Search Results: "spa"

5 March 2013

Michal Čihař: phpMyAdmin translations status

Next round of phpMyAdmin 4.0 translation status report is coming. So let's look at which translations are at 100% right now (some changes this week due to new strings to translate): Almost complete: As you can see, there is still lot of languages missing, this might be your opportunity to contribute to phpMyAdmin. Also you are welcome to translate phpMyAdmin 4.0 using translation server. If your language is already fully translated and you want to help as well, you can translate our documentation as well.

Filed under: English Phpmyadmin 0 comments Flattr this!

Debian Med: Debian Med sprint report (by Andreas Tille)

This is the report about my work at Debian Med sprint ten days ago in Sch nberger Strand. If you are interested in Sprints in general you might be interested in work item 2. below.
  1. Wrote draft article for Indian health care magazin. If you might like to proofread the article I'd be very happy (it is not yet to late for changes.) There is also a PDF version.
  2. I have given a short talk proving the importance of sprints. The slides are basically graphs and I try to prove that sprints are a really good idea. The background knowledge is that the Debian Med team is doing sprints since 2011 and looking at all graphs you can see that this has a really positive effect. Thanks to Debian and its sponsors for supporting this kind of sprints.
  3. Packaging
    • Worked with T. Travis on flexbar and uploaded the package to new queue
    • Worked with Ch. Gille on strap-base and uploaded the package to new queue
    • Discussed strategy how to strip glam2 source from meme upstream with T. Booth. Meme upstream agreed to keep the original license of Glam2 and backport the changes from Meme source archive
    • Discussed igv packaging issues with O. Sallou who updated the package and documented some issues about its dependency goby
    • Worked together with I. Maintz on cellprofiler
    • Worked together with I. Maintz on a couple of R packages which are mostly predependencies but also one Debian Med primary target (r-cran-boolnet) was uploaded to new
  4. Discussing / chatting
    • Some chat with Ch. Steigies (Debian Games, Debian m68k, Debian Science)
    • Discussion with M. Banck about DebiChem
  5. Little bit of MoM mentoring
  6. Maintain Debian Med tasks files about newly commited packages of other sprint participants
  7. General infrastucture issues
    • Issues with machine-readable files importer into UDD
    • Try to revive PET data in UDD
    • Work on installation of future blends.debian.net host (install needed packages, create UDD clone)
Thanks to all participants of the sprint and specifically to Steffen M ller who took over the work of organising. It was fun to meet you all and I'm even looking right now forward to the next sprint hopefully beeing able to continue the graphing of positive results of sprints in our team metrics.
We had some nice food, not so nice weather and from my perspective the only drawback was that at home there would have been perfect conditions for skiing ... but finally there are preferences. ;-)
See you at next sprint!

Lisandro Damián Nicanor Pérez Meyer: My Debian freeze experience (so far)

This is the first freeze in which I'm involved with upload rights. And it turned out to be a quite interesting ride so far, so I thought it would be nice to write about it.

As some of you may know, I'm a part of the Qt/KDE team. Before the freeze I was mostly involved in leaf packages, with some patch here or there, nothing fancy. And then the freeze came...

Bugs in Qt

...and bugs appeared in Qt. But they didn't get solved, even if the patches were there. Due to personal reasons, the manpower in Qt/KDE land decreased below normal levels (which were already low).

I took the time to review them, apply them in a local branch, build and test the fixes. I did a Qt upload before, but it was a team-consented one. This time there was not much reaction in our IRC channel as it used to be, so I was doubting if going ahead or not. I asked Ana, my great friend and former sponsor, for an opinion on the subject, and she gave me a really important advice: the patches were looking good and there is one really big true: if something get's broken, it can be fixed with a later upload.

You might be asking yourself why I was that afraid of doing the upload. Well, when one maintains such a medular package for many users one has to be careful And I also got used that those "big ones" like Qt where normally handled by hand skilled people. Do not take me wrong here, it's not that those people where keeping them for themselves, it's knowing that one does not has the same skills nor experience as them.

But again, no one was able to upload and I had the chance and will to do another upload if needed, so off it went. That was Qt 4:4.8.2-2.

Then new experiences followed: asking a buildd maintainer for a giveback, asking the Release Team for an unblock (more on this later), etc. While sponsoring me, Ana gave me another excellent advice which I always keep in my mind:

You can't know **everything** about Debian.

And that also includes a not so technical skill: communicating with other teams. But finally we got this new version of Qt in testing. Cool :-)

Of course, new bugs appeared, and my lack of skills (and sometimes, time) where replaced by team work: Pino looking at patches and Sune contacting upstream. The eleven uploads that followed are a nice example of team work, even if I was the one who signed and did the uploads. Whoever uses Qt must know that these wonderful people (including those who are not so active nowadays like Modestas or Fathi) have done lots to bring the better to their users.Thank you guys!

Be careful, they might bite you back!

Coming back to the non-technical skills, sometimes you have to communicate with other teams in Debian. And each team is (naturally) a separate world: possibly different people, different goals, etc. Of course, we share the goal to make Debian the best experience we can, but we do not necessarily agree on the paths to achieve so.

During the freeze, there is a team that gets lots of pressure, and not by chance: the Release Team. They handle a very important task, which is to ride the freeze to get to a release. OK, that's what everyone knows. Now, one thing is knowing that and another is really understanding what does that means.

Of course I was in the first group. From the outside, communicating with the RT was a kind of "special art", and not an easy one. I have even been advised to not ask for more than one or two unblocks per weekend, as they might "bite me back". So I put on my flamesuit on and... launched reportbug release.debian.org.

Now I'm really happy to say that my experience was far from what I described above. And yes, I had the chance to even disagree on some stuff. But remember: non-technical skills, a.k.a. social skills. Once I started to know what was going on inside the RT (joining #debian-release was a big help for that) I learnt some nice tips to approach them. Please allow me to list some of them:

  • Remember: you are the maintainer of the package, they are like gatekeepers that are there to help us coordinate to do a release. But they don't maintain the code, you do that. So try to be verbose when needed, explain the changes and don't forget a nice diff. They need to understand what is going on: they can't read your mind.
  • They are human beings too: not everyday might be their best day (the same goes for you too!). And they are under the pressure of a release. Be patient, that finally pays off.
  • Does your changes seem not so clear? try to improve them.
  • The package has a lot of changes but you really feel they are needed? Try to explain that as good as you can.
  • Try to put yourself in their position: do we really want this? If in doubt, there is a nice way to know what they think: a pre-approval bug.
I want to make a stop in this last point. A pre-approval bug it's an unblock bug in which you edit the subject to add "pre-approval" in it. Easy, isn't it? It gives you the opportunity to know what the RT thinks before doing the upload. In other words: it gives you the chance to communicate and do things in the best possible way for all the parts involved.

I've have also seen pre-approval bugs that were really not needed. But to learn where the threshold of what can be directly uploaded and what deserves a pre-approval bug is you need to know the guidelines the RT gives you. Do you still have doubts? fire a pre-approval bug and try to be clear.

Of course, this are all fruits of my experience with the RT during this time. If the RT thinks different from what I'm writing here, please stand up: we are hear to listen to you and learn :-)

As a side note, I think I should file a wishlist bug to include the pre-approval bug option in reportbug. Yes, I'm lazy :-)

Summing up

Overall this was a very nice and positive experience. We are not done yet. Are we really done at some point? Let's hope not, because this is where the fun comes from :-)

4 March 2013

Michal Čihař: Nice OpenStreetMap project

For quite some time, I'm contributing to OpenStreetMap. Mostly covering areas where I live or I know well, but sometime I randomly update areas where I travel as well. The one important bit was always missing for me - nice frontend to render many of hidden features. Now this space seems to be slowly filled in by map1.eu. This quite new project (first announcement has been two weeks ago) renders quite nice maps for Europe. The map is primarily intended for hiking or cycling, so it includes things like hiking routes or cycle routes. In Czech republic we have quite great maps on mapy.cz, but I don't know anything what covers whole Europe. The project still has some issues, but is progressing nicely as you can see in today's announcement of 0.2 release (in Czech). Of course you can help, either by code or by money, which is needed to run rendering servers.

Filed under: English Maps 0 comments Flattr this!

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.

Lucas Nussbaum: DPL game

When Francesca started her DPL game, I too started think about possible candidates. Here is my shortlist of dream candidates: Seriously, if you are a DD, you have the right to run. There s no need for someone to nominate you. If you think that you could possibly say something interesting during the discussion period, and can spare the time to participate in the -vote@ discussions, please run. DPL campaigns used to be a great time where Debian visions, goals, politics and random stuff were discussed. The more candidates, the more interesting campaigns (8 candidates in 2007!). Also, there are already two three other candidates, so even if you don t want the job, it s not that risky. (Initially, I thought about nominating everyone, but security-wise, it might not be such a great idea.)

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

Philipp Kern: PSA: LVM, pvmove and SSDs

If you use LVM with Wheezy on a solid-state drive, you really want to install the latest lvm2 update (i.e. 2.02.95-6, which contains the changes of -5). Otherwise, if you set issue_discards=1 in /etc/lvm/lvm.conf, you will experience severe data loss when using pvmove. Happened to me twice, once I didn't care (chroot data being lost), the second time (today) I did. Not fun, especially when the backup of the data was scheduled for the same day.

One has to wonder why it takes three months for a bug that trashes data to reach testing. (Obviously I know the answer, but they're not particularly good reasons.) Other distributions, like Ubuntu, were much quicker to notice and incorporate that fix. And in the case of the named distribution not because they auto-synced it from unstable. If somebody notices such a grave bug, please yell at people to get the fix out there to our users. Thanks.

Bastian Blank: LDAP, Insignificant Space and Postfix

For some, LDAP, just like X.500, is black magic. I won't argue against. Sometimes it really shows surprising behavior. It always makes sense, if you think about what LDAP is built for. One surprising behavior is the handling of the "Insignificant Space"
LDAP supports syntax and comparator methods. The syntax specifies how the entry should look. Usually this is some form of text, but numbers or stuff like telephone numbers are supported as well. The comparators specifies how the values are compared. Most of the text comparators are defined to apply the handling of insignificant spaces. Insignificant space handling normalizes the use of spaces. First all leading and trailing spaces are removed. All the internal spaces are normalized to at most two spaces. At the end all strings starts and ends with one space to allow proper sub-string matches. The resulting strings are used for comparisons. This behavior makes sense most of the time. If the user want to find something in the directory, he usually don't cares about spaces, but about content. But I found one occurrence where this produces some grieve. Postfix supports LDAP since some time. And lets say, it does not care about spaces in its queries. This is no problem as e-mail addresses do not contain spaces. Or do they?
Yes, e-mail addresses can contain spaces. This is not widely known, but still allowed. This addresses are quoted and the command looks like RCPT TO:<" test"@example.com>. The local part is quoted and contains a space at the beginning. And this is where the problem starts. Postfix sanitizes the address. It uses a simplified internal representation of the address for all lookups. So the address gets test@example.com. This form is used in all table lookups. The LDAP table uses the internal form of the address. This address is copied verbatim into the query. This query may look this way (mail= test@example.com). It is sent to the server this way. The LDAP server applies the insignificant space modifications. The query is now interpreted and the comparator specified modifications are applied. The query gets effectively changed to (mail=test@example.com). And this is where the fun starts. Postfix accepts undeliverable mails. Depending on the setup, such LDAP queries may be used to check for valid addresses. Because of the space handling, the sender can add spaces to the beginning of the address and it will still be considered valid. In later steps this addresses are not longer valid. Addresses starting with spaces are considered invalid in some locations of Postfix. What surprised me a bit is that virtual alias handling did not map them. The unmodified addressed showed up on the LMTP backend server. That's why they showed up my radar. I would say Postfix is wrong in this case. The LDAP server applies the spec correctly and defines spaces in e-mail addresses as insignificant. Postfix on the other side considers them significant. The easiest fix would be to not allow any spaces in the LDAP table.

1 March 2013

Joerg Jaspert: tmux - like screen, just nicer. Replacing clusterssh too.

By now I am a long time happy user of tmux instead of screen. I started using it somewhere in 2011 and by now I only have one usage of screen left over (direct ttyS0 access for one serial). As usual I have a custom config for it, and if you are interested there is a link for you: tmux.conf. But the more interesting part and why I blog is that I also wrote a little helper around tmux. Ingeniously called tm. And a colleague said I should let other people use it too and place it somewhere accessible. So, err, here it is. Or better, the usage output of it, the actual script has a link somewhere below.
tmux helper by Joerg Jaspert <joerg@ganneff.de>
Call as: tm CMD [host]...
CMD is one of
 ls          List running sessions
 s           Open ssh session to host
 ms          Open multi ssh sessions to hosts, synchronizing input
 $anything   Either plain tmux session with name of $anything or
             session according to TMDIR file
TMDIR file:
Each file in $TMDIR defines a tmux session.
Filename is the commandline option $anything
Content is defined as:
  First line: Session name
  Second line: extra tmux options
  Any following line: A hostname to open a shell with in the normal
  ssh syntax. (ie [user@]hostname)
Environment variables recognized by this script:
TMPDIR - Where tmux stores its session information
         DEFAULT: If unset: /tmp
TMSORT - Should ms sort the hostnames, so it always opens the same
         session, no matter in which order hostnames are presented
         DEFAULT: true
TMOPTS - Extra options to give to the tmux call
         Note that this ONLY affects the final tmux call to attach
         to the session, not to the earlier ones creating it
         DEFAULT: -2
TMDIR  - Where are session information files stored
         DEFAULT: $ HOME /.tmux.d
TMWIN  - Where does your tmux starts numbering its windows?
         This script tries to find the information in your config,
         but as it only checks $HOME/.tmux.conf it might fail.
         So if your window numbers start at anything different to 0,
         like mine do at 1, then you can set TMWIN to 1

It is mainly useful for using tmux as a ssh-multiplexer and replacement for clusterssh though its happy to do any other tmux session too. As the help text may already have told you, you can use it to list existing tmux sessions (oh, wow!). Honestly, that one is there because tm ls is shorter than tmux ls More interestingly, tm s HOSTNAME opens a tmux session with the first window being a ssh shell to HOSTNAME. Should you later type tm s HOSTNAME again, it will attach to the existing session. But the real kicker for me (and colleagues) actually is the ms subcommand of it. ms being short for multi-session, it is my way of no-longer using clusterssh. Basically you type tm ms HOST1 user@HOST2 and it opens a session with one tmux window consisting of two panes. Showing you host1 and host2 at the same time. And the input to both is synchronized, that is - all your input is send to both of them. You aren t limited to just two hosts, do as many as you wish. Actually, I have no idea if tmux has an upper limit, but I did already have more than 100 hosts open at once. The major limitation there is not tmux - but simply the available screenspace, as all hosts are shown in ONE window! (The one advantage of clusterssh, it uses one xterm per host) This is quite helpful in all kinds of administration work involving clusters - imaging installing a package on 5 hosts of a cluster, you usually want it on all of them - or any kind of situations where one wants to run one command on many systems. As I m already said, I m lazy. And so there is a way to easily define multisessions that one uses regulary, by creating files inside the directory behind $TMDIR, usually $ HOME /.tmux.d. They are simple text files and let you easily define sessions you can then (re)open with a simple tm whateveritsname. And if you want the whole script by now: tm

Daniel Pocock: Monitoring JBoss, Tomcat and other application servers with JMXetric

JMXetric 1.0 was finally released in February, let's have a quick look at how conveniently it can be integrated with an application server. A more thorough analysis of gmetric4j and JMXetric can be found in the sections I contributed to the new O'Reilly book Monitoring with Ganglia General comments about JVM instrumentation and the JVM boot classpath Monitoring agents (there are a number of them out there) are loaded at an early stage by the JVM and it needs to have access to any of their dependencies through the boot classpath. JMXetric explicitly declares it's dependencies in MANIFEST.MF:
Boot-Class-Path: oncrpc-1.0.7.jar gmetric4j-1.0.2.jar
As no absolute path is specified, the JVM will look for those JARs in the same directory where the jmxetric.jar is located. Furthermore, the JVM will expect the exact filenames to match. If other filenames are used (e.g. for a newer version of gmetric), then the JVM command line needs to specify the filenames and locations, for example:
-Xbootclasspath/a:/opt/ganglia/jmxetric/gmetric4j-1.0.3.jar
Starting JBoss 7 with JMXetric To start with, unpack a vanilla JBoss distribution:
$ mkdir ~/opt
$ cd ~/opt
$ tar xzf ~/Downloads/jboss-as-7.1.0.Final.tar.gz
Now get the JMXetric code and put it, together with dependencies, in the same directory:
$ mkdir -p ~/opt/ganglia/jmxetric
$ cd ~/opt/ganglia/jmxetric
$ wget http://search.maven.org/remotecontent?filepath=info/ganglia/jmxetric/jmxetric/1.0.2/jmxetric-1.0.2.jar
$ wget http://search.maven.org/remotecontent?filepath=info/ganglia/gmetric4j/gmetric4j/1.0.2/gmetric4j-1.0.2.jar
$ wget http://search.maven.org/remotecontent?filepath=org/acplt/oncrpc/1.0.7/oncrpc-1.0.7.jar
Set up a config file for JMXetric:
$ mkdir -p ~/opt/ganglia/jmxetric/etc
$ cd ~/opt/ganglia/jmxetric/etc
$ wget https://raw.github.com/ganglia/jmxetric/master/etc/jmxetric.xml
$ cp jmxetric.xml jmxetric-jboss.xml
$ vi jmxetric-jboss.xml
and insert the following code:
                <!-- report web server request count -->
		<mbean name="jboss.as:subsystem=web,connector=http" pname="http">
			<attribute name="requestCount" type="int32"/>
		</mbean>
Finally, tell JBoss about the agent:
$ cd ~/opt/jboss-as-7.1.0.Final
$ vi bin/standalone.conf
and apply the following changes to standalone.conf:
--- bin/standalone.conf
+++ ../jboss-as-7.1.0.Final.for-jmxetric/bin/standalone.conf
@@ -4,6 +4,7 @@
 ##                                                                          ##
 ##############################################################################
 
+JBOSS_MODULES_SYSTEM_PKGS="org.jboss.logmanager"
 #
 # This file is optional; it may be removed if not needed.
 #
@@ -48,6 +49,8 @@
 #
 if [ "x$JAVA_OPTS" = "x" ]; then
    JAVA_OPTS="-Xms64m -Xmx512m -XX:MaxPermSize=256m -Djava.net.preferIPv4Stack=true -Dorg.jboss.resolver.warning=true -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000"
+   JAVA_OPTS="$JAVA_OPTS -Djava.util.logging.manager=org.jboss.logmanager.LogManager -Xbootclasspath/p:$JBOSS_HOME/modules/org/jboss/logmanager/main/jboss-logmanager-1.2.2.GA.jar -Xbootclasspath/p:$JBOSS_HOME/modules/org/jboss/logmanager/log4j/main/jboss-logmanager-log4j-1.0.0.GA.jar -Xbootclasspath/p:$JBOSS_HOME/modules/org/apache/log4j/main/log4j-1.2.16.jar"
+   JAVA_OPTS="$JAVA_OPTS -javaagent:$HOME/opt/ganglia/jmxetric/jmxetric-1.0.2.jar=host=jboss-host.example.org,port=8649,wireformat31x=true,config=$HOME/opt/ganglia/jmxetric/etc/jmxetric-jboss.xml"
    JAVA_OPTS="$JAVA_OPTS -Djboss.modules.system.pkgs=$JBOSS_MODULES_SYSTEM_PKGS -Djava.awt.headless=true"
    JAVA_OPTS="$JAVA_OPTS -Djboss.server.default.config=standalone.xml"
 else
Note that we are adding some of the core JBoss logging code to the boot classpath - that is because JMXetric depends on the logger, and like many monitoring agents, it is impacted by JBoss bug AS-3681. Adding these extra classpath settings is the workaround. Now go ahead and start JBoss, you should see a log message informing you that JMXetric is operational:
$ cd ~/opt/jboss-as-7.1.0.Final
$ chmod a+x bin/*.sh
$ bin/standalone.sh
=========================================================================
  JBoss Bootstrap Environment
  JBOSS_HOME: ...
.
.
.
=========================================================================
JMXetricAgent instrumented JVM, see https://github.com/ganglia/jmxetric
12:59:34,395 INFO  [info.ganglia.gmetric4j.GMonitor] Setting up 1 samplers
12:59:34,536 INFO  [org.jboss.modules] JBoss Modules version 1.1.1.GA
12:59:34,617 INFO  [org.jboss.msc] JBoss MSC version 1.0.2.GA
12:59:34,653 INFO  [org.jboss.as] JBAS015899: JBoss AS 7.1.0.Final "Thunder" starting
.
.
.
I hope this example is useful for you. Please feel free to share recipes you develop for collecting useful JVM metrics, and also any custom charts/reports through collaboration with the Ganglia community mailing list, the Ganglia wiki or your own blog.

Ritesh Raj Sarraf: I am so indebted to the community

As someone who learned computers on his own, I always acknowledged the value that the Free Software movement has brought. The accessibility of these topics, which are only supposed to be part of text books and schools, is available for anyone and everyone who has the resource and passion to do it. But this past week, 2 things made me pretty impressed with the maturity and quality of work that we do.

rrs@zan:/media$ sudo lvextend -r -v -L 100G /dev/BackupDisk/DATA

Finding volume group BackupDisk
Executing: fsadm --verbose check /dev/BackupDisk/DATA
fsadm: "ext4" filesystem found on "/dev/mapper/BackupDisk-DATA"
fsadm: Skipping filesystem check for device "/dev/mapper/BackupDisk-DATA" as the filesystem is mounted on /media/DATA
fsadm failed: 3
Archiving volume group "BackupDisk" metadata (seqno 7).
Extending logical volume DATA to 100.00 GiB
Found volume group "BackupDisk"
Found volume group "BackupDisk"
Loading BackupDisk-DATA table (254:2)
Suspending BackupDisk-DATA (254:2) with device flush
Found volume group "BackupDisk"
Resuming BackupDisk-DATA (254:2)
Creating volume group backup "/etc/lvm/backup/BackupDisk" (seqno 8).
Logical volume DATA successfully resized
Executing: fsadm --verbose resize /dev/BackupDisk/DATA 104857600K
fsadm: "ext4" filesystem found on "/dev/mapper/BackupDisk-DATA"
fsadm: Device "/dev/mapper/BackupDisk-DATA" size is 107374182400 bytes
fsadm: Parsing tune2fs -l "/dev/mapper/BackupDisk-DATA"
fsadm: Resizing filesystem on device "/dev/mapper/BackupDisk-DATA" to 107374182400 bytes (13107200 -> 26214400 blocks of 4096 bytes)
fsadm: Executing resize2fs /dev/mapper/BackupDisk-DATA 26214400
resize2fs 1.42.5 (29-Jul-2012)
Filesystem at /dev/mapper/BackupDisk-DATA is mounted on /media/DATA; on-line resizing required
old_desc_blocks = 4, new_desc_blocks = 7
The filesystem on /dev/mapper/BackupDisk-DATA is now 26214400 blocks long.
I didn't have much hope that this extend operation would succeed. But it did. When I initiated this operation, in the background, I had the backups being synced parallely (which actually made me resize my volume. :-)
The other item which made me happy yesterday was Audacity. Once upon a time, when I needed to split a music file to cut a ringtone out of it, I'd go looking for software that could do it. Then I would hope that one of those software vendors have a fully working version and not a demo with just 5 seconds clipping. Cowon was one media player I can recollect I've used to split audio files.
But in this case, I had a different requirement. I needed to increase the dB of my ringtone file so that it sounded really a ringtone (Example: Bourne Ultimatum OST). Audacity, not only did it do the job, it did it for me in just 3-5 minutes. And all with just button clicks. For a n00b with no experience in that domain, I was really impressed.

28 February 2013

Gunnar Wolf: Dkg: Unwrap it with Blender. And ask @octagesimal / @casyopea !

Daniel tells his story building a wooly mammoth, and throws some ideas on how this could be implemented easily with free software. But if I read his post correctly, Daniel still misses the precise ways to do it. Our friends Octavio and Claudia (twitted hereby) have given some Blender courses here at our classroom at home (Guys! Come again! We miss you!), and host the Spanish-speaking g-blender community. At one of their courses, they showed how to model an object/character, and in order to color/texture its parts, you can unwrap it This process yields a flattened image with the surfaces that build your object, that you can then color. Well, you can also use it as a base pattern to cut and sew your plush! It is not meant to be used for this (although it works), so it won't give you the extra tabs to be sewn in place, and the joints might not be at the most comfortable places. But it is base you can work from.

27 February 2013

Petter Reinholdtsen: Dr. Richard Stallman, founder of Free Software Foundation, give a talk in Oslo March 1st 2013

Dr. Richard Stallman, founder of Free Software Foundation, is giving a talk in Oslo March 1st 2013 17:00 to 19:00. The event is public and organised by Norwegian Unix Users Group (NUUG) (where I am the chair of the board) and The Norwegian Open Source Competence Center. The title of the talk is The Free Software Movement and GNU , with this description:
The Free Software Movement campaigns for computer users' freedom to cooperate and control their own computing. The Free Software Movement developed the GNU operating system, typically used together with the kernel Linux, specifically to make these freedoms possible.
The meeting is open for everyone. Due to space limitations, the doors opens for NUUG members at 16:15, and everyone else at 16:45. I am really curious how many will show up. See the event page for the location details.

Matthew Garrett: Supporting third-party keys in a Secure Boot world

It's fairly straightforward to boot a UEFI Secure Boot system using something like Shim or the Linux Foundation's loader, and for distributions using either the LF loader or the generic version of Shim that's pretty much all you need to care about. The physically-present end user has had to explicitly install new keys or hashes, and that means that you no longer need to care about Microsoft's security policies or (assuming there's no exploitable flaws in the bootloader itself) fear any kind of revocation.

But what about if you're a distribution that cares about booting without the user having to install keys? There's several reasons to want that (convenience for naive users, ability to netboot, that kind of thing), but it has the downside that your system can now be used as an attack vector against other operating systems. Do you care about that? It depends how you weigh the risks. First, someone would have to use your system to attack another. Second, Microsoft would have to care enough to revoke your signature. The first hasn't happened yet, so we have no real idea how likely the second is. However, it doesn't seem awfully unlikely that Microsoft would be willing to revoke a distribution signature if that distribution were being used to attack Windows.

How do you avoid that scenario? There's various bits of security work you need to do, but one of them is to require that all your kernel modules be signed. That's easy for the modules in the distribution, since you just sign them all before shipping them. But how about third party modules? There's three main options here:

  1. Don't support third party modules on Secure Boot systems
  2. Have the distribution sign the modules
  3. Have the vendor sign the modules

The first option is easy, but not likely to please users. Or hardware vendors. Not ideal.

The second option is irritating for a bunch of reasons, and a pretty significant one is license-related. If you sign a module, does that mean you're endorsing it in some way? Does signing the nvidia driver mean that you think there's no license concerns? Even ignoring that, how do you decide whose drivers to sign? We can probably assume that companies like AMD and nvidia are fairly reputable, but how about Honest John's Driver Emporium? Verifying someone's identity is astonishingly expensive to do a good job of yourself, and not hugely cheaper if you farm it out to a third party. It's also irritating for the driver vendor, who needs a separate signature for every distribution they support. So, while possible, this isn't an attractive solution.

The third option pushes the responsibility out to other people, and it's always nice to get other people to do work instead of you. The problem then is deciding whose keys you trust. You can push that off to the user, but it's not the friendliest solution. The alternative is to trust any keys that are signed with a trusted key. But what is a trusted key? Having the distribution sign keys just pushes us back to option (2) - you need to verify everyone's identity, and they need a separate signing key for every distribution they support. In an ideal world, there'd be a key that we already trust and which is owned by someone willing to sign things with it.

The good news is that such a key exists. The bad news is that it's owned by Microsoft.

The recent discussion on LKML was about a patchset that allowed the kernel to install new keys if they were inside a PE/COFF binary signed by a trusted key. It's worth emphasising that this patchset doesn't change the set of keys that the kernel trusts - the kernel trusts keys that are installed in your system firmware, so if your system firmware trusts the Microsoft key then your kernel already trusts the Microsoft key. The reasoning here is pretty straightforward. If your firmware trusts things signed by Microsoft, and if a bad person can get things signed by Microsoft, the bad person can already give you a package containing a backdoored bootloader. Letting them sign kernel modules doesn't alter the power they already have over your system. Microsoft will sign PE/COFF binaries, so a vendor would just have to sign up with Microsoft, pay $99 to Symantec to get their ID verified, wrap their key in a PE/COFF binary and then get it signed by Microsoft. The kernel would see that this object was signed by a trusted key and extract and install the key.

Linus is, to put it mildly, unenthusiastic about this idea. It adds some extra complexity to the kernel in the form of a binary parser that would only be used to load keys from userspace, and the kernel already has an interface for that in the form of X509 certificates. The problem we have is that Microsoft won't sign X509 certificates, and there's no way to turn a PE/COFF signature into an X509 signature. Someone would have to re-sign the keys, which starts getting us back to option (2). One way around this would be to have an automated service that accepts PE/COFF objects, verifies that they're signed by Microsoft, extracts the key, re-signs it with a new private key and spits out an X509 certificate. That avoids having to add any new code to the kernel, but it means that there would have to be someone to run that service and it means that their public key would have to be trusted by the kernel by default.

Who would that third party be? The logical choice might be the Linux Foundation, but since we have members of the Linux Foundation Technical Advisory Board saying that they think module signing is unnecessary and that there's no real risk of revocation, it doesn't seem likely that they'll be enthusiastic. A distribution could do it, but there'd be arguments about putting one distribution in a more privileged position than others. So far, nobody's stood up to do this.

A possible outcome is that the distributions who care about signed modules will all just carry this patchset anyway, and the ones who don't won't. That's probably going to be interpreted by many as giving too much responsibility to Microsoft, but it's worth emphasising that these patches change nothing in that respect - if your firmware trusts Microsoft, you already trust Microsoft. If your firmware doesn't trust Microsoft, these patches will not cause your kernel to trust Microsoft. If you've set up your own chain of trust instead, anything signed by Microsoft will be rejected.

What's next? It wouldn't surprise me too much if nothing happens until someone demonstrates how to use a signed Linux system to attack Windows. Microsoft's response to that will probably determine whether anyone ends up caring.

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25 February 2013

Francesca Ciceri: Three Harry Potter crossovers you want to read

...at least, if you are into fan fictions and Harry Potter. I love fan fictions, and I'll shamelessly admit that I like Harry Potter too, but I usually avoid crossovers. That is because however interesting and exciting is - in theory - to have your favourite characters from different fandoms together, it often ends bad. So, it's a public duty of every fanfic reader to recommend good crossovers, if they stumble upon them. Here are some I found recently (all the quotes are from the stories' summaries). If you read any of these and want to talk about it or if you have more crossovers to recommend, drop me a mail. For more fan fiction recommendations, I suggest you to check this detailed index on tvtropes.org.

Russ Allbery: Review: The Hare with Amber Eyes

Review: The Hare with Amber Eyes, by Edmund de Waal
Publisher: Farrar, Straus and Giroux
Copyright: 2010
ISBN: 0-374-10597-9
Format: Kindle
Pages: 351
A netsuke ( ) is a miniature sculpture, often made from ivory or boxwood, generally rounded and no larger than a matchbox. They were a part of Japanese clothing starting from the 17th century: traditional garments had no pockets, but people needed a way to carry small objects around with them, so they wore pouches or small boxes attached to a cord. The cord could then be passed under the sash of the garment and be held in place there by a netsuke attached to the end of the cord, since the netsuke was too large to slip under the sash. The hare with amber eyes is one of 264 netsuke. It, and all the rest, belonged to Edmund de Waal's uncle Iggie. They sat in a vitrine in his home in Japan, where de Waal went for a two-year scholarship and was working on a book on japonisme: the passionate and creative Western misunderstanding of Japan. When Iggie later died in 1991, de Waal inherited the collection. This book is his attempt to tell their history. The Hare with Amber Eyes falls into the genre of family memoir or biography, but it's one told from an unusual angle. Edmund de Waal is a potter by profession: an artist who creates physical objects that then pass from his studio out into the world. The physicality of the netsuke their occupation of time and space and their passsage through the world fascinates him, and he tries to express that fascination to the reader and uses it as a focal point for the memoir. He tells, here, the story of his own family, but he does so via the netsuke, following them from their purchase in Paris in 1871 through one branch of the family and then another until they reach Iggie and, finally, him. Along the way, he tries to put them into context. At first, the context is primarily artistic, and the early parts of this book are something of a tour of late 19th century artistic culture in Paris. But, as the story continues, the connection becomes more emotional and the context becomes more complicated. Anyone who is a fan of the TV program Antiques Roadshow or any similar effort to trace the history of specific objects will see the immediate appeal in this presentation. Antiques are fascinating in their mute path through lives and history; attempting to reconstruct the rooms they've sat in and the conversations they've witnessed is something I've always found intriguing. But it's also very difficult to do. Most of our objects, and most owners of objects, simply don't have that sort of documentation. I was wondering, at the start of this book, how de Waal was going to manage to construct his history. The answer is that his family is, or at least was, famous enough to have letters, papers, and history in libraries throughout Europe. That's what makes the parts of the book before Iggie's living memory possible. It's a bit disappointing, if unsurprising; de Waal doesn't have any special technique to find hidden history, and most objects could never have this sort of history written about them. The first owner of the netsuke in his family is Charles Ephrussi, a critic, historian, and art historian who was a patron of the Impressionists and who was important enough in Parisian art culture that he is the inspiration of a character in Marcel Proust's Remembrance of Things Past. This means that quite a lot of this book is about people who moved through social circles and lived in ways that I find quite foreign, which made it hard to invest too much in the first part of the book. The Ephrussi family was originally from Odessa and made a fortune as grain merchants some time prior to the start of the history, and by the time de Waal opens their story, they have vast inherited wealth. There is no sign in the book that Charles needs to work in any way. The first part of the book paints a picture of the culture of art patronage partly via descriptions of Charles's rooms and personal collection, to which the netsuke were added during the surge in interest in Japanese art in Europe produced by the opening of Japan during the Meiji period. It's interesting, but for me in a distant and intellectual way. (People with a deeper interest in Impressionist art or other late 19th century art may have a different reaction.) De Waal writes at length at the start of this book about avoiding sentimentality and trying to take an honest and immersive look at the history of the netsuke. The emotional intensity that he brings to this goal seemed a bit odd, since little in the early part of the book seems to tempt towards sentimentality. But then the Dreyfus Affair enters Charles's story, followed by his gift of the vitrine and the netsuke to a cousin in Austria as a marriage gift, and I started to realize the implications of following a possession of a prominent Jewish family in Europe during the first half of the twentieth century. This is the sort of non-fiction book that you can spoil, so I won't give a detailed description of the rest of the book. But there is a specific event in the history of the netsuke that de Waal tells that would be the story most people would start with, and I now understand the sentimentality that de Waal was trying to avoid. It's a great story, but one of the things I like about this book is that de Waal puts it into a broader context and complicates the story. He includes the long periods of time when the netsuke were mostly ignored, he ties them into the history of western obsession with (and exploitation of) Japanese art, and he shows how the sturdy nature of the netsuke, meant for physical handling rather than display, led to them creating the emotional connection that made them important to the family. It's a book that deals with anti-Semitism with accuracy and specifics without being either lurid or overwhelming. It's a book that traces a line through one of the most overwritten and well-trod areas of history and manages to stay on its own path. It's a book that made me angry, and made me cry, and then made me step back and think about those emotions in a broader context and think about the benefits of leaving those emotions behind. I've never read a book quite like this before. It's slow in places (particularly if one is not very interested in art history), utterly compelling in others, and carefully avoids any simple themes or grand stories. It's entangled with some of the darkest events of recent history, but de Waal stays tightly focused on the family through the lens of the netsuke, which is valuable for keeping the story from drifting into well-worn and less unique material. I was not as completely taken by this book as the review that got me to buy it (it's an excellent review, better than this one). But I'm glad that I read it, and I feel like I now know more about the world. Rating: 7 out of 10

24 February 2013

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.

Paul Tagliamonte: Here was a talk I gave at Boston Python a few weeks ago. Check...

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Here was a talk I gave at Boston Python a few weeks ago. Check it out, and feel free to follow along with the slides, and take a look at the source. Sorry about the major futzup at 40 minutes in, and small mistakes throughout first time giving this talk! (link to the video for those on the planets)

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