On Sat, Sep 19, 2009 at 3:21 PM, Mark Knecht <markkne...@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
