How to encrypt partition in Linux - undo encryption

I used this to encrypt a disk and all is well. But now I would like to undo it as I will be using a different method with Ubuntu 24.04. How do I reverse this so that LUKS, cryptsetup and /dev/mapper will no longer interfere with normal linux operations?

Hello,

Not sure what you mean exactly by “undo”. Please tell us what exactly you wish to do? Are you currently using Ubuntu 24.04 or some other system?

Perhaps the best solution is to backup your data to external drive and after that simply make fresh Ubuntu system install.

Lubos

What I am trying to do, is to reformat the drive to an ext4 file system without encryption. But I am not sure if after booting, the LUKS-cryptsetup-/dev/mapper will interfer with mounting the newly reformated partition. Will the newly formatted partition ask for the passphrase on bootup? Do I need to delete the /dev/mapper line in /etc/fstab (currently just commented out)? Will any of the LUKS-cryptsetup-dev/mapper software still think there is an encrypted partition to mount and thus stop or interfere with the bootup?

Sure! Just use the “Erase disk and install Ubuntu” option during setup. It’ll wipe everything, including the LUKS encryption, and set up fresh partitions automatically. Just make sure to back up your data first! I’m still not sure what your intentions are, if you want to just reformat a partition and keep the existing system or if you plan to install a new system. Based on your last reply, you mentioned reformatting the drive, so I assume you’re going for a fresh Ubuntu installation.

Thank you for the information. Yes, I am upgrading 22.04 to 24.04 and just want to make sure the LUKS/cryptsetup won’t interfere with the boot process even though the disk has been reformatted.
I have backed up the data to my NAS, so Thanks Again for the help!!