On 30 Oct 2006 21:33:36 -0800 rangi wrote:

| Hi please let me know, how to build a single boot CD/DVD supporting x86
| and IPF(ia64) in linux.
| iam not getting how to approch this. weather we have to make changes in
| boot loader code or some where else. iam waiting for your kind
| information.

This is actually easier to do when two very different architectures are
involved. For example I've built CDs that can boot Linux on either x86 or
Sun Sparc using the very same CD for either. The "trick" is that each
architecture looks in a different place for its boot loader and subsequently
loads a different kernel image and different initial ramdisk, which can in
turn be programmed to mount a different file tree from the CD, and either
load it into tmpfs or ramfs, or pivot that mount point to the root.

The problem you have is that you're dealing with effectively the same
architecture in terms of how it initially loads an operating system. At
some point things need to be distinguished, but you don't get to do it at
the initial boot loader. Somewhere between when the boot loader begins
running to the point you wish to have the appropriate kernel running,
something has to make the decision and take the action steps necessary to
run the appropriate kernel. Maybe a boot loader like grub could be
configured, or hacked, to do this. Another option is to run a 32 bit Linux
and run a program that can somehow figure out the CPU really is a 64-bit
one, and use the "kexec" fature in the kernel (only needs to be in the 32
bit one) to load a new kernel image that is the 64-bit one, along with a
different append string to select a different filesystem (or subdirectory if
you have a patch I wrote) with the 64-bit userland programs and libraries.

About kexec:
http://www-128.ibm.com/developerwork...y/l-kexec.html

Package "kexec-tools":
http://www.xmission.com/~ebiederm/files/kexec/

The patch I wrote referenced above:
http://phil.ipal.org/linux/kernel/pa...r-2.6.18.patch

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