Rescue FC3T1

[Douglas Furlong]

Quoting "A. Kong" <ahwkong at ahwkong.com>:

> Hi, all,
> 
> I have install FC3T1 for a while and is quite happy about it. All of the 
> sudden the harddisk (/dev/hda) of /boot failed and the PC cannot be boot 
> up again.
> So, I replaced the harddisk, inrestalled FC3T1 and of course itthe PC 
> works again.
> 
> The problem is: in its previous 'life' , its mount is something like this:
> 
> /dev/hda1     /boot
> /dev/md0      /
> ...
> [snip]
> ...
> 
> That means I have used a RAID0 device to be mounted at '/'

I don't know how much you know about RAID and in particular RAID0. This is
actualy an oxymoron. RAID is meant to signafy "redundancy" this means you can
have 1 disk fail, and the "array" or "file system" just carries on working.

Unfortunately RAID0 does not do this, it combines two drives to give you one big
drive. The problem is, if any one drive fails, then you loose all of the data
(especially if you use raid0 striped).
 
> When I reinstalled the system, since only hda is broken and I want to be 
> able to see/use /dev/md0, I only choose to mount
> /dev/hda1 as /boot
> /dev/hda2 as /
> 
> My problem is How can I switched the '/' form /dev/hda2 back to /dev/md0?

You can re-create the md0 device however all of your data will be lost if your
hard drive breaks again. Is there any particular reason that you opted to use
RAID0? Do you need the speed/space? Can you not just have several file
systems/mount points and spread the space out a bit?

> What I have tried is to change the kernel parameters in 
> /boot/grub/grun.conf and changed
> root=LABEL=/        to
> root =/dev/md0
> 
> In this case, when the boot up sequence reaches SELinux it just fires up 
> tons of message. The swtich failed
> 
> Can anyone advise me how to switch '/' moun in this case? Is there a 
> better way to rescue it.

Unfortunately as mentioned before, I fear all of your data has been lost if
/dev/hda was part of the /dev/md0 RAID array...

Doug