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Linux on more than one PC104 won't boot

Help!

I have a port of Debian Sarge running from compact flash on a PC104 board. Everything is great. But now my boss wants to support another PC104 board that maps the compact flash to a different ide interface. So first board the CF is on IDE0,1(/dev/hdb), the second board is mapped to IDE1,0 (/dev/hdc).

How can I use the same distribution (same CF card) on both boards without editing the boot=/dev/hdb1 and fstab entry's. There must be a way to detect what drive is the first in the system (hdb or hdc) and tell grub or fstab to use that instead.

If I could solve the fstab problem at least I could edit the boot parameter in grub and be able to boot the CF card on a different PC without first modifying the card.

thanks for your help.

David Tucker

Reply to
david.tucker
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Hello,

That is no big problem, because you can append a /root/ directive to the kernel, where to find the root filesystem. In my case this is root=/dev/hda2 (which works because lilo maps these old names, too).

If you can tell grub per board (instead of per compact flash card), it would be easy. Otherwise you could try to boot from both devices - if booting from hdb fails, try booting from hdc. Another idea might be to create two boot menu entries for which root partition to use.

Otherwise my idea would be to create an initrd (or initramfs), which detects the device after booting (trying to mount) and then switch the root device over and continues booting.

I use devfs for my experiments with linux (but i486 architecture). Then I get a /dev/root device as my root filesystem. This I simply add to the /etc/fstab and everything is done; I don't need any direct reference to /dev/ide/host0/bus0/target0/lun0/part2 (in my case). LILO finds itself in the mbr...

Reply to
Sebastian

Thanks,

It looks like udev has replaced devfs for the 2.6 kernel. So I will give that a try.

In grub (hd0) maps to the first drive available. not just IDE0,0 Is there no way to map that back into a /dev/hdx reference? it sure would be nice if I could do this without editing grub (but not the end of the world)

David

Reply to
david.tucker

Ok, found a better solution, You can give your partitions 'labels' (using e2label for ext2/3) and thain in your fstab just replace /dev/hdx1 with LABEL=WHATEVER. This works like a dream, its exactly what I was looking for.

In theory this works for the root=/dev/hdx1 parameter as well just replace with root=LABEL=WHATEVER Sadly it does not seem to work on Debian.

David Tucker

Reply to
david.tucker

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