Raid5 trouble after Upgrade. How to change this magic number in superblock
Hello there,
I got a problem with my raid5.
After I updated my linux distribution the following happend:
While booting the autoraid process yells at me:
md: invalid raid superblock magic on md0
md: md0 has invalid sb, not importing
md: no nested devices found
md: autorun done
raid5: switching cache buffer size, 4096 --> 1024
cat /proc/mdstat looks completly ok
lsraid tells me that md0 doesnt have a valid superblock
mdadm --examine tells me that the magic number it reads from superblock /dev/md0 is not what was expected.
Strangely: The expected magic number is on the superblock of all four raid partitions!!!.
They all look like this:
/dev/hde1:
Magic : a92b4efc
Version : 00.90.00
UUID : 05527cce:757e81d8:7476d03f:5bfaaa2b Creation Time : Fri Jun 28 15:32:11 2002
Raid Level : raid5
Device Size : 97685632 (93.16 GiB 100.03 GB)
Raid Devices : 3
Total Devices : 4
Preferred Minor : 0
Update Time : Wed Apr 9 12:01:29 2003
State : dirty, no-errors
Active Devices : 3
Working Devices : 4
Failed Devices : 0
Spare Devices : 1
Checksum : 75f13011 - correct
Events : 0.147
Layout : left-symmetric
Chunk Size : 32K
Number Major Minor RaidDevice State
this 0 33 1 0 active sync /dev/hde1 0 0 33 1 0 active sync /dev/hde1 1 1 33 65 1 active sync /dev/hdf1 2 2 34 1 2 active sync /dev/hdg1 3 3 34 65 3 /dev/hdh1
All deviced show this info. But the md0 superblock seems to have a wrong magic number.
I can mount /dev/md0 just fine and also read or modify data. This error message is just making me nervous.
Can i change the superblock to the valid values again somehow? If yes how :)?
Any1 got an idea ?
Thx
Christian
P.S
Here my raidtab file
raiddev /dev/md0
raid-level 5 nr-raid-disks 3 nr-spare-disks 1
persistent-superblock 1
parity-algorithm left-symmetric
chunk-size 32
device /dev/hde1
raid-disk 0
device /dev/hdf1
raid-disk 1
device /dev/hdg1
raid-disk 2
device /dev/hdh1
spare-disk 0