Re: raid1 bootable disks
On Fri, Aug 04, 2006 at 10:28:11AM +0100, A J Stiles wrote:
> If you use the "normal" method to install a bootloader on sdb, then you will
> end up configuring it to boot from sdb. But the way most motherboards work
> is that, if the first drive fails Power On Self Test, then it will be ignored
> and the second drive will be assigned as sda. So the bootloader on the
> second drive must be configured to boot from sda.
> Fortunately, you already have a bootloader configured to boot from sda on sda;
> so you can just use dd to copy the entire boot partition from sda to sdb.
All grub does from the MBR code is read and run code from other sectors
on the same disk. It doesn't know or care what disk it is on right now.
The kernel might care, but that isn't a grub problem.
Last I installed grub, doing grub-install /dev/sda and /dev/sdb,
resulted in two identical MBRs. I diffed them to be sure at the time.