> I will re-read it, I'm glad I'm headed in the right direction.
> Is there anything else that might help me with the process? Any help
> at all would be greatly appreciated.
Just this, from bitter experience: build everything so it boots from a
USB stick first, and then write just your filesystem to a non-bootable
CD second. Then, when that works, build a livecd. This avoids making a
million coasters and costing you a king's ransom in plastic whose only
value is sparkling and cracking in the microwave.
Disclaimer: None of the following is specific to LFS, and it all has
to do with live cds and problems you'll run into on any linux at all.
A USB stick can be partitioned just like a hard disk (provided you
don't try to read it in a windows machine even if it has ext3 support;
windows just can't read partitioned disks), and grub can be installed
into the root of the device. So the process is identical to a hard
disk install.
What isn't identical, is your module configuration. This is where that
"works" thingie you were talking about comes into play. Your kernel is
going to have to be able to configure your device drivers. In order to
do that, it needs to recognize your device drivers. Which means,
before you, the user, ever touch the keyboard or type command #1 in,
your computer has to run modprobe a few dozen times. To make matters
more complicated, there are a few cases where probing the wrong driver
on the wrong hardware hard locks your computer and/or makes your
kernel panic.
The beauty of setting things up this way, is that if it doesn't work,
you just tweak a couple things and try again, no cds or dvds being
thrown into the garbage.
My favorite way of working all those miracles is with an initrd.
Chances are your favorite distro does things exactly the same way. To
make one, go into a directory you want to be your root directory, and
then do this:
mkdir -p lib/modules/
cp -r /lib/modules/2.6.[kernel version] lib/modules
cat > init << "EOF"
#!/bin/sh
MODULES=
ROOT=/dev/sr0
ROOTTYPE=iso9660
for module in $MODULES
do
modprobe $module
done
mount -t $ROOTTYPE $ROOT /newroot
if [ -x /newroot/sbin/init ]
then
umount /sys /proc
exec switch_root /newroot /sbin/init
else
echo "init not found, dropping to debug shell"
/bin/sh
fi
EOF
mkdir {newroot,dev,sys,proc,bin}
Then, drop a static shell (busybox might be tempting here, but the
question that led me to this list involved busybox sucking with
kernels > 2.6.26, dunno if they ever fixed the way it looks up device
drivers) (to compile a static shell, make coreutils with the
CFLAGS=-static and CPPFLAGS=${CLFAGS} options) in ./bin
Now, to make that initrd, it's
find . | cpio -H newc -o | gzip - > ../initrd.igz
And, to open it back up and modify it, it's
zcat ../initrd.igz | cpio -i
which will dump the contents back into the current directory.
Grub has instructions and support for using that initrd with your kernel.
That script I gave you won't work the first time, by the way. It's
designed to drop you down to a shell that will let you run modprobe,
etc, look at your device drivers, and do whatever you have to do to
get your system to boot. Once you're inside your system, you can open
up and modify your initrd so that your script will repeat whatever
steps you took to get into your system. Since your system is on a CD,
that means that when you do decide to make a live CD, every driver and
part of your system will already be working properly, and if it
doesn't just to spite you, you have a tool for getting it to work.
At the end of the day, it limits the number of CDS you have to burn
before everything works to 3.
To get a device driver to work, look in /lib/modules/2.6.[kernel
version]/kernel for a file that ends in ko, and then do this
modprobe `basename ${file%.ko}`
To get it to show up, you're probably going to be relying on your udev
daemon or a script (this was precisely where busybox failed me; its
mdev script just couldn't make heads or tails of the way linux moved
stuff around in /sys). A good trick to see if your kernel is
recognizing something that udev isn't is this
lsusb
and another one is
lspci
if either of those say anything about your hardware (manufacturer,
whether it's a wireless card, etc), your hardware is working, your
kernel module is loaded properly, and udev is dropping the ball.
All that sounds a lot more complicated than it is (sorry about that),
but it all boils down to this:
Make a bootable usb stick, THEN make a livecd
Good luck :D Let me know how things go for you, I know my e-mail addy
is funny looking but it's real and it works, and remastering livecds
in general (not specifically LFS, I started with DSL and Knoppix) is a
wall I've been beating my head against for a while. Please feel free
to ask me any questions not directly related to BLFS, especially
related to remastering. Helping you helps me.
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