On Tue, June 10, 2008 5:24 pm, Wayne Gemmell wrote:

Hi all

I run a 4 disk array with 6 RAID 1 partitions. This is a very simple
configurations which has served me well through multiple drive failures. I
now have a wierd problem. One of the disks has become a critical node. My
server does not boot without this disk no matter which disk is my primary
boot disk (bios). I've changed the order of the disks and it makes no
difference.

When this disk is not in booting from some of the other disks gives me a
warning that there is an invalid superblock magic on sda. They all end up
with an error on stdin and modprobe failing.


Any ideas how to resolve this? I'm leaning towards nukeing sd[acd] and
re-adding them.

I suggest you provide lots more details.
Probably
  mdadm -Dsv
and
  mdadm -Esv
would be a good start.

NeilBrown