[CentOS] 75% - 80% Rebuild Complete

Thu Jun 7 16:40:01 UTC 2012
Bowie Bailey <Bowie_Bailey at BUC.com>

On 6/5/2012 7:21 PM, Eugene Poole wrote:
> OK,  I'm about 90% sure that I've corrected the boot loader situation 
> with RAID-1 and the second hard drive.  I haven't tested the correction, 
> but here's what I did:
>     Examined the grub.conf file and noticed that hd0 uses (hd0,1), so
>     what followed was
>     grub
>         grub> device (hd1) /dev/sdc
>         grub> root (hd1,1)
>         grub> setup (hd1)
>         <after receiving the successful message>
>         grub> quit
> I didn't rebuild the boot loader on /dev/sda because it is working (if 
> it ain't broke don't fix it).
> My situation is that I'm using 4 - 1 TB hard drives and I used the 
> following pattern:
>     /dev/sda | /dev/sdc = First Raid -1 volume
>     /dev/sdb | /dev/sdd = Second Raid-1 volume

There is no complete solution to this problem.  The question is this: 
When one of the drives dies, how will the system see the remaining
drive?  Will it still see it as sdb, or will it now see that drive as
sda?  These situations need different grub configs.  I generally
configure both drives as if they were hd0/sda.  That way, if sda
crashes, I can remove the disk and boot the second drive normally.