Ubuntu 12.10 64 bit seems not to recognize my external hard disk. It is a Vantec NST-310S3 external disk enclosure with a WD 3TB drive. The disk has two NTFS partitions. My PC is a dual boot system. Under Windows 7 the hard disk works fine but I can't make it work with Ubuntu. When the drive is connected to the PC then the command sudo fdisk -l seems to hang forever.

Below are the output of lsusb and cat /proc/partitions without the external drive and then with it connected. I added also the last lines of the dmesg command at the end.

First without the drive:

ilan@linux:~$ lsusb
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 13ba:0017 Unknown PS/2 Keyboard+Mouse Adapter
Bus 001 Device 004: ID 046d:c50e Logitech, Inc. Cordless Mouse Receiver
Bus 001 Device 005: ID 0ac8:3420 Z-Star Microelectronics Corp. Venus USB2.0 Camera
ilan@linux:~$ cat /proc/partitions 
major minor  #blocks  name
   8        0 1953514584 sda
   8        1     102400 sda1
   8        2  629043200 sda2
   8        3  367001600 sda3
   8        4          1 sda4
   8        5  471859200 sda5
   8        6  157286400 sda6
   8        7  324115456 sda7
   8        8    4101120 sda8
  11        0    1048575 sr0

Second with the USB 3 drive:

ilan@linux:~$ lsusb
Bus 001 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 002 Device 002: ID 8087:0024 Intel Corp. Integrated Rate Matching Hub
Bus 004 Device 002: ID 174c:55aa ASMedia Technology Inc. 
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 13ba:0017 Unknown PS/2 Keyboard+Mouse Adapter
Bus 001 Device 004: ID 046d:c50e Logitech, Inc. Cordless Mouse Receiver
Bus 001 Device 005: ID 0ac8:3420 Z-Star Microelectronics Corp. Venus USB2.0 Camera
ilan@linux:~$ cat /proc/partitions 
major minor  #blocks  name
   8        0 1953514584 sda
   8        1     102400 sda1
   8        2  629043200 sda2
   8        3  367001600 sda3
   8        4          1 sda4
   8        5  471859200 sda5
   8        6  157286400 sda6
   8        7  324115456 sda7
   8        8    4101120 sda8
  11        0    1048575 sr0
   8       16 2930266584 sdb
ilan@linux:~$ lsusb -v -s 004:002
Bus 004 Device 002: ID 174c:55aa ASMedia Technology Inc. 
Couldn't open device, some information will be missing
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               3.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0         9
  idVendor           0x174c ASMedia Technology Inc.
  idProduct          0x55aa 
  bcdDevice            1.00
  iManufacturer           2 
  iProduct                3 
  iSerial                 1 
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength           44
    bNumInterfaces          1
    bConfigurationValue     1
    iConfiguration          0 
    bmAttributes         0xc0
      Self Powered
    MaxPower                0mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           2
      bInterfaceClass         8 Mass Storage
      bInterfaceSubClass      6 SCSI
      bInterfaceProtocol     80 Bulk-Only
      iInterface              0 
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x81  EP 1 IN
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst              15
      Endpoint Descriptor:
        bLength                 7
        bDescriptorType         5
        bEndpointAddress     0x02  EP 2 OUT
        bmAttributes            2
          Transfer Type            Bulk
          Synch Type               None
          Usage Type               Data
        wMaxPacketSize     0x0400  1x 1024 bytes
        bInterval               0
        bMaxBurst              15
ilan@linux:~$ sudo fdisk -l
[sudo] password for ilan: 
Disk /dev/sda: 2000.4 GB, 2000398934016 bytes
255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0xf1b4f1ee
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *        2048      206847      102400    7  HPFS/NTFS/exFAT
/dev/sda2          206848  1258293247   629043200    7  HPFS/NTFS/exFAT
/dev/sda3      1258293248  1992296447   367001600    7  HPFS/NTFS/exFAT
/dev/sda4      1992298494  3907028991   957365249    f  W95 Ext'd (LBA)
/dev/sda5      1992298496  2936016895   471859200    7  HPFS/NTFS/exFAT
/dev/sda6      2936018944  3250591743   157286400    7  HPFS/NTFS/exFAT
/dev/sda7      3250593792  3898824703   324115456   83  Linux
/dev/sda8      3898826752  3907028991     4101120   82  Linux swap / Solaris

dmesg output after connecting the external drive:

[   23.740567] e1000e: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: Rx/Tx
[   23.740786] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
[   49.144673] usb 4-1: >new SuperSpeed USB device number 2 using xhci_hcd
[   49.163039] usb 4-1: >Parent hub missing LPM exit latency info.  Power management will be impacted.
[   49.166789] usb 4-1: >New USB device found, idVendor=174c, idProduct=55aa
[   49.166793] usb 4-1: >New USB device strings: Mfr=2, Product=3, SerialNumber=1
[   49.166796] usb 4-1: >Product: AS2105
[   49.166799] usb 4-1: >Manufacturer: ASMedia
[   49.166801] usb 4-1: >SerialNumber: 0123456789ABCDEF
[   49.206372] usbcore: registered new interface driver uas
[   49.228891] Initializing USB Mass Storage driver...
[   49.229042] scsi6 : usb-storage 4-1:1.0
[   49.229115] usbcore: registered new interface driver usb-storage
[   49.229116] USB Mass Storage support registered.
[   64.045528] scsi 6:0:0:0: >Direct-Access     WDC WD30 EZRX-00MMMB0     80.0 PQ: 0 ANSI: 0
[   64.046224] sd 6:0:0:0: >Attached scsi generic sg2 type 0
[   64.046881] sd 6:0:0:0: >[sdb] Very big device. Trying to use READ CAPACITY(16).
[   64.047610] sd 6:0:0:0: >[sdb] 5860533168 512-byte logical blocks: (3.00 TB/2.72 TiB)
[   64.048368] sd 6:0:0:0: >[sdb] Write Protect is off
[   64.048373] sd 6:0:0:0: >[sdb] Mode Sense: 23 00 00 00
[   64.048984] sd 6:0:0:0: >[sdb] No Caching mode page present
[   64.048987] sd 6:0:0:0: >[sdb] Assuming drive cache: write through
[   64.049297] sd 6:0:0:0: >[sdb] Very big device. Trying to use READ CAPACITY(16).
[   64.050942] sd 6:0:0:0: >[sdb] No Caching mode page present
[   64.050944] sd 6:0:0:0: >[sdb] Assuming drive cache: write through
[   94.245006] usb 4-1: >reset SuperSpeed USB device number 2 using xhci_hcd
[   94.262553] usb 4-1: >Parent hub missing LPM exit latency info.  Power management will be impacted.
[   94.263805] xhci_hcd 0000:03:00.0: >xHCI xhci_drop_endpoint called with disabled ep ffff8800d37d1c00
[   94.263808] xhci_hcd 0000:03:00.0: >xHCI xhci_drop_endpoint called with disabled ep ffff8800d37d1c40
[  125.262722] usb 4-1: >reset SuperSpeed USB device number 2 using xhci_hcd
[  125.280304] usb 4-1: >Parent hub missing LPM exit latency info.  Power management will be impacted.
[  125.281511] xhci_hcd 0000:03:00.0: >xHCI xhci_drop_endpoint called with disabled ep ffff8800d37d1c00
[  125.281516] xhci_hcd 0000:03:00.0: >xHCI xhci_drop_endpoint called with disabled ep ffff8800d37d1c40