The 2TB disk that I use as an encrypted backup, is now reported by Ubuntu as being just free space. The encryption was setup as a LUKS encrypted device.
The output of sudo fdisk -l
reports:
Disk /dev/sdc: 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: 0x6b6edeba
Device Boot Start End Blocks Id System
Note that there is no partition information reported (there was only one partition on the disk).
Trying to open the disk with sudo cryptsetup luksOpen /dev/sdc crypt1
returns the error:
Device /dev/sdc is not a valid LUKS device.
Now luckily I have backups of the backup, so I can live with the data being going this time, however I need to know: What caused it and/or how I can fix it, because otherwise I can't trust my backup to be there in the future and I will have to find a different solution.
Edit1: Per request a screenshot of the Disks Utility:
This is on Ubuntu 14.04.3 LTS
.
testdisk /debug /log /dev/sdc
sudo head -c 4M /dev/sdc | xz > 4M.img.xz
somewhere? This will dump and compress the first 4 MiB of the drive into a file named4M.img.xz
, which might have some clues about what happened. In the future, I suggest making sure that the drive is partitioned with MBR or GPT. It is possible and common to create a LUKS volume out of the raw drive (without any partitioning), and many tools cannot recognize LUKS volumes, leading them to conclude falsely that the drive can be overwritten without harm. I suspect that is what happened here.