[dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?
dpchrist at holgerdanske.com
Wed Apr 20 06:14:24 CEST 2016
On 04/19/2016 12:08 PM, Joe Hillenbrand wrote:
> I have a 12TB hardware RAID5 external hard drive array.
4 @ 4 TB HDD's? What is the make/ model of external hard drive array?
What is the make/ model of the drives? What is/ are the interface(s) to
> I had initially planned to only ever encrypt data to the device, but now I
> need about half encrypted and half not.
2 @ 4 TB => 4 TB RAID1 and 2 @ 4 TB => 4 TB RAID1 encrypted?
> The device is `/dev/sdd`. It mounts as `fatty`.
> There is no partition table.
> As you can see LUKS starts at the first byte of the device.
> There is a btrfs filesystem on the LUKS device and I resized it down to 4TB.
> I can't really move the data anywhere, because it's too big and would
> require buying more hardware.
> Is it possible to add a partition table without losing the data?
A few years back I tried to be a cowboy and rearrange my large data
without buying additional hardware. I lost data. I then bought enough
hardware to implement daily backups with dual redundant copies:
1. I like large desktop HDD's for backups. If you use 8 TB HDD's for
backups, 2 @ 4 TB RAID1's should fit onto one backup drive.
2. Mobile docks both protect the drives and make it easy to move the
drives around (e.g. off-site rotation):
I realize that's a big investment -- 420+ USD per drive plus rack. My 3
@ 3 TB drives with racks cost me ~800 USD. It was worth it.
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