Building minimal linux from scratch

[Qwerti]

Hi,

I'm trying to understand a little bit more what is hidden behind the word "kernel", so I'm trying to complie it and install it. I'm having some little troubles though.

My goal is to have a minimal kernel on a USB drive with a bash and the very basic commands like ls, cp, mkdir, ... for now. If I get that working I'll be so happy!

I partitioned a 4GB USB drive into 4 partitions: 3 partitions of 500MB each in ext3 and the rest in vfat. On the first partition there's GRUB and a small distribution of debian which works fine. The two other ext3 partitions are where I'll test kernels and all that.

So what do I do?

I have the latest kernel : 2.6.22.2.

I should compile the kernel with all the appropriate options, right?

Ok, I don't know what "appropriate" means so I compiled it with the defconfig configuration. Now what? I have a file bzImage that I copy in the /boot directory of my "test" partition.

From grub I launch something like:

root (hd0,1)
kernel /boot/bzImage ro

and it fails!

I am a newbie so there are lots of things I'm missing: maybe specify root=/dev/sdax somewhere, maybe create a /dev/fstab file, maybe an initrd.img file? But what are these things? Any explanation and help is warmly welcome!!! I tried to read some documentations but I haven't seen any answers to my (stupid) questions.

Thanks,
Qwerti.

[oz]

Check out Linux From Scratch:

Welcome to Linux From Scratch!

It goes into lots of detail about Linux and how it's all put together.

[oz]

oh... another good option for learning to build your own is Rock Linux:

Main Page - RockWiki

[Qwerti]

Thanks a lot ozar! I was particularly by LFS... even though it's not exactly what I want to do it gives me nice ideas.

But now I'm having another problem, I can't compile anymore (see a new thread I just posted)...

I'll come back to my "tiny" linux as soon I this problem get fixed.

Thanks,
Qwerti.