[mdlug] Booting CD images from a hard drive partition

[Aaron Kulkis]

Drew wrote:
> I wish to set aside one or more partitions on the new hard drive for 
> holding a copy of
> a Linux boot CD, such as Knoppix, PC-OS, or RIPLinux, to have a copy ready to
> boot without needing to dig out the CD.
> 
> I've managed to get Grub, on the MBR and with its config files in 
> /dev/sda2, to boot
> into another copy of Grub on /dev/sda5 via rootnoverify / chainloader 
> +1; with that copy of
> grub giving a choice of kernels in Suse. I'm doing the same thing 
> with the master Grub
> for the CD image.
> 
> My menu.lst for the MBR Grub looks (partially) like this:
> 
> # Other bootable partition config begins
>    title DOS on (/dev/hda1)
>    rootnoverify (hd0,0)
>    makeactive
>    chainloader +1
>    title SUSE on (/dev/hda5)
>    rootnoverify (hd0,4)
> # makeactive
>    chainloader +1
>    title RIPlinux on (/dev/hda6)
>    rootnoverify (hd0,5)
> # makeactive
>    chainloader +1
> # Other bootable partition config ends
> # Linux bootable partition config begins
>    title Linux on (/dev/hda5)
>    root (hd0,4)
>    kernel /boot/vmlinuz root=/dev/hda5 ro vga=normal
> # Linux bootable partition config ends
> 
> Selecting the Suse option that uses the chainloader command works as 
> expected. Presumably
> it just jumps to the very beginning of /dev/hda5 where the other copy 
> of Grub picks up and does
> its thing. Now to get the RIPLinux option to do the same thing.
> 
> First attempt: Simply dd the CD onto the partition, then try to boot 
> it. I got "isolinux.bin missing
> or corrupt".
> 
> Next I tried map (cd) (hd0,5) and map (hd0,5) (cd) at which commands 
> it choked. So I took them
> out.
> 
> Then I copied the CD to a directory, changed all instances of (cd) to 
> (hd0,5) in its boot/grub/menu.lst,
> and made a new CD image with mkisofs, following the directions in 
> boot/doc/isolinux.txt on the CD.
> I dd'd that to the partition and tried booting it. Back to 
> "isolinux.bin missing or corrupt".
> 
> I then processed the image with the 'isohybrid' script on the CD, 
> then again dd'd it to the partition.
> Same result. Also same result doing isohybrid on an unchanged iso copy.
> 
> Okay, what do I need to do to get it to find the isolinux.bin file?
> 
> BTW: I am aware that there is an "install to hard drive" option when 
> the CD itself is booted. I'd
> rather not use that if I can avoid it; I rather like the 'it's a 
> fresh system every reboot' aspect of booting
> from the CD. I just want to do it without actually using the CDROM drive.
> 

Why not just copy the CONTENTS of the iso filesystem onto
a native filesystem (say, ext3) on a partition, and boot that?

You sound like someone who is says they want to get to the
top floor of a skyscraper and want to know what path to take
up the outside wall of a skyscraper, completely ignoring the
fact that there are staircases and elevators already in
place for precisely that purpose.

The solution is NOT to cram a square peg into a round hole.
use mkfs to create a filesystem on the partition, mount
the .iso file, and then boot that partition.

This is very simple.  The only thing difficult is your
insistence upon a really, REALLY sub-optimal choice of
configuration elements (i.e. using a .iso file as the
system to boot off of).  ISO's have a lot of limitations,
beyond the particular one you're facing at this point.