Remove permanent redirect (HTTP 301) cache in Firefox

As a web developer configuring SSL certificates on websites you deliver, as we do, you might be faced, one day, with a small issue about configuring a 301 redirect from HTTP to HTTPS that has to be reverted. It so happens that browsers *really* take it to heart to cache an HTTP 301 (permanent redirect) message seriously and deeply. So much so that it might become very difficult to remove this redirect and ever be able to access the site in HTTP again.

Chamilo 1.11 on Raspberry Pi 3 for off-the-grid situations

This article can be considered an update of our first article on installing Chamilo (on a Raspberry Pi B+). This time, we are testing it with Raspberry 3, as of the 1st of April 2017 (no joke intended). Last time, we were testing with Chamilo 1.9, which is arguably less load-intensive, considering it doesn't include any Symfony component, and it doesn't require any .htaccess configuration.

Odoo apps licensing

If you ever want to implement projects with Odoo and, like us, you are a bit itchy about non-free-software licenses and alternative BSD or LGPL-like licenses, you might want to know this. Odoo itself was previously (as OpenERP) AGPL, but it apparently (following David from Odoo S.A.

Change SVG icons to grayscale with Inkscape

If you design your icons in SVG with Inkscape and wonder how to quickly make an "inactive" icon in grayscale, here's a quick fix (at least for Linux users):

inkscape -f teacher_na.svg --verb EditSelectAll --verb org.inkscape.color.desaturate.noprefs --verb FileSave --verb FileQuit

This will edit your file in-place (so you need to take a copy first) and will require Inkscape to be launched, but all in all, this will make you save a lot of time.

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

MySQL and MariaDB innodb_file_per_table

For those of you pushing your MySQL instances to higher levels, you'll have realized at some point that all InnoDB tables share their indexing space into a single file (ibdata1, usually). This has several very bad outcomes:
  • the ibdata1 file becomes huge after some time (we've seen it pass the 8GB bar)
  • starting the MySQL server takes longer
  • deleting an InnoDB table *doesn't* reduce the space used by ibdata1
  • you have to shutdown your server, remove ibdata1 completely, then restart the server in order to reinitialize the ibdata1 file to a 0-size file (but th

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