# USB3.0 Ext HDD[SOLVED]

## jserink

Hi All:

I just got myself a Seagate 2T USB 3 drive for backups on my new laptop. Unfortunately, my Dell M4600 is finniky on boot and will not run clonezilla x64 at all so I wanted to just do a "dd" backup from the gentoo x64 live USB that I have, but I got confused when I plugged in my USB3 drive. I booted back into Linux on the machine and plugged the drive in, here is what I get:

jserinki7 linux # fdisk -l 

Disk /dev/sda: 500.1 GB, 500107862016 bytes

255 heads, 63 sectors/track, 60801 cylinders, total 976773168 sectors

Units = sectors of 1 * 512 = 512 bytes

Sector size (logical/physical): 512 bytes / 4096 bytes

I/O size (minimum/optimal): 4096 bytes / 4096 bytes

Disk identifier: 0xebe440c1

*

*

*

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1              63  3907024127  1953512032+   7  HPFS/NTFS/exFAT

Now hang on a minute, I redid the external drive as ext4. This is what the gentoo live USB showed as well.

Now look at this:

jserinki7 linux # fdisk /dev/sdb1

Command (m for help): p

Disk /dev/sdb1: 2000.4 GB, 2000396321280 bytes

255 heads, 63 sectors/track, 243201 cylinders, total 3907024065 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: 0x5c9ea4e5

     Device Boot      Start         End      Blocks   Id  System

/dev/sdb1p1   *        2048  3907024064  1953511008+  83  Linux

Command (m for help): 

WTF????

When I do fdisk -l it shows an NTFS/HPFS drive starting on block 63, when I go into fdisk it shows a Linux drive starting at block 2048.

Am I going mad here? Does anyone know what is going on?

Does this have something to so with the new 4096 cluster sizes for new disks?

cheers,

JohnLast edited by jserink on Thu Dec 15, 2011 6:19 am; edited 1 time in total

----------

## Aquous

 *jserink wrote:*   

> Now look at this:
> 
> jserinki7 linux # fdisk /dev/sdb1

 

There's your problem. /dev/sdb1 is a partition and by telling fdisk to look at it you're telling it to look for partitions inside that partition. For some strange reason, it actually finds one! (it lists a /dev/sdb1p1)

You most likely typoed somewhere when making your partitions. The fix:

1) delete all partitions and repartition your drive using fdisk /dev/sdb. This will only update the MBR of your drive.

2) it's pretty messed up to find a partition inside a partition and that nested partition's metadata probably overwrote some critical filesystem structures. So rebuild the filesystem using e.g.

```
mkfs.ext4 /dev/sdb1
```

----------

## jserink

Hi Aquos:

you were absolutely correct.

I wiped everything, redid it and now it says this:

jserinki7 linux # fdisk -l

*

*

*

Disk /dev/sdb: 2000.4 GB, 2000398933504 bytes

81 heads, 62 sectors/track, 777982 cylinders, total 3907029167 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: 0x51f4cf7e

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1            2048  3907029166  1953513559+  83  Linux

jserinki7 linux # fdisk /dev/sdb 

Command (m for help): p

Disk /dev/sdb: 2000.4 GB, 2000398933504 bytes

81 heads, 62 sectors/track, 777982 cylinders, total 3907029167 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: 0x51f4cf7e

   Device Boot      Start         End      Blocks   Id  System

/dev/sdb1            2048  3907029166  1953513559+  83  Linux

Ok, I'm good.

Cheers,

John

----------

