Re: RAID 5 inaccessible - continued

[Krekna Mektek <krekna@gmail.com>]

Krekna is crying out loud in the empty wilderness....
No one there to help me?

Krekna

2006/2/13, Krekna Mektek <krekna@gmail.com>:
> All right, this weekend I was able to use dd to create an imagefile
> out of the disk.
> I did the folowing:
>
> dd conv=noerror if=dev/hdd1 of=/mnt/hdb1/Faulty-RAIDDisk.img
> losetup /dev/loop0 /mnt/hdb1/Faulty-RAIDDisk.img
>
> I edited the mdadm.conf, by replacing /dev/hdd1 for /dev/loop0.
>
> But it did not work out (yet).
>
> madm -E /dev/loop0
> mdadm: No super block found on /dev/loop0 (Expected magic a92b4efc,
> got 00000000)
>
>
> How can I continue best?
>
> - mdadm -A --force /dev/md0
>
> or
>
> - can I restore the superblock from the hdd1 disk (which is still alive)
>
> or
>
> - can I configure mdadm.conf other than this:
>  (/dev/hdc1 is spare, probably out of date)
>
> DEVICE /dev/hdb1 /dev/hdc1 /dev/loop0
> ARRAY /dev/md0 devices=/dev/hdb1,/dev/hdc1,/dev/loop0
>
> or
> - some other solution?
>
> Krekna
>
> 2006/2/8, Krekna Mektek <krekna@gmail.com>:
> > Hi,
> >
> > I found out that my storage drive was gone and I went to my server to
> > check out what wrong.
> > I've got 3 400GB disks wich form the array.
> >
> > I found out I had one spare and one faulty drive, and the RAID 5 array
> > was not able to recover.
> > After a reboot because of some stuff with Xen my main rootdisk (hda)
> > was also failing, and the whole machine was not able to boot anymore.
> > And there I was...
> > After I tried to commit suicide and did not succeed, I went back to my
> > server to try something out.
> > I booted with Knoppix 4.02 and edited the mdadm.conf as follows:
> >
> > DEVICE /dev/hd[bcd]1
> > ARRAY /dev/md0 devices=/dev/hdb1,/dev/hdc1,/dev/hdd1
> >
> >
> > I executed mdrun and the following messages appeared:
> >
> > Forcing event count in /dev/hdd1(2) from 81190986 upto 88231796
> > clearing FAULTY flag for device 2 in /dev/md0 for /dev/hdd1
> > /dev/md0 has been started with 2 drives (out of 3) and 1 spare.
> >
> > So I thought I was lucky enough, to get back my data, maybe a bit lost
> > concerning the event count which is missing some. Am I right?
> >
> > But, when I tried to mount it the next day, this was also not
> > happening. I ended up with one faulty, one spare and one active. After
> > stopping and starting the array sometimes the array was rebuilding
> > again. I found out that the disk that it needs to rebuilt the array
> > (hdd1 that is) is
> > getting errors and falls back to faulty again.
> >
> >
> >
> >     Number   Major   Minor   RaidDevice State
> >        0       3       65        0      active sync
> >        1       0        0        -      removed
> >        2      22       65        2      active sync
> >
> >        3      22        1        1      spare rebuilding
> >
> >
> > and then this:
> >
> > Rebuild Status : 1% complete
> >
> >     Number   Major   Minor   RaidDevice State
> >        0       3       65        0      active sync
> >        1       0        0        -      removed
> >        2       0        0        -      removed
> >
> >        3      22        1        1      spare rebuilding
> >        4      22       65        2      faulty
> >
> > And my dmesg is full of these errors coming from the faulty hdd:
> > end_request: I/O error, dev hdd, sector 13614775
> > hdd: dma_intr: status=0x51 { DriveReady SeekComplete Error }
> > hdd: dma_intr: error=0x40 { UncorrectableError }, LBAsect=13615063,
> > high=0, low=13615063, sector=13614783
> > ide: failed opcode was: unknown
> > end_request: I/O error, dev hdd, sector 13614783
> >
> >
> > I guess this will never succeed...
> >
> > Is there away to get this data back from the individual disks perhaps?
> >
> >
> > FYI:
> >
> >
> > root@6[~]# cat /proc/mdstat
> > Personalities : [raid5]
> > md0 : active raid5 hdb1[0] hdc1[3] hdd1[4](F)
> >       781417472 blocks level 5, 64k chunk, algorithm 2 [3/1] [U__]
> >       [>....................]  recovery =  1.7% (6807460/390708736)
> > finish=3626.9min speed=1764K/sec
> > unused devices: <none>
> >
> > Krekna
> >
>