3TB HDD with XFS Filesystem shows partition size of only 2TB

Using TestDisk to repair the filesystem
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Posts: 5
Joined: 13 Jul 2013, 08:56

3TB HDD with XFS Filesystem shows partition size of only 2TB

#1 Post by cmonty »


I have a 3TB harddisk (WD30EZRX) that is filled up by 75% with data (ts-stream-files), but the harddisk is identified with only 2TB. This HDD is formatted with XFS.

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knoppix@Microknoppix:~$ sudo fdisk -l
Disk /dev/sda: 2000.4 GB, 2000421444608 bytes
255 heads, 63 sectors/track, 243204 cylinders, total 3907073134 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
Verifying the disk with gdisk shows 4 errors:

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Expert command (? for help): v

Caution: The CRC for the backup partition table is invalid. This table may
be corrupt. This program will automatically create a new backup partition
table when you save your partitions.

Problem: The secondary header's self-pointer indicates that it doesn't reside
at the end of the disk. If you've added a disk to a RAID array, use the 'e'
option on the experts' menu to adjust the secondary header's and partition
table's locations.

Problem: Disk is too small to hold all the data!
(Disk size is 3907073134 sectors, needs to be 5860533168 sectors.)
The 'e' option on the experts' menu may fix this problem.

Problem: partition 1 is too big for the disk.

Identified 4 problems!
My understanding of the issue is, that the partition table does not match to the physical disk size, and because there's more data stored on the disk than would fit in the 2TB partition, I cannot access the data anymore.

Why does this happen? Well, I assume the root cause is the mainboard "Gigabyte P35-DS4" that does support HDD with max. size 2.2TB.

Can I repairt the damaged partition table in order to access the files?
Or can I make a low-level copy of the data to a backup HDD (same type, same size 3TB) starting from first sector 2048 until the last readable sector?