Building kernel for another computer

[Gary <gldu@garydjones.mailshell.com>]

I need to build a newer kernel for my laptop in order that it will support a
parallel network interface I have for it. Since my only way of getting
anything onto the laptop is via floppy, what I did was build a suitable
kernel on my potato box (yes, I know, that's old as well! it is not as old
as 1.3 that is running on the laptop at the moment, however...), and copied
the result onto a floppy. I then try and boot the laptop from the floppy (I
want to be sure the kernel works okay before I replace the one on the hd).
Everything goes well until it reports a kernel panic because it is "unable
to mount root fs". Obviously I've missed a step somewhere. Would someone
please give me a pointer to where? None of my books have anything in them
regarding building kernels on one computer to run on another.

I think that I can just add an extra lilo entry on the laptop, copy the
kernel on to the lappy's hd and try it out that way, but I think I'd rather
learn what step I am missing first (sometimes it is useful to know how to go
over the mountain as well as knowing the route around).

Thanks folks.