Kernel Panic on boot related to software raid 6
 

I am relatively new to Linux and dont understand how the raid and LVM works the underlying distro is centos 4.X . The install setup did all the disk configuration. Some pointers on what the underlying issue is and where to look for help would be appreciated.

What happened
The Home Server appeared to stop responding. My teenage son (microsoft user!) rebooted the server (power off) mutiple times. Server now fails to boot fully.
Plugging in a monitor shows it is stopping with a Kernel panic.
server is setup as raid 6 not sure if hot spare was setup. bios shows all hdd present. 2 X IDE 300GB ea 4 x SATA 300GB ea.

While i could do a complete reinstall that would delete the data. I dont have a current back up so I would like to try to recover the data.


Screen lines just before panic -----
Raid6:device hda2 operational as raid disk 0
Raid6:device sdc2 operational as raid disk 4
Raid6:device sdb2 operational as raid disk 3
Raid6:device sda2 operational as raid disk 2
Raid6:device hdc2 operational as raid disk 1
Raid6:allocated 6285kb for md2
Raid6:raid level 6 set md2 active with 5 out of 6 devices, algorithm 2
RAID6 conf printout:
---rd:6 wd:5 fd:1
Disk 0, o:1, dev:hda2
Disk 1, o:1, dev:hdc2
Disk 2, o:1, dev:sda2
Disk 3, o:1, dev:sdb2
Disk 4, o:1, dev:sdc2
mdadm :/dev/md2 has been started with 5 drives (out of 6)
Making device-mapper control node
Scanning logical volumes
md:syncing RAID array md2
md:minimum _guaranteed_reconstruction speed :1000 KB/sec/disc.
md: using maximum available idle IO bandwith ….. for reconstruction
md:using 128k window over a total of 292929024 blocks
Reading all physical volumes. This may take a while...
cdrom : open failed
Found volume group "main" using metadata type lvm2
Activating logical volumes
2 logical volume(s) in volume group "main" now active
creating root device
Mounting root filesystem
EXT3-fs: journal inode is deleted
mount: error 22 mounting ext3
mount: error 2 mounting none
switching to new root
switchroot : mount failed : 22
Unmount /initrd/dev failed:2
Kernel panic - not syncing : Attempted to kill init!

It looks like you lost a hard drive, that is a hard drive has actually died and will need to be physically replaced... I could however be wrong. But that's just what it looks like to me, hopefully once replaced the software raid should be able to just rebuild itself and work. Again I could be wrong tho.