Category Archives: Meta

Blog posts about the blog and web page. See it as a sort of “meta-blog”

Fields of Gold

I’ve been quite busy studying, and am thus lagging behind in my postings. I have so much to share, but I will do as usual and just publish a few photos at a time. Stay tuned.

Fields of Gold

The Fields of Gold. Tried some new tricks with this one. There are more things in this world than sharpness and acuity ;)

Suhosin woes

I have been struggling with the webserver recently, and I just got it to work well again. The outages you might have noticed the last few days are now fixed.

Technical stuff follows.

For future reference, and to help fellow googlers I thought I’d post the solution here. Apache started segfaulting on the wordpress administration pages after upgrading to wordpress 3. For some reason, all admin pages were truncated, removing javascript and casing very curious behavior.  Digging further, I found that apache threw segmentation faults whenever I browsed these pages. After taking a backtrace with debugging symbols on the httpd process (I am using apache 1.3.29, openbsd 4.5) I was able to deduce that the problem was in the php suhosin patches applied by the openbsd packagers. Recompiling apache via the ports system without suhosin made the problem go away. It just took a dozen hours to find this stupid problem.

Credit goest to the friendly people in the #php channel on freenode for helping me out.

Minor update

I’ve added two links to my blogroll.

First, another Yi student from Linköping who will be at the ETH next year, Andreas. (Swedish page)

Then a friend from ICF (church) here in Zürich who is in Shanghai this semester, Mathias. (German page)

Now it’s time for the Fluid Dynamics lecture. Have fun!

There, I fixed it.

The exam period is an interesting time. You do a lot of studying, and end up being productive in all aspects of your life. Anything to get away from the studying books. Never has the room been so neat and tidy, and never have you got so much done in so little time. The last week I finally grew so tired of the old (ugly) design of this page that I figured it was time to do some overhaul. Now I’ve re-branded the page to be more themed on Switzerland, with the Engadin alps decorating the banner. This blog is gradually becoming more and more a photography blog, so I’ve made several improvements in that respect as well.

Oh yes, time to go back to the lecture notes, I’ve got to learn those polynomial ring theorems.

Far East

My sister Susanna and her friend Emma just went to Zhenjiang, China for a four-week trip. She’s doing the same type of International Workplace Training that I did four years ago in Bangalore, India as a part of the studies at ABB Industrial Highschool in Västerås.

Susanna’s got her own blog (in Swedish).

Stupid webbrowsers

Apparently this web page has been completelz unviewable in Internet Explorer for some time now. I can only apologize to anybody who has been browsing this webpage and seeing only the top navigation links. Since I use Linux, there is no easy way for me to test the design in Internet Explorer when doing changes to the layout.

Now, the bug was triggered by an extremely difficult-to-hit bug, the “IE7 disappearing content bug“. As soon as I found the problem, the solution was simple. I just had to add

min-width: 0;

to the css declaration of the disappearing content element. Really, really stupid bug that only the god-forsaken, bug-ridden menace of Internet Explorer has.

Now, if there are any more issues that I might have missed, contact me as soon as possible.

Adapt, adopt, improve!

I have to apologize to everybody who’s been unable to visit my blog the past week or so. There’s been some downtime, but I hope that the issues are sorted out by now. Here’s the story behind the outages.

The whole summer I’ve been planning a major overhaul of the servers I’m running in the cellar, and this last week I’ve been working hard on effecting these changes. Shutting down a server that has been running continuously for 480 days is never easy, but there was no option because of the extremely serious sock_sendpage vulnerability recently found in the Linux kernel. The updates I’ve done have been the focused around security, and since I’ll be abroad for the next year everything needs to work with minimal need for maintenance.

The new setup is a combination of one server running the very secure operating system OpenBSD spiced with additional measures such as chrooting and intrusion detection, and one server with six virtual computers running Ubuntu through Xen. All machines are protected with an advanced intrusion detection system and a separated logging server, hopefully making any intrusion attempts detectable and void. But no-one can achieve perfect security, and I won’t say I’m immune to attacks though I hope I’ve made the systems robust enough. In the process I have learned a new operating system, OpenBSD, and I’ve almost fallen in love with it :) I must be a strange person.

Now everybody back home knows enough to keep the servers running when I’m away, and I’ve specifically asked them to make sure things stay afloat in the event of a power failure. The battery backups are cheap and not very reliable, but they protect against the minor outages and prevent the most annoying sub-second power spikes.

Enough of this technical mumbo-jumbo, here follows a picture of these new computers that will be working hard to serve you these web pages! (Nothing would work without that typewriter.)

Servers, August 2009

The world of Yi

world_of_yi

I and my university class of twelve have now completed two years of studies at Linköping University and the exciting third year now begins. Everybody in the class are studying applied physics with international perspective, and we are all going abroad for the third year, studying physics in our respective languages.  My profile language is German, but in the class there are students of Mandarin, Japanese, Spanish and French as well.

Jesper has done a great job setting up a homepage for our adventure and all of us are going to have a blog of some sort where write about the life in the foreign country.

I have added my blogging classmates to the links on the sidebar, you can also click the links below to read their blogs:

Mandarin

  • Daniel, National Tsinghua University, Hsinchu City, Taiwan
  • Christopher, National Central University, Jhongli City, Taiwan
  • Per, Nanjing University, Nanjing, China

Japanese

  • Pär, University of Tokyo, Tokyo, Japan
  • Carl, Saitama University, Toky, Japan
  • Jakob, Chiba University, Chiba, Japan

French

  • Lovisa, Institut Polytechnique de Grenoble, Grenoble, France
  • Jesper, Polytech Montpellier, Montpellier, France
  • Li, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
  • Viktor, Ecole Nationale Supérieure des Mines de Nancy, Nancy, France

Spanish

  • Frida, Universidad Técnica Santa Maria, Valparaiso, Chile

German

  • Myself, Jonathan. Eidgenössische Techische Hochschule (ETH), Zürich, Switzerland

For my own part, I now only have 18 days until my flight departs for Zürich but I haven’t yet grasped that I finally am going abroad. Many things must be prepared, I’ll someway have to wedge in a year’s worth of packing into the 20 kg luggage weight restriction.

My university class
Above: Class of Yi3 (minus Daniel and Lovisa)

Trilinguality

I have now decided to start blogging in more languages than English. Partially because just blogging in English often becomes a holdback and making me blog less often.

From today you’ll also receive blog posts in Swedish, and in the future I hope to add German as well.

For all you English-speaking folks (according to statistics, you do account for more than 90% of my blog visitors) I provide you with this page, an excellent resource for learning Swedish. And if you wonder why everyone else is laughing: Don’t worry about it.

Aggregation

Hello, Planet Lysator!