[gentoo-user] Re: USB drive dead? (Commands to check?)

[Mark Knecht <markknecht@gmail.com>]

On Sat, Sep 19, 2009 at 3:21 PM, Mark Knecht <markknecht@gmail.com> wrote:
> Hi,
>   I seem to have lost an external USB drive I've been using on my
> MythTV backend server for video storage. What commands can I try to
> get it to wake up or at least show me what's working and what isn't?
> The drive shows under fdisk /dev/sda. I can see the large partition,
> and it seems to be the right size, according to fdisk anyway, but I
> cannot mount it using mount, and so far I cannot get e2fsck to do
> anything. Both of these fail:
>
>
> mount -t ext2 /dev/sda1 /video
> mount -t ext3 /dev/sda1 /video
>
>   I have power cycled the drive and I've rebooted the MacMini. Nothing changed.
>
> Thanks in advance,
> Mark
>
> MacMini ~ # fdisk /dev/sda
>
> The number of cylinders for this disk is set to 19929.
> There is nothing wrong with that, but this is larger than 1024,
> and could in certain setups cause problems with:
> 1) software that runs at boot time (e.g., old versions of LILO)
> 2) booting and partitioning software from other OSs
>   (e.g., DOS FDISK, OS/2 FDISK)
>
> Command (m for help): p
>
> Disk /dev/sda: 163.9 GB, 163928604672 bytes
> 255 heads, 63 sectors/track, 19929 cylinders
> Units = cylinders of 16065 * 512 = 8225280 bytes
> Disk identifier: 0xa9b5c6b5
>
>   Device Boot      Start         End      Blocks   Id  System
> /dev/sda1               1       19929   160079661   83  Linux
>
> Command (m for help):
>
>
>
> MacMini ~ # df
> Filesystem           1K-blocks      Used Available Use% Mounted on
> /dev/hda4             75890040  37169416  34865560  52% /
> udev                     10240       156     10084   2% /dev
> shm                     257396         0    257396   0% /dev/shm
> MacMini ~ # fsck -t ext3 /dev/sda
> fsck 1.41.3 (12-Oct-2008)
> e2fsck 1.41.3 (12-Oct-2008)
> fsck.ext3: Superblock invalid, trying backup blocks...
> fsck.ext3: Bad magic number in super-block while trying to open /dev/sda
>
> The superblock could not be read or does not describe a correct ext2
> filesystem.  If the device is valid and it really contains an ext2
> filesystem (and not swap or ufs or something else), then the superblock
> is corrupt, and you might try running e2fsck with an alternate superblock:
>    e2fsck -b 8193 <device>
>
> MacMini ~ # e2fsck -b 8193 /dev/sda
> e2fsck 1.41.3 (12-Oct-2008)
> e2fsck: Bad magic number in super-block while trying to open /dev/sda
>
> The superblock could not be read or does not describe a correct ext2
> filesystem.  If the device is valid and it really contains an ext2
> filesystem (and not swap or ufs or something else), then the superblock
> is corrupt, and you might try running e2fsck with an alternate superblock:
>    e2fsck -b 8193 <device>
>
> MacMini ~ # fsck -t ext3 /dev/sda1
> fsck 1.41.3 (12-Oct-2008)
> e2fsck 1.41.3 (12-Oct-2008)
> fsck.ext3: Attempt to read block from filesystem resulted in short
> read while tr            ying to open /dev/sda1
> Could this be a zero-length partition?
> MacMini ~ # e2fsck -b 8193 /dev/sda1
> e2fsck 1.41.3 (12-Oct-2008)
> e2fsck: Bad magic number in super-block while trying to open /dev/sda1
>
> The superblock could not be read or does not describe a correct ext2
> filesystem.  If the device is valid and it really contains an ext2
> filesystem (and not swap or ufs or something else), then the superblock
> is corrupt, and you might try running e2fsck with an alternate superblock:
>    e2fsck -b 8193 <device>
>
> MacMini ~ # e2fsck -b 8193 /dev/sda
> e2fsck 1.41.3 (12-Oct-2008)
> e2fsck: Bad magic number in super-block while trying to open /dev/sda
>
> The superblock could not be read or does not describe a correct ext2
> filesystem.  If the device is valid and it really contains an ext2
> filesystem (and not swap or ufs or something else), then the superblock
> is corrupt, and you might try running e2fsck with an alternate superblock:
>    e2fsck -b 8193 <device>
>
> MacMini ~ #
>

A little more info:

Buffer I/O error on device sda, logical block 12
sd 0:0:0:0: [sda] Result: hostbyte=0x00 driverbyte=0x08
sd 0:0:0:0: [sda] Sense Key : 0x3 [current]
sd 0:0:0:0: [sda] ASC=0x4b ASCQ=0x0
end_request: I/O error, dev sda, sector 96
Buffer I/O error on device sda, logical block 12
sd 0:0:0:0: [sda] Result: hostbyte=0x00 driverbyte=0x08
sd 0:0:0:0: [sda] Sense Key : 0x3 [current]
sd 0:0:0:0: [sda] ASC=0x4b ASCQ=0x0
end_request: I/O error, dev sda, sector 96
Buffer I/O error on device sda, logical block 12
sd 0:0:0:0: [sda] Result: hostbyte=0x00 driverbyte=0x08
sd 0:0:0:0: [sda] Sense Key : 0x3 [current]
sd 0:0:0:0: [sda] ASC=0x4b ASCQ=0x0
end_request: I/O error, dev sda, sector 96

MacMini ~ # fsck -t ext3 /dev/sda1
fsck 1.41.3 (12-Oct-2008)
e2fsck 1.41.3 (12-Oct-2008)
fsck.ext3: Attempt to read block from filesystem resulted in short
read while trying to open /dev/sda1
Could this be a zero-length partition?
MacMini ~ #


end_request: I/O error, dev sda, sector 95
__ratelimit: 58 callbacks suppressed
Buffer I/O error on device sda1, logical block 16
Buffer I/O error on device sda1, logical block 17
Buffer I/O error on device sda1, logical block 18
Buffer I/O error on device sda1, logical block 19
Buffer I/O error on device sda1, logical block 20
Buffer I/O error on device sda1, logical block 21
Buffer I/O error on device sda1, logical block 22
Buffer I/O error on device sda1, logical block 23
Buffer I/O error on device sda1, logical block 24
Buffer I/O error on device sda1, logical block 25
sd 0:0:0:0: [sda] Result: hostbyte=0x00 driverbyte=0x08
sd 0:0:0:0: [sda] Sense Key : 0x3 [current]
sd 0:0:0:0: [sda] ASC=0x4b ASCQ=0x0
end_request: I/O error, dev sda, sector 95
__ratelimit: 86 callbacks suppressed
Buffer I/O error on device sda1, logical block 16
Buffer I/O error on device sda1, logical block 17
Buffer I/O error on device sda1, logical block 18
Buffer I/O error on device sda1, logical block 19
Buffer I/O error on device sda1, logical block 20
Buffer I/O error on device sda1, logical block 21
Buffer I/O error on device sda1, logical block 22
Buffer I/O error on device sda1, logical block 23
Buffer I/O error on device sda1, logical block 24
Buffer I/O error on device sda1, logical block 25
MacMini ~ #


I could try reinstalling the file system but I had a few backups on
this drive for other systems. (non-critical, but possibly useful) I'd
like to be sure I cannot recover them before I blow everything away.

Thanks,
Mark