bootable failed sw raid 1 with F9

[jrw]

Sander Hoentjen wrote:
> Hi list,
>
> For the first time in my life i tried to install Fedora with sw raid.
> See below what went wrong.
>
> Here is what I did:
> Start with 2 empty 500GB sata disks.
> Make sure nvraid is turned off in my BIOS.
> Start an F9 install, creating 2 sw RAID partitions: md0 and md1.
> md0 is 100MB and has an ext3 /boot.
> md1 has the rest of the space and is LVM.
> In the lvm I have created the rest of my partitions.
>
> Install went great, after reboot my system booted fine, so far so good.
> I then shutdown my system, pulled out a disk and started again. I got
> the message "GRUB Hard Disk Error". So I shut down, plugged the disk
> back in, pulled out the other one and started again. This time I was met
> by a GRUB shell, no boot logo, no idea what to do (no menu).
> Shutdown again, replug the disk, start again, get on IRC, type:
> grub
> root (hd0,0)
> setup (hd0)
> root (hd1,0)
> setup (hd1)
>
> After that: reboot minus 1 disk. I can see grub, with logo and boot
> options. It starts ok, i even get rhgb for a second and then I see:
> "fsck.ext3: Invalid argument while trying to open /dev/md0"
> I can go into a maintenance shell and when I do cat /proc/mdstat is see:
> md0 : inactive sda1[0](s)
>
> "mdadm --assemble /dev/md0" turns it active again, but well I have no
> idea how I can continue normal boot, if it is even possible.
>
> So this is my story, now my questions:
> - Did I do anything wrong? I performed the installation twice, with both
> times the same result.
> - Is this a bug somewhere? Do other people get the same or better
> results?
> - Is there anything I can do to fix this?
>
> Thanks for reading this far,
>
> Sander
>
>
>   
I have already experienced this problem and raised a report on Redhat 
bugzilla (no. 450722) although there  has been no response to it so far. 
I spent some time pinning the problem down to Fedora 9, (it is OK on 
Fedora 8 plus updates).

I have gone back to Fedora 8 for the particular machine I required Raid1 
for.

However, there a sort of work around.

Firstly, the machine boots if both discs are present. If the partitions 
on the failed disc are setfaulty, then the machine will reboot 
successfully with the failed disc removed, (providing you have 
originally 'grub'd' both discs).

I have persuaded myself that this is probably OK since the reason for 
rebooting with only one disc is when the other is already partly marked 
faulty.

I do consider it to be a serious fault since it hits you just when the 
reason for having Raid1 discs becomes justified when one fails.

Hope this helps

John Whitley