On Thu Apr 16, 2009 at 05:47:10PM -0700, Timothy D. Lenz wrote:
> Welllll, tried to switch the other system over to raid boot and
> something went wrong ether with the copy or with menu.lst change or
> with grub, I think. I changed the boot order moving the ide below the
> 3 sata drives and before the grub boot menu came up I got an "error
> 2"
>
> This system is booting from hda1 and will be booting from md0 like the
> other system. This system has 3 sata drives, so md0 and md1 where
> setup has raid1 plus spare.
>
Why have a spare? You'd be better running 3-drive RAID1 arrays.
> To set up group I used:
> sudo grub --no-floppy
>
> Grub> device (hd0) /dev/sda
> Grub> root (hd0,0)
> Grub> setup (hd0)
>
> Grub> device (hd0) /dev/sdb
> Grub> root (hd0,0)
> Grub> setup (hd0)
>
> Grub> device (hd0) /dev/sdc
> Grub> root (hd0,0)
> Grub> setup (hd0)
> Grub> quit
>
> it gave me errors for sdc because it is not formated as formating was
> done on after the array was made. I assume that madadm will take care
> of boot setup if it activates it?
>
Not sure what you mean here, but you _must_ have the root filesystem
available before running grub. What the setup command in grub does is
install the stage1 bootloader (in this case to the MBR), setting a
pointer to the on-disk location of the stage 1.5 bootloader (which
includes the relevant filesystem support, allowing the stage 2
bootloader & menu to be read). If the stage 1.5 bootloader is moved
on-disk (or doesn't exist in the first place) then booting will fail.
I'd recommend:
- growing each of the arrays to 3 disks. This will give improved
performance; remove the lack of redundancy when a drive fails (as
you don't have to wait for the array to rebuild); and ensure the
3rd disk is actually working (having the drive fail during a
rebuild is not a nice experience). The downsides will be a
slightly increased power usage, and increased wear on the drive
(though I've not heard any concrete evidence that this actually
has any impact on drive failure).
- rerun the grub setup for all drives (once the arrays are all
synched). This will ensure the boot loader is pointing to the
correct on-disk location.
HTH,
Robin
--
___
( ' } | Robin Hill <robin@xxxxxxxxxxxxxxx> |
/ / ) | Little Jim says .... |
// !! | "He fallen in de water !!" |
Attachment:
pgpRVkwIi1YPh.pgp
Description: PGP signature
