[dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Joe Hillenbrand]

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I posted this to https://gitlab.com/cryptsetup/cryptsetup/issues/292
but now I'm worried that might not be the appropriate place to ask
questions.

I have a 12TB hardware RAID5 external hard drive array.

I had initially planned to only ever encrypt data to the device, but now I
need about half encrypted and half not.

The device is `/dev/sdd`. It mounts as `fatty`.

There is no partition table.

    # dd if=/dev/sdd | hexdump -C | head -1
    00000000  4c 55 4b 53 ba be 00 01  61 65 73 00 00 00 00 00
|LUKS....aes.....|

    # parted /dev/sdd
    GNU Parted 3.2
    Using /dev/sdd
    Welcome to GNU Parted! Type 'help' to view a list of commands.
    (parted) print

    Error: /dev/sdd: unrecognised disk label
    Model: ORICO H/ W RAID5 (scsi)

    Disk /dev/sdd: 12.0TB
    Sector size (logical/physical): 512B/4096B
    Partition Table: unknown
    Disk Flags:

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.

    # cryptsetup status fatty
    /dev/mapper/fatty is active.
      type:    LUKS1
      cipher:  aes-xts-plain64
      keysize: 256 bits
      device:  /dev/sdd
      offset:  4096 sectors
      size:    23441764352 sectors
      mode:    read/write

    # btrfs filesystem show /dev/mapper/fatty
    Label: 'fatty'  uuid: XXX-XX-XX-XX-XXXXXXXXX
        Total devices 1 FS bytes used 2.75TiB
        devid    1 size 4.00TiB used 2.80TiB path /dev/mapper/fatty

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?

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Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Arno Wagner]

First,

please do not post HTML email to the list. 

Second, while it is possible to add a partition table
without backup, it is an extremely dangerous operation, 
dangerous enough that your chances of doing so successfully 
are near zero if you have to ask how to do it. I strongly
recommend against trying. 

Now, if you want to lose all data, here is what you can try:
1. Resize filesystem in LUKS container to half device size.
2. Move LUKS container to end
3. Create partition table and a partition that covers 1st half 
   of the device. Create LUKS container and in it a 
   filesystem in that partition.
4. Mount LUKS container in 2nd half of disk (using offset)
   and LUKS conteiner in partition. 
5. Copy all data from filesystem in LUKS container in 2nd half 
   of disk to filesystem in LUKS conteiner in 1st half.
6. Unmap container in 2nd half of disk.
7. Create 2nd partition covering 2nd half of disk and
   put filesystem in there.

If you make one tiny mistake anywhere, chances are your 
data is gone. Do not try this without full, current backup.

Regards,
Arno


On Tue, Apr 19, 2016 at 21:08:37 CEST, Joe Hillenbrand wrote:
>    I posted this to [1]https://gitlab.com/cryptsetup/cryptsetup/issues/292
>    but now I'm worried that might not be the appropriate place to ask
>    questions.
>    I have a 12TB hardware RAID5 external hard drive array.
>    I had initially planned to only ever encrypt data to the device, but
>    now I need about half encrypted and half not.
>    The device is `/dev/sdd`. It mounts as `fatty`.
>    There is no partition table.
>    Â Â Â  # dd if=/dev/sdd | hexdump -C | head -1
>    Â Â Â  00000000Â  4c 55 4b 53 ba be 00 01Â  61 65 73 00 00 00 00 00Â
>    |LUKS....aes.....|
>    Â Â Â  # parted /dev/sdd
>    Â Â Â  GNU Parted 3.2
>    Â Â Â  Using /dev/sdd
>    Â Â Â  Welcome to GNU Parted! Type 'help' to view a list of commands.
>    Â Â Â  (parted)
>    print                                Â
>    Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  Â
>    Â Â Â  Error: /dev/sdd: unrecognised disk label
>    Â Â Â  Model: ORICO H/ W RAID5
>    (scsi)Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
>     Â Â Â Â Â Â Â Â  Â
>    Â Â Â  Disk /dev/sdd: 12.0TB
>    Â Â Â  Sector size (logical/physical): 512B/4096B
>    Â Â Â  Partition Table: unknown
>    Â Â Â  Disk Flags:
>    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.
>    Â Â Â  # cryptsetup status fatty
>    Â Â Â  /dev/mapper/fatty is active.
>    Â Â Â Â Â  type:Â Â Â  LUKS1
>    Â Â Â Â Â  cipher:Â  aes-xts-plain64
>    Â Â Â Â Â  keysize: 256 bits
>    Â Â Â Â Â  device:Â  /dev/sdd
>    Â Â Â Â Â  offset:Â  4096 sectors
>    Â Â Â Â Â  size:Â Â Â  23441764352 sectors
>    Â Â Â Â Â  mode:Â Â Â  read/write
>    Â Â Â  # btrfs filesystem show /dev/mapper/fatty
>    Â Â Â  Label: 'fatty'Â  uuid: XXX-XX-XX-XX-XXXXXXXXX
>    Â Â Â Â Â Â Â  Total devices 1 FS bytes used 2.75TiB
>            devid    1 size 4.00TiB used 2.80TiB path
>    /dev/mapper/fatty
>    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?
> 
> References
> 
>    1. https://gitlab.com/cryptsetup/cryptsetup/issues/292

> _______________________________________________
> dm-crypt mailing list
> dm-crypt@saout.de
> http://www.saout.de/mailman/listinfo/dm-crypt


-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
----
A good decision is based on knowledge and not on numbers. -- Plato

If it's in the news, don't worry about it.  The very definition of 
"news" is "something that hardly ever happens." -- Bruce Schneier

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Ralf Ramsauer]

Hi,

On 04/19/2016 10:06 PM, Arno Wagner wrote:
> First,
>
> please do not post HTML email to the list. 
>
> Second, while it is possible to add a partition table
> without backup, it is an extremely dangerous operation, 
> dangerous enough that your chances of doing so successfully 
> are near zero if you have to ask how to do it. I strongly
> recommend against trying. 
>
> Now, if you want to lose all data, here is what you can try:
> 1. Resize filesystem in LUKS container to half device size.
Joe has 2.8/4 TiB in use. I think it only works in-situ which is at
least as double as dangerous as your approach :-)
> 2. Move LUKS container to end
> 3. Create partition table and a partition that covers 1st half 
>    of the device. Create LUKS container and in it a 
>    filesystem in that partition.
> 4. Mount LUKS container in 2nd half of disk (using offset)
>    and LUKS conteiner in partition. 
> 5. Copy all data from filesystem in LUKS container in 2nd half 
>    of disk to filesystem in LUKS conteiner in 1st half.
> 6. Unmap container in 2nd half of disk.
> 7. Create 2nd partition covering 2nd half of disk and
>    put filesystem in there.
I second, this sounds a bit safer than my idea. Maybe it is possible to
backup 800GiB of data to follow Arnos solution.

  Ralf
>
> If you make one tiny mistake anywhere, chances are your 
> data is gone. Do not try this without full, current backup.
>
> Regards,
> Arno
>
>
> On Tue, Apr 19, 2016 at 21:08:37 CEST, Joe Hillenbrand wrote:
>>    I posted this to [1]https://gitlab.com/cryptsetup/cryptsetup/issues/292
>>    but now I'm worried that might not be the appropriate place to ask
>>    questions.
>>    I have a 12TB hardware RAID5 external hard drive array.
>>    I had initially planned to only ever encrypt data to the device, but
>>    now I need about half encrypted and half not.
>>    The device is `/dev/sdd`. It mounts as `fatty`.
>>    There is no partition table.
>>    Â Â Â  # dd if=/dev/sdd | hexdump -C | head -1
>>    Â Â Â  00000000Â  4c 55 4b 53 ba be 00 01Â  61 65 73 00 00 00 00 00Â
>>    |LUKS....aes.....|
>>    Â Â Â  # parted /dev/sdd
>>    Â Â Â  GNU Parted 3.2
>>    Â Â Â  Using /dev/sdd
>>    Â Â Â  Welcome to GNU Parted! Type 'help' to view a list of commands.
>>    Â Â Â  (parted)
>>    print                                Â
>>    Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â  Â
>>    Â Â Â  Error: /dev/sdd: unrecognised disk label
>>    Â Â Â  Model: ORICO H/ W RAID5
>>    (scsi)Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â
>>     Â Â Â Â Â Â Â Â  Â
>>    Â Â Â  Disk /dev/sdd: 12.0TB
>>    Â Â Â  Sector size (logical/physical): 512B/4096B
>>    Â Â Â  Partition Table: unknown
>>    Â Â Â  Disk Flags:
>>    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.
>>    Â Â Â  # cryptsetup status fatty
>>    Â Â Â  /dev/mapper/fatty is active.
>>    Â Â Â Â Â  type:Â Â Â  LUKS1
>>    Â Â Â Â Â  cipher:Â  aes-xts-plain64
>>    Â Â Â Â Â  keysize: 256 bits
>>    Â Â Â Â Â  device:Â  /dev/sdd
>>    Â Â Â Â Â  offset:Â  4096 sectors
>>    Â Â Â Â Â  size:Â Â Â  23441764352 sectors
>>    Â Â Â Â Â  mode:Â Â Â  read/write
>>    Â Â Â  # btrfs filesystem show /dev/mapper/fatty
>>    Â Â Â  Label: 'fatty'Â  uuid: XXX-XX-XX-XX-XXXXXXXXX
>>    Â Â Â Â Â Â Â  Total devices 1 FS bytes used 2.75TiB
>>            devid    1 size 4.00TiB used 2.80TiB path
>>    /dev/mapper/fatty
>>    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?
>>
>> References
>>
>>    1. https://gitlab.com/cryptsetup/cryptsetup/issues/292
>> _______________________________________________
>> dm-crypt mailing list
>> dm-crypt@saout.de
>> http://www.saout.de/mailman/listinfo/dm-crypt
>

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Michael Kjörling]

On 19 Apr 2016 22:20 +0200, from ralf+dm@ramses-pyramidenbau.de (Ralf Ramsauer):
> On 04/19/2016 10:06 PM, Arno Wagner wrote:
>> Now, if you want to lose all data, here is what you can try:
>> 1. Resize filesystem in LUKS container to half device size.
> 
> Joe has 2.8/4 TiB in use. I think it only works in-situ which is at
> least as double as dangerous as your approach :-)

Joe also has 12 TB of storage space available, and has already shrunk
the btrfs file system to 4 TiB. I think a plausible argument can be
made that there is room for two copies of the data.

-- 
Michael Kjörling • https://michael.kjorling.se • michael@kjorling.se
                 “People who think they know everything really annoy
                 those of us who know we don’t.” (Bjarne Stroustrup)

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Ralf Ramsauer]

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Hi,

Hmm, you would have to 'move' your header together with btrfs to some
higher address to get free space at the beginning of the disk for the
partition table and the new header. I would _not_ even think about
trying it if data loss is a threat to you...

In a very informal way: you can shrink your btrfs to minimum and use dd
to move it to move 'in-situ' it to some higher offset inside the luks
block device (this is really dangerous, erroneous dd arguments lead to
data loss, a power failure is probably not recoverable). Now that you
have enough space at the beginning of your underlying block device, you
can create a partition table and restore the header back to the first
partition. Then you have to adjust the sector offsets by using luksOpen
twice: for the new luks block device and for the old one, passing the
right offset to luksOpen. Then dump your btrfs back from the old luks
device to the new one.

*Any* step might fail and cause unrecoverable data loss and this
approach is really dangerous.
Anyone better suggestions?

  Ralf

PS: I had a similar issue some years ago: I wanted to change my Raid
(luks inside) from Raid6 (4x3TiB) to Raid10. I degraded  the Raid6 by
two disks and created a new degraded Raid10 and dumped data from A to B.
Afterwards I added the two remaining Raid6 disks to the new Raid10.
Luckily, everything worked out, but I would not try it again.

On 04/19/2016 09:08 PM, Joe Hillenbrand wrote:
> I posted this to https://gitlab.com/cryptsetup/cryptsetup/issues/292
> but now I'm worried that might not be the appropriate place to ask
> questions.
>
> I have a 12TB hardware RAID5 external hard drive array.
>
> I had initially planned to only ever encrypt data to the device, but
> now I need about half encrypted and half not.
>
> The device is `/dev/sdd`. It mounts as `fatty`.
>
> There is no partition table.
>
>     # dd if=/dev/sdd | hexdump -C | head -1
>     00000000  4c 55 4b 53 ba be 00 01  61 65 73 00 00 00 00 00 
> |LUKS....aes.....|
>
>     # parted /dev/sdd
>     GNU Parted 3.2
>     Using /dev/sdd
>     Welcome to GNU Parted! Type 'help' to view a list of commands.
>     (parted)
> print                                                           
>     Error: /dev/sdd: unrecognised disk label
>     Model: ORICO H/ W RAID5
> (scsi)                                           
>     Disk /dev/sdd: 12.0TB
>     Sector size (logical/physical): 512B/4096B
>     Partition Table: unknown
>     Disk Flags:
>
> 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.
>
>     # cryptsetup status fatty
>     /dev/mapper/fatty is active.
>       type:    LUKS1
>       cipher:  aes-xts-plain64
>       keysize: 256 bits
>       device:  /dev/sdd
>       offset:  4096 sectors
>       size:    23441764352 sectors
>       mode:    read/write
>
>     # btrfs filesystem show /dev/mapper/fatty
>     Label: 'fatty'  uuid: XXX-XX-XX-XX-XXXXXXXXX
>         Total devices 1 FS bytes used 2.75TiB
>         devid    1 size 4.00TiB used 2.80TiB path /dev/mapper/fatty
>
> 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?
>
>
>
> _______________________________________________
> dm-crypt mailing list
> dm-crypt@saout.de
> http://www.saout.de/mailman/listinfo/dm-crypt


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Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Joe Hillenbrand]

Based on Milan's suggestion in the gitlab issue
(which was to dd 4TiB to another part of the device).
It looks like the first step is to figure out the exact number of blocks that
the btrfs filesystem lives on and where they are.

It turns out that 'cryptsetup resize' doesn't do what I though it did.

# blockdev --getsize /dev/sdd
23441768448
# blockdev --getsize /dev/mapper/fatty
23441764352

Is it safe to assume that the filesystem lives from blocks 4096 to
8589934592 (4TiB / 512 Bytes) + 4096?

8589934592 + 4096 = 8589938688

I'll add an extra 1GiB between the existing filesystem to the new filesystem.

(((4 TiB) + (1 GiB)) / (512 bytes)) + 4096 = 8592035840

Thus, this is what I think the dd command should be:

dd if=/dev/sdd of=/dev/sdd count=8589938688 seek=8592035840 bs=512

I will then be able to add a GPT and create an entry pointing to 8592035840.
Then if something goes wrong, I should be able to recover using:

dd if=/dev/sdd of=/dev/sdd count=8589938688 skip=8592035840 bs=512

Does this seem correct?

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[f-dm-c]

I know you don't want to throw hardware at the problem, but if your
data now fits in 4TB, I'd recommend that you buy a 4TB drive, put
LUKS on it, copy the data to it, reconfigure your 12TB RAID5, move
the data back to the RAID, and then return the drive, paying the
restocking fee.  Or sell it privately.  Unless your time is free
and your data is valueless, this seems the most straightforward
way to solve the problem.  Note that you need not wipe the returned
drive, since you put LUKS on it first, though if you want to be
super-paranoid, wipe the first few megabytes of it before return.

If you don't trust having your data on a single drive during the
process, buy two 4TB drives and copy twice.  Don't make them a RAID;
that just makes everything more complicated and more prone to failure
or mistakes.  Just make two copies and leave one copy on the shelf
while you copy back over your 12TB RAID.  Or, if you have backups of
your RAID already (you -do- have backups, right?  else you shouldn't
be considering your data safe even when you're -not- monkeying with
the RAID), then maybe a single 4TB copy is enough, assuming that you
have checked that your backups are actually backups and not something
you can't read or perhaps something that was never written.

And if you didn't have backups, then keep the drive(s), and now you do.

Since it's a RAID5, you -could- live more dangerously and fail enough
drive(s) to get 4TB of free drives out of it instead of buying new
drive(s), and then re-add the drive(s) when everything's done.  But
this raises the chances that something will go wrong and leave you
with a smoking crater instead of your data.

P.S.  And next time, don't scrimp on "wasting" a disk sector to avoid
having a partition table.  Don't even worry about "wasting" a possible
megabyte (default alignment) at the start of each partition.  Your
12TB RAID will never notice.  And this way, certain other software
(like installers) are less likely to believe that the disk is blank
and write something unfortunate to it, like a partition table in the
middle of your RAID or LUKS headers.

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Joe Hillenbrand]

I was worried about this. Turns out since there is no partition table,
I don't think I can be sure that btrfs only lives on the first 4TiB.

    # parted /dev/mapper/fatty
    GNU Parted 3.2
    Using /dev/mapper/fatty
    Welcome to GNU Parted! Type 'help' to view a list of commands.
    (parted) print
    Model: Linux device-mapper (crypt) (dm)
    Disk /dev/mapper/fatty: 12.0TB
    Sector size (logical/physical): 512B/4096B
    Partition Table: loop
    Disk Flags:

    Number  Start  End     Size    File system  Flags
    1      0.00B  12.0TB  12.0TB  btrfs

    (parted) unit s
    (parted) print
    Model: Linux device-mapper (crypt) (dm)
    Disk /dev/mapper/fatty: 23441764352s
    Sector size (logical/physical): 512B/4096B
    Partition Table: loop
    Disk Flags:

    Number  Start  End           Size          File system  Flags
    1      0s     23441764351s  23441764352s  btrfs


I'm having a terrible time trying to figure out a way to confirm on
which blocks the filesystem lives.

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Joe Hillenbrand]

Oh, I'm so sorry! I thought nobody was responding to my emails. I
didn't realize I to be subscribed to the list to get responses.
Looking at the archive I'm seeing some very good advice. I'll respond
as best I can.

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Joe Hillenbrand]

As many of you suggested, since I only have 2.8TiB of actual data, It
wouldn't hurt to just buy a 3TB drive for this process. It's better to
just spend the money rather than risk losing my data.

It's not like I won't have a use for it in the future. I even have an
extra slot in my RAID array, so I can just stick it there.

Turns out this problem just needed counseling rather than technical advice. ;)

Thank you!

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[David Christensen]

On 04/20/2016 12:54 PM, Joe Hillenbrand wrote:
> As many of you suggested, since I only have 2.8TiB of actual data, It
> wouldn't hurt to just buy a 3TB drive for this process. It's better to
> just spend the money rather than risk losing my data.
>
> It's not like I won't have a use for it in the future. I even have an
> extra slot in my RAID array, so I can just stick it there.
>
> Turns out this problem just needed counseling rather than technical advice. ;)

If you're going to buy one disk just for 2.8 TiB of data and plan to put 
it into your RAID array later, get a drive that matches the drives that 
are already in your RAID array (4 TB NAS HDD?).


Checking prices on Amazon for my 8 TB desktop HDD and mobile rack as a 
backup device suggestion:

- Seagate desktop HDD 8 TB $320

	http://www.amazon.com/dp/B019OSCLH8

- StarTech mobile rack $65

	http://www.amazon.com/dp/B0000E2Y8P

So, $385+ USD for a 8 TB desktop HDD with mobile rack.


Then I discovered that Seagate makes an "Archive" HDD. This may or may 
not be the right drive for your application, depending upon your process 
and tools:

- Seagate archive HDD 8 TB $215

	http://www.amazon.com/dp/B00XS423SC

So, $280+ USD for 8 TB archive HDD with mobile rack.


David

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[Arno Wagner]

Excellent, that is the smart move. You are welcome.

Regards,
Arno

On Wed, Apr 20, 2016 at 21:54:48 CEST, Joe Hillenbrand wrote:
> As many of you suggested, since I only have 2.8TiB of actual data, It
> wouldn't hurt to just buy a 3TB drive for this process. It's better to
> just spend the money rather than risk losing my data.
> 
> It's not like I won't have a use for it in the future. I even have an
> extra slot in my RAID array, so I can just stick it there.
> 
> Turns out this problem just needed counseling rather than technical advice. ;)
> 
> Thank you!
> _______________________________________________
> dm-crypt mailing list
> dm-crypt@saout.de
> http://www.saout.de/mailman/listinfo/dm-crypt

-- 
Arno Wagner,     Dr. sc. techn., Dipl. Inform.,    Email: arno@wagner.name
GnuPG: ID: CB5D9718  FP: 12D6 C03B 1B30 33BB 13CF  B774 E35C 5FA1 CB5D 9718
----
A good decision is based on knowledge and not on numbers. -- Plato

If it's in the news, don't worry about it.  The very definition of 
"news" is "something that hardly ever happens." -- Bruce Schneier

Re: [dm-crypt] LUKS is written to a device with no partition table. Is it possible to add a partition table?

[David Christensen]

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 
your computer?


> 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):

	https://www.startech.com/HDD/Mobile-Racks/Black-Serial-ATA-Drive-Drawer-with-Shock-Absorbers-Professional-Series~DRW115SATBK


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.


David