It has been a couple of months since my last GSoC update and a lot has happened since then. You can view the web interface at metrics.debian.net. There is a dynamic interface viewable with JavaScript enabled, and a static interface viewable with JS disabled. I am currently working on the dynamic interface. In the weeks since my last blog post I have accomplished a lot. There is support for pull and push metrics. Pull metrics run on the debmetrics server and pull data from some source. Push metrics run on a remote server and push data to the debmetrics server via HTTP POST. There is flask code and the static interface portion uses a general route, so that the flask code does not need to be modified every time a metric is added. There is a makefile that runs manifest2index.py and manifest2orm.py to generate the index page of the web interface and the SQLAlchemy model code respectively. I have a config file that allows the user to set the location of the manifest, pull_scripts, and graph_scripts directories. I have a debmetrics.wsgi file for easy deployment of debmetrics. There is a single layout.html that is the base layout for all the other pages. Nosetests is used for tests. Sphinx and readthedocs are used for the documentation. I wrote a minified_grabber script that downloads all the JS and css files that are not included with debmetrics itself. That helps make deployment easy. If you want to take a look at the code you can view the repository. I still have more work to do before the end of GSoC, mostly with the dynamic web interface and packaging of debmetrics. To keep up to date on my progress, you can either read this blog, or you can read the soc-corrdination mailing list.

In a comment on my post about Taxing Inferior Products [1] Ben pointed out that most crashes are due to software bugs. Both Ben and I work on the Debian project and have had significant experience of software causing system crashes for Debian users. But I still think that the widespread adoption of ECC RAM is a good first step towards improving the reliability of the computing infrastructure. Currently when software developers receive bug reports they always wonder whether the bug was caused by defective hardware. So when bugs can t be reproduced (or can t be reproduced in a way that matches the bug report) they often get put in a list of random crash reports and no further attention is paid to them. When a system has ECC RAM and a filesystem that uses checksums for all data and metadata we can have greater confidence that random bugs aren t due to hardware problems. For example if a user reports a file corruption bug they can t repeat that occurred when using the Ext3 filesystem on a typical desktop PC I ll wonder about the reliability of storage and RAM in their system. If however the same bug report came from someone who had ECC RAM and used the ZFS filesystem then I would be more likely to consider it a software bug. The current situation is that every part of a typical PC is unreliable. When a bug can be attributed to one of several pieces of hardware, the OS kernel and even malware (in the case of MS Windows) it s hard to know where to start in tracking down a bug. Most users have given up and accepted that crashing periodically is just what computers do. Even experienced Linux users sometimes give up on trying to track down bugs properly because it s sometimes very difficult to file a good bug report. For the typical computer user (who doesn t have the power that a skilled Linux user has) it s much worse, filing a bug report seems about as useful as praying. One of the features of ECC RAM is that the motherboard can inform the user (either at boot time, after a NMI reboot, or through system diagnostics) of the problem so it can be fixed. A feature of filesystems such as ZFS and BTRFS is that they can inform the user of drive corruption problems, sometimes before any data is lost. My recommendation of BTRFS in regard to system integrity does have a significant caveat, currently the system reliability decrease due to crashes outweighs the reliability increase due to checksums at this time. This isn t all bad because at least when BTRFS crashes you know what the problem is, and BTRFS is rapidly improving in this regard. When I discuss BTRFS in posts like this one I m considering the theoretical issues related to the design not the practical issues of software bugs. That said I ve twice had a BTRFS filesystem seriously corrupted by a faulty DIMM on a system without ECC RAM.

• [1] http://etbe.coker.com.au/2014/07/10/taxing-inferior-products/

Sociological Images has an interesting post by Jay Livingston PhD about a tennis final as a ritual [1]. The main point is that you can get a much better view of the match on your TV at home with more comfort and less inconvenience, so what you get for the price of the ticket (and all the effort of getting there) is participating in the event as a spectator. It seems to me that the same idea applies to community Linux conferences (such as LCA) and some Linux users group meetings. In terms of watching a lecture there are real benefits to downloading it after the conference so that you can pause it and study related web sites or repeat sections that you didn t understand. Also wherever you might sit at home to watch a video of a conference lecture you will be a lot more comfortable than a university lecture hall. Some people don t attend conferences and users group meetings because they would rather watch a video at home. Benefits of Attending (Apart from a Ritual) One of the benefits of attending a lecture is the ability to ask questions. But that seems to mostly apply to the high status people who ask most questions. I ve previously written about speaking stacks and my observations about who asks questions vs the number that can reasonably be asked [2]. I expect that most delegates ask no questions for the entire conference. I created a SurveyMonkey survey to discover how many questions people ask [3]. I count LCA as a 3 day conference because I am only counting the days where there are presentations that have been directly approved by the papers committee, approving a mini-conf (and thus delegating the ability to approve speeches) is different. Another benefit of attending is the so-called hallway track where people talk to random other people. But that seems to be of most benefit to people who have some combination of high status in the community and good social skills. In the past I ve attended the Professional Delegates Networking Session which is an event for speakers and people who pay the Professional registration fee. Sometimes at such events there has seemed to be a great divide between speakers (who mostly knew each other before the conference) and Professional Delegates which diminishes the value of the event to anyone who couldn t achieve similar benefits without it. How to Optimise a Conference as a Ritual To get involvement of people who have the ritualistic approach one could emphasise the issue of being part of the event. For example to get people to attend the morning keynote speeches (which are sometimes poorly attended due to partying the night before) one could emphasise that anyone who doesn t attend the keynote isn t really attending the conference. Conference shirts seem to be strongly correlated with the ritual aspect of conferences, the more corporate conferences don t seem to offer branded clothing to delegates. If an item of branded schwag was given out before each keynote then that would increase the attendance by everyone who follows the ritual aspect (as well as everyone who just likes free stuff). Note that I m not suggesting that organisers of LCA or other conferences go to the effort of giving everyone schwag before the morning keynote, that would be a lot of work. Just telling people that anyone who misses the keynote isn t really attending the conference would probably do. I ve always wondered why conference organisers want people to attend the keynotes and award prizes to random delegates who attend them. Is a keynote lecture a ritual that is incomplete if the attendance isn t good enough?

• [1] http://tinyurl.com/m74pc95
• [2] http://etbe.coker.com.au/2013/02/01/speaking-stacks/
• [3] https://www.surveymonkey.com/s/RZ958TJ

I recently had a medical appointment cancelled due to a computer crash . Apparently the reception computer crashed and lost all bookings for a day and they just made new bookings for whoever called and anyone who had a previous booking just missed out. I ll probably never know whether they really had a computer problem or just used computer problems as an excuse when they made a mistake. But even if it wasn t a real computer problem the fact that computers are so unreliable overall that computer crash is an acceptable excuse indicates a problem with the industry. The problem of unreliable computers is a cost to everyone, it s effectively a tax on all business and social interactions that involve computers. While I spent the extra money on a server with ECC RAM for my home file storage I have no control over the computers purchased by all the companies I deal with which are mostly the cheapest available computers. I also have no option to buy a laptop with ECC RAM because companies like Lenovo have decided not to manufacture them. It seems to me that the easiest way of increasing overall reliability of computers would be to use ECC RAM everywhere. In the early 90 s all IBM compatible PCs had parity RAM, that meant that for each byte there was one extra bit which would report 100% of single-bit errors and 50% of errors that involved random memory corruption. Then manufacturers decided to save a tiny amount of money on memory by using 8/9 the number of chips for desktop/laptop systems and probably make more money on selling servers with ECC RAM. If the government was to impose a 20% tax on computers that lack ECC RAM then manufacturers would immediately start using it everywhere and the end result would be no price increase overall as it s cheaper to design desktop systems and servers with the same motherboards apparently some desktop systems have motherboard support for ECC RAM but don t ship with suitable RAM or advertise the support for such RAM. This principle applies to many other products too. One obvious example is cars, a car manufacturer can sell cheap cars with few safety features and then when occupants of those cars and other road users are injured the government ends up paying for medical expenses and disability pensions. If there was a tax for every car that has a poor crash test rating and a tax for every car company that performs badly in real world use then it would give car companies some incentive to manufacture safer vehicles. Now there are situations where design considerations preclude such features. For example implementing ECC RAM in mobile phones might involve technical difficulties (particularly for 32bit phones) and making some trucks and farm equipment safer might be difficult. But when a company produces multiple similar products that differ significantly in quality such as PCs with and without ECC RAM or cars with and without air-bags there would be no difficulty in making them all of them higher quality. I don t think that we will have a government that implements such ideas any time soon, it seems that our government is more interested in giving money to corporations than taxing them. But one thing that could be done is to adopt a policy of only giving money to companies if they produce high quality products. If a car company is to be given hundreds of millions of dollars for not closing a factory then that factory should produce cars with all possible safety features. If a computer company is going to be given significant tax breaks for doing R&D then they should be developing products that won t crash.

More hardware adventures. I got my Dell XPS13. Amazing. The good news: This MacBook Air clone is clearly an Air competitor, and easily slightly better in nearly every regard except for the battery.
The bad news is that the Intel Wireless card needs non-free (I ll be replacing that shortly), and the touchpad s driver isn t totally implemented until Kernel 3.16. I m currently building a 3.14 kernel with the patch to send to the kind Debian kernel people. We ll see if that works. Ubuntu Trusty already has the patch, but it didn t get upstreamed. That kinda sucks. It also shipped with UEFI disabled, and was defaulting to boot in legacy mode. It shipped with Ubuntu, a bit disappointed to not see Ubuntu keys on the machine. Touchscreen works; in short -stunning. I think I found my new travel buddy. Debian unstable runs great, stable had some issues.

I recently got in contact with Nicolas Arenas Alonso and Nito Martinez from the Quindel group (located in Spain) [1]. Those guys bring forth a software product called TheQVD (The Quality Virtual Desktop) [2]. The project does similar things that X2Go does. In fact, they use NX 3.5 from NoMachine internally like we do in X2Go. Already a year ago, I noticed their activity on TheQVD and thought.. "Ahaaa!?!". Now, a couple of weeks back we received a patch for libxcomp3 that fixes an FTBFS (fails to build from source) for nx-libs-lite against Android [3]. read more

Following Enrico's terminal-emulators comparison, I wanted to implement "start a new terminal tab in my current working directory" for rxvt-unicode aka urxvt. As Enrico notes, this functionality is something between "rather fragile" and non-existing, so I went to implement it myself. Martin Pohlack had the right hint, so here's the patch:

--- /usr/lib/urxvt/perl/tabbed  2014-05-03 21:37:37.000000000 +0200
+++ ./tabbed    2014-07-09 18:50:26.000000000 +0200
@@ -97,6 +97,16 @@
       $term->resource (perl_ext_2 => $term->resource ("perl_ext_2") . ",-tabbed");
     ;
 
+   if (@  $self-> tabs   )  
+      # Get the working directory of the current tab and append a -cd to the command line
+      my $pid = $self-> cur pid ;
+      my $pwd = readlink "/proc/$pid/cwd";
+      #print "pid $pid pwd $pwd\n";
+      if ($pwd)  
+         push @argv, "-cd", $pwd;
+       
+    
+
    push @urxvt::TERM_EXT, urxvt::ext::tabbed::tab::;
 
    my $term = new urxvt::term
@@ -312,6 +322,12 @@
    1
  
 
+sub tab_child_start  
+   my ($self, $term, $pid) = @_;
+   $term-> pid  = $pid;
+   1;
+ 
+
 sub tab_start  
    my ($self, $tab) = @_;
 
@@ -402,7 +418,7 @@
 # simply proxies all interesting calls back to the tabbed class.
 
  
-   for my $hook (qw(start destroy key_press property_notify))  
+   for my $hook (qw(start destroy key_press property_notify child_start))  
       eval qq 
          sub on_$hook  
             my \$parent = \$_[0] term parent 

printer-driver-postscript-hp Depends: hplip
hplip Depends: policykit-1
policykit-1 Depends: libpam-systemd
libpam-systemd Depends: systemd (= 204-14)

Since the last in the above is a versioned dependency, that means you can't use systemd-shim to satisfy this dependency. I do think we should migrate to systemd. However, it's unfortunate that this change is being rushed like this. I want to migrate my personal laptop to systemd but not before I have the time to deal with any fallout that might result, and to make sure I can properly migrate my configuration. Workaround (for now): hold policykit-1 at 0.105-3 rather than have it upgrade to 0.105-6. That version doesn't have a dependency on libpam-systemd. Off-hand questions:

• Why does one need to log in to an init system? (yes, yes, it's probably a session PAM module, not an auth or password module. Still)
• What does policykit do that can't be solved with proper use of Unix domain sockets and plain old unix groups?

All this feels like another case of overengineering, like most of the *Kit thingies. Update: so the systemd package doesn't actually cause systemd to be run, there are other packages that do that, and systemd-shim can be installed. I misread things. Of course, the package name is somewhat confusing... but that's no excuse.

Once upon a time I setup a centralized service for spam-testing blog/forum-comments in real time, that service is BlogSpam.net. This was created because the Debian Administration site was getting hammered with bogus comments, as was my personal blog. Today the unfortunate thing happened, the virtual machine this service was running on ran out of RAM and died - The redis-store that holds all the state has now exceeded the paltry 512Mb allocated to the guest, so OOM killed it. So I'm at an impasse - I either recode it to use MySQL instead of Redis, or something similar to allow the backing store to exceed the RAM-size, or I shut the thing down. There seems to be virtually no liklihood somebody would sponsor a host to run the service, because people just don't pay for this kind of service. I've temporarily given the guest 1Gb of RAM, but that comes at a cost. I've had to shut down my "builder" host - which is used to build Debian packages via pbuilder. Offering an API, for free, which has become increasingly popular and yet equally gets almost zero feedback or "thanks" is a bit of a double-edged sword. Because it has so many users it provides a better service - but equally costs more to run in terms of time, effort, and attention. (And I just realized over the weekend that my Flattr account is full of money (~50 euro) that I can't withdraw - since I deleted my paypal account last year. Ooops.) Meh. Happy news? I'm avoiding the issue of free service indefinitely with the git-based DNS product which was covering costs and now is .. doing better. (20% off your first months bill with coupon "20PERCENT".)

I just made an account on yet another web service. On the suggestion of my password manager, I attempted to use the password W:9[$X*F . It was rejected because Password must contain at least one non-alphabet character, one lowercase letter, one uppercase letter . OK, how about Passw0rd ? Yep, that s fine. Anyone want to guess which of those two passwords is going to fall victim to a brute-force attack first? Go on, don t be shy, take a wild shot in the dark!

So I was at Ocracoke island, camping with family, and I brought my laptop along as I've done probably half a dozen times before. An enormous thuderstorm came up. It rained for 8 hours and thundered for 3 of those. Some lightning cracks quite close by as we crouched in the food tent, our feet up off the increasingly wet ground "just in case". The campground flooded. Luckily we were camped in the dunes and tents mostly avoided being flooded with 2-3 inches of water. (That was just the warmup; a hurricane hit a week after we left.) My laptop was in my tent when this started, and I got soaked to the skin just running over there and throwing it up on the thermarest to keep it out of any flooding and away from any drips. It seemed ok, so best not to try to move it to the car in that downpour. Next time I checked, it turned out the top vent of the tent was slightly open and dripping. The laptop bag was damp. But inside it seemed ok. Rain had slackened to just heavy, so I ran it down to the car. Laptop appeared barely damp, but it was hard to tell as I had quite forgotten what "dry" was. Turned it on for 10 seconds to check the time. It was 7:30 and we still had to cook dinner in this mess. Transferred it to a dry bag. (By the way, in some situations, discovering you have a single dry towel you didn't know you had is the best gift in the world!) Next morning, the laptop was dead. When powered on, the fan came on full, the screen stayed black, and after a few seconds it turned itself back off. I need this for work, so it was a crash priority to get it fixed or a replacement. Before I even got home, I had logged onto Lenovo's website to check warantee status and found 2 things:

1. They needed some number from a sticker on the bottom of my laptop. Which was no longer there.
2. The process required some stange login on an entirely different IBM website.

At this point, I had a premonition of how the beuracracy would go. Reading Sesse's Blehnovo, I see I was right. I didn't even try. I ordered a replacement with priority shipping. When I got home, I pulled the laptop apart to try to debug it. I still don't know what's wrong with it. The SSD may be damaged; it seems to cause anything I put it into to fail to work. New laptop arrived in 2 days. Since this model is now a year old, it was a few hundred dollars cheaper this time around. And now I have an extra power supply, and a replacment keyboard, and a replacement fan etc. And I've escaped the dead USB port and broken rocker switch of the old laptop too. The only weird thing is that, while my old laptop had no problem with my Toshiba passport USB drive, this new one refuses to recognize it unless I plug it into a USB 1.0 hub. Oh well..

---

Update: Ocracode for this trip: OBX1.1 P6 L7 SA3d+++b+c++ U2(rearended,laptop death) T4f2b1 R2T Bb+m++++n++
F+++u++ SC+s-g6 H+f0i3 V+++s++m0 E++r+

I put out the call for nominations for the 2014 Software in the Public Interest (SPI) Board election last week. At this point I haven't yet received any nominations, so I'm mentioning it here in the hope of a slightly wider audience. Possibly not the most helpful as I would hope readers who are interested in SPI are already reading spi-announce. There are 3 positions open this election and it would be good to see a bit more diversity in candidates this year. Nominations are open until the end of Tuesday July 13th. The primary hard and fast time commitment a board member needs to make is to attend the monthly IRC board meetings, which are conducted publicly via IRC (#spi on the OFTC network). These take place at 20:00 UTC on the second Thursday of every month. More details, including all past agendas and minutes, can be found at http://spi-inc.org/meetings/. Most of the rest of the board communication is carried out via various mailing lists. The ideal candidate will have an existing involvement in the Free and Open Source community, though this need not be with a project affiliated with SPI. Software in the Public Interest (SPI, http://www.spi-inc.org/) is a non-profit organization which was founded to help organizations develop and distribute open hardware and software. We see it as our role to handle things like holding domain names and/or trademarks, and processing donations for free and open source projects, allowing them to concentrate on actual development. Examples of projects that SPI helps includes Debian, LibreOffice, OFTC and PostgreSQL. A full list can be found at http://www.spi-inc.org/projects/.

It seems to be a great time for monitoring solutions. Some of you may have noticed that Icinga has released it's first stable version of the completely redeveloped Icinga 2. After several changes in the recent past, where the Team maintaining the Plugins used for several Monitoring solutions was busy moving everything to new infrastructure, they are now back on track. The recent development milestone is reached and a call for testing was also sent out. In the meanwhile I prepared the packaging for this bigger move. The packages are now moved to the source package monitoring-plugins, the whole packaging changes can be observed in the changelog. With this new release we have also some NEWS, which might be useful to check. Same counts for upstream NEWS. You can give the packages a go and grab them from my 'unstable' and 'wheezy-backports' repositories at http://ftp.cyconet.org/debian/. Right after the stable release, the packages will be uploaded into debian unstable, but might get delayed by the NEW queue due the new package names.

Back in March, I uploaded a Debian s version of lcdproc with a unique feature: user and maintainer configurations are merged during package upgrade: user customizations and developers enhancements are both preserved in the new configuration file. (See this blog for more details). This avoids tedious edition of the configuration LCDd.conf file after every upgrade of lcdproc package. At the beginning of June, a new version of lcdproc (0.5.7-1) was uploaded. This triggered another round of automatic upgrades on user s systems. According to the popcon rise of libconfig-model-lcdproc-perl, about 100 people have upgraded lcdproc on their system. Since automatic upgrade has an opt-out feature, one cannot say for sure that 100 people are actually using automatic upgrade, but I bet a fair portion are them are. So far, only one people has complained: a bug report was filed about the many dependencies brought by libconfig-model-lcdproc-perl. The next challenge for lcdproc configuration upgrade is brought by a bug reported on Ubuntu: the device file provided by imon kernel module is a moving target: The device file created by the kernel can be /dev/lcd0 or /dev/lcd1 or even /dev/lcd2. Static configuration files and moving target don t mix well. The obvious solution is to provide a udev rule so that a symbolic link is created from a fixed location (/dev/lcd-imon) to the moving target. Once the udev rule is installed, the user only has to update LCDd.conf file to use the symlink as imon device file and we re done. But, wait The whole point of automatic configuration upgrade is to spare the user this kind of trouble: the upgrade must be completely automatic. Moreover, the upgrade must work in all cases: whether udev is available (Linux) or not. If udev is not available, the value present in the configuration file must be preserved. To know whether udev is available, the upgrade tool (aka cme) will check whether the file provided by udev (/dev/lcd-imon) is present or not. This will be done by lcdproc postinst script (which is run automatically at the end of lcdproc upgrade). Which means that the new udev rule must also be
activated in the postinst script before the upgrade is done. In other words, the next version of lcdproc (0.5.7-2) will:

• Install a new udev rule to provide lcd-imon symbolic link
• Activate this rule in lcdproc postinst script before upgrading the configuration (note to udev experts: yes, the udev rule is activated with --action=change option)
• Upgrade the configuration by running cme migrate in lcdproc postinst script.

In the lcdproc configuration model installed by libconfig-model-lcdproc-perl, the imon device parameter is enhanced so that running cme check lcdproc or cme migrate lcdproc issues a warning if /dev/lcd-imon exists and if imon driver is not configured to use it. This way, the next installation of lcdproc will deliver a fix for imon and cme will fix user s configuration file without requiring user input. The last point is admittedly bad marketing as users will not be aware of the magic performed by Config::Model Oh well In the previous section, I ve briefly mentioned that imon_device parameter is enhanced in lcdproc configuration model. If you re not already bored, let s lift the hood and see what kind of enhancements was added. Let s peek in lcdproc configuration file, LCDd.conf file which is used to generate lcdproc configuration model. You may remember that the formal description of all LCDd.conf parameters and their properties is generated from LCDd.conf to provide lcdproc configuration model. The comments in LCDd.conf follow a convention so that most properties of the parameters can be extracted from the comments. In the example below, the comments show that NewFirmware is a boolean value expressed as yes or no, the latter being the default :

# Set the firmware version (New means >= 2.0) [default: no; legal: yes, no]
NewFirmware=no

Back to the moving target. In LCDd.conf, imon device file parameter is declared this way:

# Select the output device to use
Device=/dev/lcd0

This means that device is a string where the default value is /dev/lcd0. Which is wrong once the special udev rule provided with Debian packages is activated. With this rule, the default value must be /dev/lcd-imon. To fix this problem, a special comment is added in the Debian version of LCDd.conf to tune further the properties of the device parameter:

# select the device to use
#  %
#   default~
#   compute
#     use_eval=1
#     formula="my $l = '/dev/lcd-imon'; -e $l ? $l : '/dev/lcd0';"
#     allow_override=1 -
#   warn_if:not_lcd_imon
#     code="my $l = '/dev/lcd-imon';defined $_ and -e $l and $_ ne $l ;"
#     msg="imon device does not use /dev/lcd-imon link."
#     fix="$_ = undef;"
#   warn_unless:found_device_file
#     code="defined $_ ? -e : 1"
#     msg="missing imon device file"
#     fix="$_ = undef;"
#   - % 
Device=/dev/lcd0

This special comment between % and % follows the syntax of Config::Model::Loader. A small configuration model is declared there to enhance the model generated from LCDd.conf file. Here are the main parts:

• default~ suppress the default value of the device parameter declared in the original LCDd.conf (i.e. /dev/ldcd0 )
• compute and the 3 lines below computes a default value for the device file. Since use_eval is true, the formula is evaluated as Perl code. This code will return /dev/lcd-imon if this file is found. Otherwise, /dev/lcd0 is returned. Hence, either /dev/lcd-imon or /dev/lcd0 will be used a as default value. allow_override=1 lets the user override this computed value
• warn_if and the 3 lines below test the configured device file with the Perl instructions provided by the code parameter. There, the device value is available in the $_ variable. This code will return true if /dev/lcd-imon exists and if the configured device does not use it. This will trigger a warning that will show the specified message.
• Similarly warn_unless and the 3 lines below warns the user if the configured device file is not found.

In both warn_unless and warn_if parts, the fix code snippet is run when by the command cme fix lcdproc and is used to repair the warning condition. In this case, the fix consists in resetting the device configuration value so the computed value above can be used. cme fix lcdproc is triggered during package post install script installed by dh_cme_upgrade. Come to think of it, generating a configuration model from a configuration file can probably be applied to other projects: for instance, php.ini and kdmrc are also shipped with detailed comments. May be I should make a more generic model generator from the example used to generate lcdproc model Well, I will do it if people show interest. Not in the form yeah, that would be cool , but in the form, yes, I will use your work to generate a configuration model for project [...] . I ll let you fill the blank ;-)
Tagged: Config::Model, configuration, debian, lcdproc, Perl, upgrade

For my local backup regimen I use flexbackup to create a full backup twice a year and differential/incremental backups on a weekly/monthly basis. I then upload these to a new amazon S3 bucket for each half year (so each bucket corresponds to the a full backup plus the associated differentials and incrementals). I then set the bucket's lifecycle to archive to glacier (cheaper offline storage) from the month after that half year has ended (reducing costs) and to delete it a year after the half ends. It used to be possible to do this via the S3 web interface but the absolute date based options seem to have been removed in favour of time since last update, which is not what I want. However the UI will still display such lifecycles if they are configured and directs you to the REST API to set them up. I had a look around but couldn't any existing CLI tools to do this directly but I figured it must be possible with curl. A little bit of reading later I found that it was possible but it involved some faff calculating signatures etc. Luckily EricW has written Amazon S3 Authentication Tool for Curl (AKA s3curl) which automates the majority of that faff. The tool is "New BSD" licensed according to that page or Apache 2.0 license according to the included LICENSE file and code comments. Setup Following the included README setup ~/.s3curl containing your id and secret key (I called mine personal which I then use below). Getting the existing lifecycle Retrieving an existing lifecycle is pretty easy. For the bucket which I used for the first half of 2014:

$ s3curl --id=personal -- --silent http://$bucket.s3.amazonaws.com/?lifecycle   xmllint --format -
<?xml version="1.0" encoding="UTF-8"?>
<LifecycleConfiguration xmlns="http://s3.amazonaws.com/doc/2006-03-01/">
  <Rule>
    <ID>Archive and Expire</ID>
    <Prefix/>
    <Status>Enabled</Status>
    <Transition>
      <Date>2014-07-31T00:00:00.000Z</Date>
      <StorageClass>GLACIER</StorageClass>
    </Transition>
    <Expiration>
      <Date>2015-01-31T00:00:00.000Z</Date>
    </Expiration>
  </Rule>
</LifecycleConfiguration>

See GET Bucket Lifecycle for details of the XML. Setting a new lifecycle The desired configuration needs to be written to a file. For example to set the lifecycle for the bucket I'm going to use for the second half of 2014:

$ cat s3.lifecycle
<LifecycleConfiguration>
  <Rule>
    <ID>Archive and Expire</ID>
    <Prefix/>
    <Status>Enabled</Status>
    <Transition>
      <Date>2015-01-31T00:00:00.000Z</Date>
      <StorageClass>GLACIER</StorageClass>
    </Transition>
    <Expiration>
      <Date>2015-07-31T00:00:00.000Z</Date>
    </Expiration>
  </Rule>
</LifecycleConfiguration>
$ s3curl --id=personal --put s3.lifecycle --calculateContentMd5 -- http://$bucket.s3.amazonaws.com/?lifecycle

See PUT Bucket Lifecycle for details of the XML.

When I first started using computers a word processor was a program that edited text. The most common and affordable printers were dot-matrix and people who wanted good quality printing used daisy wheel printers. Text from a word processor was sent to a printer a letter at a time. The options for fancy printing were bold and italic (for dot-matrix), underlines, and the use of spaces to justify text. It really wasn t much good if you wanted to include pictures, graphs, or tables. But if you just wanted to write some text it worked really well. When you were editing text it was typical that the entire screen (25 rows of 80 columns) would be filled with the text you were writing. Some word processors used 2 or 3 lines at the top or bottom of the screen to display status information. Some time after that desktop publishing (DTP) programs became available. Initially most people had no interest in them because of the lack of suitable printers, the early LASER printers were very expensive and the graphics mode of dot matrix printers was slow to print and gave fairly low quality. Printing graphics on a cheap dot matrix printer using the thin continuous paper usually resulted in damaging the paper a bad result that wasn t worth the effort. When LASER and Inkjet printers started to become common word processing programs started getting many more features and basically took over from desktop publishing programs. This made them slower and more cumbersome to use. For example Star Office/OpenOffice/LibreOffice has distinguished itself by remaining equally slow as it transitioned from running on an OS/2 system with 16M of RAM in the early 90 s to a Linux system with 256M of RAM in the late 90 s to a Linux system with 1G of RAM in more recent times. It s nice that with the development of PCs that have AMD64 CPUs and 4G+ of RAM we have finally managed to increase PC power faster than LibreOffice can consume it. But it would be nicer if they could optimise for the common cases. LibreOffice isn t the only culprit, it seems that every word processor that has been in continual development for that period of time has had the same feature bloat. The DTP features that made word processing programs so much slower also required more menus to control them. So instead of just having text on the screen with maybe a couple of lines for status we have a menu bar at the top followed by a couple of lines of toolbars , then a line showing how much width of the screen is used for margins. At the bottom of the screen there s a search bar and a status bar. Screen Layout By definition the operation of a DTP program will be based around the size of the paper to be used. The default for this is A4 (or Letter in the US) in a portrait layout (higher than it is wide). The cheapest (and therefore most common) monitors in use are designed for displaying wide-screen 16:9 ratio movies. So we have images of A4 paper with a width:height ratio of 0.707:1 displayed on a wide-screen monitor with a 1.777:1 ratio. This means that only about 40% of the screen space would be used if you don t zoom in (but if you zoom in then you can t see many rows of text on the screen). One of the stupid ways this is used is by companies that send around word processing documents when plain text files would do, so everyone who reads the document uses a small portion of the screen space and a large portion of the email bandwidth. Note that this problem of wasted screen space isn t specific to DTP programs. When I use the Google Keep website [1] to edit notes on my PC they take up a small fraction of the screen space (about 1/3 screen width and 80% screen height) for no good reason. Keep displays about 70 characters per line and 36 lines per page. Really every program that allows editing moderate amounts of text should allow more than 80 characters per line if the screen is large enough and as many lines as fit on the screen. One way to alleviate the screen waste on DTP programs is to use a landscape layout for the paper. This is something that all modern printers support (AFAIK the only printers you can buy nowadays are LASER and ink-jet and it s just a big image that gets sent to the printer). I tried to do this with LibreOffice but couldn t figure out how. I m sure that someone will comment and tell me I m stupid for missing it, but I think that when someone with my experience of computers can t easily figure out how to perform what should be a simple task then it s unreasonably difficult for the vast majority of computer users who just want to print a document. When trying to work out how to use landscape layout in LibreOffice I discovered the Web Layout option in the View menu which allows all the screen space to be used for text (apart from the menu bar, tool bars, etc). That also means that there are no page breaks! That means I can use LibreOffice to just write text, take advantage of the spelling and grammar correcting features, and only have screen space wasted by the tool bars and menus etc. I never worked out how to get Google Docs to use a landscape document or a single webpage view. That s especially disappointing given that the proportion of documents that are printed from Google Docs is probably much lower than most word processing or DTP programs. What I Want What I d like to have is a word processing program that s suitable for writing draft blog posts and magazine articles. For blog posts most of the formatting is done by the blog software and for magazine articles the editorial policy demands plain text in most situations, so there s no possible benefit of DTP features. The ability to edit a document on an Android phone and on a Linux PC is a good feature. While the size of a phone screen limits what can be done it does allow jotting down ideas and correcting mistakes. I previously wrote about using Google Keep on a phone for lecture notes [2]. It seems that the practical ability of Keep to edit notes on a PC is about limited to the notes for a 45 minute lecture. So while Keep works well for that task it won t do well for anything bigger unless Google make some changes. Google Docs is quite good for editing medium size documents on a phone if you use the Android app. Given the limitations of the device size and input capabilities it works really well. But it s not much good for use on a PC. I ve seen a positive review of One Note from Microsoft [3]. But apart from the fact that it s from Microsoft (with all the issues that involves) there s the issue of requiring another account. Using an Android phone requires a Gmail account (in practice for almost all possible uses if not in theory) so there s no need to get an extra account for Google Keep or Docs. What would be ideal is an Android editor that could talk to a cloud service that I run (maybe using WebDAV) and which could use the same data as a Linux-X11 application. Any suggestions?

• [1] http://keep.google.com/
• [2] http://etbe.coker.com.au/2014/04/19/phone-based-lectures/
• [3] http://www.onenote.com/

After dealing with the client side of the DNSSEC puzzle last week, I thought it behooved me to also go about getting DNSSEC going on the domains I run DNS for. Like the resolver configuration, the server side work is straightforward enough once you know how, but boy howdy are there some landmines to be aware of. One thing that made my job a little less ordinary is that I use and love tinydns. It s an amazingly small and simple authoritative DNS server, strong in the Unix tradition of do one thing and do it well . Unfortunately, DNSSEC is anything but small and simple and so tinydns doesn t support DNSSEC out of the box. However, Peter Conrad has produced a patch for tinydns to do DNSSEC, and that does the trick very nicely. A brief aside about tinydns and DNSSEC, if I may Poor key security is probably the single biggest compromise vector for crypto. So you want to keep your keys secure. A great way to keep keys secure is to not put them on machines that run public-facing network services (like DNS servers). So, you want to keep your keys away from your public DNS servers. A really great way of doing that would be to have all of your DNS records somewhere out of the way, and when they change regenerate the zone file, re-sign it, and push it out to all your DNS servers. That happens to be exactly how tinydns works. I happen to think that tinydns fits very nicely into a DNSSEC-enabled world. Anyway, back to the story. Once I d patched the tinydns source and built updated packages, it was time to start DNSSEC-enabling zones. This breaks down into a few simple steps:

1. Generate a key for each zone. This will produce a private key (which, as the name suggests, you should keep to yourself), a public key in a DNSKEY DNS record, and a DS DNS record. More on those in a minute. One thing to be wary of, if you re like me and don t want or need separate Key Signing and Zone Signing keys. You must generate a Key Signing key this is a key with a flags value of 257. Doing this wrong will result in all sorts of odd-ball problems. I wanted to just sign zones, so I generated a Zone Signing key, which has a flags value of 256. Big mistake. Also, the DS record is a hash of everything in the DNSKEY record, so don t just think you can change the 256 to a 257 and everything will still work. It won t.
2. Add the key records to the zone data. For tinydns, this is just a matter of copying the zone records from the generated key into the zone file itself, and adding an extra pseudo record (it s all covered in the tinydnssec howto).
3. Publish the zone data. Reload your BIND config, run tinydns-sign and tinydns-data then rsync, or do whatever it is PowerDNS people do (kick the database until replication starts working again?).
4. Test everything. I found the Verisign Labs DNSSEC Debugger to be very helpful. You want ticks everywhere except for where it s looking for DS records for your zone in the higher-level zone. If there are any other freak-outs, you ll want to fix those because broken DNSSEC will take your domain off the Internet in no time.
5. Tell the world about your DNSSEC keys. This is simply a matter of giving your DS record to your domain registrar, for them to add it to the zone data for your domain s parent. Wherever you d normally go to edit the nameservers or contact details for your domain, you probably want to do to the same place and look for something about DS or Domain Signer records. Copy and paste the details from the DS record in your zone into there, submit, and wait a minute or two for the records to get published.
6. Test again. Before you pat yourself on the back, make sure you ve got a full board of green ticks in the DNSSEC Debugger. if anything s wrong, you want to rollback immediately, because broken DNSSEC means that anyone using a DNSSEC-enabled resolver just lost the ability to see your domain.

That s it! There s a lot of complicated crypto going on behind the scenes, and DNSSEC seems to revel in the number of acronyms and concepts that it introduces, but the actual execution of DNSSEC-enabling your domains is quite straightforward.

Since the release of xf86-video-intel 2.99.912 a month ago several enhancements and fixes in xf86-video-intel git piled up. Again testing is very much appreciated: xserver-xorg-video-intel packages.

In short: I love my MacBook Air. It is the best (laptop) hardware I ever owned. I have seen hardware which was much more flaky in the past. I can set the display backlight to zero via software, which saves me a lot of battery life and also offers a bit of anti-spy-acroos-my-shoulder support. WLAN and bluetooth work nicely. And I just love the form-factor and the touch-feeling of the hardware. I even had the bag I use to carry my braille display modified so that the Air just fits in. I can't say how it behaves with X11. Given how flaky accessibility with graphical desktops on Linux is, I have still not made the switch. My MacBookAir is my perfect mobile terminal, I LOVE it. I am sort of surprised about the recent rant of Paul about MacBook Hardware. It is rather funny that we perceive the same technology so radically different. And after reading the second part of his rant I am wondering if I am no longer allowed to consider myself part of the "hardcore F/OSS world", because I don't consider Apple as evil as apparently most others. Why? Well, first of all, I actually like the hardware. Secondly, you have to show me a vendor first that builds usable accessibility into their products, and I mean all their products, without any extra price-tag attached. Once the others start to consider people with disabilities, we can talk about apple-bashing again. But until then, sorry, you don't see the picture as I do. Apple was the first big company on the market to take accessibility seriously. And they are still unbeaten, at least when it comes to bells and whistles included. I can unbox and configure any Apple product sold currently completely without assisstance. With some products, you just need to know a signle keypress (tripple-press the home button for touch devices and Cmd+F5 for Mac OS/X), and with others, during initial bootup, a speech synthesizer even tells you how to enable accessibility in case you need it. And after that is enabled, I can perform the setup of the device completely on my own. I don't need help from anyone else. And after the setup is complete, I can use 95% of the functionality provided by the operating system. And I am blind, part of a very small margin group so to speak. In Debian circles, I have even heard the sentiment that we supposedly have to accept that small margin groups are ignored sometimes. Well, as long as we think that way, as long as we strictly think economically, we will never be able to go there, fully. And we will never be the universal operating system, actually. Sorry to say that, but I think there is some truth to it. So, who is evil? Scratch your own itch doesn't always work to cover everything. How do we motivate contributors to work on things they don't personally need (yet)? How can we ensure that complicated but seldomly used features stay stable and do not fall to dust just because some upstream decides to rewrite an essential subcomponent of the dependency tree? I don't know. All I know is that these issues need to be solved in an universal operating system.