is a
Computer Operating System which runs entirely from a
CD or
DVD drive, without performing an installation process or using the hard drive. Knoppix is a
Debian based
GNU/Linux Distribution LiveCD , developed by
GNU/Linux consultant
Klaus Knopper .
Several factors contribute to the popularity of Knoppix:
When repairing systems with non-booting hard drives, Knoppix is a much more comfortable environment than the previous solution of
Boot Floppies , thanks to the complete graphical environment and networking.
Knoppix has a wide variety of
Free Software but includes also
Proprietary Software . More than 2600 software packages are included on the DVD edition and more than 1000 are included on the CD edition. Up to 9
Gigabyte s can be stored on the DVD in
Compressed form. When a program is used, it is decompressed into a
RAM Drive . The decompression is
Transparent and
On-the-fly . At least 128MB of
RAM is recommended in order to accommodate this RAM drive.
Unlike standard Linux distributions, it does not require a
Hard Drive Installation ; the system can
Boot from a single 4.7
Gigabyte DVD or a 700
Megabyte Compact Disc . One needs a bootable CD or DVD-ROM drive to start Knoppix from the CD. In order to start the CD/DVD, it may be necessary to enter the BIOS Setup of your computer and, in the boot order, select the CD drive before the hard drive or floppy drive. Insert the CD/DVD and restart the computer. The Knoppix start-up script goes through hardware autodetection and brings up the graphical user interface. When starting a program it is loaded from the CD or DVD.
Knoppix can also be installed to a hard disk with an
Ext3 partition. Users must switch to a root console and type "knx-hdinstall" or "knoppix-installer" in version 3.8. Installing Knoppix to a hard drive allows users to save files and let Knoppix be a more permanent OS.
There are several possible uses of the Knoppix live CD:
- an introduction to Linux, especially as a Desktop operating system
- Advocacy or demonstration at conferences
- in-store testing to determine whether a computer system is Compatible with Linux before purchase
- restoring a defunct system or some of its data
- running a Firewall or Router
- Bootstrapping an operating system installation
- Forensic investigation on hard drives
Prior to Knoppix 3.8.1, any documents or settings a user created would disappear upon reboot. This lack of permanence made it necessary to save documents explicitly to a hard drive partition, over the network, or to some
Removable Medium , such as a USB
Thumbdrive .
It was also possible to set up a "persistent home directory", wherein any documents or settings written to the user's home directory would automatically be redirected to a hard drive or removable medium, which could be automatically
Mounted on bootup. What is stored there physically is a file called ''knoppix.img''. The file is used to simulate a file system into which files are written for later use. This is transparent for the user. What the user perceives is that it is possible to write files to the home directory.
Since Knoppix 3.8.1, a
UnionFS Filesystem transparently saves any new or changed files to a writable
Filesystem - one which can reside either in memory (
Ramdisk ) or on a
Hard Disk , USB thumbdrive, etc.
This means that the user can modify the software installed on the Knoppix system, such as by using
APT to install or update software.
Additionally, Knoppix users can employ
Klik . The user can go to a web site and install and run programs simply by clicking on
Hyperlink s.
By carrying a Knoppix CD and a USB thumbdrive, a user can have the same environment, programs, settings, and data available on any computer.
Boot options are also known as cheat codes. Automatic hardware detection may fail, or the user may want to use something other than the default settings. For example, the user may wish to boot into
Xfce , or boot a plain console, or proceed without SCSI support. For this, Knoppix allows the user to enter one or more cheat codes at the prompt before booting. If the user doesn't enter a cheat code, or if no key is pressed before the timeout, Knoppix will boot with its default options. Cheat codes affect many auto-detection and hardware options. Many cheat codes also affect the GUI. The list of cheat codes is available on the Knoppix mirrors, and can be seen at boot time by pressing F1.
To set a language other than the default (CDs are available with either German or English as the default language), type your language abbreviation at the boot prompt. For US English, one would type:
knoppix lang=us
The
Graphics Card Device Driver is very important in using this distribution as it relies on a
Graphical User Interface , although most expert users can make use of the
Command Line Interface . If your graphics card does not work, it may be that it is new (or exotic) and is not in the knoppix hardware database yet. New cards will usually work under Linux, but they may have to be run using a generic driver, with a boot option like this:
xmodule=fbdev
Knoppix has three important drawbacks:
- Knoppix works on a fairly high number of PCs or laptops, but not all. The automatic hardware detection cannot cope with all hardware. Sometimes the drivers used will not be optimal. Knoppix being a LiveCD cannot be upgraded with driver upgrades easily. Knoppix has difficulty recognizing some cards made before 1998, or motherboards with a BIOS made before 2002.
- Memory usage: Knoppix requires at least 128 MB of memory to run the KDE environment, and even then Knoppix has long loading times when running from the CD or DVD. The need for large amounts of memory is a shortcoming that Knoppix shares with LiveCDs in general.
- Engaged optical drive: This is a common drawback with all live CD distributions. You cannot listen to an audio CD or watch a DVD in Knoppix if you have a single optical drive (as in a notebook).
One drawback of using Knoppix is that running the programs from the CDROM leads to long program loading time. There is a relatively straightforward way to accelerate work under Knoppix if an empty
FAT32 -partition is available. The Knoppix folder may be copied into this partition by using any operating system. When the Knoppix system boots, the CDROM or DVD is only used for loading an initial minimal system and then the switch over to the Knoppix folder on the harddisk is made for further work. This leads to straightforward upgrading of a new version of Knoppix. People just replace a folder on the harddisk partition. It is also possible to get the entire CD copied into RAM by using the "toram" option. However, this takes some time and requires enough RAM (1GB, CD version).
In addition, the CD or DVD may be removed after booting if this option is used.
Another option is to install Knoppix on the
Hard Drive , as described in the Usage section, so that the CD/DVD is never used.
Knoppix's relatively poor performance in this respect is generally not an issue, since the main reasons to use Knoppix do not include speed but rather having a working Linux system by just inserting a CD/DVD and perhaps a USB memory stick.
Sources:
http://code.campware.org/projects/livesupport/ticket/934
http://www.osnews.com/story.php?news_id=5589
http://www.osnews.com/story.php?news_id=5589&page=2
http://www.knoppix.net/wiki/Bugs/3.6-2004-08-16
The official list of mirrors hosting Knoppix ISO images for CD-ROM is available
here .
The DVD is available via
Rsync , using the command
rsync -avv rsync://ftp.gwdg.de/pub/linux/knoppix/dvd/KNOPPIX_V4.0.2DVD-2005-09-23-EN.iso
If that doesn't work, try
nohup rsync -avv --progress rsync://ftp.uni-kl.de/knoppix-dvd/KNOPPIX_V4.0.2DVD-2005-09-23-EN.iso . > getdvd.out 2>&1 &
The above command and site were working as of March 2006.
Nohup is suggested because the file may take about 20 hours to download.
There are indeed mirrors for the DVD, but they are very
scarce . This is because some FTP servers can't handle the capacity of these ISO images and may corrupt the download process.
In order to run Knoppix on your machine, you must have done the following correctly -
- burned the ISO file as an image onto a disc
- set the boot sequence/priority correctly so that your machine boots from the CD/DVD drive before it boots from another device with an operating system
Step by step instructions for successfully running Knoppix -
# Prepare for Knoppix: Restart your computer, and while it is starting up (more specifically, during the RAM check), enter your machines
BIOS by pressing the appropriate key (usually the DELETE key).
Change the boot sequence/priority of you machine so that the computer boots from the CD-ROM/DVD drive before it boots from any other device with an operating system on it. The best way to do this is by allowing your CD/DVD-ROM drive to be booted as #1 priority.
# Install Knoppix: Burn the ISO file available
here onto a CD-ROM or DVD as an image. This is different from simply burning the file as data to a blank disc. Go
here for a detailed guide on this process.
# Run Knoppix: Insert the CD/DVD you've created into the correct drive, and restart your computer.
Starting from version 4.0, Knoppix has been split into a DVD "maxi" edition (with over 9GB of software), and a CD "light" edition, both developed in parallel. The limited first edition of the Knoppix 4.0 DVD was handed out to visitors at the ends.
Knoppix has offered the Linux 2.6 kernel as an option since version 3.4; since version 3.8 it has been standard. Older versions of Knoppix default to a version of the 2.4 kernel.
- Accelerated KNOPPIX - takes only 60 seconds or less for a boot up from CD (depending on the hardware used)
- Auditor Security Collection is commonly used to test the security of networks. Auditor gives one Root Privileges .
- BioKnoppix targeted for the molecular biologist, intended for demonstrations, molecular biology students, workshops, etc.
- ClusterKnoppix is a distribution based on Knoppix using the Linux Terminal Server Project and OpenMosix . It is a convenient way to try out Clustering .
- eduKnoppix is an Italian Knoppix variation, aimed at primary schools. It focuses on children aged between 8-15, and thus contains a lot of educational software for kids. The other language supported is English.
- Games Knoppix is a Live CD with a lot of free games based on Knoppix with accelerated 3D support for ATI and Nvidia graphic cards.
- The Gnoppix project uses a modified form of Knoppix with GNOME as the default Desktop Environment .
- Kanotix Linux LiveCD is based on Knoppix, but mostly based on Debian Sid. The current version of Kanotix is 2005-04.
- Knoppix STD (security tools distribution) is a customized distribution of Knoppix that focuses on computer security tools.
- KnoppMyth is a distro that attempts to make the Linux and MythTV installation as trivial as possible.
- Kurumin is a Brazilian distribution based on Knoppix (with support for the English language), whose "Light" version fits on a Mini-cd . It includes standard desktop applications, documentation and an e-book that introduces users to Linux.
- Mediainlinux is geared toward multimedia production, based on Knoppix.
- ParallelKnoppix is a Knoppix-based LiveCD with support for netbooting (via PXE ) an MPI ( Message Passing Interface ) cluster off a single master node.
- Quantian scientific computing environment is a Knoppix-like DVD geared towards scientific, numerical and statistical tools, based on clusterKnoppix and offering openMosix clustering (as well as MPI/PVM clusters) out of the box or via PXE netbooting
- VigyaanCD Vigyaan is an electronic workbench for bioinformatics, computational biology and computational chemistry. Based on Knoppix, it has been designed to meet the needs of both beginners and experts.
