Raid5 trouble after Upgrade. How to change this magic number in superblock

[Christian Feddern <rangerone@web.de>]

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

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