Help! Raid-5 with 4 drives, one bad and one wants to be a spare

Ed K. ed at hp.uab.edu
Thu Sep 22 17:46:57 UTC 2005


I had a computer running FC1 for a very long while. All 4 ide drives are a 
part of a Raid-5 array.

Then a drive (#4) crapped out, and took down the other drive (#3) on the 
same ide bus... I would like to turn the raid back on, but when I do the 
raid subsystem thinks its spare.

Q: How can I turn the raid back on in degraded mode without the #3 drive 
being used as a spare?

...waiting for some pointers so I can sleep tonight, so any help would be 
most appreciated.

ed

p.s.:
I've booted the system in knoppix v3.9 now...

here are the commands:

root at 1[~]# mdadm --assemble /dev/md2 -R /dev/hda4 /dev/hdb4 /dev/hdc1
mdadm: failed to RUN_ARRAY /dev/md2: Invalid argument
root at 1[~]# mdadm -D /dev/md2
/dev/md2:
         Version : 00.90.01
   Creation Time : Mon Feb 23 21:13:37 2004
      Raid Level : raid5
     Device Size : 117185984 (111.76 GiB 120.00 GB)
    Raid Devices : 4
   Total Devices : 3
Preferred Minor : 2
     Persistence : Superblock is persistent

     Update Time : Thu Sep 22 14:07:32 2005
           State : active, degraded
  Active Devices : 2
Working Devices : 3
  Failed Devices : 0
   Spare Devices : 1

          Layout : left-asymmetric
      Chunk Size : 64K

     Number   Major   Minor   RaidDevice State
        0       3        4        0      active sync
        1       3       68        1      active sync
        2       0        0        -      removed
        3       0        0        -      removed

        4      22        1        -      spare
root at 1[~]# mdadm -S /dev/md2




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