[linux-lvm] Logical Volume on two disk, one is broken: how to restore data from the good disk?

[Marco Antonelli]

Hello,
I have one LV (/home/hom_vg/home_lv) spanning over two PV. The PVs
were created on /dev/hdc1 and /dev/hdd1, both covering the entire
disks hdc (120 gb) and hdd (200 gb) respectively.
The mapping is linear.

My hdc is physically damaged... I could not even run fsck, badblocks
and dd_rescue. All of them give an output like this (from dmesg):


hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=512, high=0,
low=512, sector=512
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 512
Buffer I/O error on device hdc, logical block 64
hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=512, high=0,
low=512, sector=512
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 512
Buffer I/O error on device hdc, logical block 64
Adding 690784k swap on /dev/hda4.  Priority:-1 extents:1 across:690784k
EXT3 FS on hda3, internal journal
hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=447, high=0,
low=447, sector=447
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 447
Buffer I/O error on device dm-0, logical block 0
hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=455, high=0,
low=455, sector=455
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 455
Buffer I/O error on device dm-0, logical block 1
hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=463, high=0,
low=463, sector=463
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 463
Buffer I/O error on device dm-0, logical block 2
hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=471, high=0,
low=471, sector=471
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 471
Buffer I/O error on device dm-0, logical block 3
hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=447, high=0,
low=447, sector=447
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 447
Buffer I/O error on device dm-0, logical block 0
fuse init (API version 7.8)
kjournald starting.  Commit interval 5 seconds
EXT3 FS on hda2, internal journal
EXT3-fs: mounted filesystem with ordered data mode.
hdc: dma_intr: status=0x51 { DriveReady SeekComplete Error }
hdc: dma_intr: error=0x40 { UncorrectableError }, LBAsect=449, high=0,
low=449, sector=449
ide: failed opcode was: unknown
end_request: I/O error, dev hdc, sector 449
EXT3-fs: unable to read superblock