Mount a LUKS Encrypted partition on Linux boot

1. get THE UUID from blkid

Ex    /dev/mapper/encrypted-partition: UUID="d62cb037-e5ba-4f49-a92a-69705e4bae2b" TYPE="crypto_LUKS"

not    /dev/mapper/luks-d62cb037-e5ba-4f49-a92a-69705e4bae2b: UUID="f6d930b6-b75b-440c-9b41-67ed538bdd75" TYPE="ext4"

2. qdd napper name to /etc/crypttab

The partition will appear as a device in /dev/mapper/<mapper name>.

Entries in /etc/crypttab are of the form

<mapper name> UUID=<UUID>

Example 1:

decrypted-partition UUID=d62cb037-e5ba-4f49-a92a-69705e4bae2b

Example 2:

decrypted-partition UUID=d62cb037-e5ba-4f49-a92a-69705e4bae2b none luks

For more information on /etc/crypttab, see $ man crypttab.

3.Edit /etc/fstab and add

Example 1.

/dev/mapper/decrypted-partition /media/ext-hdd ext4 defaults 1 2

Example 2.

/dev/mapper/decrypted-partition /media/ext-hdd ext4 defaults,x-gvfs-name=ENC 1 2

Example 3

decrypted-partition UUID=d62cb037-e5ba-4f49-a92a-69705e4bae2b none luks

4. Reboot

Note

The next time you boot your system you will be prompted for the passphrase and the partition will be mounted to the given mount point. The output of $ blkid should now contain

/dev/mapper/encrypted-partition: UUID="d62cb037-e5ba-4f49-a92a-69705e4bae2b" TYPE="crypto_LUKS"

/dev/mapper/decrypted-partition: UUID="93f9bbf4-4e4f-4647-85f3-4fbba7d7a21f" TYPE="ext4"

Tips

Change UUID of LUKS encrypted partition.

1. Generate new uuid using uuidgen

2. cryptsetup luksUUID /dev/sda1 --uuid "THE-NEW-UUID"

Set / Change UUID of a partition

sudo tune2fs /dev/sde5 -U 507fe741-bf59-40f4-8cef-6b0803f11f30