First Preparation

First create a directory where we will build the whole project. I chose the name myboot. Make an environment variable with the name MYBOOT, that contains the name of this directory. It is advised that you assign this variable from a script. I will use this variable throughout the document. Type the following commands in your home directory (assuming you use the bash shell):

mkdir myboot
export MYBOOT=~/myboot

Obtain the following source packages and collect them into the directory myboot:

• The Linux kernel. In our example we take version 2.4.21, which was the latest version at the time of writing. It may be desirable to use a kernel from the 2.2 series instead as it requires less memory. Even a kernel from the 2.0 series may do the job, it's still maintained, but don't ask me for how long. Download it from the main kernel site.
• The small C library uClibc. This can also be downloaded from the main kernel site, the kernel archive, the libs subdirectory.
• The shell and utilities Busybox.
• The utility programs in util-linux. These can be found at the main kernel site in the kernel archive, the utils subdirectory.
• The package e2fsprogs with programs to create and repair file systems.
• The ncurses library.
• The dialog utility.
• The keyboard utilities in the kbd package. These can be found at the main kernel site in the kernel archive, the utils subdirectory. This is essential if you live in a country (such as Belgium or Germany) where they don't use the one true QWERTY layout.
• The GRUB boot loader.

Some of these packages may already be present in your Linux distribution (in source form). For all packages except uClibc and Busybox this is very likely. But of course there may exist more recent versions.

After you have downloaded all the sources, your myboot directory may look like this. Of course you may have different (more recent) versions of all programs:

total 38572
-rw-r--r--    1 lennartb users      626209 2003-06-08 12:58 busybox-0.60.5.tar.bz2
-rw-r--r--    1 lennartb users      215806 2003-05-29 19:03 dialog_0.9b-20030308.o
rig.tar.gz
-rw-r--r--    1 lennartb users     2959524 2003-04-22 01:40 e2fsprogs-1.33.tar.gz
-rw-r--r--    1 lennartb users      877112 2003-03-24 17:14 grub-0.92.tar.gz
-rw-r--r--    1 lennartb users      819924 2003-06-08 12:36 kbd-1.08.tar.gz
-rw-r--r--    1 lennartb users    28533733 2003-07-06 13:16 linux-2.4.21.tar.bz2
-rw-r--r--    1 lennartb users     2067718 2003-03-24 17:24 ncurses-5.3.tar.gz
-rw-r--r--    1 lennartb users     1501374 2003-07-13 13:17 uClibc-0.9.20.tar.bz2
-rw-r--r--    1 lennartb users     1839967 2003-06-08 12:52 util-linux-2.11z.tar.gz

So let's unpack what we've got. Type the following commands when inside the myboot directory:

bunzip2 -c busybox-0.60.5.tar.bz2 |tar xvf -
gunzip -c dialog_0.9b-20030308.orig.tar.gz |tar xvf -
gunzip -c e2fsprogs-1.33.tar.gz |tar xvf -
gunzip -c grub-0.92.tar.gz |tar xvf -
gunzip -c kbd-1.08.tar.gz |tar xvf -
bunzip2 -c linux-2.4.21.tar.bz2b |tar xvf -
gunzip -c ncurses-5.3.tar.gz |tar xvf -
bunzip2 -c uClibc-0.9.20.tar.bz2 |tar xvf -
gunzip -c util-linux-2.11z.tar.gz |tar xvf -

After this you should have the sources of the nine packages, each in its own subdirectory.

Note: the $MYBOOT shell variable must point to the myboot directory.

Note: in this document you see many sequences of shell commands. Of course you can put them into shell scripts, so you need not retype them when you try to build a modified boot disk.