[plug] Root/Boot on Software RAID

[Grahame Bowland]

On 17 Sep 2001 14:28:07 +1000, Andrew Furey wrote:
> > All RAID devices are detected at boot when using a
> > standard partition as root, however the kernel
> > complains that it cannot read the superblock when
> > trying to boot with root=/dev/md0.
> 
> I presume you're using LILO to boot? The problem is
> not with /, so much as with /boot.
> 
> AFAIK, LILO can't boot off a RAID 1 device because it
> doesn't know how to handle it.
> 
> Try making a separate (non-RAID) boot partition. It
> should then grab the kernel image from that, set the
> root partition correctly, and you're away. If you set
> the boot device to be mounted read-only by default
> (and only remount read-write when you need to change
> it, if at all) it should be fairly crash-proof.

If you do this you loose the ability to boot should one of your drives
fail. Testing the Linux RAID we've found that it'll quite happily deal
with you yanking out a SCSI drive in the raidset while it's booted, then
shutdown and reboot on just one drive.

-- 
Grahame Bowland, Network and Systems Administrator
University Communications Services, The University of Western Australia
Phone: +61 8 9380 1175