I'm aware of encrypting home folders, but I want to use LUKS encryption to encrypt my root partition, but LEAVE room for a /backup partition that is not encrypted. The alternate cd requires encrypting the whole disk.

How do I do this?


A way around missing functionality in the installer is to prepare the disk before.

You can use a live or rescue CD to prepare the disk as you want. I would suggest to create 2 volume-groups, one encrypted and the other unencrypted.

Afterwards you should be able in the installer to pick up this volume-groups.

  • Thank you very much. Can you walk me through how to use a livecd to build a small encrypted volume? Is it system-config-lvm? My goal is to have a small / root volume that is encrypted and i can backup and restore anytime – Alexander Tritan Sep 22 '12 at 23:51
  • @AlexanderTritan You don't have to use LVM to encrypt a partition. If you haven't looked at ecryptfs, take a look at my reply, it may of help, I've done the same to backup my /home. – Terry Wang Nov 5 '12 at 23:09
  • @AlexanderTritan If your problem is resolved, don't forget to close this question. – H.-Dirk Schmitt Mar 13 '13 at 12:16

Using a separate encrypted volume for backups would be better. Having a perfect plain text copy of your encrypted data sitting right next to it completely defeats the purpose of having the encrypted drive. If anything, one could just use your plain text to figure out the encryption. That may seem far fetched but, I have no need of getting into your encrypted volume if I can just access the backup.


In fact Ubuntu's encrypted home directory is based on eCryptfs;-)

If you want to have a small encrypted partition for backup/restore, an easy workaround would be using ecryptfs.

ecryptfs is flexible and easy to use, layering on top of the current filesystem for example: ext4 or btrfs.

Basically you have a partition/block device, create file system and mount it, then use ecryptfs to encrypt it. For example, suppose you have /dev/sda5, you create ext4 on top of it and mount it as /topsecret, to encrypt it


  1. install ecryptfs-utils package 1st

    sudo apt-get install ecryptfs-utils
  2. mount the destination directory as ecryptfs

    mount -t ecryptfs /topsecret /topsecret

NOTE: You will then be prompted for some details on how ecryptfs should encrypt the data.

Now, you can copy data on your / partition to the encrypted file system (more like a container), for example using rsync (better to do it offline - I mean boot the system from a live CD and do it)

Suppose you boot from a live CD and mount your / as /mnt/root and the ecryptfs as /mnt/topsecret

rsync -axHAX /mnt/root /mnt/topsecret

For more info, e.g automatically mount etc. https://help.ubuntu.com/12.04/serverguide/ecryptfs.html

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.