[CentOS] Raid Cards

[Les Mikesell]

On Thu, 2006-06-08 at 14:15 -0500, Steve wrote:
> >
> >If you have a problem booting, you can boot the 1st install CD
> >in rescue mode and fix the grub setup - and 'cat /proc/mdstat' will
> >always show you if the mirrors are active.
> >  
> >
> I'm using software raid1 /, /boot, and swap partitions on CentOS 4.3. 
> I've heard tell that the installer does not get the grub install/config 
> quite right.  i.e. if the first drive fails the system won't reboot.
> 
> Can someone tell me for sure what ai need to do?  Is it just something 
> like grub-install hd(1,0)?

I haven't installed on raid from the latest version so it may be
fixed now, but generally mine haven't even installed grub right on
the first drive of the set.  But, it is fairly easy to fix by hand.
You can either ctl-alt-F2 to a shell prompt at the end
of an install before the reboot or boot from the
install cd with 'linux rescue' and chroot to /mnt/sysinstall
after it mounts the drives for you.  Then:

grub
> device (hd0) /dev/sda
> root (hd0,0)
> setup (hd0)
> device (hd1) /dev/sdb
> root (hd1,0)
> setup (hd1)
> quit

If you are in rescue mode, exit twice to reboot. 

That assumes scsi disks and /boot as the first partition
of each of the 1st 2 drives.

-- 
  Les Mikesell
   lesmikesell at gmail.com