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I have a 3TB Seagate Barracuda disk (model no. st3000dm001). The disk contains data and uses ext3. I am using an external SATA enclouser via USB. I am trying to mount the disk using my ubuntu machine.

When I use fdisk; it issues the following warning:

WARNING: GPT (GUID Partition Table) detected on '/dev/sdc'! The util sfdisk doesn't support GPT. Use GNU Parted.

When using Parted, it shows this line

/dev/sdc (3001GB)

which hardly indicates that the disk is recognised with the right size but when I look for further details; parted return the following:

Error: /dev/sdc: unrecognised disk label

I would be grateful if someone points me to other resources or show how would I mount this disk.


Thank you all for your comments. The disk contains over 2.5 TB of data and I don't really know how it was copied so not sure whether that was using an enclosure, duplicator docking station or other means.

Using the command: parted /dev/sdc

GNU Parted 2.2
Using /dev/sdc
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) P                                                                
Error: /dev/sdc: unrecognised disk label

Using the command: cat /proc/partitions

major minor  #blocks  name

  8   32   2930266584 sdc

It is only one partition.

Using the command: sudo mount /dev/sdc /mnt/data

mount: you must specify the filesystem type

I thought that mount detects the filesystem type automatically but then explicilty specified the filesystem type in the following command

sudo mount -t ext3 /dev/sdc /mnt/data

mount: wrong fs type, bad option, bad superblock on /dev/sdc,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

So, dmesg | tail

[36374.712557] usb 2-2: reset high speed USB device using ehci_hcd and address 2
[36374.991045] usb 2-2: reset high speed USB device using ehci_hcd and address 2
[36375.273782] usb 2-2: reset high speed USB device using ehci_hcd and address 2
[36375.552576] usb 2-2: reset high speed USB device using ehci_hcd and address 2
[36375.830083] usb 2-2: reset high speed USB device using ehci_hcd and address 2
[36375.984427] sd 25:0:0:0: [sdc] Unhandled error code
[36375.984430] sd 25:0:0:0: [sdc] Result: hostbyte=DID_ERROR driverbyte=DRIVER_OK
[36375.984434] sd 25:0:0:0: [sdc] CDB: Read(10): 28 00 00 00 00 02 00 00 02 00
[36375.984444] end_request: I/O error, dev sdc, sector 2
[36375.984459] EXT3-fs: unable to read superblock

I couldn't figure out what is happening! is there something to do with gpt?

Further analysis:

using the command: sudo gdisk -l /dev/sdc

GPT fdisk (gdisk) version 0.5.1

Partition table scan:
  MBR: not present
  BSD: not present
Caution: invalid main GPT header, but valid backup; regenerating main header
from backup!
Warning! One or more CRCs don't match. You should repair the disk!
  APM: not present
  GPT: damaged

Found invalid MBR and corrupt GPT. What do you want to do? (Using the
GPT MAY permit recovery of GPT data.)
 1 - GPT
 2 - Create blank GPT

Your answer:

I don't want to accidentally wipe the data :) so better be sure about what options to try.

share|improve this question
Please edit your question to show the exact command you used, and the full exact output. –  psusi May 8 '12 at 18:34
what does parted /dev/sdc print say? –  johnshen64 May 8 '12 at 18:45
Have you had it connected directly to SATA before, and now you want to connect using a USB enclosure? You seem to imply that there is data on the disk that you want to access. –  fstx May 8 '12 at 18:48

2 Answers 2

up vote 2 down vote accepted

So, I am answering my own question! might be useful for someone.

I connected the disk internally through SATA and it worked fine. It seems the problem is finding a proper enclouser which can work with such disks.

Thank you all for your help.

share|improve this answer

You will need to find out how partitions and filesystems were created on this disk. You can do so with the following:

cat /proc/partitions

If you don't see any sdc partitions, then it is possible that the ext3 is on the entire disk.

Try to mount it.

sudo mkdir /mnt/data
sudo mount /dev/sdc /mnt/data

if that fails, then try partitions such as /dev/sdc1 etc.

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