3

Is it possible to encrypt an existing dataset (including snapshots) in ZFS on Linux >= 0.8, e.g. by using send | recv and destruction of the original dataset?

1

Yes, it is. See this simple example (tested on ZoL 0.8.3).

If you would like to use a raw keyfile (rather than a passphrase):

dd if=/dev/urandom of=/path/to/keyfile bs=32 count=1
chmod 000 /path/to/keyfile

Create a snapshot first:

zfs snapshot -r tank/home@transfer

Then, as proposed, send | recv (with replication option -R), but provide your encryption options on the receive side:

zfs send -R tank/home@transfer |
    zfs receive \
        -o encryption=aes-256-gcm \
        -o keyformat=raw \
        -o keylocation=file:///path/to/keyfile \
        tank/newhome

If the original dataset is mounted, the new one will not be mounted straightaway:

cannot mount '/tank/home': directory is not empty

Destroy the unencrypted dataset and replace it with your new one:

zfs destroy -r tank/home
zfs rename tank/newhome tank/home

If your dataset does not have any children, mounting is easy:

zfs mount tank/home

else

zfs list -rH -o name tank/home | xargs -L 1 zfs mount

(or simply zfs mount -a if you don’t have other datasets which should not be mounted).

And that was about it!

Finally, destroy the snapshot, if you like:

zfs destroy -r tank/home@transfer
|improve this answer|||||

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.