someone would have asked for the arch before, but who cares for some additional 60MiB today? So let s see what it does. Oh no, wait, there is a README ASM_IUG_for_Debian_and_Ubuntu.txt:

1. Make sure to be in root level access.
2. Install the ASM storman .deb package. For example, if the package is storman_6.50-18570_i386.deb,
   then install it using the following command dpkg -i storman_6.50-18570_i386.deb
3. Adaptec Storage Manager will get installed at /usr/StorMan
4. Add the line /usr/StorMan to /etc/ld.so.conf. Then run "ldconfig". This is needed for the arcconf
   utility to find the path of the libstdc++.so.5 library

Well, 1 is obvious, so is 2.
For 3: hum, /usr/StorMan? Ever heard of FHS? Don t think so.
For 4: WTF?! I prefer to get libstdc++5 from my local Debian mirror instead.But at least they provide a .deb, right? Uhm, no, it s an RPM converted via alien :( And don t dare to look at preinst, postinst and postrm (it extracts an own copy of Sun JRE 1.6u16, chmods around wildly on install and does rm -rf something on uninstall, did I see that some days ago on the webs?). Let s get rid of that package as soon as possible, I decided, and just keep arcconf (which will be described later), esp because StorMan itself seems to include some call-home functionality which I d like not to have:

cp -a /usr/StorMan/arcconf /usr/local/sbin/
apt-get remove --purge storman

Step 2: does community deliver?You can, by the way, get (better) packages at http://hwraid.le-vert.net/wiki/DebianPackages from Adam C cile (Le_Vert). I didn t test those much, but I currently use the arcconf package from there, which seems to be exactly what I need: proper dependencies and just the arcconf binary, no Java sh*t.Step 3: monitor the controllerAs this post is about monitoring, not ranting, let s continue. As mentioned before, I only have arcconf installed, which is just a cli to do stuff with the controller. If I understood the docs right, the actual StorMan is able to send notification mails when a disk dies or the controller gets eaten by aliens, but as I don t have StorMan, I have to do things myself.Adam has a aacraid-status package in his repository, which includes some minimalistic shell-daemon to monitor the output of arcconf. It didn t perfectly fit my needs (and had some hickups with my disks which refuse to report a vendor, whyever), so I decided to write something myself (slightly based on what Adam has done in aacraid-status, though).The result is on GitHub: https://github.com/evgeni/aacraidAs you can see the code contains (at the time of writing) exactly ZERO comments and there is no README either, but it s actually quite usable already.

• aacraid.py is the main magic inspired by Adam s aacraid-status, basically just parsing arcconf output
• aacraid-status prints all useful info about all controllers, arrays and disks (the output is pretty much like Adam s)
• aacraidd is a small daemon which will monitor all controllers every (per default) 5 minutes and mail you in case of status-change

I am now running aacraidd and get happy mails when something breaks :) [running = running from /etc/rc.local, no init script yet :)]Step 4: monitor the disks via smartmontoolsThere is one little problem I have with arcconf: it s closed source and does magic to the controller.With the old 3ware controller I was able to monitor the disks with smartmontools/smartd using something like this:

/dev/twa0 -d 3ware,0 -a -s L/../../2/01 -m root
/dev/twa0 -d 3ware,1 -a -s L/../../2/03

This is possible with Adaptect controllers too (not through /dev/twaX obviously). You have to have the sg module loaded, which will result in /dev/sg[012] on my machine, with sg0 being the controller itself and sg1/sg2 the both disks attached to it. Having sg loaded, one can now use smartd with:

/dev/sg1 -d sat -a -s L/../../7/01 -m root
/dev/sg2 -d sat -a -s L/../../7/02 -m root

(-d sat is the important option here!)Thanks to Thomas Krenn Wiki: Smartmontools mit Adaptec RAID Controller for the basic info and ostlogd.spenneberg.net: Adaptec-Raid-Controller S.M.A.R.T.-Healthstatus monitoren for the pointer to the sg module!Step 5: relaxYupp, 4 steps are enough, go relax until the next disk dies (you will be doing something REALLY important that moment according to Murphy).

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It took a long time to get all the parts of the Xen support into the Linux kernel. While rudimentary Dom0-support was available since 2.6.38, support for device backends were missing. It was possible to replace this backend with a userspace implementation included in qemu, but I never tested that. With Linux 3.0, both the traditional block backend and the network backend are available. They are already enabled in the current 3.0-rc3/-rc4 packages in experimental, so the packages can be used as Dom0 and run guests. Right now the backend modules are not loaded, so this still needs some work. Neither the init scripts loads them, because the names where in flux the last time I laid hand on it, nor does the kernel themself expose enough information to load them via udev. I think using udev to load the modules is the way to go. This step marks the end of a five year journey. Around 2.6.16 the Xen people started to stay really close to Linux upstream. With the 2.6.18 releas this stopped and the tree was pushed in different states into Debian Etch and RHEL 5. After that, Xen upstream ceased work on newer versions completely, only changes to the now old 2.6.18 tree where done. SuSE started a forward port of the old code base to newer kernel versions and Debian Lenny released with such a patched 2.6.26. Around that time, minimal support for DomU on i386 using paravirt showed up and Lenny had two different kernels with Xen support. Since 2.6.28 this support was mature and works rather flawless since. Somehow after that, a new port of the Dom0 support, now using paravirt, showed up. This tree based on 2.6.32 is released with Debian Squeeze. After several more rounds of redefining and polishing it is now mostly merged into the core kernel. I don't know what the future brings. We have two virtualization systems supported by Linux now. The first is KVM that converts the kernel into a hypervisor and runs systems with help of the hardware virtualization. The later one is Xen that runs under a standalone hypervisor and supports both para- and hardware virtualization. Both works, KVM is easier to use and even works on current System z hardware. It can be used by any user with hopefully enough margin of security between them. Xen's home is more suited for servers, where you don't have users at all. Both have advantages and disadvantages, so everyone have to decide what he needs, there is no "one size fits all".

forked-daapd v0.17 is out; the main purpose of this release is to add support for libav 0.7. There are also a few bugfixes that made it into this release, but nothing earth-shattering. One More Thing You ll notice an extra tarball and tag in this release, both marked 0.17gcd. With this release, the GCD (Grand Central Dispatch / libdispatch) codebase is making its debut. libdispatch replaces libevent and allows for greater concurrency inside forked-daapd. This makes forked-daapd snappier, which shows when using Remote or a SoundBridge. The filescanner also benefits from this; it now scans several directories concurrently, reducing the time needed for a rescan by making better use of the machine resources. Thanks to Mark Heily s efforts on libdispatch/libkqueue/libpthread_workqueue over the past year, we now have a Linux version of libdispatch that works well enough to support forked-daapd. This codebase will become the primary codebase for forked-daapd once the database performance issue will be fixed. After this point, the current libevent 1.4 codebase will be legacy and won t see any further development (we ll discuss bugfixes in due time). This new codebase comes with new requirements:

• the Clang compiler from the LLVM project is required, due to the use of the C Blocks extension that isn t supported by GCC;
• libdispatch, of course, is required;
• libtre is a new dependency for concurrent regexps;
• glibc 2.13+ is required, or any glibc version containing a fix for glibc BZ#10563.

libdispatch and its dependencies are available in Debian unstable; it s best and easier to use whatever is in unstable, instead of mixing and matching the libdispatch/libkqueue/libpthread_workqueue versions until they all work together. Due to platform support in Clang, the GCD codebase can only be built for and will only run on i386 and amd64, as far as Linux is concerned. Other architectures will have to wait until support for them is added to Clang. FreeBSD is untested and will probably require some modifications to work; recent enough versions of FreeBSD have a native pthread_workqueue implementation and do not need libpthread_workqueue. Packages are available in experimental for Debian users; they ll end up in unstable in a few weeks, before the libevent2 migration happens there. Tarballs available at http://alioth.debian.org/~jblache/forked-daapd/ ; GPG signatures made with my Debian key F5D65169.

This is a kernel module I cooked in a couple of days. The idea is to expose a v4l device that gets its data from user space.

I had 2 use cases in mind:
1) Educational purpose for myself (I'm really a kernel noob).
2) Streaming movies over skype, google talk, ... etc.

The idea could be good or completely rubbish but hey ? Learning can only be done with stupid ideas!

The code is highly unstable. It shouldn't oops the kernel but I'm not responsible. I've been developing and testing it inside qemu.

Clone it from the git repository via:

Here are a few missing bits off the top of my head:

* I'm not following the kernel coding style yet ;-)
* I'm sure my locking, unlocking and concurrency handling is flawed.
* The code is a bit fragile.
* It'd be nice to implement mmap support for the character device. This should eliminate data copies.
* Perhaps expose the character device all the time and generate "fake" frames when streaming starts ? Problem now is one has to be very fast in feeding data to the module otherwise select() on the v4l device will timeout.
* Many more...

If someone finds this idea useful, please drop me a line.
Comments, use cases, ideas and tips are really welcomed!

If I see a lot of interest, I might try to push it to the kernel tree one day ;-)

Update: Seems vloopback already exists and renders my code useless. I might still do something with it as my idea seems a bit simpler but whatever.

Update 2: There's also v4l2loopback and its fork. read more

The upstream and debian packages for psmisc version 22.14 were released tonight. This version has a lot of bugfixes. I ve also taken some time to clean up some of the minor compile warnings I used to get which were mainly variables set but not used. Two bugs that I ll concentrate on getting fixed for the next version are all about the command line. The first is that the fuser -s flag changes the return code for items found. It should be consistent so it doesnt matter if fuser displays values or not, 0 means found something and 1 means didn t find it. I can see why in the code it might be different, because the code follows different paths with the s option, but not exactly where the problem is. The second bug is the -M flag for fuser only works if it is before the mount points so -M -m /foo works but -m /foo -M does not. Unlike the -s problem, I can see where it is failing. Currently fuser scans the options one by one. If it finds a -m option, it checks at that point if the -M option is set. The solution is to store all potential targets and only after exhausting the entire command line do we add the potential targets to our real targets. It means scanning the command line, or a subset of it, twice but the performance penalty is tiny. Finally, I released there was a rather neat Makefile command make distcheck . This target makes a tar.g archive, extracts it, builds then cleans. It is a very good program for trapping things like a file exists in your local directory but is not included in the tar.gz (lists.h was missing until I ran this). For some make distcheck is something they re known for years, but if you have an autotools package you develop, have a look at it. With all the talk about testing and test driven releases, I was going to put some test cases in. The problem is there doesn t seem to be an easy way to do testing. I might have to just hack up some scripts but surely there is a better way. That would trap, for example that fuser -s returns 1 but fuser returns 0. I looked at check, but it doesn t work for single-file programs like psmisc is mainly made of.

Yupp, it s this time of the month again! Rhonda has already spammed about it, but I think repeating won t hurt: the next (4th) meeting of the Debian/Ubuntu Games Team will be held in #debian-games on June 26th at 10:00 UTC.

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Well, every once in a while we re forced to do something that isn t particularly interesting or pleasant. Last week it happened again: I had to import a few pretty big PSTs (most 2Gig, one 10Gig, with about 100.000 emails) into our dovecot IMAP. Doing this with Outlook itself was out of the question: it took way too long, even on the local network (many hours for a 1G file) and was prone to hanging and crashes, which were obviously a pain to debug and start over.
Thunderbird was unfortunately not much better, since at least in our tests it didn t import the read status of the emails (they were all marked as unread) and also wasn t particularly good at handling folders with strange names, containing . , / or some more obscure characters. We had used it before for smaller files, where manually dealing with the problems was acceptable, but this time it required something a bit more elaborate, if we were to keep our sanity. Enter libpst. It includes the handy readpst utility which dumps all emails in usable formats in a directory tree, one directory per folder. Unfortunately the Debian version is somewhat outdated and doesn t support the newer Outlook formats, so I did some packaging and even a little bit of patching. It seems Thunderbird also uses this library, which would explain why it didn t handle the Read-Status (haven t confirmed this though; just read it somewhere). The last step was this not-so-little script, which uses the dumped directories from readpst and imports them in IMAP. It would have probably been a bit more elegant to use libpst directly, but I unfortunately didn t have the time to mess around with that. I did have to mess around a lot with encodings though, ergo the unholy chaos with unicode()s and str.encode()s thrown around like rice at a wedding (I could never really wrap my head around charset problems; the subject boggles my mind to this very day). Another useful automation is using the mappings file, which looks something like to automatically import in the right destinations, in case you have a standardized structure.

Even with the availability <video> tag in HTML5, most websites still require the use of Adobe Flash plugin to access some content. If you run a 64-bit (Intel architecture) version of Debian, you can still get this plugin through the flashplugin-nonfree package. Unfortunately, Adobe never commited to a decent support for the 64-bit version of its plugin. The first 64-bit version was provided as late as the fall of 2008. The support was discontinued. Then, we recently got a new preview release but it is still lagging behind the 32-bit version. The 64-bit plugin has two major drawbacks:

• it is not up-to-date and plagued by several security holes which are not planned to be corrected for the 64-bit version;
• it exhibits some bugs of its own, like some sound artifacts which come from the use of memcpy() in place of memmove() and only happens with recent GNU libc (where memcpy() has been optimized and is no longer equivalent to memmove()). Adobe has no plan to fix this. There are several way documented in the bug report to circumvent this bug.

Even if you fix the second point, you have no way to fix the first one. What are the alternatives?

Lightspark Lightspark is a modern, free, open-source Flash player implementation featuring JIT compilation (with the help of LLVM) and hardware acceleration using OpenGL. It only supports Actionscript 3 (introduced in Flash 9) but it now fallbacks to Gnash if an older version is required. The main problem of Lightspark is that it is optimized for modern hardware and uses OpenGL textures to display video frames. This allows to achieve video compositing with the help of the graphic card. Unfortunately, if you use a video card with poor OpenGL performance, like a NVidia card with Nouveau driver, Lightspark is slow as hell. It works well with an Intel card. Currently, Lightspark is only available in experimental for Debian. Install browser-plugin-lightspark.

Gnash Gnash is a more mature project but does not support Actionscript 3. Youtube works well with Gnash, as well as most other applications unless they use too recent features. If your use of Flash is limited, it is a nice alternative. Unfortunately, more and more content are delivered with an application requiring Actionscript 3 support. On Debian, you can get started by installing browser-plugin-gnash.

32-bit Flash plugin on Debian Ubuntu provides Flash as a 32-bit plugin with the help of nspluginwrapper which is a special plugin that will enable the use of a 32-bit plugin inside a 64-bit browser. This seems a sensible choice since Adobe only really supports the 32-bit version. You can also use nspluginwrapper with Debian. You need to download 32-bit version of Flash, uncompress it and put libflashplayer.so in ~/.mozilla/plugins.

# aptitude purge flashplugin-nonfree
# aptitude install nspluginwrapper lib32asound2-plugins
$ cd ~/.mozilla/plugins
$ nspluginwrapper -i $PWD/libflashplayer.so

Beware that you need to watch for updates yourself. Mozilla provides a website checking if plugins are up-to-date. It works with other browsers than Firefox. This is a pity to still need this kind of hack in 2011 but it seems that this is currently the best solution. UPDATED: In a comment, Paul Rufous tells debian-multimedia.org repository provides flashplayer-mozilla package which is the 32-bit plugin with nspluginwrapper.

HTML5 Thanks to the <video> tag available in HTML5, most videos should be available without the need of a special plugin. Unfortunately, HTML5 does not define a list of video codecs and container formats that should be supported by any browser. Therefore, some browsers support Ogg Theora, some others H264 and some of them also support WebM, the new royalty-free format from Google. You can find a good summary of the problem from Mark Pilgrim. With Chromium as found in Debian, you have Ogg Theora, WebM and H264. Youtube has an opt-in program to enable HTML5 video but most other video content are just unavailable without Flash. Web without Flash is not a reality yet.

Grab video with helper tools UPDATED: Josh Triplett pointed in a comment the existence of several command line tools that could be used to download Flash video from popular websites. Those tools include:

• youtube-dl
• get-flash-videos
• clive

Those tools can be useful even if you have installed a Flash plugin since they allow the use of the video player of your choice (better performance, working fullscreen mode). UPDATED: Another solution provided in a comment: Video DownloadHelper extension allows to extract videos from the current web page. In another comment, this is the extension FlashVideoReplacer which is featured. It replaces the Flash container with a standalone player.

My internship is now finished, this means that I will be able to work on my GSoC project a lot more than the previous weeks. I hope to make some good progress in the next days.

This last 2 weeks, I was still studying how Jigsaw works. Even if there is no progress on the Jigsaw packaging I have done some packages that will help later.

I ve spend a lot of time trying to package JT Harness and JTReg.
I ve successfully built JT Harness using CDBS but I ve finally rewritten the package using only debhelper and javahelper. Javahelper was really useful to build JAR files, move them to the right directory, put the Javadoc in the right place as well as the examples. The Debian directory of JT Harness can be found on the Java team SVN.

svn co svn+ssh://$ SVN_USER @svn.debian.org/svn/pkg-java/trunk/libjtharness-java

The source package of jtharness build 2 binary packages: libjtharness-java and libjtharness-java-doc. You can see that by looking at the control file in the debian directory. There are some interesting files in this package, let s take a look at them.

First of all, some of the source files needed to be patched for the package to build. So to accomplish this, there is a couple of patches in debian/patches :

• dependencies.diff, used to locate JAR files in /usr/share/java , and,
• rxtx.diff, done by Tom Marble used to change some imports from javax.comm to gnu.io .

To generate these patches, I ve used the edit-patch command which is a really awesome tool. This command uses a temporary shell where we can edit files we want to patch. When the job is done, CTRL + D terminates the temporary shell and the patch is generated.

There are 4 interesting files which are used to build the binary packages and put the files in the right directories. These files are:

• rules,
• libjtharness-java-doc.install,
• libjtharness-java.jlibs, and,
• libjtharness-java-doc.javadoc.

Of course rules is the most important one. This file tells us how packages are built. A good thing is that rules is quite simple in the jtharness case.

#!/usr/bin/make -f
JAVA_HOME = /usr/lib/jvm/default-java

override_dh_auto_build:
ant -f build/build.xml

%:
dh $@ --with javahelper

We just tell where Java is and to use javahelper ( with javahelper). Overriding dh_auto_build is interesting because since the JT Harness uses Ant as build system we need to give to Ant where the build.xml file is. By default Ant is searching it in the current directory but in jtharness the file is in the build directory. Since the Ant build file is correctly written, the build generates JAR files, Javadoc and examples code. And libjtharness-java* files are here to put the generated things in the right places.
The job of libjtharness-java.jlibs is to tell where to find the JAR libraries. In this case, the intesresting JAR files were javatest.jar and jt-junit.jar . So in the .jlibs file we just give where those files are after being built.
The job of libjtharness-java-doc.javadoc is to tell where the Javadoc is and where to put it. So there is only one line that says the generated Javadoc is in jar-build/javadoc and put it in /usr/share/doc/libjtharness-java/api .
And finally, libjtharness-java-doc.install is used to move the examples. The syntax is same as libjtharness-java-doc.javadoc .

The JT Harness package can be found in Sid now thanks to Sylvestre Ledru who uploaded it for me. So the ITP bug that I created is now closed.

Building the package for jtreg is quite similar. In fact, it probably easier but I m still facing a problem. jtharness is just a library, jtreg does have main classes and generate some binaries. The difficulty here is to generate the man pages for the 2 generated binaries: jtdiff and jtreg. These 2 files are shell scripts which just use jtreg.jar with the correct parameters.

I tried several tools to generate the man pages of each script. Sadly, I can t find a way that does not causes any problems.
My first choice was to use help2man. This tool looked like to be perfect for the job. But I couldn t find how to launch the scripts correctly. The scripts needs jtreg.jar but they also need javatest.jar from the libjtharness-java package. The classpath cannot be set correctly due how the scripts are written. So to use help2man I ll probably have to patch and completely rewrite jtdiff.sh and jtreg.sh in the sources.
My second choice was to use txt2man. During the build of jtreg there is a usage.txt file which is generated and which can be used as a man page. txt2man can take this text file and output a man page based on the text. I thought it was working but when building the package, lintian threw some warnings about syntax errors in the man pages.

W: jtreg: manpage-has-bad-whatis-entry usr/share/man/man1/jtdiff.1.gz
W: jtreg: manpage-has-errors-from-man usr/share/man/man1/jtdiff.1.gz 292: warning [p 4, 3.3i]: cannot adjust line

Finally, few days ago I decided to try rst2man. This tool looks cool and easy to use. But the text that I have to convert into a man page is not a reStructured text so it cannot without patching the usage.txt file for example. I was going to do it but there is no such file in the sources of jtreg. Actually this file is generated during the build but the text had to come from somewhere. And it was from two properties files in the source code.
I m still looking for a good solution to generate the man pages. If someone has any idea just let me know

The debian packaging of jtreg is not in the Java team SVN yet because of the man pages problem. I opened an ITP bug so people know that someone is working on jtreg.

My goal for the next two weeks is to finish the jtreg package, understand how jpkg (which is supposed to create Debian packages) works in Jigsaw and write more examples using the modular JVM.

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Vuoden 2007 lopussa Siebrand asetti lokalisointitavoitteet MediaWikille.Tavoitteet olivat todella kunnianhimoisia. N ytt kin silt , ett n ihin ei p st . Emme kuitenkaan aio luovuttaa ilman taistelua. Viel on vajaa viikko aikaa saavuttaa nuo tavoitteet. Sin voit auttaa saavuttamaan tavoitteet suomen kielen osalta.

Yhteisty ss Stichting Open Progressin kanssa pystymme tarjoamaan sinulle kannustusta. Tarjoamme 1000 euroa jaettuna kaikkien k nt jien kesken, jotka ovat tehneet yli 500 uutta k nn st MediaWikiin ja sen laajennuksiin vuoden loppuun menness .

My s muut Betawikin projektit kaipaavat apua. Kiinnostaisiko sinua k nt vaikkapa FreeCol-peli tai Mantis-virheenseurantaj rjestelm . Yst v llinen ja yhteisty kykyinen ymp rist saattaa sinut vauhtiin sek auttaa sinua kehittym n suomentajana parantamalla k nn ksi yhdess .

Betawiki l ytyy osoitteesta http://translatewiki.net.
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(l hde)

Katso my s http://lokalisointi.org/.

Edit Aug 18th: video available (ogv, also on youtube)

Forget AMD, Intel, NVIDIA! Thomas White's incredible work with Neo FreeRunner's puny graphics dec...accelerator, Smedia Glamo 3362 is starting to bear fruits. Not listening to such comments as the chip will never be used anywhere else and why not spend your time doing something more relevant , he has chosen to actually do what he likes and sees as an interesting challenge. And that's often the spirit of free software, so I don't really agree with the naysayers.

The camera shot on the right, running KMS-enabled X.org driver for the glamo chip on my Debian installation (visible software matchbox-window-manager, fbpanel, zhone), is a bit optimistic looking since Zhone happens to draw correctly. A lot of the drawing is not yet synced correctly, which shows as all text and images in eg. GTK applications being garbled. But as little as two days ago one couldn't yet much launch applications without X crashing, so the newest commits by Thomas were a big step forwards. I'm using Debian, and he's not, so I try to find time to help in debugging even though I really can't much help with the driver code.

The driver is not just one piece of code, but consists of a kernel drm driver (direct rendering manager) using GEM, libdrm support for the kernel driver and finally the X.org driver supporting these other components and offering buzz-words like DRI2. There is also a beginning of a Mesa 3D driver, though it is so far just a skeleton driver since the 2D/KMS/EXA/DRM parts are what should be done first before dwelling into the OpenGL realm.

Openmoko the company is basically nowadays just producing new Neo FreeRunners to resellers, but the community of the so far only Free phone is thriving. The final (Openmoko produced, from where gta02-core continues) version of the phone, with the famous buzzing problem fixed, appeared on store shelves some time ago, offering better out-of-the-box phone functionality in addition to all the mini computer features. It was also offered to Debconf visitors on discount.

It's not only cool to have kernel mode-setting, though it is indeed very cool as well. The reason for much sorrow in the whole OM project has been the graphics chip, and some of the problems with the chip are only finally solvable with the kernel doing the mode-setting. So it's both a very modern thing to use KMS, but there are also clear potential benefits of having accurate control over this very sensitive piece of silicon. The current non-KMS X.org driver for example busy loops in order to try to feed the chip at a correct pace, causing CPU usage every time there is any drawing going on.

This is somehow reminding me about getting the best out of 8-bit computers and other hardware with some specific limitations. The glamo chip is very limited in some ways, but also capable in some other ways like theoretically offering MPEG-4 decoding, OpenGL ES 3D support. It's a mixed bag of things, and I can very well imagine it's indeed an interesting challenge to work on it, if you just have the skills (I don't) and nerves (proper debugging tools help).

It's so nerdy to drool over lines in the X.org log, but I just can help it:

X.Org X Server 1.6.3
Release Date: 2009-7-31
X Protocol Version 11, Revision 0
Build Operating System: Linux 2.6.28 armv5tel Debian
Current Operating System: Linux neo 2.6.29-GTA02_mydrm #2 PREEMPT Mon Aug 17 18:24:39 EEST 2009 armv4tl
...
II) Using KMS!
...
(WW) Glamo(0): EXA hardware acceleration initialising
(II) EXA(0): Driver allocated offscreen pixmaps
(II) EXA(0): Driver registered support for the following operations:
(II) Solid
(II) Copy
(II) Glamo(0): Initialized EXA acceleration
...
(II) Glamo(0): RandR 1.2 enabled, ignore the following RandR disabled message.
...
(II) Glamo(0): [glamo-dri] Name of DRM device is '/dev/dri/card0'
(WW) Glamo(0): [DRI2] Version 1 API (broken front buffer rendering)
(II) Glamo(0): [DRI2] Setup complete
...
(II) AIGLX: enabled GLX_MESA_copy_sub_buffer
(II) AIGLX: Loaded and initialized /usr/lib/dri/glamo_dri.so
(II) GLX: Initialized DRI2 GL provider for screen 0
(II) Glamo(0): Adding framebuffer....!
(II) Glamo(0): 8 480 640 16 16 960
(II) Glamo(0): rootPixmap = 0x1d0a00
(II) Glamo(0): Done

I'm writing a blog entry instead of just replying to myself on a mailing list, since this subject might be interesting to a largish portion of the community. Most people assume things just magically work out by themselves and then after a release wonder why it wasn't so.

So, I raised a question on ubuntu-devel-discuss mailing list about whether usb-modeswitch should be included in the default Ubuntu 10.04 LTS installation instead of it only being in the universe repository. Reason was simply that firstly, I've read some general wonderings from the community about why it isn't already so. Secondly, without it my 3G modem (Huawei E1552) was first not functional, but right after installing usb-modeswitch package Network Manager worked smoothly with it.

Since I didn't get much discussion going on besides some statements that it doesn't work for everybody and even has caused extra problems for some others (in 9.10), I asked for a small round of comments on the subject on IRC. The channels are logged so I believe I can quote those a bit.

Colin Watson said among else:

"surely we just want the kernel to DTRT [do the right thing] by default ... this is the upstream trend ... it already DTRT for quite a few devices"
"I'd be very concerned about advertising that it's the Way to get things to work, and thus undermining getting things fixed in the kernel"
"I agree that usb-modeswitch is often a way to get otherwise non-working hardware to work ... I'm just not very convinced it's a real properly supportable option"
"but I'm just another user from this point of view, albeit one who ended up in quite a few discussions with various appropriate upstreams last time round :)"

Later on Paul Sladen continued a bit, among else:

"usb-modeswitch is a very long-winded way of sending a single usb-mass-storage command to the device's first profile"
"grep -hr MessageContent usb_modeswitch.d/ sort -n uniq -c sort -rn shows the level of duplication in the configuration files"
"...I do like that it is done in userspace though, as so easy to disable if you wanted something else".

Meanwhile I also IM:d a bit with Antti Kaijanm ki from whom I probably originally coined the idea of following whether usb-modeswitch is integrated into Ubuntu or not. He mainly said that he doubts the feasibility of updating kernel's USB storage quirks in a stable release, compared to having stable release upgrades about the usb-modeswitch-data udev rules. He also proposed discussing maintainability and usability by distros with the Debian maintainer and upstream, although it sounds like Colin might have had some talks already.

So there we are now. Apparently at this point it is hoped that as many quirks as possible are inserted in the kernel, see for example drivers/usb/storage/unusual_devs.h in the kernel. But if you have concerns about if 10.04 LTS will be kept up-to-date regarding 3G modems and want to somehow participate in bringing usb-modeswitch into Ubuntu default installation or simply discuss how to handle the kernel SRUs properly, it's time to stand up and do something.

Should there perhaps be a process with which the usb-modeswitch developers would get the information they are gathering more easily to the upstream kernel _and_ (older) distribution kernels? Is this simply a case of being easier to address an issue with a "hackish" approach, or is the usb-modeswitch actually the right way to go?

Note that I'm no expert in this area, I simply become interested in various subject from time to time :)

-Timo, going to figure out a kernel quirk for his 3G modem

The first concrete outcome from the Debian derivatives census is the creation of Planet Debian Derivatives. For those of you who are interested in the activities of distributions derived from Debian, it aggregates the blogs and planets of all the distributions represented in the derivatives census. The list of feeds will be expanded semi-automatically as more distributions participate in the census and maintainers of census pages add new blog and planet URLs. Many thanks to Joerg Jaspert for doing the necessary setup procedures for the addition of the new sub-planet to Planet Debian. I'm glad that it was accepted alongside the sole language-based sub-planet (Planet Debian Spanish). I plan further integration of information about derivatives with Debian infrastructure. My next target will be integration of information about the packages in Debian derivatives into Debian. I hope to work on getting that information into UDD (and rmadison) and the packages.d.o site during DebConf11 and DebCamp. If you are interested in helping out, please add your ideas to the integration wiki page, check out the code and add more scripts to it. If you have any comments or questions about this or any other activities related to Debian derivatives, please direct them to the debian-derivatives list and the #debian-derivatives IRC channel on OFTC. Those of you interested in the other side of the software stream might want to take a look at Planet Debian Upstream, which is run by the excellent Joey Hess. He is also on the lookout for interesting blogs by people writing software that is packaged in Debian. The site is created using ikiwiki, hosted on branchable and editable with an OpenID account.

I procrastinated to look up this for such a long time.. today was enough. What I want to achieve is reading a line from stdin and split it among several variables, naively I'd do:

$ echo "A BB CCC" read a b c
$ echo $a $b $c


(no output.) As well explained here the above code doesn't work, but this one does:

$ read a b c < <(echo "A BB CCC")
$ echo $a $b $c
A BB CCC

as a hint, <(cmds) is called process substitution.

I mentioned this briefly yesterday, but now I'll try to summarize the story of a great surprise and a big moment for me. All this started when my wife Elizabeth and my son Jean-Baptiste wanted to do something special for my 50th birthday. So, it indeed all started months ago, probably early March or something (I don't yet have all the details). Jean-Baptiste described this well on the web site, so I won't go again into details, but basically, this was about getting birthday wishes from my "free software family" in, as you might guess, as many languages as possible. Elizabeth brought the original idea and JB helped her by setting up the website and collecting e-mail addresses of people I usually work with: he grabbed addresses from PO files on Debian website, plus some in his own set of GPG signatures and here we go. And then he started poking dozens of you folks in order to get your wishes for this birthday. Gradually, contributions accumulated on the website, with many challenges for them: be sure to get as many people as possible, poking and re-poking all those FLOSS people who keep forgetting things... It seems that poking people is something that's probably in the Perrier's genes! And they were doing all this without me noticing. As usually in Debian, releasing on time is a no-no. So, it quickly turned out that having everything ready by April 2nd wouldn't be possible. So, their new goal was offering this to me on Pentecost Sunday, which was yesterday. And...here comes the gift. Aha, this looks like a photo album. Could it be a "50 years of Christian" album? But, EH, why is that pic of me, with the red Debconf5 tee-shirt (that features a world map) and a "bubulle" sign, in front of the book? But, EH EH EH, what the .... are doing these word by H0lger, then Fil, then Joey doing on the following pages? And only then, OMG, I discover the real gift they prepared. 106, often bilingual, wishes from 110 people (some were couples!). 18 postcards (one made of wood). 45 languages. One postcard with wishes from nearly every distro representatives at LinuxTag 2011. Dozens of photos from my friends all around the world. All this in a wonderful album. I can't tell what I said. Anyway, JB was shooting a video, so...we'll see. OK, I didn't cry...but it wasn't that far and emotion was really really intense. Guys, ladies, gentlemen, friends....it took me a while to realize what you contributed to. It took me the entire afternoon to realize the investment put by Elizabeth and JB (and JB's sisters support) into this. Yes, as many of you wrote, I have an awesome family and they really know how to share their love. I also have an awesome virtual family all around the world. Your words are wholeheartedly appreciated and some were indeed much much much appreciated. Of course, I'll have the book in Banja Luka so that you can see the result. I know (because JB and Elizabeth told me) that many of you were really awaiting to see how it would be received (yes, that includes you, in Germany, who I visited in early May!!!). Again, thank you so much for this incredible gift. Thank you Holger Levsen, Phil Hands, Joey Hess, Lior Kaplan, Martin Michlmayr, Alberto Gonzalez Iniesta, Kenshi "best friend" Muto, Praveen Arimbrathodiyil, Felipe Augusto van de Wiel, Ana Carolina Comandulli (5 postcards!), Stefano Zacchiroli (1st contribution received by JB, of course), Gunnar Wolf, Enriiiiiico Zini, Clytie Siddall, Frans Pop (by way of Clytie), Tenzin Dendup, Otavio Salvador, Neil McGovern, Konstantinos Margaritis, Luk Claes, Jonas Smedegaard, Pema Geyleg, Meike "sp tzle queen" Reichle, Alexander Reichle-Schmehl, Torsten Werner, "nette BSD" folks, CentOS Ralph and Brian, Fedora people, SUSE's Jan, Ubuntu's Lucia Tamara, Skolelinux' Paul, Rapha l Hertzog, Lars Wirzenius, Andrew McMillan (revenge in September!), Yasa Giridhar Appaji Nag (now I know my name in Telugu), Amaya Rodrigo, St phane Glondu, Martin Krafft, Jon "maddog" Hall (and God save the queen), Eddy Petri or, Daniel Nylander, Aiet Kolkhi, Andreas "die Katze geht in die K che, wunderbar" Tille, Paul "lets bend the elbow" Wise, Jordi "half-marathon in Banja Luka" Mallach, Steve "as ever-young as I am" Langasek, Obey Arthur Liu, YAMANE Hideki, Jaldhar H. Vyas, Vikram Vincent, Margarita "Bronx cross-country queen" Manterola, Patty Langasek, Aigars Mahinovs (finding a pic *with* you on it is tricky!), Thepittak Karoonboonyanan, Javier "nobody expects the Spanish inquisition" Fern ndez-Sanguino, Varun Hiremath, Moray Allan, David Moreno Garza, Ralf "marathon-man" Treinen, Arief S Fitrianto, Penny Leach, Adam D. Barrat, Wolfgang Martin Borgert, Christine "the mentee overtakes the mentor" Spang, Arjuna Rao Chevala, Gerfried "my best contradictor" Fuchs, Stefano Canepa, Samuel Thibault, Eloy "first samba maintainer" Par s, Josip Rodin, Daniel Kahn Gillmor, Steve McIntyre, Guntupalli Karunakar, Jano Gulja , Karolina Kali , Ben Hutchings, Matej Kova i , Khoem Sokhem, Lisandro "I have the longest name in this list" Dami n Nicanor P rez-Meyer, Amanpreet Singh Alam, H ctor Or n, Hans Nordhaugn, Ivan Mas r, Dr. Tirumurti Vasudevan, John "yes, Kansas is as flat as you can imagine" Goerzen, Jean-Baptiste "Piwet" Perrier, Elizabeth "I love you" Perrier, Peter Eisentraut, Jesus "enemy by nature" Climent, Peter Palfrader, Vasudev Kamath, Miroslav "Chicky" Ku e, Mart n Ferrari, Ollivier Robert, Jure uhalev, Yunqiang Su, Jonathan McDowell, Sampada Nakhare, Nayan Nakhare, Dirk "rendez-vous for Chicago marathon" Eddelbuettel, Elian Myftiu, Tim Retout, Giuseppe Sacco, Changwoo Ryu, Pedro Ribeoro, Miguel "oh no, not him again" Figueiredo, Ana Guerrero, Aur lien Jarno, Kumar Appaiah, Arangel Angov, Faidon Liambotis, Mehdi Dogguy, Andrew Lee, Russ Allbery, Bj rn Steensrud, Mathieu Parent, Davide Viti, Steinar H. Gunderson, Kurt Gramlich, Vanja Cvelbar, Adam Conrad, Armi Be irovi , Nattie Mayer-Hutchings, Joerg "dis shuld be REJECTed" Jaspert and Luca Capello. Let's say it gain:

• Danke
• Thank you
• (RTL or not?) / toda
• Gracias
• / arigat
• / n ndi
• Obrigado
• Grazie
• C m n
• Kadin chey la
• / Efharisto
• Dank je wel
• Tak
• D ngge
• Merci
• Kiitos
• Tika hoki
• / dhanyavaadhamulu
• Thank you and God save the Queen
• Mul umesc
• Tack
• / didi madloba
• Gr cies
• Dakujem
• / Aabhar
• / Dhanyavadagalu
• Paldies
• / kop khun krap
• Terima kasih
• Hvala (hr)
• / Dhanyavad
• / Hvala (sr)
• Hvala (sl)
• / Akun
• / Sukriya
• Takk
• / Nandri
• Maki biyen jianbakik
• D kuji
• / Xiexie
• / Aabhari aahe
• Faleminderit
• / Kam sah ham ni da
• / Blagodaram
• / Xiexie
• Hvala (bs)

So Christian likes to give out awards for the best bug reporting estimates and also does statistics about developers per capita. I've got at least one area where he's on top:

The award for the introduction of the highest version into the archive goes to Nicolas Spalinger and Christian Perrier for ttf-sil-gentium. The use of a date as an epoch is amazing. The runner-up is Joey Hess with intercal (soon to be gone from Debian altogether), reusing the version number in the epoch. Somehow that fits with the crazy language the package contains.

The award for the most minimal version goes to Guido G nther with libvirt-glib. It's a number less than zero but still not negative. The runner-up is Raphael Geissert with switchsh which just happens to use 2007 as a checkout date.

I mentioned this briefly yesterday, but now I'll try to summarize the story of a great surprise and a big moment for me. All this started when my wife Elizabeth and my son Jean-Baptiste wanted to do something special for my 50th birthday. So, it indeed all started months ago, probably early March or something (I don't yet have all the details). Jean-Baptiste described this well on the web site, so I won't go again into details, but basically, this was about getting birthday wishes from my "free software family" in, as you might guess, as many languages as possible. Elizabeth brought the original idea and JB helped her by setting up the website and collecting e-mail addresses of people I usually work with: he grabbed addresses from PO files on Debian website, plus some in his own set of GPG signatures and here we go. And then he started poking dozens of you folks in order to get your wishes for this birthday. Gradually, contributions accumulated on the website, with many challenges for them: be sure to get as many people as possible, poking and re-poking all those FLOSS people who keep forgetting things... It seems that poking people is something that's probably in the Perrier's genes! And they were doing all this without me noticing. As usually in Debian, releasing on time is a no-no. So, it quickly turned out that having everything ready by April 2nd wouldn't be possible. So, their new goal was offering this to me on Pentecost Sunday, which was yesterday. And...here comes the gift. Aha, this looks like a photo album. Could it be a "50 years of Christian" album? But, EH, why is that pic of me, with the red Debconf5 tee-shirt (that features a world map) and a "bubulle" sign, in front of the book? But, EH EH EH, what the .... are doing these word by H0lger, then Fil, then Joey doing on the following pages? And only then, OMG, I discover the real gift they prepared. 106, often bilingual, wishes from 110 people (some were couples!). 18 postcards (one made of wood). 45 languages. One postcard with wishes from nearly every distro representatives at LinuxTag 2011. Dozens of photos from my friends all around the world. All this in a wonderful album. I can't tell what I said. Anyway, JB was shooting a video, so...we'll see. OK, I didn't cry...but it wasn't that far and emotion was really really intense. Guys, ladies, gentlemen, friends....it took me a while to realize what you contributed to. It took me the entire afternoon to realize the investment put by Elizabeth and JB (and JB's sisters support) into this. Yes, as many of you wrote, I have an awesome family and they really know how to share their love. I also have an awesome virtual family all around the world. Your words are wholeheartedly appreciated and some were indeed much much much appreciated. Of course, I'll have the book in Banja Luka so that you can see the result. I know (because JB and Elizabeth told me) that many of you were really awaiting to see how it would be received (yes, that includes you, in Germany, who I visited in early May!!!). Again, thank you so much for this incredible gift. Thank you Holger Levsen, Phil Hands, Joey Hess, Lior Kaplan, Martin Michlmayr, Alberto Gonzalez Iniesta, Kenshi "best friend" Muto, Praveen Arimbrathodiyil, Felipe Augusto van de Wiel, Ana Carolina Comandulli (5 postcards!), Stefano Zacchiroli (1st contribution received by JB, of course), Gunnar Wolf, Enriiiiiico Zini, Clytie Siddall, Frans Pop (by way of Clytie), Tenzin Dendup, Otavio Salvador, Neil McGovern, Konstantinos Margaritis, Luk Claes, Jonas Smedegaard, Pema Geyleg, Meike "sp tzle queen" Reichle, Alexander Reichle-Schmehl, Torsten Werner, "nette BSD" folks, CentOS Ralph and Brian, Fedora people, SUSE's Jan, Ubuntu's Lucia Tamara, Skolelinux' Paul, Rapha l Hertzog, Lars Wirzenius, Andrew McMillan (revenge in September!), Yasa Giridhar Appaji Nag (now I know my name in Telugu), Amaya Rodrigo, St phane Glondu, Martin Krafft, Jon "maddog" Hall (and God save the queen), Eddy Petri or, Daniel Nylander, Aiet Kolkhi, Andreas "die Katze geht in die K che, wunderbar" Tille, Paul "lets bend the elbow" Wise, Jordi "half-marathon in Banja Luka" Mallach, Steve "as ever-young as I am" Langasek, Obey Arthur Liu, YAMANE Hideki, Jaldhar H. Vyas, Vikram Vincent, Margarita "Bronx cross-country queen" Manterola, Patty Langasek, Aigars Mahinovs (finding a pic *with* you on it is tricky!), Thepittak Karoonboonyanan, Javier "nobody expects the Spanish inquisition" Fern ndez-Sanguino, Varun Hiremath, Moray Allan, David Moreno Garza, Ralf "marathon-man" Treinen, Arief S Fitrianto, Penny Leach, Adam D. Barrat, Wolfgang Martin Borgert, Christine "the mentee overtakes the mentor" Spang, Arjuna Rao Chevala, Gerfried "my best contradictor" Fuchs, Stefano Canepa, Samuel Thibault, Eloy "first samba maintainer" Par s, Josip Rodin, Daniel Kahn Gillmor, Steve McIntyre, Guntupalli Karunakar, Jano Gulja , Karolina Kali , Ben Hutchings, Matej Kova i , Khoem Sokhem, Lisandro "I have the longest name in this list" Dami n Nicanor P rez-Meyer, Amanpreet Singh Alam, H ctor Or n, Hans Nordhaugn, Ivan Mas r, Dr. Tirumurti Vasudevan, John "yes, Kansas is as flat as you can imagine" Goerzen, Jean-Baptiste "Piwet" Perrier, Elizabeth "I love you" Perrier, Peter Eisentraut, Jesus "enemy by nature" Climent, Peter Palfrader, Vasudev Kamath, Miroslav "Chicky" Ku e, Mart n Ferrari, Ollivier Robert, Jure uhalev, Yunqiang Su, Jonathan McDowell, Sampada Nakhare, Nayan Nakhare, Dirk "rendez-vous for Chicago marathon" Eddelbuettel, Elian Myftiu, Tim Retout, Giuseppe Sacco, Changwoo Ryu, Pedro Ribeoro, Miguel "oh no, not him again" Figueiredo, Ana Guerrero, Aur lien Jarno, Kumar Appaiah, Arangel Angov, Faidon Liambotis, Mehdi Dogguy, Andrew Lee, Russ Allbery, Bj rn Steensrud, Mathieu Parent, Davide Viti, Steinar H. Gunderson, Kurt Gramlich, Vanja Cvelbar, Adam Conrad, Armi Be irovi , Nattie Mayer-Hutchings, Joerg "dis shuld be REJECTed" Jaspert and Luca Capello. Let's say it gain:

• Danke
• Thank you
• (RTL or not?) / toda
• Gracias
• / arigat
• / n ndi
• Obrigado
• Grazie
• C m n
• Kadin chey la
• / Efharisto
• Dank je wel
• Tak
• D ngge
• Merci
• Kiitos
• Tika hoki
• / dhanyavaadhamulu
• Thank you and God save the Queen
• Mul umesc
• Tack
• / didi madloba
• Gr cies
• Dakujem
• / Aabhar li> / Dhanyavadagalu
• Paldies
• / kop khun krap
• Terima kasih
• Hvala (hr)
• / Dhanyavad
• / Hvala (sr)
• Hvala (sl)
• / Akun
• / Sukriya
• Takk
• / Nandri
• Maki biyen jianbakik
• D kuji
• / Xiexie
• / Aabhari aahe
• Faleminderit
• / Kam sah ham ni da
• / Blagodaram
• / Xiexie
• Hvala (bs)

In a recently published article, Paul Vixie, past author and architect of BIND, one of the most popular internet domain server, explains why DNS servers should use anycast for increased reliability and faster answers. The main argument against unicast is that some resolvers may not be smart enough to select the best server to query and therefore, they may select a server on the other side of the planet. Since, you cannot go faster than light, you get a penalty of about 100 milliseconds in this case.

Unicast & anycast Most addresses that you handle are unicast addresses, i.e. the address of a single receiver. Any time you send a packet to an unicast address, it will be forwarded to this single receiver. Another common network addressing system is multicast (which happens to include broadcast). When you send a packet to a multicast address, several receivers may get it. The packet is copied as needed by some nodes. Anycast addresses allow you to send a packet to a set of receivers but only one of them will receive it. The packet will not be copied. Usually, the idea behind anycast is that the packet is sent to the nearest receiver. There is no universal way to determine if an IP address is an unicast address or an anycast address just by looking at it. For example 192.5.5.241 is an anycast address while 78.47.78.132 is an unicast address. ISC, which maintains BIND, operates the F root domain server, one of the 13 Internet root name servers. This server is queried by using 192.5.5.241 IPv4 anycast address or 2001:500:2f::f IPv6 anycast address. ISC has published a document explaining how anycast works. Several nodes around the globe announces the same subnet using BGP. When one router running BGP has to send a query to the anycast address, it will have several choices in its BGP table. It will usually select the shortest path and route the query to the corresponding router. Some nodes may choose to restrict the announcement about the subnet containing the anycast address. They are called local nodes (by opposition to other global nodes). This allows them to serve query only from their clients and use cheaper connectivity and hardware.

Lab Let s play with anycast by setting up a lab to experiment with it. We want to setup an IPv6 anycast DNS service using two global nodes, G1 and G2, and one local node, L1. We build some kind of mini-Internet. See :

Setting up the lab This lab will use UML guests for all nodes. For more details on how this works, look at my previous article about network labs with User Mode Linux. You first need to grab the lab:

$ git clone https://vincentbernat@github.com/vincentbernat/network-lab.git
$ cd network-lab/lab-anycast-dns
$ ./setup

You will need to install the dependencies needed by the script on your host system. The script was tested on Debian unstable. If some of the dependencies do not exist in your distribution, if they don t behave as in Debian or if you don t want to install them on your host system, you can use debootstrap to create a working system:

$ sudo debootstrap sid ./sid-chroot http://ftp.debian.org/debian/
[...]
$ sudo chroot ./sid-chroot /bin/bash
# apt-get install iproute zsh aufs-tools
[...]
# apt-get install bird6
[...]
# exit
$ sudo mkdir -p ./sid-chroot/$HOME
$ sudo chown $(whoami) ./sid-chroot/$HOME
$ ROOT=./sid-chroot ./setup

We are running a lot of UML guests in this lab. We assign 64 MB to each host. UML guests do not use host memory until they need it but because of cache subsystem, you can expect that each guest will use 64 MB of memory. This means that you need about 2 GB of RAM to run this lab. Moreover, each guest will create a file representing its memory. Therefore, you need about 2 GB of free space in /tmp too. Routers are named after their AS number. The router of AS 64652 is just 64652. Paris, NewYork and Tokyo are the exception. The lab will use only one switch but we will use VLAN to create several L2 networks. Each link in our schema is an L2 network. Each link will get its own L3 network. Those networks are prefixed with 2001:db8:ffff:. Leaf AS have their own L3 network 2001:db8:X::/48 where X is the AS number minus 60000. Look at /etc/hosts on each host to get the IP of all hosts.

Mini-Internet routing AS 64600 is some kind of Tier-1 transit network (like Level 3 Communications). It has three points of presence: Paris, New York and Tokyo. AS 64650 is an European regional transit network, AS 64640 is an East Asian regional transit network and AS 64610, 64620 and 64630 are North American regional transit network which are peering each other. Other leaf AS are local ISP. This is not really what Internet looks like but shaping our lab like a tree allows us to not deal with a lot of BGP stuff: we ensure that the shortest path (in number of BGP hops) from one client to one server is the best path. Each BGP router will get a basic BGP configuration containing only the list of peers. Since Paris, Tokyo and NewYork are in the same AS, they will use iBGP. They are fully meshed for this purpose but this does not provide redundancy because iBGP routes are not redistributed inside iBGP. A more complex setup would be needed to provide redundancy inside AS 64600. We don t use an IGP inside leaf AS as we should: for the sake of simplicity, we redistribute directly connected routes into BGP. While in my previous lab, I used Quagga, I will use BIRD in this one. It is a more modern daemon with a clean design on how routing tables may interact. It also performs better. However, it lacks several features from Quagga. The configuration for BIRD is autogenerated from /etc/hosts. We use only one routing table inside BIRD. This table will be exported to the kernel and to any BGP instance. Some directly connected routes will be imported (those representing client networks) as well as all routes from BGP instances. Here is an excerpt of 64610 s configuration:

protocol direct  
   description "Client networks";
   import filter  
     if net ~ [ 2001:db8:4600::/40 40,48  ] then accept;
     reject;
    ;
   export none;
 
protocol kernel  
   persist;
   import none;
   export all;
 
protocol bgp  
   description "BGP with peer NewYork";
   local as 64610;
   neighbor 2001:db8:ffff:4600:4610::1 as 64600;
   gateway direct;
   hold time 30;
   export all;
   import all;
 

We do not export inter-router subnets to keep our routing tables small. This also means that those IP addresses are not routable in spite of the use of public IP addresses. Here is the routing table as seen by 64610 (use birdc6 to connect to BIRD):

bird> show route
2001:db8:4622::/48 via 2001:db8:ffff:4610:4620::2 on eth3 [bgp4 18:52] * (100) [AS64622i]
                   via 2001:db8:ffff:4600:4610::1 on eth0 [bgp1 18:52] (100) [AS64622i]
2001:db8:4621::/48 via 2001:db8:ffff:4610:4620::2 on eth3 [bgp4 18:52] * (100) [AS64621i]
                   via 2001:db8:ffff:4600:4610::1 on eth0 [bgp1 18:52] (100) [AS64621i]
2001:db8:4612::/48 via 2001:db8:ffff:4610:4612::2 on eth2 [bgp3 18:52] * (100) [AS64612i]
2001:db8:4611::/48 via 2001:db8:ffff:4610:4611::2 on eth1 [bgp2 18:52] * (100) [AS64611i]

As you can notice, it knows several paths to the same network, however, it only selects the best one (based on the length of the AS path):

bird> show route 2001:db8:4622::/48 all
2001:db8:4622::/48 via 2001:db8:ffff:4610:4620::2 on eth3 [bgp4 18:52] * (100) [AS64622i]
        Type: BGP unicast univ
        BGP.origin: IGP
        BGP.as_path: 64620 64622
        BGP.next_hop: 2001:db8:ffff:4610:4620::2 fe80::e05f:a3ff:fef2:f4e0
        BGP.local_pref: 100
                   via 2001:db8:ffff:4600:4610::1 on eth0 [bgp1 18:52] (100) [AS64622i]
        Type: BGP unicast univ
        BGP.origin: IGP
        BGP.as_path: 64600 64620 64622
        BGP.next_hop: 2001:db8:ffff:4600:4610::1 fe80::3426:63ff:fe5e:afbd
        BGP.local_pref: 100

Let s check that everything works with traceroute6 on C1:

# traceroute6 G2.lab
traceroute to G2.lab (2001:db8:4612::2:53), 30 hops max, 80 byte packets
 1  64652-eth1.lab (2001:db8:4652::1)  -338.277 ms  -338.449 ms  -338.502 ms
 2  64650-eth2.lab (2001:db8:ffff:4650:4652::1)  -338.324 ms  -338.363 ms  -338.384 ms
 3  Paris-eth2.lab (2001:db8:ffff:4600:4650::1)  -338.191 ms  -338.329 ms  -338.282 ms
 4  NewYork-eth0.lab (2001:db8:ffff:4600:4600:1:0:2)  -338.144 ms  -338.182 ms  -338.235 ms
 5  64610-eth0.lab (2001:db8:ffff:4600:4610::2)  -338.078 ms  -337.958 ms  -337.944 ms
 6  64612-eth0.lab (2001:db8:ffff:4610:4612::2)  -337.778 ms  -338.103 ms  -338.041 ms
 7  G2.lab (2001:db8:4612::2:53)  -338.001 ms  -338.045 ms  -338.080 ms

Let s see what happens if we shut the link between NewYork and 64610. This link is VLAN 10. Since vde_switch does not allow to shut a port, we will change the VLAN of port 9 to VLAN 4093. After at most 30 seconds, the BGP session between NewYork and 64610 will be torn down and packets from C1 to G2 will take a new path:

# traceroute6 G2.lab
traceroute to G2.lab (2001:db8:4612::2:53), 30 hops max, 80 byte packets
 1  64652-eth1.lab (2001:db8:4652::1)  -338.382 ms  -338.499 ms  -338.503 ms
 2  64650-eth2.lab (2001:db8:ffff:4650:4652::1)  -338.284 ms  -338.317 ms  -338.151 ms
 3  Paris-eth2.lab (2001:db8:ffff:4600:4650::1)  -337.954 ms  -338.031 ms  -337.924 ms
 4  NewYork-eth0.lab (2001:db8:ffff:4600:4600:1:0:2)  -337.655 ms  -337.751 ms  -337.844 ms
 5  64620-eth0.lab (2001:db8:ffff:4600:4620::2)  -337.762 ms  -337.507 ms  -337.611 ms
 6  64610-eth3.lab (2001:db8:ffff:4610:4620::1)  -337.531 ms  -338.024 ms  -337.998 ms
 7  64612-eth0.lab (2001:db8:ffff:4610:4612::2)  -337.860 ms  -337.931 ms  -337.992 ms
 8  G2.lab (2001:db8:4612::2:53)  -337.863 ms  -337.768 ms  -337.808 ms

Setting up anycast DNS Our anycast DNS service has three nodes. Two global ones, located in Europe and North America and one local one targeted at customers of AS 64620 only. The IP address of this anycast DNS server is 2001:db8:aaaa::53/48. We assign this address to G1, G2 and L1. We also assign 2001:db8:aaaa::1/48 to 64651, 64612 and 64621. BIRD configuration is adapted to advertise this network:

protocol direct  
   description "Client networks";
   import filter  
     if net ~ [ 2001:db8:4600::/40 40,48  ] then accept;
     if net ~ [ 2001:db8:aaaa::/48 ] then accept;
     reject;
    ;
   export none;
 

We use NSD as a name server. This is an authoritative only name server. The configuration is pretty simple. We just ensure that it is bound to the IPv6 anycast address (otherwise, it may answer with the wrong address). The zone file is customized to answer the name of the server:

#(C1) host -t TXT example.com 2001:db8:aaaa::53
Using domain server:
Name: 2001:db8:aaaa::53
Address: 2001:db8:aaaa::53#53
Aliases:
example.com descriptive text "G1"
#(C5) host -t TXT example.com 2001:db8:aaaa::53
Using domain server:
Name: 2001:db8:aaaa::53
Address: 2001:db8:aaaa::53#53
Aliases:
example.com descriptive text "G2"

If we try from C3, we may be redirected to L1 while we are not a customer of AS 64620. A common way to handle this is to let 64621 tag the route with a special community that will let know 64620 that the route should not be exported.

protocol direct  
   description "Client networks";
   import filter  
     if net ~ [ 2001:db8:4600::/40 40,48  ] then accept;
     if net ~ [ 2001:db8:aaaa::/48 ] then  
          bgp_community.add((65535,65281));
          accept;
      
     reject;
    ;
   export none;
 

The community used is known as the no-export community. BIRD knows how to handle it. However, we hit here some limitations of BIRD:

1. The correct way to let 64622 knows about this route is to build a BGP confederation for AS 64620 and let AS 64622 and AS 64621 be part of it. This means that those three AS will be seen as AS 64200 from outside of the confederation. Moreover, the no-export community would allow to export the route only within the confederation. This is exactly what we need but BIRD does not support confederations.
2. BIRD first selects the best route to export then apply filtering. This means that even if 64620 knows non-filtered route to 2001:db8:aaaa::/48, it will select the route to L1, filter it out and export nothing to 64622.

Therefore, we need to fallback to ask BIRD to not export the route to AS 64600, 64610 and 64630 on 64620. We could use a special community to filter out the route but we keep it simple and just filter the route directly.

filter keep_local_dns  
   if net ~ [ 2001:db8:aaaa::/48 ] then reject;
   accept;
 
protocol bgp  
   description "BGP with peer NewYork";
   local as 64620;
   neighbor 2001:db8:ffff:4600:4620::1 as 64600;
   gateway direct;
   hold time 30;
   export filter keep_local_dns;
   import all;
 

Voil . Only C4 will be able to query L1. If AS 64621 is missing, it will query G2 instead. One major point about anycast is to know that redundancy is done at the AS level only. If the name server on L1 does not work correctly, requests will still be routed to it. Therefore, with anycast, you still need to provide redundancy inside each AS (or stop advertising the anycast network as soon as there is a failure).

Beyond DNS Anycast can be used to serve HTTP requests too. This is less commonly used because your connection may be rerouted to another node while it is still running. This is not a problem with DNS because there is no connection (you send a query, you receive an answer). There are at least two CDN (MaxCDN and CacheFly) which uses anycast to ensure low roundtrip time and very high reliability. Setting up an HTTP server with an anycast address is no different than setting up a DNS server. However, you need to ensure maximum stability of the routing path to avoid the connection to be dropped while running. I suppose that this is done by hiring some high-level BGP expert. You can also mix unicast and anycast:

• anycast DNS answers the IP address of a nearby unicast HTTP server, or
• anycast DNS answers the IP address of an anycast HTTP server that will issue a redirect to an unicast HTTP server when downloading or streaming large files.