Newsletter Volume 1 Livecd

Luca Casagrande

luca.casagrande@gmail.com

http://ominiverdi.org

Introducition

What is a Livecd

As Wikipedia report, liveCd is a "is a generic term for an operating system distribution that is executed upon boot, without installation on a hard drive. Typically, it is stored on bootable media such as a CD-ROM (Live CD), DVD (Live DVD), USB flash drive (Live USB), among others". using this kind of application user can get a "taste" of a full Linux box without fighting with any setup or installation. Once the liveCd has been booted, everything it's loaded in the RAM keeping safe the hard disk. Of course, as soon as the machine it's shuted down, every change it's lost.

Tasks

There are many application that can be satisfied by a livecd:

1. Using your favorite application everywhere you can find a pc
2. Teaching purpose: people can have machine with the needed software in a boot time
3. Using old machine: livecd can be run on smooth machine and also without HD.
4. Showing project: it's a very cool way of spread your work aroun. You deliver your work ( for example data ) and all application needed to appreciate it !

Limitation of a Livecd

When building a livecd, it contains both the kernel, the drivers, the WM and all the applications. Of course is pretty impossible to put all the driver that are used for all the machine, so can happen that, during the boot the cd stops or something else goes wrong (missine lan detection for example). During the years, have been created very good tool that detect the hardware during the boot, but, like every software application, there can be still bug. So you must see a failing boot, as a crash..that will be fixed soon.

The other thing that should be clear, it's that no information it's saved while working in the livecd enveiroment. This is good from a side ( for example for keeping safe your data) but can be thedius for another way. The solution for this is use a Storage Device (like an USB HD for example) to store all your output.This approach could also be used to save configuration file, so that you can have the same setting at every boot.

Livecd and open source geospatial software

Choice

While planning the first relase, we decided those points

Technical Description

For building the livecd, we decided to use Catalyst, the tool used by Gentoo Release Team. this choices come from 2 points:

1. Catalyst allow full customization
2. Upgrading the softwares

This tool allows the creation of "highly customized liveCd" about architecture and softwares. Catalyst uses a text file that contains information about how creating the liveCd:

• Architecture to use
• Software to add

Each application can be built with a custom configuration, adding or removing item from the default configuration:

[..]
sci-libs/gdal -png gif
[..]

This mean that gdal will be built using default configuration with gif support, but not with

png support.

Once the application list is read the softwares are installed using the configuration information described inside a file called packages.use

Future Development and task

Our goal is to keep the cd updated, creating new version at regular times, or at least as soon as major update or included softwares will come out.

Right now we are working on two tasks:

1. An Installer for the livecd
2. A server edition with mapserver and some webgis application

LiveCD installer

The installer will be accessible trough an icon on the desktop. The installation process will guide the user to the set up of the linux distribution in his computer. Installing on the hard disk will allow better performances and the possibility to update all packages thanks to Gentoo systems.

Server Edition

The server edition will target a server machine with minimum graphical support but full featured set of application to offer OCG Web Services and UMN Mapserver front ends (ka-Map, Open Layers, p.Mapper, ecc.).

More Infos

• Ominiverdi Livecd Project
• Gentoo Catalyst Project