teh bigbro blog(tm)

HEAnet are hiring

Fri, 27 Apr 2012 02:18:00 GMT

An ex-employer of mine, HEAnet Ltd. are hiring, looking for a Technical Project Manager. I enjoyed every minute of working with HEAnet and wouldn't hesitate to recommend there as a great place to work. Get applying! Full application details are in the job specification.

I'm travelling light...

Tue, 27 Mar 2012 22:30:00 GMT

...but yet have five (5) internet enabled devices. I love living in the future. I do wish hotel internet understood the future too.
( 2 x mobile phones, 1 x iPod, 1 x Kindle and a laptop.)

Apple - why do you hate me? Why?

Mon, 20 Feb 2012 00:48:00 GMT

In order to use netflix now that it's come to Ireland, I had to update my Apple TV. It failed, resulting in a perpetually flashing white light on the front and an apple logo displayed on the connected monitor.

Apparently this is (almost) normal. This support thread would seem to suggest that this is a fairly regular occurrence. The same failure is reported here.

In fact, it appears this failure is so common, someone has taken the trouble to write a comprehensive recovery howto, which I'm just about to try now.

If that doesn't work it's back to Apple it goes. Next time, please TEST your update software before releasing it. I buy Apple products to save my time, not to waste more of it.

Ubuntu 10.10

Sun, 08 Jan 2012 17:07:00 GMT

I powered up an old laptop today, revealing the simple and beautiful usability that was Ubuntu 10.10. It was not a perfect release - having some issues with Intel graphics drivers and continuing a kernel bug that prevented my trusty Dell D430 from sleeping and waking without kernel panic'ing - but it was largely a usable and stable release.

Post Unity, I've moved on to Fedora and Debian with my other half testing a Debian + KDE build for her laptop to see what she thinks. I cannot find the time to unbreak all the things that the latest revisions of Ubuntu have broken, nor do I have the time to suddenly learn a whole new desktop paradigm when the old one seemed to work quite well. I'm sure the fault lies with me, though I was interested to see an Irish Times article suggesting that similar paradigm shifts in OS X was encouraging the reporter to move away from OS X (and towards Linux.)

While I am, and have been, absolutely encouraging of making Linux suitable for novice users, allowing them a stable operating platform to support their migration from Windows, or perhaps first foray into technology, it is my opinion that Linux desktop developers should remember that they now have a significant body of users / power-users who are already using Gnome and KDE on a daily basis. This means that any proposed changes must be weighed against the impact caused to existing installations. The Linux desktop is no longer a green-field site. There are improvements to be made, undoubtedly, but please be mindful of forcing a paradigm shift onto existing satisfied users who are only upgrading to get the latest versions of software. Perhaps consider offering two upgrade paths - one for users who wish to just get the latest version of kernels, office suites and the like, and a second who are willing or indeed actively seeking a whole new desktop interface. Specifically, do not provide a large tempting 'Upgrade' button without due warning that this will utterly change the look and feel of the desktop.

Ubuntu was a great, usable operating system which I could not only rely on myself, but also install on machines operated by (extended) family members for which I am the support provider. I encourage them to update their machines regularly since I could trust that nothing too bad would happen. I had not counted on Unity, which "broke" their user experience - and my trust in Ubuntu as a platform provider. (Their words were that it broke their computer.)

While my example has referred to Ubuntu, my point stands for any operating system distribution - not even limited to Linux based distros. While technology markes forward, it's important to provide existing users with a sane method of receiving updates, without pushing them unnecessarily into having to re-learn their workflow. Microsoft Office 2007 seems to have been the interface change that broke the camel's back for Microsoft's Office suite - let's make sure that Unity does have the same negative impact on Linux as a desktop platform.

S**ty Smoke Alarms

Fri, 09 Dec 2011 03:21:00 GMT

I'm pretty sure my house is not on fire, and through repeated alarm soundings I hope I have isolated the fault to the smoke detector upstairs. I've checked pretty thoroughly and cannot find any sign of fire - nor with a real fire event would I expect such a protracted silent period after reactivation of the detector before it sounds again. The upstairs smoke detector has been removed from the ceiling and had its battery removed - the two downstairs ones are back in service. I'm now waiting to see if there's another alarm event.

On the plus side, I'm happy that should a smoke / fire event occur I will be awoken by three really loud alarms throughout the house - this is good.

On the minus side, I'm fairly annoyed that engineering shortcuts and/or assumptions make it really difficult to track down what's going on in a system such as this, and consequently to trust it in the future. I have three interlinked smoke / heat alarms - so if any one detects a fire they ALL go off - great to wake the people upstairs in the case of a fire downstairs. Unfortunately, this means that it's impossible to tell WHICH ONE triggered the event. Tonight, since I was unlucky enough to start with the kitchen one while fault finding, we've had 4 protracted loud alarms. The small girls, who were eventually awoken, are not going to be in a good mood tomorrow morning.

Lack of a 'silence alarm' button meant that there is no way for me to silence the alarm except to rip the things bodily of their ceiling mounts and remove their batteries too. While I appreciate that this feature might be abused, it somewhat assumes 100% accuracy (or that the safety of continuing to sound outweighs the need for adding a silence feature - something I can see the merit of, until you have to deal with a chain of smaoke alarms that are making 110dB alarm sounds repeatedly at 2:30am - with no sign of fire or danger.) Switches cost money to add and bring their own set of failure modes though, so I'm wlling to overlook this.

Unforgivably though, it appears noone thought to provide any indication as to which unit detected a heat / smoke event, and which ones are merely acting as alarm sounders on the say-so of that other unit. LEDs are not expensive to add and would have provided me not only with a quicker target for fault-finding, but also immediately concentrated the search area for a fire / smoke event. Instead, I had to search the entire house, upstairs and down, not knowing which detector had detected something.

Moral of the story: if you can't prove something will work 100% of the time, you'd better provide a method of monitoring and debugging it. If you can prove it will work 100% of the time, your proof is probably flawed, so you'd better provide a method of monitoring and debugging it.

Smoke Alarms

Fri, 09 Dec 2011 02:57:00 GMT

It's 2:48am and I've removed the second of three smoke alarms from the circuit to try and figure out which one is spuriously setting them all off. For the sake of the extra 10c, could manufacturers put an extra red LED in the package to indicate which one is alarming (and conversely which ones are merely sounding due to receiving an alarm signal from the chain.)

Also, why do really loud things seem to break at night / while it's quiet?

Diagnosing Smoke alarm system failure

Fri, 09 Dec 2011 01:48:00 GMT

Turns out that having a set of smoke alarms that are interlinked is a great idea - to make sure the alarm from one sounds throughout the house. It's a lot less useful when one alarm fails though: resulting in the alarm sounding throughout the house but without any indication of where the fault might be.
In a slightly worrying discovery, the girls remained sound asleep through some ten minutes of 3 x 110dB alarms sounding, even though I opened bedroom doors to check on them.
Anyone know where I can get a set of interlinked smoke-alarms, with an individual alarm indicator on them so I know which one set off the chain, that sound even louder?

'Hand' Cooked Crisps

Sun, 06 Nov 2011 12:28:00 GMT

I'm enjoying some Pret A Manger crisps, somewhat amused by the claim on the packet that they were 'Cooked by Hand.' I strongly suspect they used some form of chemical or electrical heating appliance, given I can't really see how you'd make human hands much hotter than 37 deg C (without outside intervention.)
Perhaps they have a huge frier shaped like a hand...

ILUG AGM 2011

Sat, 05 Nov 2011 17:26:00 GMT

The Irish Linux User Group held its annual general meeting today in the Irish Computer Society building in Dublin.
Thanks to the speakers who gave generously of their time to speak on the following topics (slidesets shall be made available here later, as soon as I get them :) )

Linux Professional Institute - Medina Dupois & Bill Quinn (LPI)
The LPI set of standard exams has grown with the prevalence of the Linux operation system, with companies looking for a coherent, respected accreditation of potential employees. Development continues with a new entry level exam to help graduates and even students to gain some accreditation of their Linux abilities without having to achieve the level required by the LPIC 1 certification.

Some Fragments of Haskell - Glenn Strong (TCD)
A whirlwind tour through some functional programming concepts and the reasoning behind Haskell. Slides will explain this a lot better than I ever could :-)

The Time Lords / The History of Time / Time and Place - Kevin Lyda (Google)
It's probably reasonable to assume that most people (with a watch) know what time it is, but things start to get complex when things like timezones, daylight savings time, leap-seconds, and applications that require accurate times over a large (tens/hundreds of years) period are brought into play. The tzdata database which tells your Linux system what the local time and date is - automatically changing for daylight savings at the right time - has been maintained for some 25 years, and is still being maintained and updated to this day.

To honour the 20 years of Linux, Frank, our venerable chair, ran a couple of early versions of Linux, including a version Linus Torvalds released early in the OS's lifetime - a new committee was elected - and we had cake!

Things I have eaten today...

Thu, 08 Sep 2011 20:37:00 GMT

1. Toast
*sigh* - I hate being ill :-(

Compiz crash / segfault on Fedora Linux

Wed, 31 Aug 2011 18:15:00 GMT

I am seeing a repeatable segfault in compiz on my Dell D430, running Fedora Linux (F14) - when I plug an external monitor or projector into the VGA socket. Booting the computer with the external VGA device plugged in works pretty much as expected, including giving me the ability to set up mirroring of screens or extending my desktop on to the second monitor.
Just starting to look into this to see if I can find out how to resolve - any pointers or hints would be appreciated (to blog-at-signal2noise.ie as per usual.)


[89877.883859] [drm:output_poll_execute] *ERROR* delayed enqueue failed -125
[89878.140938] stereo mode not supported  ((repeated 3 times))
...
[89881.479976] compiz[2276]: segfault at 0 ip 00e26026 sp bfb207b0 error 4 in i915_dri.so[dfc000+2ce000]
[89883.060177] stereo mode not supported  ((repeated many times until I restarted X))
...

[root@lynx ~]# uname -a
Linux lynx.signal2noise.ie 2.6.35.14-95.fc14.i686.PAE #1 SMP Tue Aug 16 21:12:22 UTC 2011 i686 i686 i386 GNU/Linux

Google Technology User Group (GTUG) Meeting, Dublin

Wed, 27 Jul 2011 09:18:00 GMT

Yesterday evening saw a very interesting talk about the Google Storage API - including a method of using the same tool - gsutil - to copy data on and off the Amazon S3 cloud. Following that was the Google Prediction API and two live demos: the first determining the probable language of an input string (having taught the system what French, Spanish and English looked like first) and the second estimating the potential price of a house based on some parameters and a list of selling prices for houses in a region. Powerful stuff indeed!

The second half was an interesting discussion of whether the Hackerspace ethic can or even should be integrated with an established traditional education system. Contributors ranged from the Leaving Cert student who first installed Linux at age 6, to the lecturer working on his third PhD. I'm not convinced any conclusion was reached - but perhaps it's more about the journey and discussion.

All in all, a most interesting evening, topped off with insightful conversation in the Schoolhouse after the event. I'm looking forward to the next one, provisionally set for the 23rd August.

Recordings of the event were made and are initially available from http://www.ustream.tv/recorded/16257161.

Twitter for conferences

Tue, 05 Jul 2011 09:30:00 GMT

So you're going to use Twitter at your conference or event. Here are some of the things I learned might be good ideas, shared for your enjoyment. I imagine as we do more events with Twitter and other social networking infrastructures, I'll update this post with new ideas.

Before the event

Prepare well in advance to get the most out of Twitter
Make sure you have a twitter user account and know how to use it
Define who will post before and during the event
Test!
Add info on twitter to the call for papers, any advertising for the event, the website and program - making sure to include the username(s) and/or hashtag(s) people should follow. Typical usage might be a username (like @companyX) for all information from the entity and a hashtag (#myevent2011) for a specific event.
Remember that Social Media is bi-directional. Encourage feedback from the attendees. Even before the event!

At / During the event

Consider putting up a couple of big screens in the event venue that will show tweets from and to your @username and following any #hashtags for the event.
Inform all the organisers know who can post to the twitter account and make sure they convey information on timetable changes, last-minute updates and whatnot to whoever can post. It's okay to have multiple people posting of course.
If conference organisers are going to be posting from mobile devices, test before the conference.
Remember that by showing hashtags on big screens in the venue, people who tweet with that hashtag can see their feedback on the big screen. That's an immediate feedback loop for those willing to contribute - and a great way for any attendee to communicate with the entire event audience. Communication is good - encourage it.

After the conference

Be sure to announce the next conference, thank people for contributing and consider announcing if any actions will result from the client feedback. This gives you the opportunity to show those who made the effort to post messages that you care and will do something useful with the feedback received.
Keep tweeting. It's an excellent opportunity to continue communicating with those people who subscribed to your feed for the event.
Gather and analyse the feedback you got from people, good and bad. Do something about it. Tweet that you're doing something about it. If you reward feedback received - both good and bad - then people will be more inclined to give you feedback in the future, and feedback helps you learn what your customer wants.

Fedora 14 on a Dell D430

Mon, 30 May 2011 18:32:00 GMT

It's been one week since I migrated my trusty Dell D430 laptop to Fedora 14 from Ubuntu 10.04 - the main requirement being that things like Suspend/Resume worked. Ubuntu broke this functionality on the D430 some releases ago - about 9.04 or so - and have yet to fix it (I've not tested Ubuntu 11.04 yet!) Note that Ubuntu works flawlessly on a D420, the predecessor, so it could be a BIOS feature rather than the fault of Ubuntu per se.
Ubuntu, upon initiating a hibernate (to disk), would at least have the grace to hang the kernel, but come back after a cold reboot. Fedora appears to have done something different, resulting in the machine becoming unbootable after it hibernates, dropping instead to the grub rescue> prompt. Note that this might have something to do with my swap partition being encrypted - something I'll test at a later date.
So - for the next time I need to do it, here's how to disable Hibernate on a Fedora laptop (at least for Fedora 14):

Edit, as root, /usr/share/polkit-1/actions/org.freedesktop.upower.policy This configures both suspend and hibernate options and allows them to be enabled or disabled.

Find the section starting

Within the above section, find the section, and within that section the yes part.

Change the yes to a no, to disable hibernate. The equivalent section exists for suspend if you want to disable that too.

Reboot - you're done and your system should no longer attempt to hibernate.

If, like me, you discover that your system has already hibernated and made itself unbootable, try the following (at your own risk! You did make a complete backup of your system, right?!?)

Boot your system from a Linux system on a USB stick or CD. I used a USB stick with Ubuntu 11.04 created with unetbootin.

Mount at least your root and boot partitions, using cryptsetup under a target directory. I used mkdir /mnt/target && cryptsetup luksOpen /dev/sda2 root && mount /dev/mapper/root /mnt/target && mount /dev/sda1 /mnt/target/boot

Mount the required system directories : mount --bind /dev /target/dev && mount --bind /proc /mnt/target/proc && mount --bind /dev/pts /mnt/target/dev/pts && mount --bind /sys /mnt/target/sys

chroot to your target system, which should map to the disk layout your laptop would have if it had booted normally : chroot /mnt/target

Run grub-install to make grub behave itself : grub-install /dev/sda

sync and unmount everything, then reboot and see if things worked.

Thanks to headkase for info on disabling hibernate functionality.

TNC2011 : Tiring but worthwhile

Wed, 18 May 2011 16:29:00 GMT
This TERENA Conference has seen many diverse topics covered: the future of networking, the packet v circuit debate, privacy implications in a modern connected world and the future of NRENs themselves. On top of this there's the constant interactions with other attendees - attendees with whom I collaborate with during the year via video-conference, e-mail, IM, Skype and numerous other ways. This conference is one of the few opportunities to sit down in person and discuss progress on projects, where things are going in the future, and ideas too immature or risque to be committed to e-mail yet.

As a result, it's Day 3 of the conference (day 5 in Prague for me) and I'm exhausted. Exhausted but exceptionally impressed at the quality of the presentations, the insight delivered by the speakers and those posing questions and the sheer dedication of the attendees who are tireless in their efforts to improve research and education networking.

TNC2011 : Why are computers and networks important?

Tue, 17 May 2011 10:56:00 GMT
Why do we build ever larger and more complex networks? Is it because computers are cool? Do we just need more bandwidth to view ever more amusing videos on Youtube, ever more grammatically inaccurate lolcats or socialise more without leaving the house through Facebook? Fundamentally, do we run the risk of perpetuating the network purely for the purpose of perpetuating the network?

Jaroslav Koča disagrees. His work relates to analysis of viruses, with a view to developing medicines to prevent viral infections, or prevent them from spreading. To this end he demonstrated how his team's software, with access to large networks and supercomputing resources can test which molecular bonds viruses might make with human cells, and find alternate molecular structures that will bond better. This provides a key building block to developing medicines that prevent viral infection, or at least control them.

He was able to show that hundreds of thousands of alternative compounds and structures, and variations of them, can be tested against a viral signature, allowing what would have taken months, if not years, of research by trial and error to be achieved in three days computing time. International high-capacity research networks providing links between supercompute and storage resources allow Jaroslav and his team to collaborate with teams in other universities and countries and share compute time to achieve quicker and more accurate results.

I'm proud to be part of an NREN delivering services that might some day literally find a cure for the common cold.

Jaroslav's plenary presentation at TNC2011 provided an excellent example of what big networks, big computing, big storage and tight collaboration between educational and research institutions can achieve - and served to remind me why I do my job with HEAnet.

The presentation slides for Jaroslav's talk are available here and the video is here.

TNC2011 : Sending arbitrary sized files simply and confidently

Mon, 16 May 2011 17:58:00 GMT
Did you know that the FileSender project allows you to send arbitrary sized files to one or more recipients simply and confidently? Information on development is on the filesender website and filesender blog and it's freely downloadable under the BSD license if youy want to set up your own repository.

The concept is simple - a user logs in and uploads a file, providing one or more e-mail addresses to send the file to. The recipient(s) get a mail providing a website URL from which they can download the file. Federated authentication is supported, as is the concept of invitations such that people without accounts can be requested to send you files.

HEAnet, the Irish NREN (National Education and Research Network) runs the service at filesender.heanet.ie and is available to anyone in the Edugate federation.

TNC2011 : TERENA TAC Meeting

Mon, 16 May 2011 11:45:00 GMT
While the TAC (Technical Advisory Council) meeting is a closed meeting, I can say that this year, more than any previous, a huge spread of material was covered. Good discussions on matters related to next generation network design, mobile connectivity, social networking and strategy for cloud computing were all discussed, with excellent feedback and insightful questions from many of the representatives.
Overall, a hugely informative meeting, though one that posed at least as many questions as it answered. Certainly enough material there to keep me busy for the coming year, and I think that goes for the other representatives and NRENs here too.

(edit: Corrected the title to 'TERENA TAC' - apologies for my brain-fart.)

TERENA Networking Conference - Day -1

Sun, 15 May 2011 13:23:00 GMT
It's still a day before the TERENA networking conference, but groups of people are meeting throughout the conference venue to discuss various technical issues and progress the state of Educational and Research Networking throughout Europe.
The Clarion Congress Hotel seems good and the TERENA technical crew here already have eduroam wireless networking in place.
You can follow the events of the conference by following #tnc2011 on twitter (and probably some other tags as well.)

Caladh Nua

Thu, 03 Mar 2011 08:34:00 GMT
Every now and again I 'rediscover' music - be it old music that I've not listened to for an extended period and uncover once more, or new music that reminds me just how much I truly enjoy and live for music. Random shuffle through my trusty iPhone this morning uncovered Happy Days by Caladh Nua, an album Rach got me for Christmas. Thanks to Niall for introducing me to Eoin and of course to Rach for buying me the CD.
Sometimes it's in coming back to music that makes you appreciate it all the more - and Happy Days stands the test of time. Good luck to the Lads (and Lisa) with their next album, Next Stop, which I have yet to get my hands on - but soon will :-)