Trouble booting a degraded RAID-1 array

I've been attempting to migrate my running server to RAID-1 using another hard drive identical to the current one. The general approach I've used is to create new drive to mirror the old one, set up the new drive as a degraded RAID-1 array using mdadm, rsync the contents of the old drive to the new drive, then add the old drive to the new RAID array when everything is working.

fdisk -l reports

Disk /dev/hda: 251.0 GB, 251000193024 bytes
255 heads, 63 sectors/track, 30515 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hda1   *           1          13      104391   fd  Linux raid autodetect
/dev/hda2              14       30515   245007315   8e  Linux LVM

#Disk /dev/hdb: 251.0 GB, 251000193024 bytes
255 heads, 63 sectors/track, 30515 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot      Start         End      Blocks   Id  System
/dev/hdb1   *           1          13      104391   fd  Linux raid autodetect
/dev/hdb2              14       30515   245007315   fd  Linux raid autodetect

The old disk is /dev/hda and as can be seen I've successfully migrated over the boot partition to run on a RAID device /dev/md1 (though I still boot off hda1 instead of md1).

On /dev/md0 I've created a logical group /dev/lvm-raid with two logical volumes, lvm0 (filesystem) and lvm1 (swap, yeah raid-0 would be better for this).

# lvscan
  ACTIVE            '/dev/VolGroup00/LogVol00' [232.12 GB] inherit
  ACTIVE            '/dev/VolGroup00/LogVol01' [1.50 GB] inherit
  ACTIVE            '/dev/lvm-raid/lvm0' [232.12 GB] inherit
  ACTIVE            '/dev/lvm-raid/lvm1' [1.50 GB] inherit
# pvdisplay /dev/md0
  --- Physical volume ---
  PV Name               /dev/md0
  VG Name               lvm-raid
  PV Size               233.66 GB / not usable 0
  Allocatable           yes
  PE Size (KByte)       4096
  Total PE              59816
  Free PE               9
  Allocated PE          59807
  PV UUID               9e8Ixn-xC4P-27qH-YrSP-KO8W-lfli-doMB34

But whenever I try to boot lvm0 using the following lines in grub

title Fedora Core raid (2.6.17-1.2174_FC5)
        root (hd0,0)
        kernel /vmlinuz-2.6.17-1.2174_FC5 ro root=/dev/lvm-raid/lvm0 rhgb quiet
quiet
        initrd /initrd-2.6.17-1.2174_FC5.img

I get the following error during boot

Reading all physical volumes. This may take a while...
Found volume group "VolGroup00" using metadata type lvm2
2 logical volume(s) in volume group "VolGroup00" now active
mount: count not find filesystem '/dev/root'
setuproot: moving /dev failed: No such file or directory
setuproot: error mounting /proc: No such file or directory
setuproot: error mounting /sys: No such file or directory
switchroot: mount failed: No such file or directory
Kernel panic - not syncing: Attempted to kill init!

It seems to me that it's not detecting the lvm-raid volume group at startup.

I've tried rebuilding the boot image with

mkinitrd -v --with=raid1 /boot/initrd-2.6.17-1.2174_FC5.img 2.6.17-1.2174_FC5

as well as setting /dev/lvm-raid/lvm0 to be / in /ect/fstab but it doesn't seem to make any difference.

Does anyone know how I can successfully boot /dev/lvm-raid/lvm0 ?

thanks

Reboot with a rescue CD then see if you can mount it manually.

After reboot type:

modprobe raid1
vgchange -a
mkdir /mnt/tmp
mount /dev/lvm-raid/lvm0 /mnt/tmp

Try mounting the other lv.

Do this with each drive.

Do it with RAID syncronized.

Thanks for the reply,

Originally Posted by ramram29 Reboot with a rescue CD then see if you can mount it manually. After reboot type: modprobe raid1

could not parse modules.dep (happened whenever I ran modprobe)

vgchange -a

# vgchange -ay
2 logical volume(s) in volume group "VolGroup00" now active

mkdir /mnt/tmp mount /dev/lvm-raid/lvm0 /mnt/tmp

/dev/lvm-raid didn't exist though I was successfully able to mount /dev/md1 (the boot partition), /dev/VolGroup00 existed and was able to mount fine (this was expected as the old disk still boots fine).

Just to let everyone know I've reposted the question at FedoraForum here

I'll update this thread as well if I find a solution.