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grml-live(8)
============

Name
----

grml-live - build framework for generating a grml and Debian based Linux Live
system (CD/ISO)

Synopsis
--------

grml-live [-c <classe[s]>] [-t <target_directory>] [-F] [-h|--help]

*******************************************************************************
Important! grml-live is under heavy construction, though your feedback is highly
appreciated.  This document is growing as requested. If you have questions which
aren't answered by this document yet please let me know: <mika@grml.org>!
*******************************************************************************

Description
-----------

grml-live provides the build system for creating a grml and Debian based Linux
live-cd. The build system is based on
link:http://www.informatik.uni-koeln.de/fai/[FAI] (Fully Automatic
Installation). grml-live uses the "fai dirinstall" feature to generate a chroot
system based on the class concept of FAI (see later section for further details)
and provides all the details to be able to generate a full-featured ISO. It does
not use all the FAI features by default though and you don't have to know FAI to
be able to use it.

The use of FAI behind the curtains gives you the flexibility to choose the
packages you would like to include on your very own Linux live-cd without having
to deal with all the details of a build process.

CAUTION: grml-live does **not** use /etc/fai for configuration but instead
provides and uses /etc/grml/fai. This ensures that it does not clash with
default FAI configuration and packages, so you can use grml-live and FAI
completely independent at the same time!

[NOTE]

Please notice that you should have a fast network connection as all the Debian
packages will be installed via network. If you want to use a local mirror
(strongly recommended!) checkout mkdebmirror (see
/usr/share/doc/grml-live/examples/mkdebmirror), debmirror(1), reprepro(1) (see
/usr/share/doc/grml-live/examples/reprepro/ for a sample configuration) and
approx(8). To avoid downloading of the base system check out FAI's NFSROOT (check
docs for ../fai/nfsroot/live/filesystem.dir/var/tmp/base.tgz).

Options
-------

  -c **CLASSES**::

Specify the CLASSES to be used for building the ISO via fai.  By default only
the classes GRMLBASE and I386 are assumed, resulting in a small base system
(being about ~150MB ISO size).

  -s **SUITE**::

Specify the Debian suite you want to use for your live-system.  Defaults to
"etch"; support values are: etch, lenny, sid, stable, testing, unstable.

  -t **TARGET_DIRECTORY**::

Main output directory of the build process of FAI.  Three directories are
created inside the target directory, being: grml_cd/ - where the files for
creating the ISO are located (including the compressed squashfs file),
grml_chroot/ - the generated chroot system and grml_isos/ - where the resulting
ISO is stored.

  -F::

Force execution and do not prompt for / display summary of configuration
details.

  -h::

Display short usage information and exit.

  -v::

Increase verbosity in the build process.

How to get your own live-cd - the easy, fast and simple way
-----------------------------------------------------------

To get a small, Debian-stable and grml based live-cd using /grml/grml-live
as build and output directory:

  # grml-live

To get a small Debian-unstable and grml-small based live-cd using
/home/mika/grml-live as build and output directory:

  # grml-live -c GRMLBASE,GRML_SMALL,I386 -t /home/mika/grml-live

[NOTE]

If you have about 700MB of free space inside /dev/shm (being a tmpfs, usually
you have >=1GB of RAM) just run "mount -o remount,suid,dev,rw /dev/shm" and use
/dev/shm as build and output directory - resulting in very fast build process.
But please be aware of the fact that rebooting your system will result in an
empty /dev/shm, so please another directory for $CHROOT_TARGET, $BUILD_TARGET
and $ISO_TARGET if you plan to create more persistent output. :)

Features
--------

* create a grml-/Debian-based Linux Live-CD with one single command

* class based concept, providing a maximum of flexibility

* supports integration of own hooks, scripts and configuration

* supports use and integration of own Software and/or Kernels via use of Debian
repositories

* native support of FAI features

* multi-arch support (work in progress)

The class concept
-----------------

grml-live uses FAI and its class based concept for adjusting configuration
according to your needs. This gives you flexibility and strength without losing
the simplicity in the build process.

The main and base class provided by grml-live is named GRMLBASE. It's strongly
recommended to **always** use the class GRMLBASE when building an ISO using
grml-live as well as the architecture dependend class (being 'I386' for x86_32
currently only). The following files and directories are relevant for class GRML
by default:

  /etc/grml/fai/config/scripts/GRMLBASE/
  /etc/grml/fai/config/debconf/GRMLBASE
  /etc/grml/fai/config/class/GRMLBASE.var
  /etc/grml/fai/config/hooks/instsoft.GRMLBASE
  /etc/grml/fai/config/package_config/GRMLBASE

Take a look at the next section for information about the concept of those
files/directories.

If you want to use your own configuration, extend an existing configuration
and/or add additional packages to your ISO just invent a new class. For example
if you want to use your own class named "FOOBAR" just extend CLASSES="GRMLBASE"
inside /etc/grml/grml-live.conf to CLASSES="GRMLBASE,FOOBAR" or invoke grml-live
using the classes option: "grml-live -c GRMLBASE,FOOBAR ...".

More details regarding the class concept can be found in the documentation of
FAI (available at /usr/share/doc/fai-doc/).

Files
-----

Notice that grml-live ships FAI configuration files that do not use the same
namespace as the FAI packages itself.  This ensures that grml-live does not
clash with your usual FAI configuration, so instead of /etc/fai/fai.conf
(package fai-client) grml uses /etc/grml/fai/fai.conf instead. For more details
see below. To get an idea how another configuration or example files could look
like check out /usr/share/doc/fai-doc/examples/simple/ (provided by Debian package
fai-doc). /usr/share/doc/fai-doc/fai-guide.html/ch-config.html also provides
documentation regarding configuration possibilities.

  /usr/sbin/grml-live

Script for the main build process (being a wrapper around FAI currently).
Requires root permissions for execution.

  /etc/grml/fai/fai.conf

Main configuration file which specifies where all the configuration files and
scripts for FAI/grml-live can be found. By default it is
FAI_CONFIGDIR=/etc/grml/fai/config, a directory shipped by grml-live
out-of-the-box so you shouldn't have to configure anything in this file.

  /etc/grml/fai/make-fai-nfsroot.conf

TODO: documentation

  /etc/grml/fai/NFSROOT

TODO: documentation

  /etc/grml/fai/apt/sources.list

This file specifies which mirrors should be used for retreiving the Debian
packages used for creating the ISO. If you want to use a local mirror you have
to adjust this file.

  /etc/grml/fai/config/

The main directory for configuration of FAI/grml-live. More details below.

  /etc/grml/fai/config/class/

This directory contains files which specify main configuration variables for the
FAI classes.

  /etc/grml/fai/config/debconf/

This directory provides the files for preseeding/configuration of debconf
through files.

  /etc/grml/fai/config/hooks/

This directory provides files for customizing the build process through hooks.
Hooks are user defined programs or scripts, which are called during the
installation process.

  /etc/grml/fai/config/package_config/

File with lists of software packages to be installed or removed.  The different
classes describe what should find its way to your ISO.  When running 'fai -v -C
/etc/grml/fai -cGRMLBASE dirinstall ...' only the files from the directory GRML/
will be taken, if you use 'fai -v -C /etc/grml/fai -cGRMLBASE,FOOBAR dirinstall
...' then the files of GRML/ **plus** the files from FOOBAR/ will be taken. So
just create a new class to adjust it to your needs. Please notice that the
directory GRML contains a package list defining a minimum but still reasonable
package configuration.

  /etc/grml/fai/config/scripts/

Scripts for customising the ISO within build process.

  /etc/grml/fai/files/

This directory provides files used inside the scripts of
/etc/grml/fai/config/scripts/*. For a full documentation what happens with the
files please refer to the source of the scripts.

  /etc/grml/fai/live-initramfs/

This directory provides the files used for building the initramfs/initrd via
live-initramfs(8).

Requirements for the build system
---------------------------------

* any Debian based system should be sufficient (if not please send a bug
report), for example a grml2hd harddisk installation ships all you need

* enough free disk space; at least 800MB are required for a minimal grml-live
run (\~400MB for the chroot [$CHROOT_TARGET], \~150MB for the build target
[$BUILD_TARGET] and \~150MB for the resulting ISO [$ISO_TARGET] plus some
temporary files)

* fast network access for retreiving the Debian packages used for creating the
chroot (check out "local mirror" and "NFSROOT" to workaround this problem as far
as possiblbe)

Known TODOs
-----------

* make sure the suite-target adjusts the mirror definitions according (working
also vice versa!) and you can define the mirror more central (without having to
deal with /etc/grml/grml-live.conf, /etc/grml/fai/make-fai-nfsroot.conf and
/etc/grml/fai/apt/sources.list; debootstrap [FAI_DEBOOTSTRAP] vs. apt inside
chroot [sources.list] as well)

* document the available classes in more detail

* make sure $TARGET is mounted rw,suid,dev

* write a step-by-step guide **how** to adjust **what** at **which** place

* add support for amd64 [gebi?] + ppc [formorer?] (and identify all packages
that are arch specific so we have a clean package list in all classes)

* support different grml-flavours through classes right out-of-the-box (being:
grml, grml64, grml-small (in progress) for at least x86, amd64 and ppc)

* support signed apt repositories (currently it's deactivated via FAI's
FAI_ALLOW_UNSIGNED=1 for some packages in the toolchain)

* explain (and provide configuration for) use of NFSROOT

* support setting stuff like ISO name, version,... on-the-fly (especially for
stuff inside boot/isolinux/*)

* support "final builds" (including stuff like generating md5sums, gpg,...)

* the grml-live class(es) should send output as used inside FAI as well (so it's
not as verbose unless you specify it, make it configurable)

* provide possibility for cleanup of all created build directories and
a smart summary of the buildprocess (including "took ... minutes/seconds to
build...)

* support hooks to allow further customisation of the build process

* test the package on non-grml systems (and maybe even non-Debian) as well

Debian package
--------------

Debian packages will be available through the grml-repository at
link:http://deb.grml.org/[http://deb.grml.org/] as soon as the grml-team
considers grml-live as stable enough. In the meantime just build the package on
your own:

  hg clone http://hg.grml.org/grml-live
  cd grml-live
  debuild -us -uc

Source
------

The source of grml-live is available at
link:http://hg.grml.org/grml-live/[http://hg.grml.org/grml-live/]

Bugs
----

Please report feedback, link:http://grml.org/bugs/[bugreports] and wishes
link:http://grml.org/contact/[to the grml-team]!

Authors
-------
Michael Prokop <mika@grml.org>.

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