# have I lost my data for ever?



## micromike (Oct 11, 2008)

Hello 
I hope someone can help me?

I have external harddrive which gives error:

[email protected]:~$ dmesg | tail
[32235.034502] sd 12:0:0:0: [sdb] Sense Key : Medium Error [current] 
[32235.034511] sd 12:0:0:0: [sdb] Add. Sense: Unrecovered read error
[32235.034521] end_request: I/O error, dev sdb, sector 0
[32235.034529] Buffer I/O error on device sdb, logical block 0
[32238.663588] sd 12:0:0:0: [sdb] Unhandled sense code
[32238.663597] sd 12:0:0:0: [sdb] Result: hostbyte=DID_OK driverbyte=DRIVER_SENSE
[32238.663604] sd 12:0:0:0: [sdb] Sense Key : Medium Error [current] 
[32238.663614] sd 12:0:0:0: [sdb] Add. Sense: Unrecovered read error
[32238.663624] end_request: I/O error, dev sdb, sector 0
[32238.663633] Buffer I/O error on device sdb, logical block 0

I cannot mount it or even find it via fdisk.

[email protected]:~$ sudo sfdisk -l /dev/sdb

Disk /dev/sdb: 238475 cylinders, 64 heads, 32 sectors/track
read: Input/output error

sfdisk: read error on /dev/sdb - cannot read sector 0
/dev/sdb: unrecognized partition table type
No partitions found

[email protected]:~$ sudo sfdisk /dev/sdb
Checking that no-one is using this disk right now ...
BLKRRPART: Input/output error
OK

Disk /dev/sdb: 238475 cylinders, 64 heads, 32 sectors/track
read: Input/output error

sfdisk: read error on /dev/sdb - cannot read sector 0
/dev/sdb: unrecognized partition table type
Old situation:
No partitions found
Input in the following format; absent fields get a default value.
<start> <size> <type [E,S,L,X,hex]> <bootable [-,*]> <c,h,s> <c,h,s>
Usually you only need to specify <start> and <size> (and perhaps <type>).

/dev/sdb1 :
/dev/sdb1 0+ 30400 30401- 244196032 83 Linux
/dev/sdb2 :
/dev/sdb2 0 - 0 0 0 Empty
/dev/sdb3 :
/dev/sdb3 0 - 0 0 0 Empty
/dev/sdb4 :
/dev/sdb4 0 - 0 0 0 Empty
New situation:
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/sdb1 0+ 30400 30401- 244196032 83 Linux
/dev/sdb2 0 - 0 0 0 Empty
/dev/sdb3 0 - 0 0 0 Empty
/dev/sdb4 0 - 0 0 0 Empty
Warning: no primary partition is marked bootable (active)
This does not matter for LILO, but the DOS MBR will not boot this disk.
Do you want to write this to disk? [ynq] y
Successfully wrote the new partition table

Re-reading the partition table ...

If you created or changed a DOS partition, /dev/foo7, say, then use dd(1)
to zero the first 512 bytes: dd if=/dev/zero of=/dev/foo7 bs=512 count=1
(See fdisk(8).)
[email protected]:~$ sudo sfdisk -l /dev/sdb

Disk /dev/sdb: 30401 cylinders, 255 heads, 63 sectors/track
Units = cylinders of 8225280 bytes, blocks of 1024 bytes, counting from 0

Device Boot Start End #cyls #blocks Id System
/dev/sdb1 0+ 30400 30401- 244196032 83 Linux
/dev/sdb2 0 - 0 0 0 Empty
/dev/sdb3 0 - 0 0 0 Empty
/dev/sdb4 0 - 0 0 0 Empty

[email protected]:~$ dd if=/dev/zero of=/dev/sdb bs=512 count=1
dd: opening `/dev/sdb': Permission denied
[email protected]:~$ sudo dd if=/dev/zero of=/dev/sdb bs=512 count=1
1+0 records in
1+0 records out
512 bytes (512 B) copied, 0.00438387 s, 117 kB/s

[email protected]:~$ sudo fdisk -l /dev/sdb

Disk /dev/sdb: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00000000

Disk /dev/sdb doesn't contain a valid partition table
[email protected]:~$ fdisk -l /dev/sdb
Cannot open /dev/sdb
[email protected]:~$ sudo fdisk -l /dev/sdb

Disk /dev/sdb: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x00000000

Disk /dev/sdb doesn't contain a valid partition table
[email protected]:~$ sudo sfdisk -l /dev/sdb

Disk /dev/sdb: 30401 cylinders, 255 heads, 63 sectors/track

sfdisk: ERROR: sector 0 does not have an msdos signature
/dev/sdb: unrecognized partition table type
No partitions found


What NOW???? :4-dontkno :upset: :upset:
have I lost my data for ever? 



thanks Mika.


----------



## djaburg (May 15, 2008)

I'm certainly no data recovery expert, but it doesn't sound too good. I'll ask the obvious, do you have any backups of your data?


----------



## micromike (Oct 11, 2008)

djaburg said:


> I'm certainly no data recovery expert, but it doesn't sound too good. I'll ask the obvious, do you have any backups of your data?


NOP, thats why I was asking. 

... Mika.


----------



## Corday (Mar 3, 2010)

There are third party paid apps that could possibly help for NTFS and FAT when partition was erased or ????. We can't recommend a particular one.


----------



## Old Rich (May 31, 2007)

Would you like me to move this to the hard drive forum where our wizard can help with data recovery?


----------



## hal8000 (Dec 23, 2006)

I dont suppose you have a copy of your partition table?
I always print off fdisk -l and copy start and end cylinders of every partition.

In your case, the partition table cannot be read which is bad news. However there
is testdisk (available on Ubuntu CD and other linux CD's in live mode) that may be able
to help with partition table recovery.

First thing you can check is physically look at the hard disk its geometry will be on a label with the CHS settings for the drive. If testdisk cannot figure out the partition table
you may be able to manually supply it, if it (was) a single partition then it may use all available cylinders.

You dont say which file system you used. Test disk is not limited to NTFS and recognises many file systems so could be your best hope, a step by step is on the link below:

TestDisk Step By Step - CGSecurity


----------

