mounting GPT USB-Drive

[ornago]

With my main computer (Win7 PC) i collected many data and saved it on the external drive. It has a GPT format says Windows and two partitions 1.5TB for Media (in exfat) and 500GB for Backup (in NTFS). Now I want to have a NAS and set up an Ubuntu Server 64bit 12.04. It's working very fine.
But let's get back to my problem. I'm having some trouble mounting the external WD MyBook USB-Drive.

'fdisk -l' shows:


Warnung: GPT (GUID-Partitionstabelle) auf '/dev/sda' erkannt! Das Hilfsprogramm Fdisk unterstützt GPT nicht. Verwenden Sie GNU Parted.


Disk /dev/sda: 120.0 GB, 120034123776 bytes
255 Köpfe, 63 Sektoren/Spur, 14593 Zylinder, zusammen 234441648 Sektoren
Einheiten = Sektoren von 1 × 512 = 512 Bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Festplattenidentifikation: 0x00000000

Gerät boot. Anfang Ende Blöcke Id System
/dev/sda1 1 234441647 117220823+ ee GPT

Warnung: GPT (GUID-Partitionstabelle) auf '/dev/sdb' erkannt! Das Hilfsprogramm Fdisk unterstützt GPT nicht. Verwenden Sie GNU Parted.


Disk /dev/sdb: 2000.4 GB, 2000396746752 bytes
255 Köpfe, 63 Sektoren/Spur, 243201 Zylinder, zusammen 3907024896 Sektoren
Einheiten = Sektoren von 1 × 512 = 512 Bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Festplattenidentifikation: 0x0d6cceb9

Gerät boot. Anfang Ende Blöcke Id System
/dev/sdb1 1 409639 204819+ ee GPT
/dev/sdb2 411648 977233919 488411136 7 HPFS/NTFS/exFAT
/dev/sdb3 977235968 3907022847 1464893440 7 HPFS/NTFS/exFAT


So /dev/sdb is my external drive and has the partitions i talked about.

'gdisk -l' says:


GPT fdisk (gdisk) version 0.8.1

Problem opening -l for reading! Error is 2.
The specified file does not exist!


'gdisk /dev/sdb' shows:


PT fdisk (gdisk) version 0.8.1

Partition table scan:
MBR: hybrid
BSD: not present
APM: not present
GPT: present

Found valid GPT with hybrid MBR; using GPT.

Command (? for help): p
Disk /dev/sdb: 3907024896 sectors, 1.8 TiB
Logical sector size: 512 bytes
Disk identifier (GUID): 6A692D7C-1054-4AE4-A292-1C6E6DFDE611
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 3907024862
Partitions will be aligned on 8-sector boundaries
Total free space is 976828349 sectors (465.8 GiB)

Number Start (sector) End (sector) Size Code Name
1 40 409639 200.0 MiB EF00 EF
2 977235968 3907022847 1.4 TiB 0700 Da

Here partition #2 is /dev/sdb3 like in fdisk. But where is my Backup partition? I think it has something to do with the hybrid MBR?! What can I do to mount it? the exfat is now available through: http://apcmag.com/how-to-enable-exfat-in-ubuntu.htm

[oldfred]

That fdisk does not work with gpt drives is normal. And the error on the first entry of gdisk was just from formating the entry incorrectly.
The second worked just as it should but shows a 200MB efi boot partition and a 1.4TB data partition.

But it also says it is a hybrid which can be dangerous if you let them get out of sync. You only need hybrid when using a Mac and booting Windows which you cannot do with an external drive. How did it become a hybrid?

You can also use parted to list partitions on a gpt drive.

http://www.rodsbooks.com/gdisk/hybrid.html
http://www.microsoft.com/whdc/device/storage/GPT_FAQ.mspx