Category Archives: geek

Worldwide network measurements with RIPE Atlas

Posted by on October 16, 2011 No comments

The RIPE NCC is the Regional Internet Registry (RIR) for Europe, the Middle East and parts of Central Asia. It’s an administrative and technical organization in charge of allocation and registration of Internet number resources (AS numbers and IP adresses) in its region.

In december 2010 they started a new experimental project named RIPE Atlas. The aim of this project is to “produce a collection of live Internet maps with unprecedented detail” by distributing small probes across the region to collect details about the network from thousands of different locations. Anyone can participate, you can request your probe for free but notice that least equipped areas will get their probe first!

Few days ago I received mine, the hardware is an XPort® Pro from Lantronix customized by the RIPE with the MAC address of the device printed on a side.

The device contains a tiny 32-bit Freescale processor with 16MB of Flash, a 100Base-TX RJ45 connector and a USB port to give its power to the device.

The probe connected to my home router (Freebox)

Currently the predefined measurements are made against the first and second hops, a bunch of root servers and some RIPE subdomains. It is expected (with the next firmware update) that anyone with an up & running probe will earn points that could be converted at anytime to execute his own measurements within the Atlas network. It’s worth noting that the probe supports IPv4 and IPv6 as well.

The members’ area of the website is rather well-made but requires a lot of Javascript to work. For example they have made their own tabs for navigating between links. IMHO this is overkill but it’s definitely usable.

Once logged in you can access the graph generated by your own probe but also probes from others, this is not very useful at this time but it’s definitely great to see how others perform from different regions of the globe!

The Atlas network was designed with openness in mind thus the RIPE NCC also provides a very simple API to customize your graphs or access the raw data from your probe. For instance this is a graph showing the RTT from my probe located near Paris to the K-root server in IPv6:

Graph of the RTT from the probe to the K-root server in IPv6

This is the kind of project that will lead us to have a better comprehension of the inner behaviors of the networks and improves it for the sake of all.
Kudos to the RIPE NCC team for the initiative.

irssi: remotely attach/create a screen in one line

Posted by on March 8, 2011 No comments

If you’re a big fan of irssi and you’re running it on a remote server over SSH and inside a screen, then I have a nice tip to share with you.

irssi logo

Just put the following line inside your .zshrc or .bashrc file:

alias rirssi='ssh user@your.server.com -t screen -dRUS irssi irssi'

This simple alias will allow you to:

  • Connect to your remote SSH server
  • Attach to your existing irssi screen named “irssi”
  • If the screen doesn’t already exist:
    • create a new screen
    • start irssi inside it
    • attach the newly created session

Pretty cool isn’t it? ;-)

Server migration: please welcome “Storm”!

Posted by on March 5, 2011 No comments

It’s been a long time (more than a year now) since I wrote my latest post on this blog and I feel very sorry for people who were waiting for some updates! I will try to write more often and regularly…

But today, I finally moved my blog from my ageing server to a new – blazing fast – Xeon Quad Core aptly called: Storm. Some important changes occurred behind the scene; previously the website was running on a simple Apache + mod_php configuration that was overloaded very often, mostly because I’m hosting some high traffic websites like this one.

Nginx logo

After some research I went to the conclusion that the combination of Nginx + php-fpm was the way to go. So I spent much of the past week doing some benchmarks using ab and I can confirm that it is very efficient, fast and still pretty stable. I’ve also leaved Gentoo Linux in favor of Archlinux which is more straightforward to maintain on a day-by-day basis. These days Gentoo became such a pain in the ass to keep the system up-to-date without breaking everything… which is rather annoying for a server without a physical access.

We’ll see how it goes in the upcoming weeks. I still have some other domains and applications to transfer before I can definitely shutdown the old server.

EDIT: Aww… and you probably don’t care but the ipv6 access is no longer available due to various routing issues with my provider, but anyway it will be restored ASAP.

Create an ebook using images on GNU/Linux

Posted by on July 12, 2009 2 comments

Today, my girlfriend had to create an Ebook (in pdf) using some images acquired from a scanner (using xsane). After searching a while on google how to do that I remembered that ImageMagick was the tool to manipulate images, so I gave it a try. Luckily (for me) it worked!

After this brief introduction, it’s time to share the two-steps solution with you.

Acquire the documents

The first step is to scan all of your documents using xsane. For a good quality use a DPI of 200 or more. You should name them accordingly to the order of inclusion. For example: 0001.png, 0002.png, …

Create the PDF

Now in a console, use this simple command to generate the ebook.

convert -define pdf:use-trimbox=true -compress jpeg -quality 95% *.png ebook.pdf

Remember that it can take some time if you have many pages.

That’s all folks !

VLC 1.0.0 Goldeneye

Posted by on July 7, 2009 11 comments
VLC Media Player

VLC Media Player

After more than a year of work, the VideoLAN community is proud to announce that VLC 1.0.0 is finally out !

This release has been delayed many times since February (the original release date chosen during the VideoLAN dev’days 2008) but reached its goal today. More stable, tons of new features, this release is definitely the best and most advanced release of VLC.

Take a look at the impressive changelog, and give it a try !

A list of the most *bling* *bling* enhancements since 0.9.9:

  • Increased stability
  • Reduced memory usage
  • Live recording
  • Instant pausing and Frame-by-Frame support
  • New HD codecs (AES3, Dolby Digital Plus, TrueHD, Blu-Ray Linear PCM, Real Video 3.0 and 4.0, …)
  • New formats (Raw Dirac, M2TS, …) and majors improvements in many formats…
  • New Dirac encoder and MP3 fixed-point encoder
  • Video scaling in full-screen
  • RTSP Trickplay support
  • Zipped file playback
  • Customizable toolbars
  • Easier encoding GUI in Qt interface
  • Better integration in GTK environments
  • MTP devices on Linux
  • Air Tunes streaming
  • And much more…

Download it now !

First post ever!

Posted by on July 3, 2009 2 comments

… no, just kidding.

As you can imagine this is not really my first blog post ever. As every geek on this planet I already owned thousands of (unmaintained) blogs before. This is just one more :-D

Now it’s maybe time to briefly introduce myself to my fellow readers !
I’m Ludovic, a 24 years old guy living in Paris with his girlfriend and a cat (yes, that matters). I’m a free software activist and developer, taking part in some small and medium-sized projects; but this will be the subject of an upcoming post. Last but not least, I’m also a KDE and VIM user (FTW) !

kthxbye.