RAID 1 cannot boot (using grub)

RAID 1 cannot boot (using grub)

[Derek Yeung]

Hello everyone,

I would very much appreciate insight onto this problem:

System: IBM xSeries 335 / IDE Mirroring / RedHat 8 / Grub

I'm working on setting up mirroring on 2 IDE disks in RedHat 8.  I 
followed  Neil Brown's email to Stephen Lee (dated 20 Apr 2002).  

I created a degraded RAID 1 using /dev/hdc1, created a filesystem on 
it, copied everything from the existing boot to the new md device, 
modified the fstab accordingly.  Without the primary device added to 
the md set (meaning still working in degraded mode), the machine boots 
(with a few hitches -- something about a bad superblock and ext3 
mounting, which i will post more detail later)  -- but, it boots.  
The problem is after I add the /boot partition to the md set (i.e.: add 
hda1 to md1, which md1 already has hdc1), and then reboot, the machine 
fails to boot.  It stops after printing "GRUB".  Does anyone have any idea 
why?  

I'd very much appreciate any ideas/solutions.  

Thank you very, very much

/dky

Re: RAID 1 cannot boot (using grub)

[Alfred Isele]

Hello!
Maybe you forgot to setup grub anew on hda: 
After adding /dev/hda1 to /dev/md1 (/boot)
you have to setup grub for hda1 again, because
the boot files to be anchored within the MBR are now
located at positions different from /dev/sda1.
To save your system try this:
Boot from CDROM, 
wait for /dev/md1 to be mirrored
and stup grub for /dev/hda (i.e. the first disk):  

mount /dev/md1 /boot
grub
root (hd0,0)
setup (hd0)
quit

and reboot from disk 1.
Regards
Alfred


At 15:52 13.06.03 -0400, Derek Yeung wrote:
>
>Hello everyone,
>
>I would very much appreciate insight onto this problem:
>
>System: IBM xSeries 335 / IDE Mirroring / RedHat 8 / Grub
>
>I'm working on setting up mirroring on 2 IDE disks in RedHat 8.  I 
>followed  Neil Brown's email to Stephen Lee (dated 20 Apr 2002).  
>
>I created a degraded RAID 1 using /dev/hdc1, created a filesystem on 
>it, copied everything from the existing boot to the new md device, 
>modified the fstab accordingly.  Without the primary device added to 
>the md set (meaning still working in degraded mode), the machine boots 
>(with a few hitches -- something about a bad superblock and ext3 
>mounting, which i will post more detail later)  -- but, it boots.  
>The problem is after I add the /boot partition to the md set (i.e.: add 
>hda1 to md1, which md1 already has hdc1), and then reboot, the machine 
>fails to boot.  It stops after printing "GRUB".  Does anyone have any idea 
>why?  
>
>I'd very much appreciate any ideas/solutions.  
>
>Thank you very, very much
>
>/dky
>
>
>-
>To unsubscribe from this list: send the line "unsubscribe linux-raid" in
>the body of a message to majordomo@vger.kernel.org
>More majordomo info at  http://vger.kernel.org/majordomo-info.html
>

Re: RAID 1 cannot boot (using grub)

[Steven Dake]

Derek,

Lilo supports booting to RAID 1 volumes, and I know it has worked since 
I've tested it.

As for GRUB, I've never managed to get it to work, but I have not tried 
with a new grub for 9 months atlesat.

So the recomendation is to try lilo.

Good luck
-steve

Derek Yeung wrote:

>Hello everyone,
>
>I would very much appreciate insight onto this problem:
>
>System: IBM xSeries 335 / IDE Mirroring / RedHat 8 / Grub
>
>I'm working on setting up mirroring on 2 IDE disks in RedHat 8.  I 
>followed  Neil Brown's email to Stephen Lee (dated 20 Apr 2002).  
>
>I created a degraded RAID 1 using /dev/hdc1, created a filesystem on 
>it, copied everything from the existing boot to the new md device, 
>modified the fstab accordingly.  Without the primary device added to 
>the md set (meaning still working in degraded mode), the machine boots 
>(with a few hitches -- something about a bad superblock and ext3 
>mounting, which i will post more detail later)  -- but, it boots.  
>The problem is after I add the /boot partition to the md set (i.e.: add 
>hda1 to md1, which md1 already has hdc1), and then reboot, the machine 
>fails to boot.  It stops after printing "GRUB".  Does anyone have any idea 
>why?  
>
>I'd very much appreciate any ideas/solutions.  
>
>Thank you very, very much
>
>/dky
>
>
>-
>To unsubscribe from this list: send the line "unsubscribe linux-raid" in
>the body of a message to majordomo@vger.kernel.org
>More majordomo info at  http://vger.kernel.org/majordomo-info.html
>
>
>
>  
>

Re: RAID 1 cannot boot (using grub)

[Ricky Beam]

On Fri, 13 Jun 2003, Derek Yeung wrote:
>modified the fstab accordingly.  Without the primary device added to
>the md set (meaning still working in degraded mode), the machine boots
>(with a few hitches -- something about a bad superblock and ext3
>mounting, which i will post more detail later)  -- but, it boots.
>The problem is after I add the /boot partition to the md set (i.e.: add
>hda1 to md1, which md1 already has hdc1), and then reboot, the machine
>fails to boot.  It stops after printing "GRUB".  Does anyone have any idea
>why?

Simple.  You've destroyed part of the bootloader.  In this case, you
didn't wait for the mirroring to complete, did you?  If so, hda1, or
(hd0,0) to grub, does not contain a valid filesystem.  Thus, there is
no stage2 or grub.conf.

You'll have to install grub on both hda and hdc as the stage1 and stage1.5
are outside partitions being mirrored (MBR and the space following it.)  And
you have go out of your way to do it so it'll work if one of the drives dies.

--Ricky