Re: Disk drive recovery help
On Wed, 08 Apr 2009 08:50:37 -0700, tony mollica posted:
> Thorny wrote:
>> On Wed, 08 Apr 2009 07:38:26 -0700, tony mollica posted:
>>
>>> Thorny wrote:
>>>> On Tue, 07 Apr 2009 15:29:16 -0700, tony mollica posted:
>>>>
>>>>> Hello.
>>>>>
>>>>> Need a little help with a disk drive.
>>>>>
>>>>> Until today, my external storage drive was working fine using Debian
>>>>> 4.0 (latest updates)
>>>>> and ext2 file system. It's a 180Gig drive divided into 3 partitions,
>>>>> 1 primary and 2 logical,
>>>>> sdg1, sdg5 and sdg6, for example.
>>>>>
>>>>> I did two things, after which the drive acts unusual. It powers up
>>>>> but takes a few minutes,
>>>>> then automounts only the third partition(sdg6). I can mount the
>>>>> second partition
>>>>> manually(sdg5), but the first, and only, primary partiton(sdg1) isn't
>>>>> found.
>>>>>
>>>>> cfdisk shows all partitions normally. I can e2fsck 5 and 6, but not
>>>>> 1. dmesg shows a read error in the sector that partition 1 begins.
>>>>> Can't access sdg1 at all, tried several different disk programs to
>>>>> access the partition.
>>>>>
>>>>> Back to the two things. I tried to change the disk label,
>>>>> unsuccessfully,
>>>>> and there
>>>>> was a call to check the partition, so I unmounted it and e2fsck'd it.
>>>>> Now I can only
>>>>> get to 2 of the 3 partitions. Everything seems to be there, but it
>>>>> won't recognize
>>>>> the first and only primary partition. All the sector numbers seem to
>>>>> match using
>>>>> gpart, lde, cfdisk and fdisk.
>>>>>
>>>>> Looking for suggestions to find the error in the first partition.
>>>>>
>>>>>
>>>> Just to clear up a misconception, you have to have a primary partition
>>>> to hold the logical partitions. So, make sure we are talking about
>>>> things correctly. With fdisk do you see both primaries with one being
>>>> shown as extended (and containing the logical partitions)?
>>>>
>>>> With the partition you are having trouble with unmounted, do you get
>>>> an error message when you try to fsck it?
>>>>
>>>>
>>> Yes, the necessary partitions are there. fdisk, cfdisk and testdisk
>>> all show
>>> the right stuff. Partition 1 is the problem, the other 2 I can mount
>>> normally.
>>> If I fsck part1 I get the message that no sdg1 exists (the drive is an
>>> external
>>> USB that used to have sdg1, sdg5 and sdg6). Testdisk even finds all
>>> the files. I thinking that there is some sort of hardware read error
>>> that's keeping
>>> the OS from recognizing the partition for mounting. I'm running some
>>> tests on the drive but I'll post that short error message from fsck
>>> shortly.
>>>
>>>
>> Tony, I think you missed my point. In order for there to be three usable
>> partitions on your system there has to be a physical partition to hold
>> logical partitions 5 and 6, you must have two primary partitions.
>>
>> Post the output from fdisk -l.
>>
>>
> Thorny, I know what you're asking, I just wasn't clear. But yes, the
> partition
> is there (or here):
>
> fdisk -l output:
>
> Disk /dev/sdg: 184.4 GB, 184416067584 bytes 255 heads, 63 sectors/track,
> 22420 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes
>
> Device Boot Start End Blocks Id System
> /dev/sdg1 * 1 7295 58597056 83 Linux /dev/sdg2
> 7296 22420 121491562+ f W95 Ext'd (LBA) /dev/sdg5
> 7296 14590 58597056 83 Linux /dev/sdg6 14591
> 22420 62894443+ 83 Linux
>
>
> I'm having no problems with the extended partitions, only the first
> primary. All the number look good, just doesn't recognize sdg1 for
> mounting, or for fsck.
>
> # fsck /dev/sdg1
> fsck 1.40-WIP (14-Nov-2006)
> e2fsck 1.40-WIP (14-Nov-2006)
> fsck.ext2: No such file or directory while trying to open /dev/sdg1
>
> 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>
>
> All the partitioning software and disk utilities find the partitions. The
> first
> primary partition is not found or recognized. Tried backup superblocks
> too, but if it doesn't find the device, it won't find the data.
>
> All the data is there, I can see it with testdisk, I just can't retrieve
> or do
> anything with it.
>
> thanks,
>
Well, if fsck won't fix it and testdisk won't fix it (I had to look up
"testdisk" haven't used it myself) I don't have any further suggestions.
A professional drive recovery shop might be able to help but depending on
your data might not be cost effective.
I do note that you did not give the output of fdisk -l as I asked. You,
once again, edited the information you gave. I have no way of determining
that you are trying to work on the correct drive (how many drives total
in your system), you should probably make sure the drives are being
enumerated into device nodes as you think they are. Other than that, I
don't know what to suggest. If I think of anything later I will get back
to this thread.
Reply to: