Nanobsd on a CD-ROM

J. Porter Clark jpc at
Fri Jun 13 13:24:11 UTC 2008

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
> |>
> |>
> |
> | 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>

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