Way back in the day — back in March of two thousand-naught-eleven, I added a blog post on how to encrypt a partion using crypsetup and luks on RHEL. Its title, ironically enought was, RHEL, How to Encrypt a Partition Using Cryptsetup and Luks.
Today we are going to talk about how to revert an encyrpted partion back to its unencrypted state so that i can use my usb drive normally again.
# cryptsetup status freeagent
/dev/mapper/freeagent is active.
type: LUKS1
cipher: aes-cbc-essiv:sha256
keysize: 256 bits
device: /dev/sdd1
offset: 4096 sectors
size: 2930267906 sectors
mode: read/write
First take note of the device name and the name the dev mapper has given the device. The former is /dev/sdd1 and the latter is /dev/mapper/freeagent.
So first lets remove the key file mapping. You will be prompted for your LUKS passphrase
#cryptsetup luksRemoveKey /dev/sdd1
Enter LUKS passphrase to be deleted:
Then lets remove the dev/mapper mapping for /dev/sdd1. Once complete we are free to create a new filesystem on the disk as needed.
#cryptsetup remove /dev/mapper/freeagent /dev/sdd1