Advice: Buy a new big disk and use rsync to make a copy of disks.
run it every night using cron.

Our insurance agent has us set him up with a back up on separate computer.
Theives broke into his office and took everyting.  If we hadn't put his old 
disks on the self - he would be out of business.

This is where it gets interesting.   If it is like SL5.6 you are done because 
you can't become root due to some problem in the code.   All you get is a 
couple of messages.   This was a problem I have had due to disk failures in 
the last year and on my wish list for 6.0. 

I really think this needs to be fixed.  

Every Unix and Linux system I have used in the last 30 years you were able to 
become root in a system error.   Even System V.  

If you are in a corner you can fix almost any problem but you need to be able 
to set user to root.

Good Luck

Larry Linder

On Wednesday 22 December 2010 2:42 pm, Pann McCuaig wrote:
> On Wed, Dec 22, 2010 at 13:00, Phong Nguyen wrote:
> > Have you tried determining what's in mdadm.conf in the initrd file? It
> > might be getting some incorrect assembly instructions for md0.
>
> This may well be the issue. Other than /etc/modprobe.conf (which is
> obvious from the mkinitrd man page) and /etc/mdadm.conf, what does the
> initrd file look at (or where can I find out)?
>
> > On 22 Dec 2010, at 1203, Pann McCuaig wrote:
> > > Greetings SL fans,
> > >
> > > Sorry for the length of this post, but I'm hoping someone can come to
> > > my rescue and want to provide sufficient context.
> > >
> > > Recently I had a hard drive failure on a Sun X4600 box running SL4.8.
> > > The box has four drives; the drive that failed was /boot (only). The
> > > other three drives make up /dev/md0.
> > >
> > > The /boot drive was not backed up (headsmack!).
> > >
> > > I have created a rescue USB stick based on the System Rescue CD, which
> > > boots via grub. I can boot the System Rescue CD successfully, and it
> > > sees /dev/md0, which I can then mount and read from and write to.
> > >
> > > I have attempted to create a kernel and initrd image to add to the USB
> > > stick that will boot the box as if the kernel and initrd image were on
> > > the failed (and now removed) boot drive.
> > >
> > > I built the kernel and initrd image on a box similar to the box with
> > > the failed hard drive. I replaced /etc/modprobe.conf with the file from
> > > the target server, and then did 'yum install kernel-largesmp'. I copied
> > > all the resulting kernel-related files from /boot to the USB stick, as
> > > well as the appropriate directory from /lib/modules.
> > >
> > > I then restored the helper box to its original state.
> > >
> > > I booted the System Rescue CD on the target system and copied the
> > > /lib/modules directory into place on /dev/md0. I fixed up grub/menu.lst
> > > to have a stanza to boot the newly created SL4 kernel. I rebooted the
> > > box, and everything seemed to be going swimmingly, until . . .
> > >
> > > . . . the booted kernel seems unable to build /dev/md0 and the boot
> > > process fails.
> > >
> > > In the original configuration, the boot drive was /dev/sda, and the
> > > drives making up the soft RAID partition were /dev/sdb, dev/sdc, and
> > > /dev/sdd.
> > >
> > > The System Rescue CD detects the USB stick as /dev/sda and the three
> > > SAS drives as sdb, sdc, and sdd. All is well.
> > >
> > > It's not clear to me what is going awry with the SL kernel, but as
> > > the boot verbiage scrolls by, I see /dev/sdc referenced twice, and no
> > > reference to /dev/sdd. When the kernel attempts to assemble /dev/md0,
> > > it uses /dev/sda, /dev/sdb, and /dev/sdc and this fails and /dev/md0
> > > cannot be mounted and the kernel panics.
> > >
> > > Help, please. Suggestions? Thanks.
> > >
> > > BTW, I've put both SL4.8 Disc One, and the SL4.8 Live CD on a bootable
> > > USB stick; both boot successfully, but I was unable to find a way to
> > > make either one recognize /dev/md0, much less "rescue" me.
> > >
> > > Cheers,
> > > Pann