Can I Disable Full-Disk Encryption?
I Recently Installed Ubuntu 12.10 and It Requires a Passphrase to Boot up (I Installed It with an Encrypted File System). Do I Have to Reinstall to Change to a...
I recently installed Ubuntu 12.10 and it requires a passphrase to boot up (I installed it with an encrypted file system).
Do I have to reinstall to change to a standard unencrypted file system?
6 Answers
If Ubuntu asks for an encryption passphrase during boot (i.e. on the text console before the login screen is displayed), this indicates that a full disk encryption method was used. (There's more than one way to do this, but I'll keep the answer general.) The encryption is handled by an extra software layer between the file system and the physical hard drive, not the file system itself.
There is no simple method or tool to undo this. With some knowledge about how Linux systems work, it can be done. You'd have to move the whole file system (or all files) to another partition (with enough free space) or external HDD. Then, remove the encrypted container, and recreate the file system without encryption. Finally, make sure that the new file system is properly recognized by the boot loader and mount -a before rebooting.
If possible, it's best to avoid this time consuming and error-prone procedure. Just do a fresh install. For a new users, this is the quickest and safest option.
PS: Chances are that you can change the encryption passphrase, possibly to an empty string. Then decrypting only requires to press Enter. Maybe you can go further and supress to (now useless) passphrase prompt. However, this does not disable the encryption. The data would still be encrypted although the encryption would be useless since the key can be trivially guessed.
Below it's my solution that worked. Bear in mind that I am not Linux specialist, so it may be not the best solution. Could not find better one anyway.
Migrating FDE installation to unencrypted partition
NOTE: Whenever I say, I mean
/dev/sda1 - boot partition
/dev/sda5 - encrypted partition
/dev/sda3 - clean non-encrypted EXT4 partition
/dev/sda2 - my newly created swap partition
Must Read
Copying data from encrypted root filesystem
Boot from a live CD. I've used Ubuntu 13.10 32bit desktop ISO.
Mount your partition:
sudo cryptsetup luksOpen /dev/sda5 crypt1
Copy your source data to destination partition and save dd PID to pid variable:
sudo dd if=/dev/ubuntu-vg/root of=/dev/sda3 bs=1M & pid=$!
This will ping each second dd process with USR1 signal and dd results status:
while sudo kill -USR $pid; do sleep 1; done
Alternative to monitoring DD
If you don't like above 'while method', you can use watch. Open different terminal window and get the PID:
pgrep -l '^dd$' | awk '{ print $1 }'
Replace with your process ID:
watch kill -USR1 <pid>
You should see output in your dd terminal each 2s.
Maya is a hardware enthusiast who tests and reviews smart home devices, smartphones, wearables, and audio gear. She focuses on practical consumer value and build quality.
