[NCLUG] Build a Linux kernel for a 486 machine.

[Michael Dwyer]

> I want to set a 486 machine as a router/gateway machine. Is it
possible?
> What is the minimum requirement for this PC(Memory, Hard drive etc)?

Minimum is i386, about 8MB, and I'm not sure about the HDD requirements.
Suffice to say, if you are just running a router/gateway, you can fit
everything on a floppy.

Matt makes an excellent suggestion about checking out the linux router
project.  You might also look into the Linuxcare Bootable Business
Card -- They have links to a number of tiny linux distros.

I ran on a 386/16 with 16MB.  It took most of the day to compile a
kernel on the machine. :)  But it worked fine.  I used the A and N sets
of Slackware, for basic support plus some networking.

> I guess I could build the kernel on a faster machine and transfer it
to the
> 486 machine. Could anyone tell me how to build and transfer over if
there is
> no network before loading the kernel? Do I need build each components
as
> part of the kernel instead of a module loaded in when needed?

Building all your drivers into the kernel certainly make it easier, but
you cannot build everything in.  I believe that some of the firewall
modules (for ICQ, FTP, etc) can only be built as modules.
Usually, you do this:
   make clean
   make mrproper
   make xconfig   #or menuconfig
   make bzImage
   make modules
   make modules_install

This will generate the actual kernel in arch/i386/boot/bzImage, and
install all the modules you need in /lib/modules/<kernel version>/  I
usually tar these up, grab the bzImage file, and the System.map file and
move those over to the other machine.  Floppy works, if you have no net
yet.

Once at the other machine, I untar the modules in the right place, put
System.map in the boot folder, rename bzImage to /vmlinuz.new or
something, edit lilo.conf to match, run Lilo -v -v  and away I go!

Mind you, there's a bit more to it than I show.  Compiling your own
kernel is an art in itself.