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I had a disk die in my level 5 RAID and before I could replace it, my RAID crapped out while I was copying some data onto it.

Reading the RAID kernel wiki on RAID recovery I've tried forcing an assemble with no success:

# mdadm --assemble --force /dev/md1 /dev/sda1 /dev/sdc1
mdadm: /dev/md1 assembled from 1 drive - not enough to start the array.

The results from mdadm --examine are:

/dev/sda1:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x1
     Array UUID : 2f3274a9:e3975c44:43e0066f:3c4e819d
           Name : Jupiter:1
  Creation Time : Sun Aug 26 17:41:46 2012
     Raid Level : raid5
   Raid Devices : 3

 Avail Dev Size : 3907025072 (1863.01 GiB 2000.40 GB)
     Array Size : 3907023872 (3726.03 GiB 4000.79 GB)
  Used Dev Size : 3907023872 (1863.01 GiB 2000.40 GB)
    Data Offset : 2048 sectors
   Super Offset : 8 sectors
          State : clean
    Device UUID : 6c242f92:9b39c56a:c238964e:82ed1fdd

Internal Bitmap : 8 sectors from superblock
    Update Time : Sat Sep 21 11:20:47 2013
       Checksum : e38c9e3b - correct
         Events : 13880

         Layout : left-symmetric
     Chunk Size : 512K

   Device Role : Active device 1
   Array State : .A. ('A' == active, '.' == missing)

/dev/sdc1:
          Magic : a92b4efc
        Version : 1.2
    Feature Map : 0x3
     Array UUID : 2f3274a9:e3975c44:43e0066f:3c4e819d
           Name : Jupiter:1
  Creation Time : Sun Aug 26 17:41:46 2012
     Raid Level : raid5
   Raid Devices : 3

 Avail Dev Size : 3907025072 (1863.01 GiB 2000.40 GB)
     Array Size : 3907023872 (3726.03 GiB 4000.79 GB)
  Used Dev Size : 3907023872 (1863.01 GiB 2000.40 GB)
    Data Offset : 2048 sectors
   Super Offset : 8 sectors
Recovery Offset : 395033224 sectors
          State : clean
    Device UUID : 0aa93873:826723b0:5e73d226:dd8a8071

Internal Bitmap : 8 sectors from superblock
    Update Time : Mon Aug  5 05:11:05 2013
       Checksum : 8ddf93da - correct
         Events : 13298

         Layout : left-symmetric
     Chunk Size : 512K

   Device Role : Active device 0
   Array State : AAA ('A' == active, '.' == missing)

My initial thoughts from reading the wiki is that is because the Event count is so different mdadm can't reassemble the array.

I'm confused because I've been copying data over to the array successfully until now, so I don't know why the Event count would have drifted so far apart.

I desperately don't want to lose the data, but I need to obviously get the RAID going to then add a new third disk.

share|improve this question
    
mdadm --assemble --force /dev/md1 /dev/sda1 /dev/sdc1 you need a missing in there somewhere. Also, order matters. –  Zoredache Sep 21 '13 at 19:52
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