The complete guide to screencasting in Ubuntu 14.04 + Gnome Shell

For those developers of you wanting to do more than just develop under Linux, you'll have realized that there are many things stopping you for doing proper video tutorials as easily as you would do it with some non-free (as in freedom) software. Fear not, though, as this tutorial, written at a time between Ubuntu 14.04 and 14.10 with the Gnome Shell, will help you go through it and hopefully setup a perfect environment that you will be able to re-use anytime, anywhere (with your laptop).

YouTube requirements

In order to prepare a good video tutorial, the first thing you need is: stan

Using php5-memcached to store sessions on distributed servers

This article is an extension of the previous article about storing sessions in Memcached with PHP. Using Memcached for sessions storage is generally a matter of speed (storing them in memory is faster than on disk) and of scalability (using a Memcached server allows you to have several web servers serving the same PHP application in a seamless way). In the previous article, we mentioned (3 years ago) that the php5-memcached extension did not seem to manage the storage of sessions quite well, or at least t

Using Chamilo juju charm to setup a dev environment on Digital Ocean

If you're in a hurry/on speed, know this:
  • this procedure is slightly more difficult (so longer) than installing the charm on Amazon
  • you can skip directly to "Installing Juju"
  • if you already have juju installed, you can skip to the last 2 lines of the "Installing juju" section
  • if you already have juju-docean installed and configured, you can skip directly to "Provisioning VMs"
  • otherwise, just continue reading, it's worth a few minutes...
This tutorial regroups a lot of advanced notions, so if you want to know more about one of the follo

Server stalled on Loading Kernel Modules without chroot - What to do?

Today we had a server stalled on "Loading kernel modules" at reboot (after adding 12GB of RAM, to 24GB total). The datacenter didn't know what to do and they put us on a 32-bit rescue mode console from which we couldn't (obviously) launch a 64bit chroot to update the kernel. The situation seemed pretty desperate. Our sysadmin, Jérôme, once again came to the rescue. Waiting for the datacenter to respond would have potentially increased reboot time up to 45 minutes. The only possible thing to do: replace initrd with a similar version (just in case the first one would have been damaged).

Adobe Flash and V4L2 webcams

Many new videoconference systems nowadays are Flash-based. Of course, the main input for them is some sort of video device (e.g. a webcam). Under Linux, the framework responsible for this is Video4Linux (V4L), of which version 2 (aka V4L2) is current. That means that most recent webcams drivers are supported only by V4L2. Alas, some proprietary editors (of which Skype and Adobe with Flash) still only support V4L1.