Nanobsd on a CD-ROM

[J. Porter Clark]

On Thu, Jun 12, 2008 at 06:54:45PM +0200, Pietro Cerutti wrote:
> 
> 
> J. Porter Clark wrote:
> | On Thu, Jun 12, 2008 at 04:40:25PM +0200, Pietro Cerutti wrote:
> |> J. Porter Clark wrote:
> |> | Is it possible to build a CD-ROM with a bootable NanoBSD on it?
> |> | If so, how?
> |>
> |> Yes, Section 2.2 of
> |>
> |> http://www.freebsd.org/doc/en/articles/nanobsd/index.html
> |
> | Well, no, because I can't do this:
> |
> |   # dd if=_.disk.full of=/dev/acd0 bs=64k
> |
> | If I do this:
> |
> |   % cdrecord -v -immed driveropts=burnfree dev=1,0,0 -data _.disk.full
> 
> Try with burncd
> 
> | burncd -f /dev/acd0 data _.disk.full fixate

No joy.  Produces the same disk that cdrecord does, and boots
from hard disk instead.

I think that this is the problem: The BIOS knows how to boot
from a CD if and only if that CD is an "El Torito" bootable
image.  That is, the first sector of the CD is NOT a Master Boot
Record.  That's just a hypothesis based on the observation that
all of the successfully bootable CDs I have appear to be in "El
Torito" format.

I don't have a way to make such an image without using mkisofs.
Figuring out how to pack the nanobsd image in such a way that
mkisofs can make an "El Torito" bootable CD from it sounds
difficult, offhand.  Anybody know how to do this sort of thing?
Is it even possible?

-- 
J. Porter Clark      <jpc at porterclark.com>