[lug] boot CD options

[Nate Duehr]

On Thu, Jun 21, 2001 at 12:37:20AM -0600, D. Stimits wrote:
<snipped...>

> What causes the 2.88 MB limit? Is it just a limit of mkisofs, or is it
> built in to iso9660 filesystems? I was hoping to do something slightly
> more flexible...create a complete bootable system on CD, with a /boot
> directory that has a fairly unconstrained kernel and a lot of modules in
> /lib/modules. Is there some sort of spec for the artificial support of
> CD booting whereby it isn't really just an IDE drive during boot (my
> cdrom and most these days are IDE ATAPI)?

It's a limitation of the bootable CD standards, not of the hardware.  

> I could see the possibility of simply mounting my own (extra large)
> ramdisk on a temporary mount point, and manually copying anything I need
> into the ramdisk, including kernel images; then running lilo after doing
> a chroot to the ramdisk, followed by dd of the ramdisk to a regular file
> that has been formatted like an iso9660 filesystem. This image could
> then be transferred to the machine with the cd burner. Or could it? I'm
> not quite sure of what the real limits are for booting CD's, but I'd be
> happier if I could use at least 3.5 MB for kernel plus initial ramdisk,
> along with glibc and a lot of extra repair style tools.

There's a project (I can't remember the name of right now) up on
SourceForge that has four or five bootable CD images done -- their goal
was to create useful bootable "emergency boot" CD's.  Darn if I can't
remember their name right now...

But if you found that (probably a search there for "bootable CD" would
work) you could look at how they did it.  I think they were using
SYSLINUX as the bootloader from CD, and doing similar to what you
mention above.

-- 
Nate Duehr <nate at natetech.com>

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